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c65manualupdated.txt
***NOTE***
This document was updated by Ken Sumrall on 3/26/06. I've noted my
updates with the notation ***KEN***. They are all in the CPU section.
***NOTE***
(*TODO*: remove above note, once all ***KEN*** remarks are integrated)
C64DX SYSTEM SPECIFICATION
o Design Concepts
o Hardware Specifications
o Software Specifications
Requires ROM Version 0.9A.910228 or later.
COPYRIGHT 1991 COMMODORE BUSINESS MACNINES, INC.
ALL RIGHTS RESERVED.
INFORMATION CONTAINED HEREIN IS THE UNPUBLISHED AND CONFIDENTIAL
PROPERTY OF COMMODORE BUSINESS MACHINES, INC. USE, REPRODUCTION, OR
DISCLOSURE OF THIS INFORMATION WITHOUT THE PRIOR WRITTEN PERMISSION OF
COMMODORE IS PROHIBITED.
CCCC 666 555555
C C 6 5
C 6 5
C 6 55555
C 66666 5 5
C 6 6 5
C 6 6 5
C C 6 6 5 5
CCCC 6666 5555
Copyright 1991 Commodore Business Machines, Inc.
All Rights Reserved.
This documentation contains confidential, proprietary, and unpublished
information of Commodore Business Machines, Inc. The reproduction,
dissemination, disclosure or translation of this information to others
without the prior written consent of Commodore Business Machines, Inc.
is strictly prohibited.
Notice is hereby given that the works of authorship contained herein
are owned by Commodore Business Machines, Inc. pursuant to U.S.
Copyright Law, Title 17 U.S.C. 3101 et. seq.
This system specification reflects the latest information available at
this time. Updates will occur as the system evolves. Commodore
Business Machines, Inc. makes no warranties, expressed or implied with
regard to the information contained herein including the quality,
performance, merchantability, or fitness of this information or the
system as described.
This system specification contains the contributions of several people
including: Fred Bowen, Paul Lassa, Bill Gardei, and Victor Andrade.
Portions of the BASIC ROM code are Copyright 1977 Microsoft.
PPPP RRRR EEEE L I M M I N N A RRRR Y Y
P P R R E L I MM MM I NN N A A R R Y Y
PPPP RRRR EEE L I M M M I N N N AAAAA RRRR Y
P R R E L I M M I N NN A A R R Y
P R R EEEE LLLL I M M I N N A A R R Y
Revision 0.2 (pilot release) January 31, 1991
At this time, Pilot Production, the C65 system consists of either
revision 2A or 2B PCB, 4510R3, 4567R5 (PAL only), F011B/C FDC, and 018
DMAgic chips. There will be changes to all these chips before
Production Release.
This work is by:
Fred Bowen System Software - C65
Paul Lassa Hardware engineer - C65, DMagic
Bill Gardei LSI engineer - 4567, FDC
Victor Andrade LSI engineer - 4510
Included are contributions by contractors hired by Commodore for the
C65 project. These contributions include the DOS, Graphics, Audio, and
Memory management areas.
Several 4502 assembler systems are available:
VAX, Amiga, and PC based BSO-compatible cross assemblers.
PC based custom cross assembler by Memocom, compatible
with Memocom 4502 emulator and Mem-ulator systems.
C128-based BSO compatible cross assembler by Commodore.
Custom software support is available for the following logic
analyzers:
Hewlett Packard HP655x A and B logic analyzers.
Table of Contents
-----------------
1.0. Introduction
1.1. System Concept
1.2. System Overview
1.3. System Components
1.4. System Concerns
1.4.1. C64 Compatibility
1.4.1.1. Software
1.4.1.2. Hardware
1.4.2. 1581 DOS Compatibility
1.4.3. Modes of Operation
1.5. System Maps
1.5.1. Composite System Memory Map
1.5.2. C65 System Memory Map
1.5.3. C65 System Memory Layout
1.5.4. C65 I/O Memory Map
2.0. System Hardware
2.1. Keyboard
2.1.1. Keyboard Layout
2.1.2. Keyboard Matrix
2.2. External Ports & Form-Factor
2.3. Microcontroller
2.3.1. Description
2.3.2. Configuration
2.3.3. Functional Description
2.3.3.1. Pin Description
2.3.3.2. Timing Description
2.3.3.3. Register Description
2.3.4. Mapper
2.3.5. Peripheral Control
2.3.5.1. I/O Ports
2.3.5.2. Handshaking
2.3.5.3. Timers
2.3.5.4. TOD Clocks
2.3.5.5. Serial Ports
2.3.5.6. Fast Serial Ports
2.3.5.7. Interrupt Control
2.3.5.8. Control Registers
2.3.6. UART
2.3.6.1. Control Registers
2.3.6.2. Status Register
2.3.6.3. Character Configuration
2.3.6.4. Register Map
2.3.7. CPU
2.3.7.1. Introduction
2.3.7.2. CPU Operation
2.3.7.3. Interrupt Handling
2.3.7.4. Addressing Modes
2.3.7.5. Instruction Set
2.3.7.6. Opcode Table
2.4. Video Controller
2.4.1. Description
2.4.2. Configuration
2.4.3. Functional Description
2.4.4. Programming
2.4.5. Registers
2.4.6. Limitations and Avoiding Them
2.5. Disk Controller
2.5.1. Description
2.5.2. Configuration
2.5.3. Registers
2.5.4. Functional Description
2.5.5. Expansion port protocol
2.5.6. Timing diagrams
2.6. Expansion Disk Controller (option)
2.6.1. Description
2.6.2. Expansion port protocol
2.7. DMAgic Controller
2.7.1. Description
2.7.2. Registers
2.8. RAM Expansion Controller (option)
2.8.1. Description
2.9. Audio Controller
3.0. System Software
3.1. BASIC 10.0
3.1.1. Introduction
3.1.2. List of Commands
3.1.3. Command Descriptions
3.1.4. Variables
3.1.5. Operators
3.1.6. Error Messages
3.1.6.1. BASIC Error Messages
3.1.6.2. DOS Error Messages
3.2. Monitor
3.2.1. Introduction
3.2.2. Commands and Conventions
3.2.3. Command Descriptions
3.3. Editor
3.3.1. Escape Sequences
3.3.2. Control Characters
3.4. Kernel
3.4.1. Kernel Jump Table
3.4.2. BASIC Jump Table
3.4.3. Editor Jump Table
3.4.4. Indirect Vectors
3.4.5. Kernel Documentation
3.4.6. BASIC Math Package Documentation
3.4.7. I/O Devices
3.5. DOS
3.6. RS-232
4.0. C65 DMAgic (F018B) DMA Coprocessor
4.1. Introduction
4.2. DMAT External Registers
4.3. DMAT Internal Registers
4.4. Memory Layout
4.5. Using DMAgic from BASIC
4.5.1. Linear Examples
4.5.2. Modulo Example
4.5.3. XY_Mod Example
4.5.4. Barrel Shifter Example
A. Development Support
B. C64DX System Specification UPDATE
1.0. Introduction
This specification describes the requirements for a low-cost 8-bit
microcomputer system with excellent graphic capabilities.
1.1. System Concept
The C65 microcomputer is a low-cost, versatile, competitive product
designed for the international home computer and game market.
The C65 is well suited for first time computer buyers, and provides an
excellent upgrade path for owners of the commercially successful
C64. The C65 is composed of concepts inherent in the C64 and C128.
The purpose of the C65 is to modernize and revitalize the 10 year old
C64 market while still taking advantage of the developed base of C64
software. To accomplish this, the C65 will provide a C64 mode of
operation, offering a reasonable degree of C64 software compatibility
and a moderate degree of add-on hardware and peripheral compatibility.
Compatibility can be sacrificed when it impedes enhanced functionality
and expandability, much as the C64 sacrificed VIC-20 compatibility.
It is anticipated that the many features and capabilities of the new
C65 mode will quickly attract the attention of developers and
consumers alike, thereby revitalizing the low-end home computer
market. The C65 incorporates features that are normally found on
today's more expensive machines, continuing the Commodore tradition of
maximizing performance for the price. The C65 will provide many new
opportunities for third party software and hardware developers,
including telecommunications, video, instrument control (including
MIDI), and productivity as well as entertainment software.
1.2. System Overview
o CPU -- Commodore CSG4510 running at 1.02 or 3.5 Mhz
o New instructions, including Rockwell and GTE extensions,
see section 2.3.7.1 for details on the extensions.
o Memory Mapper supporting up to 1 Megabyte address space
o R6511-type UART (3-wire RS-232) device, programmable baud
rate (50-56K baud, MIDI-capable), parity, word size, sync
and async. modes. XD/RD wire ORed/ANDed with user port.
o Two CSG6526-type CIA devices, each with 2 I/O ports
programmable TOD clocks, interval timers, interrupt control
o Memory
o RAM -- 128K bytes (DRAM)
Externally expandable from additional 512K bytes to 4MB
using dedicated RAM expansion port.
o ROM -- 128K bytes
C64 Kernel and BASIC 2.2
C65 Kernel, Editor, BASIC 10.0, ML Monitor (like C128)
DOS v10 (1581 subset)
Multiple character sets: 40 and 80 column versions
National keyboards/charsets for foreign language systems
Externally expandable by conventional C64 ROM cartridges
via cartridge/expansion port using C64 decodes.
Externally expandable by additional 128K bytes or more
via cartridge/expansion port using new system decodes.
o DMA -- Custom DMAgic controller chip built-in
Absolute address access to entire 1MB system map
including I/O devices, both ROM & RAM expansion ports.
List-based DMA structures can be chained together
Copy (up,down,invert), Fill, Swap, Mix (boolean Minterms)
Hold, Modulus (window), Interrupt, and Resume modes,
Block operations from 1 byte to 64K bytes
DRQ handshaking for I/O devices
Built-in support for (optional) expansion RAM controller
o Video -- Commodore CSG 4567 enhanced VIC chip
o RGBA with sync on all colors or digital sync
o Composite NTSC or PAL video, separate chroma/luma
o Composite NTSC or PAL digital monochrome
o RF TV output via NTSC or PAL modulator
o Digital foreground/background control (genlock)
o All original C64 video modes:
40x25 standard character mode
Extended background color mode
320x200 bitmap mode
Multi-color mode
16 colors
8 sprites, 24x21
o 40 and 80 character columns by 25 rows:
Color, blink, bold, inverse video, underline attributes
o True bitplane graphics:
320 x 200 x 256 (8-bitplane) non-interlaced
640 x 200 x 16* (4-bitplane) non-interlaced
1280 x 200 x 4* (2-bitplane) non-interlaced
320 x 400 x 256 (8-bitplane) interlaced
640 x 400 x 16* (4-bitplane) interlaced
1280 x 400 x 4* (2-bitplane) interlaced
*plus sprite and border colors
o Color palettes:
Standard 16-color C64 ROM palette
Programmable 256-color RAM palette, with 16 intensity
levels per primary color (yielding 4096 colors)
o Horizontal and vertical screen positioning verniers
o Display Address Translator (DAT) allows programmer to
access bitplanes easily and directly.
o Access to optional expansion RAM
o Operates at either clock speed without blanking
o Audio -- Commodore CSG8580 SID chips
o Stereo SID chips:
Total of 6 voices, 3 per channel
Programmable ADSR envelope for each voice
Filter, modulation, audio inputs, potentiometer
Separate left/right volume, filter, modulation control
o Disk, Printer support --
o FDC custom MFM controller chip built in, with 512-byte
buffer, sector or full track read/write/format, LED and
motor control, copy protection.
o Built-in 3.5" double sided, 1MB MFM capacity drive
o Media & file system compatible with 1581 disk drive
o Supports one additional "dumb" drive externally.
o Standard CBM bus serial (all modes, about 4800 baud)
o Fast serial bus (C65 mode only, about 20K baud)
o Burst serial (C65 mode only, about 50K baud)
o External ports --
o 50-pin Cartridge/expansion port (ROM cartridges, etc.)
o 24-pin User/parallel port (modem (1670), RS-232 serial)
o Composite video/audio port (8-pin DIN)
o Analog RGB video port (DB-9)
o RF video output jack
o Serial bus port (disks (1541/1571/1581), printers, etc.)
o External floppy drive port (mini DIN8)
o 2 DB9 control ports (joystick, mouse, tablets, lightpen)
o Left and right stereo audio output jacks
o RAM expansion port, built-in support for RAM controller
o Keyboard -- 77 keys, including standard C64 keyboard plus:
o Total of 8 function keys, F1-F16, shifted and nonshifted
o TAB, escape, ALT, CAPS lock, no scroll, help (F15/16)
o Power, disk activity LEDs
o Power supply -- external, brick type
o +5VDC at 2.2A and +12VDC at .85A
1.3. System Components
Microcontroller: 4510 (65CE02, 2x6526, 6511 UART, Mapper,
Fast serial)
Memory: 4464 DRAM (128K bytes)
271001 ROM (128K bytes)
Video controller: 4567 (extended VIC, DAT, PLA)
Audio controllers: 6581 (SID)
Memory control: 41xx-F018 (DMA)
Disk controller: 41xx-F011 (FDC, supports 2 DSDD drives, MFM,
RAM buffer)
KEYS
+ USER PORT
| + CONTROL PORTS EXPANSION PORT
| | + + + + +---+
| | | | | | | | +MOD-> RFOUT
++-+-++ | | | | +-+----> COMP,CHROMA/LUMA
| | | | | | +------> RGBA
| +-------------------------------------+------+ | +---+
| +--------------------------------------------+ +--...-+ R +--+
| | | | | | E | EXPANSION
| | +---+ +---+ +---+ +---+ +---+ | | | +--...-+ C +--+ MEMORY
| 4 | | | | | | | | | | | | | | 4 | +---+
| 5 +-----+ D +--+ F +--+ S +--+ S +--+ R +-+----+ 5 | +--+ +--+ +--+ +--+
| 1 +-----+ M +--+ D +--+ I +--+ I +--+ O +------+ 6 | | | | | | | | |
| 0 | ADR | A | | C | | D | | D | | M | | | 7 +--+ +--+ +--+ +--+ |
| | | G | | | | | | | | | | | +--+ +--+ +--+ +--+ |
| +-----+ I +--+ +--+ +--+ +--+ +---+--+ +--+ +--+ +--+ +--+ |
| +-----+ C +--+ +--+ +--+ +--+ +------+ +--+ +--+ +--+ +--+ |
| | DAT | | | | | | | | | | | | | | | | | | | |
+--+--+ +---+ +++-+ +-+-+ +-+-+ +---+ +---+ +--+ +--+ +--+ +--+
| || | | 128K
+ || R L RAM INTERNAL
SERIAL BUS || SPEAKERS
++
FLOPPY PORT
1.4. System Concerns
1.4.1. C64 Compatibility Issues
1.4.1.1. Software
C64 software compatibility is an important goal. To this end, when the
system is in "C64 mode" the processor will operate at average 1.02MHz
speed and dummy "dead" cycles are emulated by the processor. The C64
ROM is the same except for patches to serial bus routines in the
kernel (to interface built-in drive), the removal of cassette code
(there is no cassette port), and patches to the C64 initialization
routines to boot C65 mode if there is no reason (eg., cartridges) to
stay in C64 mode.
Compatibility with C64 software that uses previously unimplemented
6502 opcodes (often associated with many copy-protection schemes) or
that implements extremely timing dependent "fast loaders" is iherently
impossible. Because the VIC-III timing is slightly different, programs
that are extremely timing dependant may not work properly. Also
because the VIC-III does not change display modes until the end of a
character line, programs that change displays based strictly upon the
raster position may not display things properly. The aspect ratio of
the VIC-III display is slightly different than the VIC-II. The use of
a 1541-II disk drive (optional) will improve compatibility. C64 BASIC
2.2 compatibility will be 100% (within hardware constraints). C128
BASIC 10 compatibility will be moderate (graphic commands are
different, some command parameters different, and there are many new
commands).
1.4.1.2. Hardware
C64 hardware compatibility is limited. Serial bus and control port
devices (mouse, joysticks, etc.) are fully supported. Some user port
devices are supported such as the newer (4-DIP switch) 1670 modems,
but there's no 9VAC so devices which require 9VAC won't function
correctly. The expansion port has additional pins (50 total), and the
pin spacing is closer than the C64 (it's like the PLUS/4). An adaptor
("WIDGET") will be necessary to utilize C64 cartridges and expansion
port devices. Furthermore, timing differences between some C64 and C65
expansion port signals will affect many C64 expansion devices (such as
the 1764).
1.4.2. DOS Compatibility
The built-in C65 DOS is a subset of Commodore 1581 DOS. There is no
track cache, index sensor, etc. To load and run existing 1541-based
applications, the consumer must add a 1541 drive to the system. Many
commercial applications cannot be easily ported from 1541/5.25" media
to 1581/3.5" media, due to copy protection or "fast loaders". Most C64
applications that directly address DOS memory, specific disk tracks
or sectors, or rely on DOS job queues and timing characteristics will
not work with the built-in drive and new DOS.
1.4.3. Operating Modes
The C65 powers up in the C64 mode. If there are no conditions present
which indicate that C64 mode is desired, such as the C= key depressed
or a C64 cartridge signature found, then C65 mode will be
automatically brought into context. Unlike the C128, "C6 4 mode" is
escapable. Like the C128, all of the extended features of the C65
system are accessible from "C64 mode" via custom software. Whenever
the system initiates C64 mode, new VIC mode is always disabled except
when the DOS is required.
1.5. System Maps
1.5.1. Composite System Memory Map
C64 CARTRIDGES C64 C65 RAM-LO RAM-HI
$FFFF+-----------+ +-----------+ +-----------+ +-----------+ +-----------+
| | | | | | | | |COLOR NYBS |
$F800| GAME | | KERNEL | | KERNEL | | | +-----------+
| | | & | | & | | | | |
| CARD | | EDITOR | | EDITOR | | | | |
| | | | | | |.......... | | ......... |
$E000+-----------+ +-----------+ +-----------+ | C65 EVEN | | C65 ODD |
|COLOR NYBS | |COLOR NYBS | | BITPLANES | | BITPLANES |
|I/O & CHARS| |I/O & CHARS| |.......... | | ......... |
$D000 ------------ +-----------+ +-----------+ | | | |
| | | | | |
| KERNEL | | | | |
| | | C65 BASIC | | C65 VARS &|
$C000+-----------+ +-----------+ +-----------+ | TEXT | | STRINGS |
| | | | | | |$2000-$FEFF| |$2000-$F7FF|
|APPLICATION| | | | | | | | |
| | | BASIC | | | | | | |
| CARD _ HI | | | | BASIC | | | | |
| | | | | GRAPHICS | | | | |
$A000+-----------+ +-----------+ | | +-----------+ | |
| | | | | | | |
|APPLICATION| | DOS | | | | |
| | | (MAPPED) | | | | |
| CARD _ LOW| | | | | | |
| | | | | C64 VARS &| | |
$8000+-----------+ ------------- +-----------+ | STRINGS | | |
|COLOR NYBS | | TEXT-$BFFF| | |
|I/O & CHARS| | | | |
$6000 -------------------------- +-----------+ | C64 BASIC | | |
| | | TEXT | | |
| | |$0800-VARS | | |
| | | | | |
| | | | | |
| BASIC | | | | |
| | | | | |
| | | | | |
| | | | | |
$2000 -------------------------- +-----------+ +-----------+ +-----------+
| C65 SYSTEM| | C64 & C65 |
|TEXTSCREENS| | DOS |
$0000 ---------------------------------------- +-----------+ +-----------+
1.5.2. C65 System Memory Map
MAPPER BANK
-----+-----
|
|
1M $F,FFFF +-------------+ ----------
| | 512K BLOCK APPEARING HERE
+- -+ IS DETERMINED BY THE RAM
| RAM | EXPANDER CTLR
768K $C,0000 +- -+ (CURRENTLY 2 BANKS ARE
| EXPANSION | SPECIFIED, MORE MIGHT BE
+- -+ POSSIBILE, BUT ARE NOT
| | DEFINED)
512K $8,0000 +-------------+ ----------
| |
+- RESERVED -+ FUTURE CARTRIDGES
| |
256K $4,0000 +-------------+ ----------
| SYSTEM ROMS |
128K $2,0000 +-------------+ SEE SYSTEM MEMORY
| SYSTEM ROMS | LAYOUT, BELOW
$0,0000 +-------------+ ----------
1.5.3. C65 System Memory Layout
BANK 0 BANK 1 BANK 2 BANK 3
RAM-LO RAM-HI ROM-LO ROM-HI
$FFFF +-------------+ +-------------+ +-------------+ +-------------+
$F800 | | | COLOR NYBS | | C64 | | C65 |
| | +-------------+ | KERNEL | | KERNEL |
$E000 | BITPLANES | | | +-------------+ +-------------+
| (EVEN) | | | | C64 CHRSET | | |
$D000 | | | BITPLANES | +-------------+ | RESERVED |
| | | (ODD) | | INTERFACE | | |
$C000 +.............+ +.............+ +-------------+ +-------------+
| | | | | C64 | | |
| | | | | BASIC | | |
$A000 | STRUCTURES | | STRINGS | +-------------+ | GRAPHICS |
| ??? | | | | C65 | | |
| | | | | CHRSET | | |
$8000 +.............+ +.............+ +-------------+ +-------------+
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| BASIC | | BASIC | | RESERVED | | C65 BASIC |
| TEXT | | VARIABLES | | | | |
| | | | | | | |
| | | | | | | |
$4000 | | | | +-------------+ | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
$2000 +-------------+ +-------------+ | | +-------------+
| TEXT SCREEN | | DOS | | DOS | | MONITOR |
+-------------+ | | | | | |
| | | BUFFERS | | (MAPS TO | | (MAPS TO |
| SYSTEM VARS | | & VARS | | $8000) | | $6000) |
| | | | | | | |
$0000 +-------------+ +-------------+ +-------------+ +-------------+
What does this mean? Here is what the 64K memory map looks like in
various configurations (i.e., as seen by the processor):
C64 mode: $E000-$FFFF Kernel, Editor, Basic overflow area
--------- $D000-$DFFF I/O and Color Nybbles, Character ROM
$C000-$CFFF Application RAM
$A000-$BFFF BASIC 2.2
$0002-$9FFF RAMLO. VIC screen at $0400-$07FF
BASIC program & vars from $0800-$9FFF
C65 mode: $E000-$FFFF Kernel, Editor ROM code
--------- $D000-$DFFF I/O and Color Bytes (CHRROM at $29000)
$C000-$CFFF Kernel Interface, DOS ROM overflow area
$8000-$BFFF BASIC 10.0 Graphics & Sprite ROM code
$2000-$7FFF BASIC 10.0 ROM code
$0002-$1FFF RAMLO. VIC screen at $0800-$0FFF
BASIC prgs mapped from $02000-$0FF00
BASIC vars mapped from $12000-$1F7FF
C65 DOS mode: $E000-$FFFF Kernel, Editor ROM code
------------- $D000-$DFFF I/O (CIA's mapped out), Color Bytes
$C800-$CFFF Kernel Interface
$8000-$C3FF DOS ROM code
$2000-$7FFF (don't care)
$0000-$1FFF DOS RAMHI
C65 Monitor: $E000-$FFFF Kernel, Editor ROM code
------------ $D000-$DFFF I/O and Color Bytes
$C000-$CFFF Kernel Interface
$8000-$BFFF (don't care)
$6000-$7FFF Monitor ROM code
$0002-$5FFF RAMLO
It's done this way for a reason. The CPU MAPPER restricts the
programmer to one offset for each 32Kbyte half of a 64Kbyte segment.
For one chunk of ROM to MAP in another chunk with a different offset,
it must do so into the other half of memory from which it is
executing. The OS does this by never mapping the chunk of ROM at
$C000-$DFFF, which allows this chunk to contain the Interface/MAP code
and I/O (having I/O in context is usually desirable, and you can't map
I/O anyhow). The Interface/MAP ROM can be turned on and off via VIC
register $30, bit 5 (ROM @ $C000), and therefore does not need to be
mapped itself. Generally, OS functions (such as the Kernel, Editor,
and DOS) live in the upper 32K half of memory, and applications such
as BASIC or the Monitor) live in the lower 32K half. For example,
when Monitor mode is entered, the OS maps out BASIC and maps in the
Monitor. Each has ready access to the OS, but no built-in access to
each other. When a DOS call is made, the OS overlays itself with the
DOS (except for the magical $C000 code) in the upper 32K half of
memory, and overlays the application area with DOS RAM in the lower
32K half of memory.
1.5.4. C65 System I/O Memory Map
+-------------+
$DF00 | I/O-2 | EXTERNAL I/O SELECT
$DE00 | I/O-1 | EXTERNAL I/O SELECT
+-------------+
$DD00 | CIA-2 | SERIAL, USER PORT
$DC00 | CIA-1 | KEYBOARD, JOYSTICK, MOUSE CONTROL
+-------------+
$D800 | COLOR NYB | COLOR MATRIX (*FROM $1F800-$1FFFF)
+-------------+
$D700 | DMA | *DMA CONTROLLER
+-------------+
$D600 | UART | *RS-232, FAST SERIAL, NEW KEY LINES
+-------------+
$D420 | SID (L) | AUDIO CONTROLLER (LEFT)
$D400 | SID (R) | AUDIO CONTROLLER (RIGHT)
+-------------+
$D300 | BLU PALETTE |
$D200 | GRN PALETTE | *COLOR PALETTES (NYBBLES)
$D100 | RED PALETTE |
+-------------+
$D0A0 | REC | *RAM EXPANSION CTRL (OPTIONAL)
+-------------+
$D080 | FDC | *DISK CONTROLLER
+-------------+
$D000 | VIC-4567 | VIDEO CONTROLLER
+-------------+
.
.
.
+-------------+
$0000 | 4510 | MEMORY CONTROL FOR C64 MODE
+-------------+ (this register is actually in
the VIC-4567 in the C65)
*NOTE: VIC must be in "new" mode to address these devices
2.0. C65 System Hardware
2.1.1. Keyboard Layout
+----+ +----+----+----+----+ +----+----+----+----+ +----+----+----+----+
|RUN | |ESC |ALT |ASC | NO | | F1 | F3 | F5 | F7 | | F9 | F11| F13|HELP|
|STOP| | | |DIN |SCRL| | F2 | F4 | F6 | F8 | | F10| F12| F14| |
+----+ +----+----+----+----+ +----+----+----+----+ +----+----+----+----+
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
| <- | ! | " | # | $ | % | & | ' | ( | ) | | | | |CLR |INST|
| | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | + | - | � |HOME|DEL |
+----+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+----+
| TAB | | | | | | | | | | | | | � | RSTR |
| | Q | W | E | R | T | Y | U | I | O | P | @ | * | ^ | |
+----+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+------+
|CTRL|SHFT| | | | | | | | | | [ | ] | | RETURN |
| |LOCK| A | S | D | F | G | H | J | K | L | : | ; | = | |
+----+----+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+----+----+----+
| C= | SHIFT | | | | | | | | < | > | ? | SHIFT|CRSR|
| | | Z | X | C | V | B | N | M | , | . | / | | UP |
+----+-------+-+--+----+----+----+----+----+----+----+----+-+--+-+----+----+----+
| SPACE | |CRSR|CRSR|CRSR|
| | |LEFT|DOWN|RITE|
+--------------------------------------------+ +----+----+----+
Notes:
1/ The cursor keys are special -- the shifted cursor keys appear as
separate keys, but in actuality pressing them generates a SHIFT
plus the normal cursor code, making them totally compatible with,
and therefore functional in, C64 mode.
2/ There are a total of 77 keys, two of which are locking keys.
3/ The NATIONAL keyboards are similar, and their layout and operation
is identical to their C128 implementation.
2.1.2. Keyboard Matrix
+-----+-----+-----+-----+-----+-----+-----+-----+-----+ +-----+
| C0 | C1 | C2 | C3 | C4 | C5 | C6 | C7 | C8 | | GND |
|PIN20|PIN19|PIN18|PIN17|PIN16|PIN15|PIN14|PIN13|PIN-4| |PIN-1|
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ +--+--+
| | | | | | | | | |
| | | | | | | | | |
V V V V V V V V V |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ |
| R0 |<----+ INS | # | % | ' | ) | + | � | ! | NO | |
|PIN12| | DEL | 3 | 5 | 7 | 9 | | | 1 | SCRL| |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ |
| R1 |<----+ RET | W | R | Y | I | P | * | <-- | TAB | |
|PIN11| | | | | | | | | | | |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ |
| R2 |<----+ HORZ| A | D | G | J | L | ] | CTRL| ALT | |
|PIN10| | CRSR| | | | | | ; | | +----------+ |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ | |
| R3 |<----+ F8 | $ | & | { | 0 | - | CLR | " | HELP| | |
|PIN-9| | F7 | 4 | 6 | 8 | | | HOM | 2 | | | |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ | |
| R4 |<----+ F2 | Z | C | B | M | > |RIGHT|SPACE| F10 | | |
|PIN-8| | F1 | | | | | . |SHIFT| BAR | F9 +--------+ | |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ | | |
| R5 |<----+ F4 | S | F | H | K | [ | = | C= | F12 | | | |
|PIN-7| | F3 | | | | | : | | | F11 | | | |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ | | |
| R6 |<----+ F6 | E | T | U | O | @ | � | Q | F14 | | | |
|PIN-6| | F5 | | | | | | ^ | | F13 | | | |
+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+ | | |
| R7 |<----+ VERT|LEFT | X | V | N | < | ? | RUN | ESC +------+ | | |
|PIN-5| | CRSR|SHIFT| | | | , | / | STOP| +--+ | | | |
+-----+ +-+-+-+--+--+-----+-----+-----+-----+--+--+-----+-----+ | | | | |
| | | | | | | | |
| | | +------------+ | | | | |
| +-------------------------------------------+ | | | | | |
| | | | | | | | |
| +--+--+ / (LOCKING) | | | | | | |
| |SHIFT+----+ +------------------------------------+ | | | |
| | LOCK| | | | | | |
| +-----+ | | | | | |
| +-------------+ | | | | | |
+--+--+ | C0+--+ | | | | |
|CRSR +------------+-----------+ C6+------+ | | | |
| UP | K1 PIN-21 | | | | | |
+--+--+ | 4066 R7+---------------+ | | |
| | DECODER R4+-----------------+ | |
+--+--+ | | | |
|CRSR +------------+-----------+ R2+-------------------+ |
|LEFT | K2 PIN-22 | | |
+-----+ +-------------+ |
|
+-----+ +-----+ / |
| NMI | <---------+RESTR+----+ +-------------------------------------------------+
|PIN-3| | | |
+-----+ +-----+ |
|
|
+-----+ +-----+ / (LOCKING) |
| R8 | <---------+CAPS +----+ +-------------------------------------------------+
|PIN-2| |LOCK |
+-----+ +-----+
Keyboard Notes:
1/ The 64 keys under C0 through C7 occupy the same matrix position as
in the C/64, as does the RESTORE key. Including SHIFT-LOCK, there
are 66 such keys.
2/ The extended keyboard consists of the 8 keys under the C8 output.
Counting the CAPS-LOCK key, there are 9 new keys. The C/64 does not
scan these keys.
3/ The new CURSOR LEFT and CURSOR UP keys simulate a CURSOR plus RIGHT
SHIFT key combination.
4/ The keyboard mechanism will be mechanically similar to that of the
C128.
2.2. Form Factor
EXPANSION SERIAL USER PORT STEREO RGBA RF COMPOSITE FAST DISK
PORT BUS (PARALLEL) L R VIDEO VIDEO VIDEO PORT
######### #### ######### # # ##### ### ##### ####
|~ ~~~ ~~~ ~~~~ ~~~~ ~~~~ ~~~~ ~~~~ ~~~~~ ~~|
# |
# POWER CONNECTOR |
| +------------------+
## POWER SWITCH | |
| | |
# | |
# CONTROL PORT #2 | |
# | 3.5" |
| +--------------------------+ | |
# | | | DISK DRIVE |
# CONTROL PORT #1 | | | |
# | RAM EXPANSION (BOTTOM) | | |
| | | | |
## RESET | | | EJECT |
| +--------------------------+ +------------+---+-+
| +---+ |
| |
+---------------------------------------------------------------------------+
NOTES:
1. Dimensions: about 18" wide, 8" deep, 2" high.
2. Disk unit faces forward.
2.3. The CSG 4510 Microcontroller Chip
2.3.1. Description
This specification describes the requirements for a single chip
8-bit microcontroller unit fabricated in 2U CMOS double-metal
technology for high speed and low power consumption.
The IC is a fully static device that contains an enhanced 6502
microprocessor (65CE02), four independent 16-bit interval timers/two
24-hour (AM/PM) time of day clocks each with programmable alarm,
full-duplex serial I/O (UART) channel with programmable baud rate
generator, built-in memory map function to access up to 1 megabyte of
memory, two 8-bit shift registers for synchronous serial I/O, and 30
individually programmable I/O lines.
2.3.2. Configuration
This IC device shall be configured in a standard, 84-pin plastic
chip carrier package. [*** Pinout below will change for 4510R5 ***]
A A A F S C S C S V V C C R E R I N R T T
2 1 0 L R N P N P C S O A E X S R M X X E
A Q T 1 T 2 C S L P S T T Q I D D S
G I 1 2 8 S E R R * * T
2 N L T * *
* * K *
1 1 8 8 8 8 8 7 7 7 7 7
1 0 9 8 7 6 5 4 3 2 1 4 3 2 1 0 9 8 7 6 5
A3 12 +---------------------------------------+ 74 C7MHZ
A4 13 | | 73 SRQDAT
A5 14 | | 72 SRQCLK
A6 15 | | 71 SRQATN
A7 16 | | 70 PA2
A8 17 | | 69 COL7
A9 18 | | 68 COL6
A10 19 | | 67 COL5
A11 20 | | 66 COL4
A12 21 | | 65 COL3
A13 22 | CSG 4510 | 64 COL2
A14 23 | | 63 COL1
A15 24 | | 62 COL0
A16 25 | | 61 ROW7
A17 26 | | 60 ROW6
A18 27 | | 59 ROW5
A19 28 | | 58 ROW4
PSYNC 29 | | 57 ROW3
AEC 30 | | 56 ROW2
DMA* 31 | | 55 ROW1
NOIO 32 +---------------------------------------+ 54 ROW0
3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 5 5 5 5
3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
N D D D D D D D D V P R P P P P P P P P P
O B B B B B B B B C H / B B B B B B B B C
M 7 6 5 4 3 2 1 0 C O W 0 1 2 3 4 5 6 7 2
A
P
2.3.3. Functional Description
2.3.3.1. Pin Description
PIN PIN SIGNAL
NAME NUMBER DIRECTION DESCRIPTION
---- ------ ---------
VSS 1 IN This is the power ground signal (0 volts).
VCC 2,42 IN This is the power supply signal (+5 volts).
SPB, 3 I/O The SPA and SPB signals are open-drain
SPA 5 I/O and bidirectional, each with a 3Kohm
(min.) passive pull-up. The SPA and SPB
signals are the data lines used by the
two 8-bit synchronous serial port
registers. In input mode, SPA and SPB are
clocked into the device on the rising
edge of the CNTA and CNTB clocks,
respectively. In the output mode, SPA and
SPB change on the falling edge of the
CNTA and CNTB clocks, respectively.
CNTB, 4 I/O The CNTA and CNTB signals are open-drain
CNTA 6 I/O and bidirectional, each with a 3K ohm
(min.) passive pull-up. These pins are
internally synchronized to the PH0 clock
and then used to clock the synchronous
serial registers, in input mode. In
output mode, each pin will reflect the
clock signal derived from the
corresponding timer.
FLAGA/ 1 I/O The FLAGA/ and FLAGB/ inputs are negative
FLAGB/ 8 IN edge sensitive input signals. A passive
pull-up (3Kohm min.) is tied on each of
these pins. They are internally
synchronized to the PH0 clock and are
used as general purpose interrupt
inputs. Any negative transition on either
of these signals will cause the device to
start an interrupt sequence, provided
that the proper bit is set in each of the
interrupt mask registers. The device-will
drop the IRQ/ line to indicate that an
interrupt sequence is underway.
*** When the FAST SERIAL MODE is enabled the CNTA, SPA and ***
*** FLAGA/ lines will not function as described above. See ***
*** section 2.5.6. for FAST SERIAL MODE description. ***
A0-A19 9 thru 28 I/O Address Bus - This is a 20 bit bi-directional
bus with tri-state outputs. The output of each
address line is TTL compatible, capable of
driving two standard TTL loads and 55 pf. When
the AEC or DMA/ line goes low, the bus goes
tri-state. If AEC only is low, A17, A18 and A19
will each reflect the state of the A16 line.
During an I/O access (IO/ is low), A0-A3, A8 and
A9 are used to select an internal I/O register.
If AEC is high, the bus will be driven by the
CPU and A16-A19 will point to a mapped memory
location (if MAP/ is low). If memory is not
mapped (MAP/ is high), A16-A19 will be low.
PSYNC 29 OUT This output line is provided to identify those
cycles in which the microprocessor is doing an
OP CODE fetch. The PSYNC line goes high during
PHI of an OP CODE fetch and stays high for the
remainder of that cycle. If AEC or DMA/ is low
during the rising edge of PHI, in which pulse
PSYNC went high, the processor will stop in its
current state and will remain, in the state until
either AEC or DMA/ goes high. In this manner,
the SYNC signal can be used to control either
the AEC or DMA/ line to cause single instruction
execution.
AEC 30 IN This input signal is the Address Enable Control
line. When high, the address bus, R/W are
valid. When low, the address bus, R/W and MAP/
are in a high-impedance state except for A17,
A18 and A19 each of which will be connected to
the A16 line.
DMA/ 31 IN This signal is connected to a 3K passive pull-
up. When this signal is low the address bus
and R/W will be tri-stated. This will allow
external DMA devices to assume control of the
system bus lines.
(READY) Internal Signal This signal is generated internally via the
AEC and DMA/ lines. The READY signal goes high
when both AEC and DMA/ are high. It goes low
if either AEC or DMA/ goes low. The READY
signal allows the user to single-cycle the
microprocessor on all cycles including write
cycles. A low state on either DMA/ or AEC
during the rising transition of phase one (PHI)
will deassert the READY line and halt the
micro processor with the output address lines
holding the current address. This feature allows
microprocessor interfacing with low speed memory
as well as fast (max 2 cycle) Direct Memory Access
(DMA).
IO/ 32 IN This input signal is used to select the internal
registers of the device, provided memory is not
being mapped by the CPU.
MAP/ 33 OUT This signal is passively pulled-up (3 Kohm)
whenever DMA/ or AEC is pulled low.
This output signal is used to indicate whether
or not memory is being mapped by the device.
If the CPU is addressing a mapped memory region
the MAP/ line will go low and will inhibit the
IO/ line from selecting an internal register.
If the CPU is not mapping memory the MAP/ line
will be-high and A16-A19 will be kept low.
DB7-DB0 34 thru 41 I/O D0-D7 form an 8 bit bi-directional data bus for
data exchanges to and from the internal CPU (the
65CE02) and the device internal registers. It is
also used to communicate with external peripheral
devices. The output buffers are capable
of driving two standard TTL loads and 55pf.
R/W 43 I/O This signal is generated by the CPU to control
the direction of data transfers on the data bus.
This line is high except when the CPU is writing
to memory, an internal I/O register or an
external device. When the AEC or DMA/ signal is
low, the R/W becomes tri-state.
PH0 44 IN This clock is a TTL compatible input used for.
internal device operation and as a timing
reference for communicating with the system
data bus. Two internal clocks are generated by
the device; phase two (PH2) is in phase with PH0,
and phase one (PH1) is 180 degrees out of phase
with PH0.
PC/ 53 OUT This output line is a strobe signal and is
Centronics interface compatible. The signal goes
low following a read or write access of PORT D.
PRD0-PRD7 45 thru 52 I/O These are three 8-bit ports with each of their
PRB0-PRB7 54 thru 61 I/O lines having a passive pull-up (min. 3K ohm)
PRA0-PRA7 62 thru 69 I/O as well as active pull-up and pull-down
transistors. Each individual port line may be
programmed to be either input or output.
PRC2 70 I/O This line corresponds to PORT C, bit 2.
It has passive pull-up (min. 3k ohm) as
well as active pull-up and pull-down
transistors. The line can be configured
as input or output. PRC2 becomes the
external shift register clock when the
UART is configured to operate in the
synchronous mode, otherwise PRC2
operates as normal.
PRC3 71 OUT This signal is an open drain output with a
passive pull-up (1K ohm min). It corresponds to
bit 3 of PORT C. When this port bit is set as
an input, the PRC3 line is driven low; reading
the port bit will give a high. If configured as
an output, reading this port bit will not give
the-status of the PRC3 line but the value
previously written on the PORT C data reg. bit 3.
PRC46 72 I/O This is an open drain bi-directional signal with
a passive pull-up (1K ohm min). Bit 6 of PORT C
is always configured as an input; the bit will
give the status of the PRC46 line anytime the
the port is read, regardless of what is written
in the data direction register.
If bit 4 of PORT C is set as an input, the PRC46
line will be pulled low; reading the port bit
will give a high. If bit 4 is configured as
an output, PRC46 will be pulled low if bit 4 in
the port data register is high, otherwise the
PRC46 line will float to a high.
PRC57 73 I/O This is an open drain bi-directional signal with
a passive pull-up (1K ohm min). Bit 7 of PORT C
is always configured as an input; the bit will
give the status of the PRC57 line anytime the
the port is read, regardless of what is written
in the data direction register.
If bit 5 of PORT C is set as an input, the PRC57
line will be pulled low; reading the port bit
will give a high. If bit 5 is configured as
an output, PRC57 will be pulled low if bit 5 in
the port data register is high, otherwise the
PRC57 line will float to a high.
PRE0,PRE1 83, 84 I/O This a 2-bit port with each line having a
passive pull-up (min. 3K ohm) as well as active
pull-up and pull-down transistors. Each indi-
vidual port line may be programmed to be eithi.
input or output.
BAUDCLK 74 IN This Input is a 7MHz clock used to drive the
UART Baud Rate Generator, and is assumed to
be synchronous with the PHO clock. This clock
is also divided down to 1MHz to drive the
interval timers, and down to 10Hz to drive the
TOD timers. This clock is also used to time out
the FOR and RESTORE (RSTR*) circuits.
TEST 75 IN When this input goes to a high state, the device
will operate in a test mode. The test mode will
allow the BAUDCLK dividers to be initialized and
the TOD and interval timers to be driven
directly by the BAUDCLK clock, bypassing all the
dividers.
TXD 76 OUT This is the UART transmit data output line.
The LSB of the Transmit Data Register is the
first data bit transmitted. The data transmission
rate (baud rate) is determined by the
value written to the Baud Rate Timer latches.
RXD 77 IN This is the UART receive data input line and
is connected to a passive pull-up (1K ohm min)
The first data bit received is loaded into the
LSB of the Receive Data Register. The receiver
data rate must be the same as that determined
by the value written to the Baud Rate Timer
latches.
NMI/ 78 I/O The NMI/ pin is an open drain bi-directional
signal. A passive pull-up (3K ohms minimum) is
tied on this pin, allowing multiple NMI/ sources
to be tied together. A negative transition on
this pin requests a non-maskable interrupt
sequence to be generated by the microprocessor.
The interrupt sequence will begin with the first
PSYNC after a multiple-cycle opcode. NMI/ inputs
cannot be masked by the processor status
register I flag. The two program counter bytes
PCH and PCL, and the processor status register
P, are pushed onto the stack. Then the program
counter bytes PCL and PCH are loaded from memory
addresses FFFA and FFFB/ respectively.
NOTE: Since this interrupt is non-maskable,
another NMI/ can occur before the first is
finished. Care should be taken to avoid this.
The NMI/ line is normally off (high impedance)
and the device will activate it low as described
in the functional description. AEC and DMA/ must
be high for any interrupt to be recognized.
IRQ/ 79 I/O The Interrupt Request line (IRQ/) is an open
drain bi-directional signal. A passive pull-
up (3K Ohms minimum) is tied on this pin,
allowing multiple IRQ/ sources to be connected
together. This pin is sampled during PH2 and
when a negative transition is detected an inter-
rupt will be activated, only if the mask flag
(I) in the status register is low. The inter-
rupt sequence will begin with the first PSYNC
after a multiple-cycle opcode. The two program
counter bytes PCH and PCL, and the processor
status register P, are stored-onto the stack;
the interrupt mask flag is set high so that no.
further IRQ/'s may occur. At the end of this
cycle, the program counter low byte (PCL) will
be loaded from address FFFE/ and the high byte
(PCH) from FFFF, thus transferring program
control to the vector located at this addresses.
The IRQ/ line is normally off (high impedance)
and the device will activate it low as described
in the functional descriptioni AEC and DMA/ must
be high for any interrupt to be recognized.
RESTR/ 80 IN This input is tied to a 3K ohm (min.) passive
pull-up. A bounce eliminator circuit is used
on this pin to remove any bounce during its
falling transition, if the pin is tied to a
contact closure. If the device sees a negative
transition on this pin, it will immediately
assert the NMI/ line to start a Non-Maskable In-
terrupt sequence. The device will ignore any
subsequent transitions on the RESTR/ line until
4.2ms has elapsed, at which time the NMI/ line
is deasserted.
EXTRST/ 81 OUT This output is an open drain output with a min.
1K ohm pull-up. This pin will only go to a low
state during power-up, and will stay low until
.9 seconds after VDD has reached its operating
voltage.
RESET/ 82 I/O The Reset line (RESET/) is an open drain bi-
directional signal. A passive pull-up (1K ohm
minimum) is tied on this pin, allowing any ex-
ternal source to initialize the device. A low
on RESET/ will instantly initialize the internal
65CE02 and all internal registers. All port
pins are set as inputs and port registers to
zero (a read of the ports will return all highs
because of passive pull-ups); all timer control
registers are set to zero and all timer latches
to ones. All other registers are reset to zero.
During power-up RESET/ is held low and will go
high .9 seconds after VDD reaches the operating
voltage. If pulled low during operation, the
currently executing opcode will be terminated.
The B and 2 registers will be cleared. The stack
pointer will be set to "byte" mode, with the
stack page set to page 1. The processor status
bits E and I will be set. When the high transition
is detected/the reset sequence begins
on the CPU cycle. The first four cycles of the
reset sequence do nothing. Then the program
counter bytes PCL and PCH are loaded from memory
addresses FFFC and FFFD, and normal program
execution begins.
2.3.3.2. 4510R3 Timing Description
+---+ +---+
-----------| |-----------------------------| |---------AEC, DMA
+---+ +---+
TAES---| + |--TAEH |----- TPWH -----|
-------------+ +----------------+
| | | PH0
+----------------+ +-----------
|----- TPWL -----|
TAIS--| |-- --| |--TAIH
-----------------+ +---------------------+ NOIO,R/W
+----------+ VALID +-------- A0-A19/NOMAP
-----------------+ +---------------------+ (INPUT)
---|TAOS |--- ---| |--TAOH
----------------+ +-----------------------------+ +---- PSYNC,R/W
+---+ VALID +---+ A0-A19/NOMAP
----------------+ +-----------------------------+ +---- (OUTPUT)
TDIS|- -+- -|TDIH |--TDOS--| |- -|TDOH
+-------+ +-----------+
--------+ VALID +-----------------------+ VALID +------ D0-D7
+-------+ +-----------+
------+ +---------
| | AEC, DMA
+---------------+
--| |--TAZ --| |--TZA
--------+ +-------
ON +---------------+ ON D0-D7,R/W/A0-A15(AEC, DMA)
--------+ +-------A16-A19 (DMA)
|--- TCH ---|
-------+ +-----------+
| | | C7MHZ
+---------+ +------
|---TCL---| --| |--TCCL
---------------------------+
| PH0
+--------
Param Description MIN TYP MAX
----- ------------------------- --- --- ---
Tpwh PH0 clock high time 65 135 -
Tpwl PH0 clock low time 65 135 -
Taes AEC, DMA setup to PH0 falling 30 - -
Taeh AEC, DMA hold from PH0 falling 10 - -
Tais address input setup to PH0 rising 20 - -
Tain address input hold from PH0 falling 10 - -
Taos address output setup from PH0 falling - - 50
Taoh address output hold from PH0 falling 15 - -
Tdis data input setup to PH0 falling 40 - -
Tdih data input hold from PH0 falling 10 - -
Tdos data output setup from PH0 rising - - 50
Tdoh data output hold from PH0 falling 30 - -
Taz address off from AEC or DMA falling 0 15 20
Tza address on from AEC and DMA rising 15 - 30
Tch C7MHZ clock high time 65 - -
Tcl C7MHZ clock low time 65 - -
TccL C7MHZ delay from PH0 0 - 50
2.3.3.3. Register Description
This device contains a total of 41 I/O peripheral registers which
can be accessed after the following conditions are met. In a an access
cyclethe device must be in a non-mapped mode (MAP/ line is not
asserted), the IO/ line must be in an active low state and the AO-A3,
A8 and A9 address-lines must contain the valid address of the register
to be accessed. In addition the state of the R/W line will indicate
whether a read (R/W is "high") write (R/W is "low") cycle is under
way.
A9 A8...A3 A2 A1 A0 HEX ADD REG SYMBOL REGISTER NAME
+--------------------+-------+-----------+---------------------------+
| 0 0 0 0 0 0 | 0X0 | PRA | Peripheral Data Reg A |
| 0 0 0 0 0 1 | 0X1 | PRB | Peripheral Data Reg B |
| 0 0 0 0 1 0 | 0X2 | DDRA | Data Direction Reg A |
| 0 0 0 0 1 1 | 0X3 | DDRB | Data Direction Reg B |
| 0 0 0 1 0 0 | 0X4 | TA LO | Timer A Low Register |
| 0 0 0 1 0 1 | 0X5 | TA HI | Timer A High Register |
| 0 0 0 1 1 0 | 0X6 | TB LO | Timer B Low Register |
| 0 0 0 1 1 1 | 0X7 | TB HI | Timer B High Register |
| 0 0 1 0 0 0 | 0X8 | TODATS | TODA 10ths Sec Register |
| 0 0 1 0 0 1 | 0X9 | TODAS | TODA Seconds Register |
| 0 0 1 0 1 0 | 0XA | TODAM | TODA Minutes Register |
| 0 0 1 0 1 1 | 0XB | TODAH | TODA Hours-AM/PM Reg. |
| 0 0 1 1 0 0 | 0XC | SDRA | SERIALA Data Register |
| 0 0 1 1 0 1 | 0XD | ICRA | INTERRUPTA Control Reg. |
| 0 0 1 1 1 0 | 0XE | CRA | Control Register A |
| 0 0 1 1 1 1 | 0XF | CRB | Control Register B |
| 0 1 0 0 0 0 | 1X0 | PRC | Peripheral Data Reg. C |
| 0 1 0 0 0 1 | 1X1 | PRD | Peripheral Data Reg. D |
| 0 1 0 0 1 0 | 1X2 | DDRC | Data Direction Reg C |
| 0 1 0 0 1 1 | 1X3 | DDRD | Data Direction Reg D |
| 0 1 0 1 0 0 | 1X4 | TC LO | Timer C Low Register |
| 0 1 0 1 0 1 | 1X5 | TC HI | Timer C High Register |
| 0 1 0 1 1 0 | 1X6 | TD LO | Timer D Low Register |
| 0 1 0 1 1 1 | 1X7 | TD HI | Timer D High Register |
| 0 1 1 0 0 0 | 1X8 | TODBTS | TODB 10ths of Sec Reg. |
| 0 1 1 0 0 1 | 1X9 | TODBS | TODB Seconds Register |
| 0 1 1 0 1 0 | 1XA | TODBM | TODB Minutes Register |
| 0 1 1 0 1 1 | 1XB | TODBH | TODB Hours-AM/PM Reg. |
| 0 1 1 1 0 0 | 1XC | SDRB | SERIALB Data Register |
| 0 1 1 1 0 1 | 1XD | ICRB | INTERRUPTB Control Reg. |
| 0 1 1 1 1 0 | 1XE | CRC | Control Register C |
| 0 1 1 1 1 1 | 1XF | CRD | Control Register D |
| 1 0 0 0 0 0 | 2X0 | DREG | Receive/Transmit Data Reg|
| 1 0 0 0 0 1 | 2X1 | URSR | UART Status Register |
| 1 0 0 0 1 0 | 2X2 | URCR | UART Control Register |
| 1 0 0 0 1 1 | 2X3 | BRLO | Baud Rate Timer LO Reg. |
| 1 0 0 1 0 0 | 2X4 | BRHI | Baud Rate Timer HI Reg. |
| 1 0 0 1 0 1 | 2X5 | URIEN | UART IRQ/NMI Enable Reg. |
| 1 0 0 1 1 0 | 2X6 | URIFG | UART IRQ/NMI Flag Reg. |
| 1 0 0 1 1 1 | 2X7 | PRE | Peripheral Data Reg. E |
| 1 0 1 0 0 0 | 2X8 | DDRE | Data Direction E |
| 1 0 1 0 0 1 | 2X9 | FSERIAL | Fast Serial Bus Control |
+--------------------+-------+-----------+---------------------------+
REGISTER ADDRESS ALLOCATION
TABLE 1
The functional description of the memory mapper follows in section
2.3.4. The Fast Serial register is described in section 2.3.5.6.
2.3.3.3.1. REGISTER BIT ALLOCATION
R/W REG NAME D7 D6 D5 D4 D3 D2 D1 D0
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |0X0| PRA | PA7 | PA6 | PA5 | PA4 | PA3 | PA2 | PA1 | PA0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |0X1| PRB | PB7 | PB6 | PB5 | PB4 | PB3 | PB2 | PB1 | PB0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |0X2| DDRA | DPA7 | DPA6 | DPA5 | DPA4 | DPA3 | DPA2 | DPA1 | DPA0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |0X3| DDRB | DPB7 | DPB6 | DPB5 | DPB4 | DPB3 | DPB2 | DPB1 | DPB0 |
+-----+---+------+---+------+------+------+------+------+------+------+------+
| READ|0X4| TA LO| | TAL7 | TAL6 | TAL5 | TAL4 | TAL3 | TAL2 | TAL1 | TAL0 |
+-----+---+------+ T +------+------+------+------+------+------+------+------+
| READ|0X5| TA HI| I | TAH7 | TAH6 | TAH5 | TAH4 | TAH3 | TAH2 | TAH1 | TAH0 |
+-----+---+------| M +------+------+------+------+------+------+------+------+
| READ|0X6| TB LO| E | TBL7 | TBL6 | TBL5 | TBL4 | TBL3 | TBL2 | TBL1 | TBL0 |
+-----+---+------| R +------+------+------+------+------+------+------+------+
| READ|0X7| TB HI| | TBH7 | TBH6 | TBH5 | TBH4 | TBH3 | TBH2 | TBH1 | TBH0 |
+-----+---+------+---+------+------+------+------+------+------+------+------+
| | | | P | | | | | | | | |
|WRITE|0X4| TA LO| R | PAL7 | PAL6 | PAL5 | PAL4 | PAL3 | PAL2 | PALI | PAL0 |
+-----+---+------+ E +------+------+------+------+------+------+------+------+
|WRITE|0X5| TA HI| S | PAH7 | PAH6 | PAH5 | PAH4 | PAH3 | PAH2 | PAH1 | PAHO |
+-----+---+------+ C +------+------+------+------+------+------+------+------+
|WRITE|0X6| TB LO| A | PBL7 | PBL5 | PBL5 | PBL4 | P3L3 | PBL2 | PBL1 | PBL0 |
+-----+---+------+ L +------+------+------+------+------+------+------+------+
|WRITE|0X7| TB HI| E | PBH7 | PBH6 | PBH5 | PBH4 | PBH3 | PBH2 | PBH1 | PBH0 |
| | | | R | | | | | | | | |
+-----+---+------+---+------+------+------+------+------+------+------+------+
| | | | T | | | | | | | | |
| READ|0X8|TODATS| O | 0 | 0 | 0 | 0 | TA8 | TA4 | TA2 | TA1 |
+-----+---+------+ D +------+------+------+------+------+------+------+------+
| READ|0X9|TODAS | |(*) 0 | SAH4 | SAH2 | SAH1 | SAL8 | SAL4 | SAL2 | SAL1 |
+-----+---+------+ T +------+------+------+------+------+------+------+------+
| READ|0XA|TODAM | I |(*) 0 | MAH4 | MAH2 | MAH1 | MAL8 | MAL4 | MAL2 | MAL1 |
+-----+---+------+ M +------+------+------+------+------+------+------+------+
| READ|0XB|TODAH | E | APM | 0 | 0 | HAH | HAL8 | HAL4 | HAL2 | HAL1 |
+-----+---+------+ +------+------+------+------+------+------+------+------+
| | | | | (*) IN TEST MODE: WILL READ DIVIDER STAGE OUTPUTS |
+-----+---+------+---+------+------+------+------+------+------+------+------+
| | | | T | | | | | | | | |
|WRITE|0X8|TODATS| 0 | 0 | 0 | 0 | 0 | TA8 | TA4 | TA2 | TA1 |
+-----+---+------+ +------+------+------+------+------+------+------+------+
|WRITE|0X9|TODAS | | 0 | SAH4 | SAH2 | SAH1 | SAL8 | SAL4 | SAL2 | SAL1 |
+-----+---+------+ L +------+------+------+------+------+------+------+------+
|WRITE|0XA|TODAM | A | 0 | MAH4 | MAH2 | MAH1 | MAL8 | MAL4 | MAL2 | MAL1 |
+-----+---+------+ T +------+------+------+------+------+------+------+------+
|WRITE|0XB|TODAH | C | APM | 0 | 0 | HAH | HAL8 | HAL4 | HAL2 | HAL1 |
| | | | H | | | | | | | | |
| | | | E | IF CRB ALARM BIT=1 , ALARM REGISTER IS WRITTEN |
| | | | S | IF CRB ALARM BIT=0 , TOD REGISTER IS WRITTEN |
+-----+---+------+---+------+------+------+------+------+------+------+------+
| R/W |0XC| SDRA | SRA7 | SRA6 | SRA5 | SRA4 | SRA3 | SRA2 | SRA1 | SRA0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| READ|0XD| ICRA | IRA | 0 | 0 | FLGA | SPA | ALRMA| TB | TA |
| | |(INT DATA)| | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
|WRITE|0XD| ICRA |AS/C~ | -- | -- | FLGA | SPA | ALRMA| TB | TA |
| | |(INT MASK)| | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |0XE| CRA | TODA | SPA | TMRA | LOADA| RUN-A| OUT-A| PRB6 |STARTA|
| | | | IN | MODE |INMODE| | MODE | MODE | ON | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |0XF| CRB |ALARM |TIMERB|INMODE| LOADB| RUN-B| OUT-B| PRB7 |STARTB|
| | | |(TODA)| CRB6 | CRB5 | | MODE | MODE | ON | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| READ|1X0| PRC | PC7 | PC6 | PC5 | PC4 | PC3 | PC2 | PC1 | PC0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |1X1| PRD | PD7 | PD6 | PD5 | PD4 | PD3 | PD2 | PD1 | PD0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |1X2| DDRC | DPC7 | DPC6 | DPC5 | DPC4 | DPC3 | DPC2 | DPC1 | DPC0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |1X3| DDRD | DPD7 | DPD6 | DPD5 | DPD4 | DPD3 | DPD2 | DPD1 | DPD0 |
+-----+---+------+---+------+------+------+------+------+------+------+------+
| READ|1X4| TC LO| | TCL7 | TCL6 | TCL5 | TCL4 | TCL3 | TCL2 | TCL1 | TCL0 |
+-----+---+------+ T +------+------+------+------+------+------+------+------+
| READ|1X5| TC HI| I | TCH7 | TCH6 | TCH5 | TCH4 | TCH3 | TCH2 | TCH1 | TCH0 |
+-----+---+------| M +------+------+------+------+------+------+------+------+
| READ|1X6| TD LO| E | TDL7 | TDL6 | TDL5 | TDL4 | TDL3 | TDL2 | TDL1 | TDL0 |
+-----+---+------| R +------+------+------+------+------+------+------+------+
| READ|1X7| TD HI| | TDH7 | TDH6 | TDH5 | TDH4 | TDH3 | TDH2 | TDH1 | TDH0 |
+-----+---+------+---+------+------+------+------+------+------+------+------+
| | | | P | | | | | | | | |
|WRITE|1X4| TC LO| R | PCL7 | PCL6 | PCL5 | PCL4 | PCL3 | PCL2 | PCL1 | PCL0 |
+-----+---+------+ E +------+------+------+------+------+------+------+------+
|WRITE|1X5| TC HI| S | PCH7 | PCH6 | PCH5 | PCH4 | PCH3 | PCH2 | PCH1 | PCH0 |
+-----+---+------+ C +------+------+------+------+------+------+------+------+
|WRITE|1X6| TD LO| A | PDL7 | PDL6 | PDL5 | PDL4 | PDL3 | PDL2 | PDL1 | PDL0 |
+-----+---+------+ L +------+------+------+------+------+------+------+------+
|WRITE|1X7| TD HI| E | PDH7 | PDH6 | PDH5 | PDH4 | PDH3 | PDH2 | PDH1 | PDH0 |
| | | | R | | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | T | | | | | | | | |
|READ |1X8|TODBTS| O | 0 | 0 | 0 | 0 | TB8 | TB4 | TB2 | TB1 |
+-----+---+------+ D +------+------+------+------+------+------+------+------+
|READ |1X9|TODBS | |(*) 0 | SBH4 | SBH2 | SBH1 | SBL8 | SBL4 | SBL2 | SBL1 |
+-----+---+------+ T +------+------+------+------+------+------+------+------+
|READ |1XA|TODBM | I | 0 | MBH4 | MBH2 | MBH1 | MBL8 | MBL4 | MBL2 | MBL1 |
+-----+---+------+ M +------+------+------+------+------+------+------+------+
|READ |1XB|TODBH | E | BPM | 0 | 0 | HBH | HBL8 | HBL4 | HBL2 | HBL1 |
| | | | R | | | | | | | | |
| | | | | (*) IN TEST MODE: WILL READ DIVIDER STAGE OUTPUT |
+-----+---+------+---+------+------+------+------+------+------+------+------+
|WRITE|1X8|TODBTS| T | 0 | 0 | 0 | 0 | TB8 | TB4 | TB2 | TB1 |
+-----+---+------+ O +------+------+------+------+------+------+------+------+
|WRITE|1X9|TODBS | D | 0 | SBH4 | SBH2 | SBH1 | SBL8 | SBL4 | SBL2 | SBL1 |
+-----+---+------+ L +------+------+------+------+------+------+------+------+
|WRITE|1XA|TODBM | A | 0 | MBH4 | MBH2 | MBH1 | MBL8 | MBL4 | MBL2 | MBL1 |
+-----+---+------+ T +------+------+------+------+------+------+------+------+
|WRITE|1XB|TODBH | C | BPM | 0 | 0 | HBH | HBL8 | HBL4 | HBL2 | HBL1 |
| | | | H | | | | | | | | |
| | | | E | IF CRD ALARM BIT=1 , ALARM REGISTER IS WRITTEN |
| | | | S | IF CRD ALARM BIT=0 , TOD REGISTER IS WRITTEN |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |1XC| SDRB | SRB7 | SRB6 | SRB5 | SRB4 | SRB3 | SRB2 | SRB1 | SRB0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
|READ |1XD| ICRB | IRB | 0 | 0 | FLGB | SPB | ALRMB| TD | TC |
| | |(INT DATA)| | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
|WRITE|1XD| ICRB |BS/C~ | -- | -- | FLGB | SPB | ALRMB| TD | TC |
| | |(INT MASK)| | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |1XE| CRC | TODB | SPB | TMRC | LOADC| RUN-C| OUT-C| PRD6 |STARTC|
| | | | IN | MODE |INMODE| | MODE | MODE | ON | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |1XF| CRD |ALARM |TIMERD|INMODE| LOADD| RUN-D| OUT-D| PRD7 |STARTD|
| | | |(TODB)| CRD6 | CRD5 | | MODE | MODE | ON | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| READ|2X0| DREG | RCV7 | RCV6 | RCV5 | RCV4 | RCV3 | RCV2 | RCV1 | RCV0 |
|(RECEIVE DATA REG) | | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
|WRITE|2X0| DREG | XMT7 | XMT6 | XMT5 | XMT4 | XMT3 | XMT2 | XMT1 | XMT0 |
|(TRANSMIT DATA REG) | | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| READ|2X1| URSR |TDONE | EMPTY| ENDT | IDLE | FRME | PRTY | OVR | FULL |
+-----+---+----------+------+------+------+------+------+------+------+------+
|WRITE|2X1| URSR | -- | -- | ENDT | IDLE | -- | -- | -- | -- |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |2X2| URCR | XMITR| RCVER| UART | MODE | CHAR LENGTH |PARITY PARITY|
| | | | EN | EN | UM1 | UM0 | CH1 CH0 | EN | EVEN |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |2X3| BRL0 | BRL7 | BRL6 | BRL5 | BRL4 | BRL3 | BRL2 | BRL1 | BRL0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |2X4| BRHI | BRH7 | BRH6 | BRH5 | BRH4 | BRH3 | BRH2 | BRH1 | BRH0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |2X5| URIEN | XDIRQ| RDIRQ| XDNMI| RDNMI| -- | -- | -- | -- |
+-----+---+----------+------+------+------+------+------+------+------+------+
| READ|2X6| URIFG | XDIRQ| RDIRQ| XDNMI| RDNMI| -- | -- | -- | -- |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |2X7| PRE | -- | -- | -- | -- | -- | -- | PE1 | PE0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |2X8| DDRE | -- | -- | -- | -- | -- | -- | DPE1 | DPE0 |
+-----+---+----------+------+------+------+------+------+------+------+------+
| R/W |2X9| FSERIAL |*DMODE|*FSDIR| -- | -- | -- | -- | -- | -- |
+-----+---+----------+------+------+------+------+------+------+------+------+
REGISTER BIT ALLOCATION
TABLE 2
2.3.4. Memory Mapper
The microprocessor core is actually a C4502R1 with some
addittional instructions, used to operate the memory mapper.
The former AUG (augment) opcode has been changed to MAP (mapper),
and the former NOP (no-operation) has been changed to EOM (end-of-
mapping-sequence).
The 4510 memory mapper allows the microprocessor to access up to
1 megabyte of memory. Here's how. The 6502 microprocessor can only
access 64K bytes of memory because it only uses addresses of 16 bit's.
The 4502 is not different, nor is the 4510. But the 4510 memory mapper
allows these addresses to be redirected to new physical addresses
to access different parts of a much larger memory, within the 64K byte
confinement window.
The 64K window has been divided into eight blocks, and two
regions, with four blocks in each region. Blocks 0 through 3 are in
the "lower" region, and blocks 4 through 7 are in the "upper" region,
as shown...
+- +-----------+FFFF
| | BLK 7 |
| +-----------+E000
| | BLK 6 |
UPPER REGION -+ +-----------+C000
| | BLK 5 |
| +-----------+A000
| | BLK 4 |
+- +-----------+8000
| | BLK 3 |
| +-----------+6000
| | BLK 2 |
LOWER REGION -+ +-----------+4000
| | BLK 1 |
| +-----------+2000
| | BLK 0 |
+- +-----------+
Each block can be programmed to be "mapped", or "non-mapped" via
bits in the mapper's "mask" registers. NON-MAPPED means, simply,
address out equals address in. Therefore, there are still only 64K
bytes of non-mapped memory. MAPPED means that address out equals
address in plus some offset. The offset is programmed via the mapper's
"offset" registers.
There are two "offset" registers. One is for the lower region, and one
is for the upper region.
The low-order 6 addresses are never mapped. The offsets are only
added to the 12 high-order addresses. This means the smallest unit you
can map to is 256 bytes, or one page.
The 4510 has an output (NOMAP) which lets the outside world know
when the processor is accessing mapped (0) or non-mapped (1) address.
This is useful for systems where you may want I/O devices to be at
fixed (non-mapped) addresses, and only memory at mapped addresses.
It is possible, and likely, to have mapped, and unmapped memory
at the same physical address. And, with offset registers set to zero,
mapped addresses will match unmapped ones. The only difference is the
NOMAP signal to tell whether the address is mapped or unmapped.
To program the mapper, the operating system must load the A, X,
Y, and Z registers with the following information, and execute a MAP
opcode.
Mapper Register Data
7 6 5 4 3 2 1 0 BIT
+-------+-------+-------+-------+-------+-------+-------+-------+
| LOWER | LOWER | LOWER | LOWER | LOWER | LOWER | LOWER | LOWER | A
| OFF15 | OFF14 | OFF13 | OFF12 | OFF11 | OFF10 | OFF9 | OFF8 |
+-------+-------+-------+-------+-------+-------+-------+-------+
| MAP | MAP | MAP | MAP | LOWER | LOWER | LOWER | LOWER | X
| BLK3 | BLK2 | BLK1 | BLK0 | OFF19 | OFF18 | OFF17 | OFF16 |
+-------+-------+-------+-------+-------+-------+-------+-------+
| UPPER | UPPER | UPPER | UPPER | UPPER | UPPER | UPPER | UPPER | Y
| OFF15 | OFF14 | OFF13 | OFF12 | OFF11 | OFF10 | OFF9 | OFF8 |
+-------+-------+-------+-------+-------+-------+-------+-------+
| MAP | MAP | MAP | MAP | UPPER | UPPER | UPPER | UPPER | Z
| BLK7 | BLK6 | BLK5 | BLK4 | OFF19 | OFF18 | OFF17 | OFF16 |
+-------+-------+-------+-------+-------+-------+-------+-------+
After executing the MAP opcode, all interrupts are inhibited.
This is done to allow the operating system is complete a mapping
sequence without fear of getting an interrupt. An interrupt occurring
before the proper stack-pointer is set will cause return address data
to be written to an undesired area.
Upon completing the mapping sequence, the operating system must
remove the interrupt inhibit by executing a EOM (formerly NOP) opcode.
Note that application software may execute NOPs with no effect.
2.3.5. Peripheral Control Functions
2.3.5.1. I/O Ports
Ports A, B and D each consist of an 8-bit Peripheral Data
Register (PR) and an 8-bit Data Direction Register (DDR). Port E
consists of a 2-bit PR and DDR registers. If a bit in the DDR is set
to one, the corresponding bit in the PR is an output, if a DDR bit is
set to a zero, the corresponding PR bit is defined as an input. On a
READ, the PR bit reflects the information present on the actual port
pins (PRA0-PRA7, PRB0-PRB7, PRC2, PRD0-PRD7, PRE0-PRE1) for both input
and output bits. All ports have passive pull-up devices as well as
active pull-ups, providing both CMOS and TTL compatibility.
In addition to normal I/O operation, PRB6, PRB7, PRD6 and PRD7 also
provide timer output functions (refer to Control Register section,
2.5.8.).
Only bit PC2 and DPC2 of PORT C meet the above description. The
other bits function as described in the following.
PC0,PC1 These signals are simply a register bits. When read, they
will reflect the value previously written to the PRC
register.
PC4 This bit is a "high" if it's configured as input (DPC4 is a
"low"). If configured as output (DPC4 is a "high"), the bit
will reflect its previous written value when PORT C is
read. Then the PRC46 pin is pulled "low" if PC4 is "high";
otherwise, PRC46 is pulled-up through passive resistor.
PC5 This bit is a "high" if it's configured as input (DPC5 is a
"low"). If configured as output (DPC5 is a "high"), the bit
will reflect its previous written value when PORT C is
read. Then the PRC57 pin is pulled "low" if PC5 is "high";
otherwise, PRC57 is pulled-up through passive resistor.
PC6,PC7 These bits are always configured as inputs. When PORT C
(PRC) is read, PC6 and PC7 will reflect the values on the
PRC46 and PRC57 pins, respectively.
2.3.5.2. Handshaking
Handshaking on data transfers can be accomplished using the PC/
output pin and either the FLAGA/ or FLAGB/ input pin. The PC/ line
will go low and stay low for two cycles, two cycles after a read or
write to PORT D. This is required to meet Centronics Parallel
Interface specs. The PC/ line can be used to indicate "data ready" at
PORT D or "data accepted" from PORT D. Handshaking on 16-bit data
transfers (using either PORT A or B and then PORT D) is possible by
always reading or writing PORT A or PORT B first. The FLAG/ lines are
negative edge sensitive inputs which can be used for receiving the PC/
output from other 4510 devices, or as general purpose interrupt
inputs. A negative transition on FLAGA/ or FLAGB/ will set the FLAGA
or FLAGB interrupt bits, respectively.
2.3.5.3. Interval Timers (Timer A, Timer B, Timer C, Timer D)
Each interval timer consists of a 16-bit read-only Timer Counter
and a 16-bit write-only Timer Latch (prescaler). Data written to the
timer are latched in the Timer Latch, while data read from the timer
are the present contents of the Timer Counter. The timers can be used
independently or linked in pairs for extended operations (TIMER A may
be linked with Timer B; TIMER C may be linked with TIMER D). The
various timer modes allow generation of long time delays, variable
width pulses, pulse trains and variable frequency waveforms. Utilizing
the CNT inputs, the timers can count external pulses or measure
frequency, pulse witdth and delay times of external signals. Each
timer has an associated control register, providing independent
control of the following functions (see bits functional description in
section 2.5.8 below):
Start/Stop
Each timer may be started or stopped by the microprocessor at
any time by writing to the START/STOP bit of the corresponding control
register (CRA, CRB, CRB or CRC).
PRB, PRD On/Off
Control bits allow any of the timer outputs to appear on a PORT
B or PORT D output line (PRB6 for TIMER A, PRB7 for TIMER B, PRD6 for
TIMER C and PRD7 for TIMER D). Note that this function overrides the
DDRB control bit and forces the appropriate PB or PC line to be an
output.
Toggle/Pulse
Control bits select the ouputs applied to PORT B and PORT D. On
every timer underflow the ouput can either toggle or generate a single
positive pulse of one cycle duration. The Toggle output is set high
whenever the appreciate timer is started and is set low by RESET/.
One-Shot/Continuous
Control bits select-either timer mode. In one-shot mode, the
timer will count down from the latched value to zero, generate an
interrupt, reload the latched value, then stop. In continuous mode,
the timer will count from the latched value to zero, generate an
interrupt, reload the latched value and repeat the procedure
continuously.
Force Load
A strobe bit allows the timer latch to be loaded into the timer
counter at any time, whether the timer is running or not.
Input Mode
Control bits allow selection of the clock used to decrement the
timer. TIMER A or TIMER C can count C1MHZ clock pulses or external
pulses applied to the CNTA or CNTB, respectively. The C1MHZ clock is
obtained after internally dividing the C7MHZ by a factor of seven.
TIMER B can count C1MHZ clock pulses, external pulses applied to
the CNTA input, TIMER A underflow pulses or TIMER A underflow pulses
while the CNTA pin is held high.
TIMER D can count C1MHZ clock pulses, external pulses applied to
the CNTB input, TIMER C underflow pulses or TIMER C underflow pulses
while the CNTB pin is held high.
The timer latch is loaded into the timer on any timer underflow,
on a force load or following a write to the high byte of the prescaler
while the timer is stopped. If the timer is running, a write to the
high byte will load the timer latch, but not reload the counter.
2.3.5.4. Time of Day Clocks (TODA, TODB)
The TODA and TODB clocks are special purpose timers for
real-time applications. Each clock, TODA or TODB, consists of a
24-hour (AM/PM) clock with 1/10th second resolution. Each is organized
into four registers: 10ths of seconds (TODATS, TODBTS), Seconds
(TODAS, TODBS)/Minutes (TODAM, TODBM) and Hours (TODAH, TODBH). The
AM/PM flag is in the MSB of the Hours register for easy testing. Each
register reads out in BCD format to simplify conversion for driving
displays, etc. Each TOD requires a 10HZ clock input to keep accurate
timing. This 10HZ clock is generated by dividing the C7MHz clock input
by a factor of 102273 for NTSC (60Hz) applications, or a factor of
101339 for PAL (50Hz) applications. The divider ratio is selected by
the TODA IN and the TODB IN bits of the Control Registers, CRA and
CRC, respectively (see 2.5.8).
In addition to time-keeping, a programmable ALARM is provided
for generating an interrupt at the desired time, from either of the
TOD clocks. The ALARM registers registers are located at the same
addresses as the corresponding TODA and TODB registers. Access to the
ALARM is governed by bit 7 in the Control Registers CRB and CRD. The
ALARM registers are write-only; any read of a TOD address will read
time regardless of the state of the ALARM access control bits.
A specific sequence of events must be followed for proper
setting and reading of each TOD. A TOD is automatically stopped
whenever a write to the corresponding Hours register occurs. The TOD
will not start again until after a write to the proper 10ths of
seconds register. This assures that a TOD will always start at the
desired time. Since a carry from one stage to the next can occur at
any time with respect to a read operation, a latching function is
included to keep all Time of Day information constant during a read
sequence. All four registers of each TOD latch on a read of the
corresponding Hours register and remain latched until after a read of
the corresponding 10ths of second register. A TOD continues to count
when the output registers are latched. If only one register is to be
read, there is no carry problem and the register can be read "on the
fly", provided that any read of the Hours register if followed by a
read of the proper 10ths of seconds, to disable the latching.
2.3.5.5. Serial Ports (SDRA, SDRB)
Each serial port is a buffered, 8-bit synchronous shift register
system. A control bit (CRA SPA bit, CRC SPB bit) selects input or
output mode for either the SDRA or SDRB port.
In input mode, data on the SPA or SPB pin is shifted into the
corresponding shift register on the rising edge of the signal applied
to the CNTA or CNTB pin, respectively. After 8 CNTA pulses, the data
in the shift register is dumped into the SERIALA Data Register (SDRA)
and an interrupt is generated, SPA bit is set in register ICRA. After
8 CNTB pulses, the data in the shift register is dumped into the
SERIALB Data Register (SDRB) and an interrupt is generated, SPB bit is
set in register ICRB.
In the output mode, TIMER A is used for the baud rate generator
of serial port A, Timer C for serial port B. Data is shifted on an SP
pin at half the underflow rate of the TIMER used. The maximum baud
rate possible is C1MHz divided by four, but the maximum useable baud
rate will be determined by line loading and the speed at which the
receiver responds to input data. Transmission will start following a
write to Serial Data Register (provided the proper TIMER used is
running and in continuous mode). The clock signal derived from TIMER A
would appear as an output on the CNTA pin; the one from TIMER C would
appear on the CNTB pin. The data in the Serial Data Register will be
loaded into its corresponding shift register then shift out to the SPA
or SPB pin when a CNTA or CNTB pulse occurs, respectively.
Data shifted out becomes valid on the falling edge of its CNT
clock and remains valid until the next falling edge. After 8 CNT
pulses, an interrupt is generated to indicate more data can be sent.
If the Serial Data Register was loaded with new information prior to
this interrupt, the new data will automatically be loaded into the
shift register and transmission will continue. If the microprocessor
stays one byte ahead of the shift register, transmission will be
continuous. If no further data is to be transmitted, after the 8th CNT
pulse, CNT will return high and SP will remain at the level of the
last data bit transmitted. SDR data is shifted out MSB first and
serial input data should also appear on this format.
The bidirectional capability of each of the Serial Ports and CNT
clocks allows many 4510 to be connected to a common serial
communication bus on which one Serial Port would act as a master,
sourcing data and shift clock, while the other Serial Port (and all
other ports from other 4510 devices) would act as slaves. All the CNT
and SP outputs are open drain to allow such a common bus. Protocol for
master/slave selection can be transmitted over the serial bus, or via
dedicated handshaking lines.
2.3.5.6. FAST SERIAL MODE
The FAST SERIAL logic consists of a 2-bit write-only register,
which resides in location 0001 (hex). This register may only be
accessed by the CPU if neither the AEC or DMA/ line is low. Upon
reset, both bits in the register are forced low which allows the
device to operate as normal (the CNTA, SPA, PRC57 and FLAGA/ lines
will not be affected).
Bit 1 of the FAST SERIAL register is the Fast Serial Mode
disable bit (DMODE* bit).
Bit 6 of the FAST SERIAL register is the FSDIR* bit. When the
DMODE* bit is set high, the FSDIR* bit will be used as an output to
control the fast serial data direction buffer hardware, and as an
input to sense a fast disk enable signal. This function will affect
the CNTA, SPA, PRC57 and FLAGA/ lines as summarized in the following
table.
DMODE* FSDIR* FUNCTION
0 0 Fast Serial mode is disabled.
x 1 Both the FLAGA/ and the PRC57 lines will behave as
outputs. The FLAGA/ output will reflect the state of
the CNTA pin, whereas the PRC57 output will reflect
the state of the SPA pin.
1 0 Both the CNTA and SPA lines will behave as outputs.
The CNTA output will reflect the state of the FLAGA/
pin, whereas the SPA output will reflect that of the
PRC57 pin.
2.3.5.7. Interrupt Control Registers (ICRA, ICRB)
These registers control the following sources of interrupts:
i. Underflows from TIMER A, TIMER B, TIMER C and TIMER D.
ii. TODA ALARM and TODB ALARM.
iii. SERIALA and SERIALB Port full/empty conditions.
iv. FLAGA/ and FLAGB/ low transitions.
The ICRA and ICRB registers each provides masking and interrupt
information. ICRA and ICRB each consists of a write-only MASK register
and a read-only-DATA register. Any interrupt will set the
corresponding bit in the DATA register. Any interrupt which is enabled
by the MASK register will set the IR bit (MSB) of its corresponding
DATA register and bring the IRQ/ pin low. In a multi-chip system, the
IR bit (IRA of ICRA or IRB of ICRB) can be polled to detect which chip
has generated an interrupt request. The interrupt DATA register is
cleared and the IRQ/ line returns high following a read of the DATA
register. Since each interrupt sets and interrupt bit regardless of
the MASK, and each interrupt bit can be selectively masked to
prevent the generation of a processor interrupt, it is possible to
intermix polled interrupts with true interrupts. However, polling
either of the IR bits will cause its corresponding DATA register to
clear, therefore, it is up to the user to preserve the information
contained in the DATA registers if any polled interrupts were present.
Both MASK (ICRA, ICRB) registers provide convenient control of
individual mask bits. When writing to a MASK register, if bit 7 of the
data written (corresponding to AS/C in ICRA, or BS/C in ICRB) is a
ZERO, any mask bit written with a one will be cleared, while those
bits written with a zero will be unaffected. In order for an interrupt
flag to set the IR bit and generate an Interrupt Request, the
corresponding MASK bit must be set in the corresponding MASK Register.
2.3.5.8. Control Registers (CRA, CRB, CRC, CRD)
CRA (0XE):
BIT Bit Name Function
0 STARTA 1=START TIMER A, 0=STOP TIMER A. This bit is
automatically reset when TIMER A underflow occurs
during one-shot mode.
1 PRB6 ON 1=TIMER A output appears on PRB6, 0=PRB6 normal port
operation.
2 OUT-A MODE 1=TOGGLE output applied on port PRB6,
0=PULSE output applied on port PRB6.
3 RUN-A MODE 1=ONE-SHOT TIMER A operation,
0=CONTINUOUS TIMER A operation.
4 LOADA 1=FORCE LOAD on TIMER A (this is a STROBE input,
there is no data storage, bit 4 will always read
back a zero and writing a zero has no effect).
5 TMRA INMODE 1=TIMER A counts positive CNTA transitions,
0=TIMER A counts internal C1MHZ pulses.
6 SPA MODE 1=SERIAL A PORT output mode (CNTA sources shift
clock),
0=SERIAL A PORT input mode (external shift clock
on CNTA).
7 TODA IN 1=50 Hz operation. C7MHZ divided down by 101339 to
generate TODA input of 10 Hz.
0=60 Hz operation. C7MHZ divided down by 102273 to
generate TODA input of 10 Hz.
CRB (0XF):
BIT Bit Name Function
(Bits 0-4 of the CRB register operate identically to bits 0-4 of the
CR7 register, except that functions now apply to TIMER B and bit 1
control the output of TIMER B on PRB7).
5,6 TIMERB Bits 5 and 6 select one of four input modes for
INMODE TIMER B as follows:
CRB6 CRB5
0 0 TIMER B counts C1MHz pulses.
0 1 TIMER B counts positive CNTA transitions.
1 0 TIMER B counts TIMERA underflow pulses.
1 1 TIMER B counts TIMERA underflows while
CNTA is high.
7 ALARM TODA 1=writing to TODA registers sets ALARM,
0=writing to TODA registers sets TODA clock.
CRC (1XE):
BIT Bit Name Function
0 STARTC 1=START TIMER C, 0=STOP TIMER C. This bit is
automatically reset when TIMER C underflow occurs
during one-shot mode.
1 PRD6 ON 1=TIMER C output appears on PRD6, 0=PRD6 normal port
operation.
2 OUT-C MODE 1=TOGGLE output applied on port PRD6,
0=PULSE output applied on port PRD6.
3 RUN-C MODE 1=ONE-SHOT TIMER C operation,
0=CONTINUOUS TIMER C operation.
4 LOADC 1=FORCE LOAD on TIMER C (this is a STROBE input,
there is no data storage, bit 4 will always read
back a zero and writing a zero has no effect).
5 TMRC INMODE 1=TIMER C counts positive CNTB transitions,
0=TIMER C counts internal C1MHZ pulses.
6 SPB MODE 1=SERIAL B PORT output mode (CNTB sources shift
clock),
0=SERIAL B PORT input mode (external shift clock
on CNTB).
7 TODB IN 1=50 Hz operation. C7MHZ divided down by 101339 to
generate TODB input of 10 Hz.
0=60 Hz operation. C7MHZ divided down by 102273 to
generate TODB input of 10 Hz.
CRD (1XF):
BIT Bit Name Function
(Bits 0-4 of the CRD register operate identically to bits 0-4 of the
CRD register, except that functions now apply to TIMER D and bit 1
controls the output of TIMER D on PRD7).
5,6 TIMERD Bits 5 and 6 select one of four input modes for
INMODE TIMER D as follows:
CRD6 CRD5
0 0 TIMER D counts C1MHz pulses.
0 1 TIMER D counts positive CNTB transitions.
1 0 TIMER D counts TIMERC underflow pulses.
1 1 TIMER D counts TIMERC underflows while
CNTB is high.
7 ALARM TODB 1=writing to TODB registers sets ALARM,
0=writing to TODB registers sets TODA clock.
C65 Peripheral Control Utilization
6526 cia complex interface adapter #1
keyboard / joystick / paddles / mouse / lightpen / fast serial
pra0 keybd output c0 / joystick #1 up / mouse right button
pra1 keybd output c1 / joystick #1 down
pra2 keybd output c2 / joystick #1 left / paddle "A" fire button
pra3 keybd output c3 / joystick #1 right / paddle "B" fire button
pra4 keybd output c4 / joystick #1 fire / mouse left button
pra5 keybd output c5 /
pra6 keybd output c6 / / select port #1 paddles|mouse
pra7 keybd output c7 / / select port #2 paddles|mouse
prb0 keybd input r0 / joystick #2 up / mouse right button
prb1 keybd input r1 / joystick #2 down / paddle "A" fire button
prb2 keybd input r2 / joystick #2 left / paddle "B" fire button
prb3 keybd input r3 / joystick #2 right
prb4 keybd input r4 / joystick #2 fire / mouse left button
prb5 keybd input r5 /
prb6 keybd input r6 / timer b: toggle/pulse output
prb7 keybd input r7 / timer a: toggle/pulse output
timer 1 & cra : fast serial
timer 2 & crb :
tod :
sdr :
icr :
6526 cia complex interface adapter #2
user port / rs232 / serial bus / VCC bank / NMI
pra0 va14 VIC 16K bank select
pra1 va15
pra2 rs232 DATA output (C64 mode only)
pra3 serial ATN output
pra4 serial CLK output
pra5 serial DATA output
pra6 serial CLK input
pra7 serial DATA input
prb0 user port / rs232 received data (C64 mode only)
prb1 user port / rs232 request to send
prb2 user port / rs232 data terminal ready
prb3 user port / rs232 ring indicator
prb4 user port / rs232 carrier detect
prb5 user port
prb6 user port / rs232 clear to send
prb7 user port / rs232 data set ready
timer 1 & cra : rs232 baud rate (C64 mode only)
timer 2 & crb : rs232 bit check (C64 mode only)
tod :
sdr :
icr : nmi (/irq)
2.3.6. UART Operation
The device contains seven registers to control the different UART
modes of operation. Section 2.2 describes how to access these
registers.
The UART modes can be programmed by accessing the UART control
register, URCR, whose bits function as described below.
2.3.6.1. UART Control Register (DRCR)
BIT Bit Name Function
0 PARITY EVEN 1 = Even Parity. If parity is enabled, the
transmitter will assert the parity bit (P) to a low
when "even" parity data is transmitted, otherwise
it will pull it high. The receiver checks that the
parity bit is asserted, or low, if the data
received has even parity; if the bit is not
asserted, the device will indicate a parity error.
0=Odd Parity. If parity is enabled, the transmitter
will pull the parity bit (P) low when "odd" parity
data is transmitted, otherwise it will pull it
high. The receiver checks that the parity bit is
asserted if the data received has odd parity; if
the bit is not asserted when data had odd parity,
the device will indicate a parity error.
1 PARITY EN 1 = Parity Enabled.
0 = Parity Disabled. The transmitter and receiver
will not allocate a parity bit in the data, instead
a stop bit will be used in its place. See the Data
Configuration chart below.
2,3 CHAR LENGTH These two bits are used to select the number of
bits per character to be transmitted or received.
5, 6, 7 or 8 bits per character may be selected as
follows:
CH1 CH0
--- ---
0 0 eight bits per character
0 1 seven bits per character
1 0 six bits per character
1 1 five bits per character
4,5 UART MODE These two bits select whether operations will be
asynchronous or synchronous for the transmitter
and/or receiver. The actual selection is done as
follows:
DM1 DM0
--- ---
0 0 both transmitter and receiver operate
in asynchronous mode.
0 1 receiver operates in synchronous mode,
transmitter in asynchronous mode.
1 x receiver operates in asynchronous mode,
transmitter in synchronous mode.
6 RCVR EN 0 = Receiver is disabled.
1 = Receiver is Enabled. To provide noise immunity,
the duration of a bit interval is segmented into
16 subintervals. This is also used to verify that
a high to low transition (START bit) on the RXD
line is valid (stays low) at the half point of a
bit duration; if not valid, operation will not
start.
If after an idle period, a high to low transition
is detected on the RXD line and is verified to be
low, the receiver will synchronized itself to the
incoming character for the duration of the
character. Received data is then sampled or latched
in the center of a bit time to determine the value
of the remaining bits. The LSB of the data is the
leading bit received. Any unused high order
register bits will be set "high". The receiver
expects the data to have only one parity bit (when
parity is enabled) and one stop bit. At the end of
the character reception, the receiver will check
whether any errors have occured and will update the
status register (URSR) accordingly. In addition, if
no errors were encountered the receiver will load
the contents of the shift register into the
Receiver Data Register, eliminating parity and stop
bits.
In synchronous mode, the receiver will reconfigure
its Data Register and Shift Register so that only 8
data bits are always accepted on the RXD line. This
mode only works if an external clock is applied on
the PRC2 input line, which is used to shift the
bits into the Receiver Shift register. Data on the
RXD is latched at the rising edge of the external
clock applied in PRC2.
7 XMITR EN 0 = Transmitter is disabled.
1 = Transmitter is Enabled. Transmitter will start
operation once the microprocessor writes data to
the transmitter data register (DREG), after which
the Transmitter Shift Register is loaded and the
start bit is placed on the TXD line. The LSB of the
data is the leading bit being transmitted. The
Transmitter is "doubled buffered" which means that
the CPU can load a new character as soon as the
previous one starts transmission. This is indicated
by the status register, bit 6 (URSR6 -- Empty Data
Register), which when set, it indicates that the
data register is ready to accept the next
character. The character data format is illustrated
by figure 1.3. In synchronous mode, the transmitter
will reconfigure its Data Register and Shift
Register so that only 8 data bits are always
transmitted on the TXD line, eliminating all parity
and stop bits. The external clock output will be
placed in the PRC2 line and will shift the data out
of the transmitter shift register. Data on the TXD
line will change on the falling edge of the PRC2
signal, the external clock.
2.3.6.2. UART Status Register (URSR)
BIT Bit Name Function
0 FULL Receiver Data Register Full bit. This bit is forced
to a low upon reset, or after the data register
(DREG) is read. This bit is enabled only if the
RCVER EN bit is set in the URCR register. The FULL
bit is set when the character being received is
transferred from the receiver shift register into
the receiver data register. If an error is
encountered in the character data, this bit will
not be set and the proper error bit will be set in
the URSR register.
1 OVR Receiver Over-Run Error bit. This bit is cleared
upon reset or after reading the receiver data
register. This bit is set if the new received
charater is attempted to be transferred from the
receiver shift register before reading the last
character from the data register. Therefore, the
last character is preserved in the data register
while the new received character is lost.
2 PRTY Receiver Parity Error bit. This bit is cleared upon
reset or after reading the receiver data register.
The PRTY bit will be set when a parity error is
detected on the received character, provided the
PARITY EN bit is set and receiver is running
asynchronously.
3 FRME Receiver Frame Error bit. This bit is cleared upon
reset or after reading the receiver data register.
The FRME bit is set whenever the received character
contains a low in the first stop-bit slot.
4 IDLE Receiver Idle bit. When this bit is written to a
"high", the status register bits 0-3 are disabled
until the receiver detects 10 consecutive marks,
highs, on the RXD line, at which time the IDLE bit
is cleared. This bit is also cleared upon reset.
This bit allows the microprocessor, or any external
microprocessor device, to ignore the transmission
of a character until the start of the next
character.
5 ENDT Transmitter End of Transmission bit. This bit is
cleared upon reset or whenever data is written into
the transmitter data register, DREG. Setting this
bit would disable the Transmitter Empty bit, EMPTY,
until device completes transmission.
2.3.6.3. Character Configuration
ASYNC MODE
S
T B P = PARITY BIT
A I STP = STOP BIT
R T
T LSB --+
MARK>-+ +---+---+---+---+---+---+---+---+ | P
| | D0| D1| D2| D3| D4| P |STP|STP| <-- 5-BIT/CHARACTER | A
+---+---+---+---+---+---+---+---+---+ | R
| I
--+ +---+---+---+---+---+---+---+---+---+ | T
| | D0| D1| D2| D3| D4| D5| P |STP|STP| <-- 6-BIT/CHARACTER | Y
+---+---+---+---+---+---+---+---+---+---+ |
+-> E
--+ +---+---+---+---+---+---+---+---+---+---+ | N
| | D0| D1| D2| D3| D4| D5| D6| P |STP|STP| <-- 7-BIT/CHARACTER | A
+---+---+---+---+---+---+---+---+---+---+---+ | B
| L
--+ +---+---+---+---+---+---+---+---+---+---+ | E
| | D0| D1| D2| D3| D4| D5| D6| D7| P |STP| <-- 8-BIT/CHARACTER | D
+---+---+---+---+---+---+---+---+---+---+---+ |
--+
--+
--+ +---+---+---+---+---+---+---+ | P
| | D0| D1| D2| D3| D4|STP|STP| <-- 5-BIT/CHARACTER | A
+---+---+---+---+---+---+---+---+ | R
| I
--+ +---+---+---+---+---+---+---+---+ | T
| | D0| D1| D2| D3| D4| D5|STP|STP| <-- 6-BIT/CHARACTER | Y
+---+---+---+---+---+---+---+---+---+ |
+-> D
--+ +---+---+---+---+---+---+---+---+---+ | I
| | D0| D1| D2| D3| D4| D5| D6|STP|STP| <-- 7-BIT/CHARACTER | S
+---+---+---+---+---+---+---+---+---+---+ | A
| B
--+ +---+---+---+---+---+---+---+---+---+---+ | L
| | D0| D1| D2| D3| D4| D5| D6| D7|STP|STP| <-- 8-BIT/CHARACTER | E
+---+---+---+---+---+---+---+---+---+---+---+ | D
--+
CHARACTER CONFIGURATION
TABLE 3
2.3.6.4. Register Map
C65 UART
R/W REG NAME D7 D6 D5 D4 D3 D2 D1 D0
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | | | | | | | | |
| R/W | 0 | DATA | R/X7 | R/X6 | R/X5 | R/X4 | R/X3 | R/X2 | R/X1 | R/X0 |
| | | | | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | | | | | | | | |
| READ| 1 | STATUS | XMIT | XMIT | ENDT | IDLE | FRAME|PARITY| OVER | RCVR |
| | | | DONE | EMPTY| (R/W)| (R/W)| | | RUN | FULL |
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | | | | | |
| R/W | 2 | CONTROL | XMIT | RCVR | UART MODE | WORD LENGTH | PARITY |
| | | | ON | ON | | | ON EVEN |
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | | | | | | | | |
| R/W | 3 | BAUD LO | BRL7 | BRL6 | BRL5 | BRL4 | BRL3 | BRL2 | BRL1 | BRL0 |
| | | | | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | | | | | | | | |
| R/W | 4 | BAUD HI | BRH7 | BRH6 | BRH5 | BRH4 | BRH3 | BRH2 | BRH1 | BRH0 |
| | | | | | | | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | | | | | | | | |
| R/W | 5 | INT MASK | XMIT | RCVR | XMIT | RCVR | -- | -- | -- | -- |
| | | | IRQ | IRQ | NMI | NMI | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
| | | | | | | | | | | |
| READ| 6 | INT FLAG | XMIT | RCVR | XMIT | RCVR | -- | -- | -- | -- |
| | | | IRQ | IRQ | NMI | NMI | | | | |
+-----+---+----------+------+------+------+------+------+------+------+------+
The BAUD RATE can be generated using the following formulas:
URCLK URCLK
BaudRate = ---------------- or, COUNT = --------------- - 1
16 x (COUNT+1) 16 x BaudRate
Where: COUNT = value loaded into BAUD RATE register
URCLK = C7Mhz input, 7.15909 MHz NTSC
7.09375 MHz PAL
The following tables show some of the most common data rates. Data
rate errors of less than +/-1.5% are acceptable for most purposes.
A. NTSC URCLK = 7.15909 MHZ
+----+-----------+---------+-----------+---------+
| BR | BAUD RATE | COUNT | BAUD RATE | PERCENT |
| # | REQUIRED | (HEX) | OBTAINED | ERROR |
+----+-----------+---------+-----------+---------+
| 1 | 50 | 22F4 | 49.999 | .0015 |
| 2 | 75 | 174D | 74.999 | .0015 |
| 3 | 110 | 0FE3 | 109.991 | .0080 |
| 4 | 134.5 | 0CFE | 134.488 | .0090 |
| 5 | 150 | 0BA6 | 149.998 | .0015 |
| 6 | 300 | 05D2 | 299.895 | .035 |
| 7 | 600 | 02E9 | 599.79 | .035 |
| 8 | 1200 | 0174 | 1199.58 | .035 |
| 9 | 1800 | 00F8 | 1796.96 | .17 |
| 10 | 2400 | 00B9 | 2392.74 | .30 |
| 11 | 3600 | 007B | 3608.41 | .23 |
| 12 | 4800 | 005C | 4811.22 | .23 |
| 13 | 7200 | 003D | 7216.82 | .23 |
| 14 | 9600 | 002E | 9520.07 | .83 |
| 15 | 19200 | 0016 | 19454.0 | 1.323 |
| 16 | 31250 | 000D | 31960.2 | 1.023 | (MIDI)
| 0 | 56000 | 0007 | 55930.4 | .124 |
+----+-----------+---------+-----------+---------+
B. PAL URCLK = 7.09375 MHZ
+----+-----------+---------+-----------+---------+
| BR | BAUD RATE | COUNT | BAUD RATE | PERCENT |
| # | REQUIRED | (HEX) | OBTAINED | ERROR |
+----+-----------+---------+-----------+---------+
| 1 | 50 | 22A2 | 50.001 | .0020 |
| 2 | 75 | 1716 | 75.005 | .0080 |
| 3 | 110 | 0FBE | 109.987 | .010 |
| 4 | 134.5 | 0CDF | 134.514 | .010 |
| 5 | 150 | 0B8B | 149.986 | .009 |
| 6 | 300 | 05C5 | 299.973 | .009 |
| 7 | 600 | 02E2 | 599.75 | .009 |
| 8 | 1200 | 0170 | 1198.27 | .144 |
| 9 | 1800 | 00F5 | 1802.27 | .126 |
| 10 | 2400 | 00B8 | 2396.54 | .144 |
| 11 | 3600 | 007A | 3604.55 | .126 |
| 12 | 4800 | 005B | 4819.12 | .398 |
| 13 | 7200 | 003D | 7150.96 | .68 |
| 14 | 9600 | 002D | 9638.25 | .40 |
| 15 | 19200 | 0016 | 19276.5 | .40 |
| 16 | 31250 | 000D | 31668.5 | 1.01 | (MIDI)
| 0 | 56000 | 0007 | 55419.9 | 1.04 |
+----+-----------+---------+-----------+---------+
2.3.7. CPU
2.3.7.1. Introduction
The 4502, upon reset, looks and acts like any other CMOS 6502
processor, with the exception that many instructions are shorter or
require less cycles than they used to. This causes programs to execute
in less time that older versions, even at the same clock frequency.
The, stack pointer has been expanded to 16 bits, but can be used
in two different modes. It can be used as a full 16-bit (word) stack
pointer, or as an 8-bit (byte) pointer whose stack page is
programmable. On reset, the byte mode is selected with page 1 set as
the stack page. This is done to make it fully 65C02 compatible.
The zero page is also programmable via a new register, the "B" or
"Base Page" register. On reset, this register is cleared, thus giving
a true "zero" page for compatability reasons, but the user can define
any page in memory as the "zero" page.
A third index register, "Z", has been added to increase
flexibility in data manipulation. This register is also cleared, on
reset, so that the STZ instructions still do what they used to, for
compatibility.
This is a list of opcodes that have been added to the 210
previously defined MOS, Rockwell, and GTE opcodes.
***KEN*** I think the GTE extensions are the 27 new opcodes that appeared
***KEN*** in the W65C02. The Rockwell extensions are the 32 new opcodes
***KEN*** to support BBR/BBS/RMB/SMB instructions. This chip has no support
***KEN*** for any of the new opcodes from the W65C802/W65C816. The original
***KEN*** NMOS 6502 had 151 defined opcodes. 151 + 27 + 32 = "210 previously
***KEN*** defined opcodes."
1. Branches and Jumps
* after the opcode denotes a new command
+ after the opcode denotes expanded functionality
93* BCC label word-relative
B3* BCS label word-relative
F3* BEQ label word-relative
33* BMI label word-relative
D3* BNE label word-relative
13* BPL label word-relative
83* BRA label word-relative
53* BVC label word-relative
73* BVS label word-relative
63* BSR label Branch to subroutine (word relative)
22* JSR (ABS) Jump to subroutine absolute indirect
23* JSR (ABS,X) Jump to subroutine absolute indirect, X
62* RTN # Return from subroutine and adjust stack pointer
2. Arithmetic Operations
42* NEG A Negate (or 2's complement) accumulator
43* ASR A Arithmetic Shift right accumulator or memory
44* ASR ZP
54* ASR ZP,X
E3* INW ZP Increment Word
C3* DEW ZP Decrement Word
1B* INZ Increment and
3B* DEZ Decrement Z register
CB* ASW ABS Arithmetic Shift Left Word
EB* ROW ABS Rotate Left Word
12+ ORA (ZP),Z These were formerly (ZP) non-indexed
32+ AND (ZP),Z now are indexed by Z register
52+ EOR (ZP),Z (when .Z=0, operation is the same)
72+ ADC (ZP),Z
D2+ CMP (ZP),Z
F2+ SBC (ZP),Z
C2* CPZ IMM Compare Z register with memory immediate,
D4* CP2 ZP zero page, and
DC* CPZ ABS absolute.
3. Loads, Stores, Pushes, Pulls and Transfers
B2+ LDA (ZP),Z formerly (ZP)
A3* LDZ IMM Load Z register immediate,
AB* LDZ ABS absolute,
BB* LDZ ABS,X absolute,X.
E2* LDA (d,SP),Y Load Accu via stack vector indexed by Y
82* STA (d,SP),Y and Store
9B* STX ABS,Y Store X Absolute,Y
8B* STY ABS,X Store Y Absolute,X
64+ STZ ZP Store Z register (formerly store zero)
9C+ STZ ABS
74+ STZ ZP,X
9E+ STZ ABS,X
92+ STA (ZP),Z formerly (ZP)
F4* PHW IMM Push Data Immediate (word)
FC* PHW ABS Push Data Absolute (word)
DB* PHZ Push Z register onto stack
FB* PLZ Pull Z register from stack
4B* TAZ Transfer Accumulator to Z register
6B* TZA Transfer Z register to Accumulator
5B* TAB Transfer Accumulator to Base page register
7B* TBA Transfer Base page register to Accumulator
0B* TSY Transfer Stack Pointer High byte to Y register
2B* TYS Transfer Y register to Stack Pointer High byte
02* CLE Clear the Extend Disable bit in the P register.
In other words, set the stack pointer to 16 bit
mode.
03* SEE Set the Extend Disable bit in the P register.
In other words, set the staack pointer to 8 bit
mode.
5C* MAP Enter MAP mode, and start setting up a memory
mapping.
EA+ EOM Exit MAP mode, formerly NOP.
2.3.7.2. CPU Operation
The 4502 has the following 8 user registers:
A accumulator
X index-X
Y index-Y
Z index-Z
B Base-page
P Processor status
SP Stack pointer
PC Program counter
Accumulator
The accumulator is the only general purpose computational
register. It can be used for arithmetic functions add, subtract,
shift, rotate, negate, and for Boolean functions and, or,
exclusive-or, and bit operations. It cannot, however, be used as an
index register.
Index X
The index register X has the largest number of opcodes pertaining
to, or using it. It can be incremented, decremented, or compared, but
not used for arithmetic or logical (Boolean) operations. It differs
from other index registers in that it is the only register that can be
used in indexed-indirect or (bp,X) operations. It cannot be used in
indirect-indexed or (bp),Y mode.
Index Y
The index register Y has the same computational constraints as
the X register, but finds itself in a lot less of the opcodes, making
it less generally used. But the index Y has one advantage over index
X, in that it can be used in indirect-indexed operations or (bp),Y
mode.
Index Z
The index register Z is the most unique, in that it is used in
the smallest number of opcodes. It also has the same computation
limitations as the X and Y registers, but has an extra feature. Upon
reset, the Z register is cleared so that the STZ (store zero) opcodes
and non-indexed indirect opcodes from previous 65C02 designs are
emulated. The Z register can also be used in indirect-indexed or
(bp),Z operations.
Base page B register
Early versions of 6502 microprocessors had a special subset of
instructions that required less code and less time to execute. These
were referred to as the "zero page" instructions. Since the addressing
page was always known, and known to be zero, addresses could be
specified as a single byte, instead of two bytes.
The CSG4502 also implements this same "zero page" set of
instructions, but goes one step further by allowing the programmer to
specify which page is to be the "zero page". Now that the programmer
can program this page, it is now, not necessarily page zero, but
instead, the "selected page". The term "base page" is used, however.
The B register selects which page will be the "base page", and
the user sets it by transferring the contents of the accumulator to
it. At reset, the B register is cleared, giving initially a true "zero
page".
Processor status P register
The processor status register is an 8-bit register which is used
to indicate the status of the microprocessor. It contains 8 processor
"flags". Some of the flags are set or reset based on the results of
various types of operations. Others are more specific. The flags
are...
Flag Name Typical indication
N Negative result of operation is negative
V Overflow result of add or subtract causes signed overflow
E Extend disables stack pointer extension
B Break interrupt was caused by BRK opcode
D Decimal perform add/subtract using BCD math
I Interrupt disable IRQ interrupts
Z Zero result of Operation is zero
C Carry operation caused a carry
Stack Pointer SP
The stack pointer is a 16 bit register that has two modes. It can
be programmed to be either an 8-bit page programmable pointer, or a
full 16-bit pointer. The processor status E bit selects which mode
will be used. When set, the E bit selects the 8-bit mode. When reset,
the E bit selects the 16-bit mode.
Upon reset, the CSG 4502 will come up in the 8-bit page-
programmable mode, with the stack page set to 1. This makes it
compatible with earlier 6502 products. The programmer can quickly
change the default stack page by loading the Y register with the
desired page and transferring its contents to the stack pointer high
byte, using the TYS opcode. The 8-bit stack pointer can be set by
loading the X register with the desired value, and transferring its
contents to the stack pointer low byte, using the TXS opcode.
To select the 16-bit stack pointer mode, the user must execute a
CLE (for CLear Extend disable) opcode. Setting the 16-bit pointer is
done by loading the X and Y registers with the desired stack pointer
low and high bytes, respectively, and then transferring their contents
to the stack pointer using TXS and TYS. To return to 8-bit page mode,
simple execute a SEE (SEt Extend disable) opcode.
*************************************************************
* WARNING *
* *
* If you are using Non-Maskable-Interrupts, or Interrupt *
* Request is enabled, and you want to change BOTH stack *
* pointer bytes, do not put any code between the TXS and *
* TYS opcodes. Taking this precaution will prevent any *
* interrupts from occuring between the setting of the two *
* stack pointer bytes, causing a potential for writing *
* stack data to an unwanted area. *
*************************************************************
Program Counter PC
The program counter is a 16-bit up-only counter that determines
what area of memory that program information will be fetched from. The
user generally only modifies it using jumps, branches, subroutine
calls, or returns. It is set initially, and by interrupts, from
vectors at memory addresses FFFA through FFFF (hex). See "Interrupts"
below.
2.3.7.3. 65CE02 Interrupts
There are four basic interrupt sources on the CSG 4502. These are
RES*, IRQ*, NMI*, and SO, for Reset, Interrupt Request, Non-Maskable
Interrupt, and Set Overflow. The Reset is a hard non-recoverable
interrupt that stops everything. The IRQ is a "maskable" interrupt, in
that its occurance can be prevented. The MMI is "non-maskable", and if
such an event occurs, cannot be prevented. The SO, or Set Overflow, is
not really an interrupt, but causes an externally generated condition,
which can be used for control of program flow.
One important design feature, which must be remembered is that no
interrupt can occur immediately after a one-cycle opcode. This is very
important, because there are times when you want to temporarily
prevent interrupts from occurring. The best example of this is, when
setting a 16-bit stack pointer, you do not want an interrupt to occur
between the times you set the low-order byte, and the high-order byte.
If it could happen, the interrupt would do stack writes using a
pointer that was only partially set, thus, writing to an unwanted
area.
IRQ*
The IRQ* (Interrupt ReQuest) input will cause an interrupt, if it
is at a low logic level, and the I processor status flag is reset. The
interrupt sequence will begin with the first SYNC after a
multiple-cycle opcode. The two program counter bytes PCH and PCL, and
the processor status register P, are pushed onto the stack. (This
causes the stack pointer SP to be decremented by 3.) Then the program
counter bytes PCL and PCH are loaded from memory addresses FFFE and
FFFF, respectively.
An interrupt caused by the IRQ* input, is similar to the BRK
opcode, but differs, as follows. The program counter value stored on
the stack points to the opcode that would have been executed, had the
interrupt not occurred. On return from interrupt, the processor will
return to that opcode. Also, when the P register is pushed onto the
stack, the B or "break" flag pushed, is zero, to indicate that the
interrupt was not software generated.
NMI*
The NMI* (Non-Maskable Interrupt) input will cause an interrupt
after receiving high to low transition. The interrupt sequence will
begin with the first SYNC after a multiple-cycle opcode. NMI* inputs
cannot be masked by the processor status register I flag. The two
program counter bytes PCH and PCL, and the processor status register
P, are pushed onto the stack. (This causes the stack pointer SP to be
decremented by 3.) Then the program counter bytes PCL and PCH are
loaded from memory addresses FFFA and FFFB.
As with IRQ*, when the P register is pushed onto the stack, the B
or "break" flag pushed, is zero, to indicate that the interrupt was
not software generated.
RES*
The RES* (RESet) input will cause a hard reset instantly as it is
brought to a low logic level. This effects the following conditions.
The currently executing opcode will be terminated. The B and Z
registers will be cleared. The stack pointer will be set to "byte"
mode/with the stack page set to page 1. The processor status bits E
and I will be set.
The RES* input should be held low for at least 2 clock cycles.
But once brought high, the reset sequence begins on the CPU cycle. The
first four cycles of the reset sequence do nothing. Then the program
counter bytes PCL and PCH are loaded from memory addresses FFFC and
FFFD, and normal program execution begins.
SO
The SO (Set Overflow) input does, as its name implies, set the
overflow or V processor status flag. The effect is immediate as this
active low signal is brought or held at a low logic level. Care should
be taken if this signal is used, as some of the opcodes can set or
reset the overflow flag, as well. NOTE: The SO pin has been removed
for C65.
2.3.7.4. 65CE02 Addressing Modes
It should be noted that all 8-bit addresses are referred to as
"byte" addresses, and all 16-bit addresses are referred to as "word"
addresses. In all word addresses, the low-order byte of the address is
fetched from the lower of two consecutive memory addresses, and the
high-order byte of the address is fetched the higher of the two. So,
in all operations, the low-order address is fetched first.
Implied OPR
The register or flag affected is identified entirely by the
opcode in this (usually) single cycle instruction. In this document,
any implied operation, where the implied register is not explicitly
declared, implies the accumulator. Example: INC with no arguments
implies "increment the accumulator".
Immediate (byte, word) OPR #xx
The data used in the operation is taken from the byte or bytes
immediately following the opcode in the 2-byte or 3-byte instruction.
Base Page OPR bp (formerly Zero Page)
The second byte of the two-byte instruction contains the
low-order address byte, and the B register contains the high-order
address byte of the memory location to be used by the operation.
Base Page, indexed by X OPR bp,X (formerly Zero Page,X)
The second byte of the two-byte instruction is added to the X
index register to form the low-order address byte, and the B register
contains the high-order address byte of the memory location to be used
by the operation.
Base Page, indexed by Y OPR bp,Y (formerly Zero Page,Y)
The second byte of the two-byte instruction is added to the Y
index register to form the low-order address byte, and the B register
contains the high-order address byte of the memory location to be used
by the operation.
Absolute OPR abs
The second and third bytes of the three-byte instruction contain
the low-order and high-order address bytes, respectively, of the
memory location to be used by the operation.
Absolute, indexed by X OPR abs,X
The second and third bytes of the three-byte instruction are
added to the unsigned contents of the X index register to form the
low-order and high-order address bytes, respectively, of the memory
location to be used by the operation.
Absolute, indexed by Y OPR abs,Y
The second and third bytes of the three-byte instruction are
added to the unsigned contents of the Y index register to form the
low-order and high-order address bytes, respectively, of the memory
location to be used by the operation.
Indirect (word) OPR (abs) (JMP and JSR only)
The second and third bytes of the three-byte instruction contain
the low-order and high-order address bytes, respectively, of two
memory locations containing the low-order and high-order JMP or JSR
addresses, respectively.
Indexed by X, indirect (byte) OPR (bp,X) (formerly (zp,X) )
The second byte of the two-byte instruction is added to the
contents of the X register to form the low-order address byte, and the
contents of the B register contains the high-order address byte, of
two memory locations that contain the low-order and high-order address
of the memory location to be used by the operation.
Indexed by X, indirect (word) OPR (abs,X) (JMP and JSR only)
The second and third bytes of the three-byte instruction are
added to the unsigned contents of the X index register to form the
low-order and high-order address bytes, respectively, of two memory
locations containing the low-order and high-order JMP or JSR address
bytes.
Indirect, indexed by Y OPR (bp),Y (formerly (zp),Y )
The second byte of the two-byte instruction contains the
low-order byte, and the B register contains the high-order address
byte of two memory locations whose contents are added to the unsigned
Y index register to form the address of the memory location to be used
by the operation.
Indirect, indexed by Z OPR (bp),Z (formerly (zp) )
The second byte of the two-byte instruction contains the
low-order byte, and the B register contains the high-order address
byte of two memory locations whose contents are added to the unsigned
Z index register to form the address of the memory location to be used
by the operation.
Stack Pointer Indirect, indexed by Y OPR (d,SP),Y (new)
The second byte of the two-byte instruction contains an unsigned
offset value, d, which is added to the stack pointer (word) to form
the address of two memory locations whose contents are added to the
unsigned Y register to form the address of the memory location to be
used by the operation.
Relative (byte) Bxx LABEL (branches only)
The second byte of the two-byte branch instruction is sign-
extended to a full word and added to the program counter (now
containing the opcode address plus two). If the condition of the
branch is true, the sum is stored back into the program counter.
Relative (word) Bxx LABEL (branches only)
The second and third bytes of the three-byte branch instruction
are added to the low-order and high-order program counter bytes,
respectively. (the program counter now contains the opcode address
plus two). If the condition of the branch is true, the sum is stored
back into the program counter.
2.3.7.5. 65CE02 Instruction Set
Add memory to accumulator with carry ADC
A=A+M+C
Addressing Mode Abbrev. Opcode
immediate IMM 69
base page BP 65
base page indexed X BP,X 75
absolute ABS 6D
absolute indexed X ABS,X 7D
absolute indexed Y ABS,Y 79
base page indexed indirect X (BP,X) 61
base page indirect indexed Y (BP),Y 71
base page indirect indexed Z (BP),Z 72
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
The ADC instructions add data fetched from memory and carry to
the contents of the accumulator. The results of the add are then
stored in the accumulator. If the "D" or Decimal Mode flag, in the
processor status register, then a Binary Coded Decimal (BCD) add is
performed.
The "N" or Negative flag will be set if the sum is negative,
otherwise it is cleared. The "V" or Overflow flag will be set if the
sign of the sum is different from the sign of both addends, indicating
a signed overflow. Otherwise, it is cleared. The "Z" or Zero flag is
set if the sum (stored into the accumulator) is zero, otherwise, it is
cleared. The "C" or carry is set if the sum of the unsigned addends
exceeds 255 (binary mode) or 99 (decimal mode).
Flags
N V E B D I Z C
N V - - - - Z C
And memory logically with accumulator AND
A=A.and.M
Addressing Mode Abbrev. Opcode
immediate IMM 29
base page BP 25
base page indexed X BP,X 35
absolute ABS 2D
absolute indexed X ABS,X 3D
absolute indexed Y ABS,Y 39
base page indexed indirect X (BP,X) 21
base page indirect indexed Y (BP),Y 31
base page indirect indexed 2 (BP),Z 32
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
The AND instructions perform a logical "and" between data bits
fetched from memory and the accumulator bits. The results are then
stored in the accumulator. For each accumulator and corresponding
memory bit that are both logical 1's, the result is a 1. Otherwise it
is 0.
The "N" or Negative flag will be set if the bit 7 result is a 1.
Otherwise it is cleared. The "Z" or Zero flag is set if all result
bits are zero, otherwise, it is cleared.
Flags
N V E B D I Z C
N - - - - - Z -
Arithmetic shifts, memory or accumulator, left or right ASL ASR ASW
ASL Arithmetic shift left A or M A<A<<1 or M<M<<1
ASR Arithmetic shift right A or M A<A>>1 or M<M>>1
ASW Arithmetic shift left M (word) Mx<Mw<<1
Opcodes
Addressing Mode Abbrev. ASL ASR ASW
register (A) 0A 43
base page BP 06 44
base page indexed X BP,X 16 54
absolute ABS 0E CB
absolute indexed X ABS,X 1E
Bytes Cycles Mode
1 1 register (ASL)
1 2 register (ASR)
2 4 base page (byte) non-indexed, or indexed X
3 5 absolute non-indexed, or indexed X
3 7 absolute (ASW)
The ASL instructions shift a single byte of data in memory or the
accumulator left (towards the most significant bit) one bit position.
A 0 is shifted into bit 0.
The "N" or Negative bit will be set if the result bit 7 is
(operand bit 6 was) a 1. Otherwise, it is cleared. The "Z" or Zero
flag is set if ALL result bits are zero. The "C" or Carry flag is set
if the bit shifted out is (operand bit 7 was) a 1. Otherwise, it is
cleared.
The ASR instructions shift a single byte of data in memory or the
accumulator right (towards the least significant bit) one bit
position. Since this is an arithmetic shift, the sign of the operand
will be maintained.
The "N" or Negative bit will be set if bit 7 (operand and result)
a 1. Otherwise, it is cleared. The "Z" or Zero flag is set if ALL
result bits are zero. The "C" or Carry flag is set if the bit shifted
out is (operand bit 0 was) a 1. Otherwise, it is cleared.
The ASW instruction shifts a word (two bytes) of data in memory
left (towards the most significant bit) one bit position. A zero is
shifted into bit 0.
The "N" or Negative bit will be set if the result bit 15 is
(operand bit 14 was) a 1. Otherwise, it is cleared. The "Z" or Zero
flag is set if ALL result bits (both bytes) are zero. The "C" or Carry
flag is set if the bit shifted out is (operand bit 15 was) a 1.
Otherwise, it is cleared.
Flags
N V E B D I Z C
N - - - - - Z C
Branch conditional or unconditional BCC BCS BEQ BMI BNE
BPL BRA BVC BVS
Opcode Opcode Byte Opcode Word Opcode
Title Relative Relative Purpose
BCC 90 93 Branch if Carry Clear
BCS B0 B3 Branch if Carry Set
BEQ F0 F3 Branch if EQual (2 flag set)
BMI 30 33 Branch if Minus (N flag set)
BNE D0 D3 Branch if Not Equal (Z flag clear)
BPL 10 13 Branch if PLus (N flag clear)
BRA 80 83 BRanch Always
BVC 50 53 Branch if overflow Clear
BVS 70 73 Branch if overflow Set
Bytes Cycles Mode
2 2 byte-relative
3 3 word-relative
All branches of this type are taken, if the condition indicated
by the opcode is true. All branch relative offsets are referenced to
the branch opcode location+2. This means that for byte-relative, the
offset is relative to the location after the two instruction bytes.
For word-relative, the offset is relative to the last of the three
instruction bytes.
Flags
N V E B D I Z C
- - - - - - - -
Break: (force an interrupt) BRK
Bytes Cycles Mode Opcode
2 7 implied 00 (stack)<PC+1w,P SP<SP-2
The BRK instruction causes the processor to enter the IRQ or
Interrupt ReQuest state. The program counter (now incremented by 2),
bytes PCH and PCL, and the processor status register P, are pushed
onto the stack. (This causes the stack pointer SP to be decremented by
3.) Then the program counter bytes PCL and PCH are loaded from memory
addresses FFFE and FFFF, respectively.
The BRK differs from an externally generated interrupt request
(IRQ) as follows. The program counter value stored on the stack is
PC+2, or the address of the BRK opcode+2. On return from interrupt,
the processor will return to the BRK address+2, thus skipping the
opcode byte, and a following "dummy" byte. A normal IRQ will not add
2, so that a return will execute the interrupted opcode. Also, when
the P register is pushed onto the stack, the B or "break" flag is set,
to indicate that the interrupt was software generated. All outside
interrupts push P with the B flag cleared.
Flags
N V E B D I Z C
- - - - - - - -
Branch to subroutine BSR
Bytes Cycles Mode Opcode
3 5 word-relative 63 (stack)<PC+2w SP<SP-2
The BSR Branch to SubRoutine instruction pushes the two program
counter bytes PCH and PCL onto the stack. It then adds the
word-relative signed offset to the program counter. The relative
offset is referenced to the address of the BSR opcode+2, hence, it is
relative to the third byte of the three-byte BSR instruction. The
return address, on the stack, also points to this address. This was
done to make it compatible with the RTS functionality, and to be
consistant will other word-relative operations.
Flags
N V E B D I Z C
- - - - - - - -
Clear processor status bits CLC CLD CLE CLI CLV
Opcode Cycles Flags
N V E B D I Z C
CLC Clear the Carry bit 18 1 - - - - - - - R
CLD Clear the Decimal mode bit D8 1 - - - - R - - -
CLE Clear stack Extend disable bit 02 2 - - R - - - - -
CLI Clear Interrupt disable bit 58 2 - - - - - R - -
CLV Clear the Oveflow bit B8 1 - R - - - - - -
Bytes Mode
1 implied
All of the P register bit clear instructions are a single byte
long. Most of them require a single CPU cycle. The CLI and CLE require
2 cycles. The purpose of extending the CLI to 2 cycles, is to enable
an interrupt to occur immediately, if one is pending. Interrupts
cannot occur after single cycle instructions.
Compare registers with memory CMP CTX CPY CPZ
CMP Compare accumulator with memory (A-M)
CPX Compare index X with memory (X-M)
CPY Compare index Y with memory (Y-M)
CPZ Compare index Z with memory (Z-M)
Opcodes
Addressing Mode Abbrev. CMP CPX CPY CPZ
immediate IMM C9 E0 C0 C2
base page BP C5 E4 C4 D4
base page indexed X BP,X D5
absolute ABS CD EC CC DC
absolute indexed X ABS,X DD
absolute indexed Y ABS,Y D9
base page indexed indirect X (BP,X) C1
base page indirect indexed Y (BP),Y D1
base page indirect indexed Z (BP),Z D2
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
Compares are performed by subtracting a value in memory from the
register being tested. The results are not stored in any register,
except the following status flags are updated.
The "N" or Negative flag will be set if the result is negative
(assuming signed operands), otherwise it is cleared. The "Z" or Zero
flag is set if the result is zero, otherwise it is cleared. The "C" or
carry flag is set if the unsigned register value is greater than or
equal to the unsigned memory value.
Flags
N V E B D I Z C
N - - - - - Z C
Compare registers with memory CMP CPX CPY CPZ
CMP Compare accumulator with memory (A-M)
CPX Compare index X with memory (X-M)
CPY Compare index Y with memory (Y-M)
CPZ Compare index Z with memory (Z-M)
Opcodes
Addressing Mode Abbrev. CMP CPX CPY CPZ
immediate IMM C9 E0 C0 C2
base page BP C5 E4 C4 D4
base page indexed X BP,X D5
absolute ABS CD EC CC DC
absolute indexed X ABS,X DD
absolute indexed Y ABS,Y D9
base page indexed indirect X (BP.X) C1
base page indirect indexed Y (BP),Y D1
base page indirect indexed Z (BP),Z D2
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
Compares are performed by subtracting a value in memory from the
register being tested. The results are not stored in any register,
except the following status flags are updated.
The "N" or Negative flag will be set if the result is negative
(assuming signed operands), otherwise it is cleared. The "Z" or Zero
flag is set if the result is zero, otherwise it is cleared. The "C" or
carry flag is set if the unsigned register value is greater than or
equal to the unsigned memory value.
Flags
N V E B D I Z C
N - - - - - Z C
Exclusive OR accumulator logically with memory EOR
A=A.or.M.and..not.(A.and.M)
Addressing Mode Abbrev. Opcode
immediate IMM 49
base page BP 45
base page indexed X BP,X 55
absolute ABS 4D
absolute indexed X ABS,X 5D
absolute indexed Y ABS,Y 59
base page indexed indirect X (BP,X) 41
base page indirect indexed Y (BP),Y 51
base page indirect indexed Z (BP),Z 52
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
The EOR instructions perform an "exclusive or" between bits
fetched from memory and the accumulator bits. The results are then
stored in the accumulator. For each accumulator or corresponding
memory bit that are different (one 1, and one 0) the result is a 1.
Otherwise it is 0.
The "N" or Negative flag will be set if the bit 7 result is a 1.
Otherwise it is cleared. The "Z" or Zero flag is set if all result
bits are zero, otherwise, it is cleared.
Flags
N V E B D I Z C
N - - - - - Z -
Jump to subroutine JSR
Addressing Mode Abbrev. Opcode bytes cycles
absolute ABS 20 3 5
absolute indirect (ABS) 22 3 7
absolute indexed indirect X (ABS,X) 23 3 7
The JSR Jump to SubRoutine instruction pushes the two program
counter bytes PCH and PCL onto the stack. It then loads the program
counter with the new address. The return address, stored on the stack,
is actually the address of the JSR opcode+2, or is pointing to the
third byte of the three-byte JSR instruction.
Flags
N V E B D I Z C
- - - - - - - -
Load registers LDA LDX LDY LDZ
LDA Load Accumulator from memory A<M
LDX Load index X from memory X<M
LDY Load index Y from memory Y<M
LDZ Load index Z from memory Z<M
Addressing Mode Abbrev. LDA LDX LDY LDZ
immediate IMM A9 A2 A0 A3
base page BP A5 A6 A4
base page indexed X BP,X B5 B4
base page indexed Y BP,Y B6
absolute ABS AD AE AC AB
absolute indexed X ABS,X BD BC BB
absolute indexed Y ABS,Y B9 BE
base page indexed indirect X (BP,X) A1
base page indirect indexed Y (BP),Y B1
base page indirect indexed Z (BP),Z B2
stack vector indir indexed Y (d,SP),Y E2
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
2 6 stack vector indirect indexed Y
These instructions load the specified register from memory. The
"N" or Negative flag will be set if the bit 7 loaded is a 1. Otherwise
it is cleared. The "Z" or Zero flag is set if all bits loaded are
zero, otherwise, it is cleared.
Flags
N V E B D I Z C
7 - - - - - Z -
Negate (twos complement) accumulator NEG
A=-A
Addressing Mode Opcode Bytes Cycles
implied 42 1 2
The NEG or "negate" instruction performs a two's-complement
inversion of the data in the accumulator. For example, 1 becomes -1,
-5 becomes 5, etc. The same can be achieved by subtracting A from
zero.
The "N" or Negative flag will be set if the accumulator bit 7
becomes a 1. Otherwise it is cleared. The "2" or Zero flag is set if
the accumulator is (and was) zero.
Flags
N V E B D I Z C
N - - - - - Z -
No-operation NOP
Addressing Mode Opcode Bytes Cycles
implied EA 1 1
The NOP no-operation instruction has no effect, unless used
following a MAP opcode. Then its is interpreted as a EOM end-of-map
instruction. (See EOM)
Flags
N V E B D I Z C
- - - - - - - -
Or memory logically with accumulator ORA
A=A.or.M
Addressing Mode Abbrev. Opcode
immediate IMM 09
base page BP 05
base page indexed X BP,X 15
absolute ABS 0D
absolute indexed X ABS,X ID
absolute indexed Y ABS,Y 19
base page indexed indirect X (BP,X) 01
base page indirect indexed Y (BP),Y 11
base page indirect indexed Z (BP),2 12
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
The ORA instructions perform a logical "or" between data bits
fetched from memory and the accumulator bits. The results are then
stored in the accumulator. For either accumulator or corresponding
memory bit that is a logical 1's, the result is a 1. Otherwise it is
0.
The "N" or Negative flag will be set if the bit 7 result is a 1.
Otherwise it is cleared. The "Z" or Zero flag is set if all result
bits are zero, otherwise, it is cleared.
Flags
N V E B D I Z C
N - - - - - Z -
Pull register data from stack PLA PLP PLX PLY PLZ
Opcode
PLA Pull Accumulator from stack 68
PLX Pull index X from stack FA
PLY Pull index Y from stack 7A
PLZ Pull index Z from stack FB
PLP Pull Processor status from stack 28
Bytes Cycles Mode
1 3 register
The Pull register operations, first, increment the stack pointer
SP, and then, load the specified register with data from the stack.
Except in the case of PLP, the "N" or Negative flag will be set
if the bit 7 loaded is a 1. Otherwise it is cleared. The "Z" or Zero
flag is set if all bits loaded are zero, otherwise, it is cleared.
In the case of PLP, all processor flags (P register bits) will be
loaded from the stack, except the "B" or "break" flag, which is always
a 1, and the "E" or "stack pointer Extend disable" flag, which can
only be set by SEE, or cleared by CLE instructions.
Flags
N V E B D I Z C
N - - - - - Z - (except PLP)
7 6 - - 3 2 1 0 (PLP only)
Push registers or data onto stack PHA PHP PHW PHX PHY PHZ
PHA Push Accumulator onto stack
PHP Push Processor status onto stack
PHW Push a word from memory onto stack (also noted as PHD)
PHX Push index X onto stack
PHY Push index Y onto stack
PHZ Push index Z onto stack
Opcodes
Addressing Mode Abbrev. PHA PHP PHW PHX PHY PHZ
register 48 08 DA 5A DB
word immediate IMMw F4
word absolute ABSw FC
Bytes Cycles Mode
1 3 register
3 5 word immediate
3 7 word absolute
These instructions push either the contents of a register onto
the stack, or push two bytes of data from memory (PHW) onto the stack.
If a register is pushed, the stack pointer will decrement a single
address. If a word from memory is pushed ([SP]<-PC(LO),
[SP-1]<-PC(HI)), the stack pointer will decrement by 2. No flags are
changed.
Flags
N V E B D I Z C
- - - - - - - -
Reset memory bits RMB
M=M.and.-bit
Opcode to reset bit
0 1 2 3 4 5 6 7
07 17 27 37 47 57 67 77
Bytes Cycles Mode
2 4 base-page
These instructions reset a single bit in base-page memory, as
specified by the opcode. No flags are modified.
Flags
N V E B D I Z C
- - - - - - - -
Rotate memory or accumulator, left or right ROL ROR ROW
ROL Rotate memory or accumulator left throught carry
ROR Rotate memory or accumulator right throught carry
ROW Rotate memory (word) left throught carry
Opcodes
Addressing Mode Abbrev. ROL ROR ROW
register (A) 2A 6A
base page BP 26 66
base page indexed X BP,X 36 76
absolute ABS 2E 6E EB
absolute indexed X ABS,X 3E 7E
Bytes Cycles Mode
1 1 register
2 4 base page (byte) non-indexed, or indexed X
3 5 absolute non-indexed, or indexed X
2 6 absolute (word)
The ROL instructions shift a single byte of data in memory or the
accumulator left (towards the most significant bit) one bit position.
The state of the "C" or "carry" flag is shifted into bit 0.
The "N" or Negative bit will be set if the result bit 7 is
(operand bit 6 was) a 1. Otherwise, it is cleared. The "Z" or Zero
flag is set if ALL result bits are zero. The "C" or Carry flag is set
if the bit shifted out is (operand bit 7 was) a 1. Otherwise, it is
cleared.
The ROR instructions shift a single byte of data in memory or the
accumulator right (towards the least significant bit) one bit
position. The state of the "C" or "carry" flag is shifted into bit 7.
The "N" or Negative bit will be set if bit 7 is (carry was) a 1.
Otherwise, it is cleared. The "Z" or Zero flag is set if ALL result
bits are zero. The "C" or Carry flag is set if the bit shifted out is
(operand bit 0 was) a 1. Otherwise, it is cleared.
The ROW instruction shifts a word (two bytes) of data in memory
left (towards the most significant bit) one bit position. The state of
the "C" or "carry" flag is shifted into bit 0.
The "N" or Negative bit will be set if the result bit 15 is
(operand bit 14 was) a 1. Otherwise, it is cleared. The "Z" or Zero
flag is set if ALL result bits (both bytes) are zero. The "C" or Carry
flag is set if the bit shifted out is (operand bit 15 was) a 1.
Otherwise, it is cleared.
Flags
N V E B D I Z C
N - - - - - Z C
Return from BRK, interrupt, kernel, or subroutine RTI RTN RTS
Operation description Opcode bytes cycles
RTI Return from interrupt 40 1 5 P,PCw<(SP),SP<SP+3
RTN #n Return from kernel 62 2 7 PCw<(SP)+1,SP<SP+2+N
RTS Return from subroutine 60 1 4 PCw<(SP)+1,SP<SP+2
The RTI or ReTurn from Interrupt instruction pulls P register
data and a return address into program counter bytes PCL and PCH from
the stack. The stack pointer SP is resultantly incremented by 3.
Execution continues at the address recovered from the stack.
Flags
N V E B D I Z C
7 6 - - 3 2 1 0 (RTI only)
The RTS or ReTurn from Subroutine instruction pulls a return
address into program counter bytes PCL and PCH from the stack. The
stack pointer SP is resultantly incremented by 2. Execution continues
at the address recovered + 1, since BSR and JSR instructions set the
return address one byte short of the desire return address.
The RTN or ReTurn from kerNel subroutine is similar to RTS,
except that it contains an immediate parameter N indicating how many
extra bytes to discard from the stack. This is useful for returning
from subroutines which have arguments passed to them on the stack. The
stack pointer SP is incremented by 2 + N, instead of by 2, as in RTS.
Flags
N V E B D I Z C
- - - - - - - - (RTN and RTS)
7 6 - - 3 2 1 0 (RTI)
Subtract memory from accumulator with borrow SBC
A=A-M+C-1
Addressing Mode Abbrev. Opcode
immediate IMM E9
base page BP E5
base page indexed X BP,X F5
absolute ABS ED
absolute indexed X ABS,X FD
absolute indexed Y ABS,Y F9
base page indexed indirect X (BP,X) E1
base page indirect indexed Y (BP),Y F1
base page indirect indexed Z (BP),Z F2
Bytes Cycles Mode
2 2 immediate
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
The SBC instructions subtract data fetched from memory from the contents
of the accumulator, assuming the "C" or "carry" flag was set. If "C" was clear,
an additional count is subtracted. The results of the subtract is stored in
the accumulator. If the "D" or Decimal Mode flag, in the processor status regis-
ter, then a Binary Coded Decimal (BCD) subtract is performed.
The "N" or Negative flag will be set if the difference is negative,
otherwise it is cleared. The "V" or Overflow flag will be set if the sign
of the difference is different from the sign of both operands, indicating a
signed overflow. Otherwise, it is cleared. The "Z" or Zero flag is set if
the difference (stored into the accumulator) is zero, otherwise, it is cleared.
The "C" or carry is set if the unsigned minuend (in the accumulator) is greater-
than or equal-to the unsigned subtrahend (in memory). Otherwise, it is cleared.
Flags
N V E B D I Z C
N V - - - - Z C
Set processor status bits SEC SED SEE SEI
Opcode Cycles Flags
N V E B D I Z C
SEC Set the Carry bit 38 1 - - - - - - - S
SED Set the Decimal mode bit F8 1 - - - - S - - -
SEE Set stack Extend disable bit 03 2 - - S - - - - -
SEI Set Interrupt disable bit 78 2 - - - - - S - -
Bytes Mode
1 implied
All of the P register bit set intructions are a single byte long.
Most of them require a single CPU cycle. The SEE and SEI require 2 cycles.
Set memory bits SMB
M=M.or.bit
Opcode to set bit
0 1 2 3 4 5 6 7
87 97 A7 B7 C7 D7 E7 F7
Bytes Cycles Mode
2 4 base-page
These instructions set a single bit in base-page memory, as
specified by the opcode. No flags are modified.
Flags
N V E B D I Z C
Store registers STA STX STY STZ
STA Store Accumulator to memory M<A
STX Store index X to memory M<X
STY Store index Y to memory M<Y
STZ Store index Z to memory M<Z
Opcodes
Addressing Mode Abbrev. STA STX STY STZ
base page BP 85 86 84 64
base page indexed X BP,X 95 94 74
base page indexed Y BP,Y 96
absolute ABS 8D 8E 8C 9C
absolute indexed X ABS,X 9D SB 9E
absolute indexed Y ABS,Y 99 9B
base page indexed indirect X (BP,X) 81
base page indirect indexed Y (BP),Y 91
base page indirect indexed Z (BP),Z 92
stack vector indir indexed Y (d,SP),Y 82
Bytes Cycles Mode
2 3 base page non-indexed, or indexed X or Y
3 4 absolute non-indexed, or indexed X or Y
2 5 base page indexed indirect X, or indirect indexed Y or Z
2 6 stack vector indirect indexed Y
These instructions store the specified register to memory. No
flags are affected.
Flags
N V E B D I Z C
- - - - - - - -
Transfers (between registers) TAB TAX TAY TAZ
TBA TSX TSY TXA
TXS TYA TYS TZA
Operation Flags Transfer
Symbol Code N V E B D I Z C from to
TAB 5B - - - - - - - - accumulator base page reg
TAX AA N - - - - - Z - accumulator index X reg
TAY A8 N - - - - - Z - accumulator index Y reg
TAZ 4B N - - - - - Z - accumulator index Z reg
TBA 7B N - - - - - Z - base page reg accumulator
TSX BA N - - - - - Z - stack ptr low index X reg
TSY 0B N - - - - - Z - stack ptr high index Y reg
TXA 8A N - - - - - Z - index X reg accumulator
TXS 9A - - - - - - - - index X reg stack ptr low
TYA 98 N - - - - - Z - index Y reg accumulator
TYS 2B - - - - - - - - index Y reg stack ptr high
TZA 6B N - - - - - Z - index Z reg accumulator
These instructions transfer the contents of the specified source
register to the specified destination register. Any transfer to A, X,
Y, or Z will affect the flags as follows. The "N" or "negative" flag
will be set if the value moved is negative (bit 7 set), otherwise, it
is cleared. The "Z" or "zero" flag will be set if the value moved is
zero (all bits 0), otherwise, it is cleared. Any transfer to SPL or
SPH will not alter any flags.
************************************************************
* WARNING *
* *
* If you are using Non-Maskable-Interrupts, or Interrupt *
* Request is enabled, and you want to change BOTH stack *
* pointer bytes, do not put any code between the TXS and *
* TYS opcodes. Taking this precaution will prevent any *
* interrupts from occuring between the setting of the *
* two stack pointer bytes, causing a potential for *
* writing stack data to an unwanted area. *
************************************************************
Bytes Cycles Mode
1 1 register
Test and reset or set memory bits TRB TSB
TRB Test and reset memory bits with accumulator (M.or.A),M<M.and.-A
TSB Test and set memory bits with accumulator (M.or.A),M<M.or.A
Opcodes
Addressing Mode Abbrev. TRB TSB
base page BP 14 04
absolute ABS 1C OC
These instructions test and set or reset bits in memory, using
the accumulator for both a test mask, and a set or reset mask. First,
a logical AND is performed between memory and the accumulator. The "Z"
or "zero" flag is set if all bits of the result of the AND are zero.
Otherwise it is reset.
The TSB then performs a logical OR between the bits of the
accumulator and the bits in memory, storing the result back into
memory.
The TRB, instead, performs a logical AND between the inverted
bits of the accumulator and the bits in memory, storing the result
back into memory.
Bytes Cycles Mode
2 4 base page non-indexed
3 5 absolute non-indexed
Flags
N V E B D I Z C
- - - - - - Z -
2.3.7.6. 4502 Opcode Table
0 1 2 3 4 5 6 7 8 9 A B C D E F
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BRK |ORA |CLE*|SEE*|TSB |ORA |ASL |RMB0|PHP |ORA |ASL |TSY*|TSB |ORA |ASL |BBR0|
| |INDX| | |ZP |ZP |ZP |ZP | |IMM | | |ABS |ABS |ABS |ZP | 0
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BPL |ORA |ORA |BPL*|TRB |ORA |ASL |RMB1|CLC |ORA |INC |INZ*|TRB |ORA |ASL |BBR1|
|REL |INDY|INDZ|WREL|ZP |ZPX |ZPX |ZP | |ABSY| |ABS |ABSX|ABSX|ZP | 1
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|JSR |AND |JSR*|JSR*|BIT |AND |ROL |RMB2|PLP |AND |ROL |TYS*|BIT |AND |ROL |BBR2|
|ABS |INDX|IND |INDX|ZP |ZP |ZP |ZP | |IMM | | |ABS |ABS |ABS |ZP | 2
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BMI |AND |AND |BMI*|BIT |AND |ROL |RMB3|SEC |AND |DEC |DEZ*|BIT |AND |ROL |BBR3|
|REL |INDY|INDZ|WREL|ZPX |ZPX |ZPX |ZP | |ABSY| | |ABSX|ABSX|ABSX|ZP | 3
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|RTI |EOR |NEG*|ASR*|ASR*|EOR |LSR |RMB4|PHA |EOR |LSR |TAZ*|JMP |EOR |LSR |BBR4|
| |INDX| | |ZP |ZP |ZP |ZP | |IMM | | |ABS |ABS |ABS |ZP | 4
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BVC |EOR |EOR |BVC*|ASR*|EOR |LSR |RMB5|CLI |EOR |PHY |TAB*|MAP*|EOR |LSR |BBR5|
|REL |INDY|INDZ|WREL|ZPX |ZPX |ZPX |ZP | |ABSY| | | |ABSX|ABSX|ZP | 5
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|RTS |ADC |RTN*|BSR*|STZ |ADC |ROR |RMB6|PLA |ADC |ROR |TZA*|JMP |ADC |ROR |BBR6|
| |INDX| |WREL|ZP |ZP |ZP |ZP | |IMM | | |IND |ABS |ABS |ZP | 6
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BVS |ADC |ADC |BVS*|STZ |ADC |ROR |RMB7|SEI |ADC |PLY |TBA*|JMP |ADC |ROR |BBR7|
|REL |INDY|INDZ|WREL|ZPX |ZPX |ZPX |ZP | |ABSY |INDX|ABSX|ABSX|ZP | 7
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BRU |STA |STA*|BRU*|STY |STA |STX |SMB0|DEY |BIT |TXA |STY*|STY |STA |STX |BBS0|
|REL |INDX|IDSP|WREL|ZP |ZP |ZP |ZP | |IMM | |ABSX|ABS |ABS |ABS |ZP | 8
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BCC |STA |STA |BCC*|STY |STA |STX |SMB1|TYA |STA |TXS |STX*|STZ |STA |STZ |BBS1|
|REL |INDY|INDZ|WREL|ZPX |ZPX |ZPY |ZP | |ABSY| |ABSY|ABS |ABSX|ABSX|ZP | 9
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|LDY |LDA |LDX |LDZ*|LDY |LDA |LDX |SMB2|TAY |LDA |TAX |LDZ*|LDY |LDA |LDX |BBS2|
|IMM |INDX|IMM |IMM |ZP |ZP |ZP |ZP | |IMM | |ABS |ABS |ABS |ABS |ZP | A
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BCS |LDA |LDA |BCS*|LDY |LDA |LDX |SMB3|CLV |LDA |TSX |LDZ*|LDY |LDA |LDX |BBS3|
|REL |INDY|INDZ|WREL|ZPX |ZPX |ZPY |ZP | |ABSY| |ABSX|ABSX|ABSX|ABSY|ZP | B
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|CPY |CMP |CPZ*|DEW*|CPY |CMP |DEC |SMB4|INY |CMP |DEX |ASW*|CPY |CMP |DEC |BBS4|
|IMM |INDX|IMM |ZP |ZP |ZP |ZP |ZP | |IMM | | ABS|ABS |ABS |ABS |ZP | C
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BNE |CMP |CMP |BNE*|CPZ*|CMP |DEC |SMB5|CLD |CMP |PHX |PHZ*|CPZ*|CMP |DEC |BBS5|
|REL |INDY|INDZ|WREL|ZP |ZPX |ZPX |ZP | |ABSY| | |ABS |ABSX|ABSX|ZP | D
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|CPX |SBC |LDA*|INW*|CPX |SBC |INC |SMB6|INX |SBC |EOM |ROW*|CPX |SBC |INC |BBS6|
|IMM |INDX|IDSP|ZP |ZP |ZP |ZP |ZP | |IMM |NOP |ABS |ABS |ABS |ABS |ZP | E
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|BEQ |SBC |SBC |BEQ*|PHW*|SBC |INC |SMB7|SED |SBC |PLX |PLZ*|PHW*|SBC |INC |BBS7|
|REL |INDY|INDZ|WREL|IMM |ZPX |ZPX |ZP | |ABSY| | |ABS |ABSX ABSX|ZP | F
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
2.4. The CSG 4567 System/Video Controller
2.4.1. Description
The CSG 4567 is a low-cost high-peformance system/video
controller, designed to be used in a wide variety of low-end
home-computer type systems ranging from joystick controlled video
games to high-end home-productivity machines with built-in disk drives
and monitor. The 4567 was designed with Commodore-64 (C64)
architecture as a subset of its advanced features. In addition to
having all of the C64 video modes, it also supports the character
attributes -- blink, bold, reverse video, and underline, and can
display any of the new or old video modes in 80 column or 640
horizontal pixel format, as well as the older 40 column 320 pixel
format.
A new "bitplane" video mode was added to allow the displaying of true
bitplane type video, with up to eight bitplanes in 320 pixel mode and
up to four in 640 pixel mode. The 4567 can also time-multiplex the
bitplanes to give a true four-color 1280 pixel picture. Vertical
resolution is maintained at 200 lines as standard, but can be doubled
to 400 with interlace.
2.4.2. CSG 4567 Pin Assignments
(*** Pinout will change with 4567R7 ***)
R B G C S F S R R R I I N A R N E G E S V
V V V V Y G I O O O O O O E W O X A X I C
I I I I N B D M M M 2 1 I C M R M P D C
D D D D C G * L H * * * 0 A O E N C
E E E E * * P M D L
0 0 0 0 * K
7 7 7 7 7 8 8 8 8 1 1
5 6 7 8 9 0 1 2 3 4 1 2 3 4 5 6 7 8 9 0 1
PSYNC 74 +---------------------------------------+ 12 CAS*
CASS 73 | | 13 CASB*
DISK* 72 | | 14 CASA*
MEMCLK 71 | | 15 RAS*
VCC 70 | | 16 CPUCLK
D0 69 | | 17 DOTCLK
E0 68 | | 18 XTAL14
D1 67 | | 19 XTAL17
E1 66 | | 20 MA0
D2 65 | | 21 MA1
E2 64 | CSG 4567 | 22 MA2
D3 63 | | 23 MA3
E3 62 | | 24 MA4
D4 61 | | 25 MA5
E4 60 | | 26 MA6
D5 59 | | 27 MA7
E5 58 | | 28 MB7
D6 57 | | 29 MB6
E6 56 | | 30 MB5
D7 55 | | 31 A16
E7 54 +---------------------------------------+ 32 A15
5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3
3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3
V I R L E E A A A A A A A A A A A A A A A
S R E P X X 0 1 2 3 4 5 6 7 8 9 1 1 1 1 1
S Q S * T T 0 1 2 3 4
* * H V
* *
2.4.3. CSG 4567 Operation
The 4567 accesses two 8-bit memory blocks, which are up to 64K
each, via two 8-bit bidirectional busses. These are D0-D7 and E0-E7.
The D0-D7 bus is common with the CPU chip, ROM, SID, and the expansion
port, and is used for system memory and bitplanes. The E0-E7 port is
only connected to RAM. This RAM is used for COLOR RAM, attribute RAM,
system memory, and bitplanes.
To access these RAMs, the 4567 has two multiplexed address
busses. These are MA0-MA7, and MB5-MB7. Lines MA0-MA4 are common to
both 64K banks of RAM, but MA5-MA7 go only to bank A, and MB5-MB7 go
only to bank B.
There are four types of DMA accesses which the 4567 can perform.
Remember that RAS* is asserted on every memory clock cycle. These
are...
mode operation CASA* CASB* ROM*
1. 4567 reading both banks X X
2. 4567 reading bank "A" X
3. 4567 reading ROM X
4. 4567 doing refresh
There are six types of CPU routings to RAM and peripheral devices
that are handled by the 4567.
mode operation CASA* CASB* ROM*
2. CPU reading bank "A" X
3. CPU reading bank "B" X
4. CPU writing bank "A" X
5. CPU writing bank "B" X
6. CPU reading ROM X
7. CPU accessing I/O1, I/O2,
SID, ROMH, ROML
There are four basic data routings through the 4567 chip. Three
internal signals route the data busses. WTREG (write 4567 register)
enables routing the external D0-D7 bus to the internal register data
bus. It is normally a logic 1. When it is brought low, the internal
bus disconnects, and the DO-D7 bus output drivers turn on. This is for
CPU reads of 4567 registers or "B" bank RAM. RDBMEM (read "B" bank
memory) routs the E0-E7 data bus to the inputs of the D0-D7 bus output
drivers when at logic level 1. This is for CPU reads of "B" bank RAM.
When 0, (normal) the internal register data bus is routed to the
D0-D7 bus output driver inputs, instead. WTBMEM (write B" bank memory)
turns on the E0-E7 bus drivers, which directly routs the D0-D7 data
bus to the E0-E7 bus when 1. This is for CPU writes to the "B" bank
RAM. When 0, (normal) the E0-E7 bus is input only.
mode operation Wtreg RdBmem WtBmem
1. CPU write 4567 register,
CPU access external,
4567 DMA, etc 1 0 0 (default)
2. CPU read 4567 register 0 0 0
3. CPU read B RAM 0 1 0
4. CPU write B RAM 1 0 1
DMA and Special CPU Accesses
VMF -- Video Matrix Fetch
The 4567 performs Video Matrix Fetches, during displayed video
times, in all of the original VIC-II modes (SCM, MCM, ECM, BMM). This
is true for both 40 and 80 column (320 and 640 pixel) modes. During
VMF, the 4567 reads -- both banks (A & B) of memory over both data
busses D0-D7 and E0-E7. The D0-D7 bus provides the video matrix data,
E0-E3 provides color data, and E4-E7 provides character attribute
data.
CDF -- Character Data Fetch
The 4567 performs Character Data Fetches immediately after each
Video Matrix Fetch in the original VIC-II modes except bitmap mode.
During this fetch Character image data is fetched from ROM or RAM bank
A over the D0-D7 bus.
BMF -- BitMap Fetch
The 4567 performs Bitmap Data Fetches immediately after each
Video Matrix Fetch, only in the bitmap mode. During this fetch. Bitmap
image data is fetched from RAM bank A over the D0-D7 bus.
BPF -- BitPlane Fetch
The 4567 can perform Bitplane image fetches during displayed
video times, if the Bitplane mode (BPM) is enabled. The number and
position of these fetches is determined by which bitplanes are
enabled. During bitplane fetches, even numbered bitplane data is
fetched over D0-D7 and odd numbered bitplane data is fetched over
E0-E7.
RF -- RAM refresh
The 4567 performs six cycles of dynamic RAM refresh every scanned
video line. During this time no data is fetched and CASA* and CASB*
are not activated.
SPF -- Sprite Pointer Fetch
Up to eight Sprite Pointer Fetches can occur each scanned video
line. One SPF is generated for each sprite that is enabled and
currently being displayed. During an SPF, the pointer to the sprite
image data is fetched from the video matrix area of memory for the
sprite in question over the D0-D7 data bus.
SDF -- Sprite Data Fetch
Three Sprite Data Fetches follow each Sprite Pointer Fetch.
During this time, sprite image data for the sprite in question is
fetched over the D0-D7 data bus.
DAT -- Display Address Translation
Display Address Translation, or DAT fetches, are not actually
DMA-type accesses, but rather CPU address redirections to RAM. In this
case, the unmultiplexed address bus is totally separated from the
multiplexed address bus.
COL -- Color RAM accesses
Color RAM is also accessed by the CPU via an address translation.
This is because color RAM would otherwise be located in the I/O area.
Contents of the Internal A and B Memory
Address Busses Prior to Multiplexing
Signal "VMF" "CDF" "BMF" "BPF" "RF" "SPF" "SDF" "DAT" "COL"
------ ----- ----- ----- ----- ---- ----- ----- ----- -----
IA0 VC0 RC0 RC0 RC0 RF0 SF0 SD0 DT0 A0
IA1 VC1 RC1 RC1 RC1 RF1 SF1 SD1 DT1 A1
IA2 VC2 RC2 RC2 RC2 RF2 SF2 SD2 DT2 A2
IA3 VC3 D0 VC0 VC0 RF3 1 SD3 DT3 A3
IA4 VC4 D1 VC1 VC1 RF4 1 SD4 DT4 A4
IA5 VC5 D2 VC2 VC2 1 1 SD5 DT5 A5
IA6 VC6 D3 VC3 VC3 1 1 DO DT6 A6
IA7 VC7 D4 VC4 VC4 1 1 Dl DT7 A7
IA8 VC8 D5 VC5 VC5 1 1 D2 DT8 A8
IA9 VC9 D6 VC6 VC6 1 1 D3 DT9 A9
IA10 VM0/VC10 D7 VC7 VC7 RF5 VM0/1 D4 DT10 A10
IA11 VM1 CBO VC8 VC8 RF6 VM1 D5 DT11 1
IA12 VM2 CB1 VC9 VC9 RF7 VM2 D6 DT12 1
IA13 VM3 CB2 CB2/VC10 BE13/VC10 1 VM3 D7 BE13/DT13 1
IA14 VBO VBO VBO BE14 1 VBO VBO BE14 1
IA15 VB1 VB1 VB1 BE15 1 VB1 VB1 BE15 1
IA16 A16 A16 A16 A16 RF8 A16 A16 DT16 1
IB10 0/* * * * * * * * *
IB11 1 * * * * * * * 1
IB12 1 * * * * * * * 1
IB13 1 * * B013/* * * * B013/* 1
IB14 1 * * B014 * * * B014 1
IB15 1 * * B015 * * * B015 1
DMA 1 1 1 1 1 1 1 0 0
Legend :
------------------------------------------
VC = Video Matrix Counter
RC = Row Counter
VM = Video Matrix Address
VB = Video Bank Address
CB = Character Generator Bank Address
RF = Refresh Counter
SF = Sprite Pointer Fetch Counter
SD = Sprite Data Fetch Counter
DT = Display Address Translator
BE = Bitplane Even Pointer
BO = Bitplane Odd Pointer
A = Address Out = Address In
D = Data fetched from previous fetch
* = "B" bus contents, same as "A" bus
xxx/yyy = contents for 320/640 pixel modes
Multiplexed Address Bus Generation
The A and B memory address busses are multiplexed 2:1 to generate
the MA and MB multiplexed address busses. Listed below are the primary
addresses used to generate the multiplexed row and column addresses.
signal row column
------ --- ------
MA0 A0 A5
MA1 A1 A6
MA2 A2 A7
MA3 A3 A8
MA4 A4 A9
MA5 A10 A13
MA6 A11 A14
MA7 A12 A15
MB5 B10 B13
MB6 B11 B14
MB7 B12 B15
ROM physical addresses
0000 New area A
2000 Basic
4000 New area B
5000 Character sets
6000 Kernel
ROM can appear (to the 4567) at 1000-1FFF (bank 0)
and 9000-9FFF (bank 2)
The ROM address translates to 5000-5FFF
Contents of Memory map based on Loram, Hiram, Game, and Exrom
L H G E Area
O I A X
R R M R /ROML /ROMH /ROMH
A A E O 0000- 8000- A000- C000- D000- E000-
M M M 7FFF 9FFF BFFF CFFF- DFFF FFFF
- - - - ----- ----- ----- ----- ----- -----
X X 0 1 4KRAM EXT NADA NADA I/O EXT
0 0 1 X RAM RAM RAM RAM RAM RAM
0 0 X 0 RAM RAM RAM RAM RAM RAM
0 1 0 0 RAM RAM EXT RAM I/O ROM
0 1 1 X RAM RAM RAM RAM I/O ROM
1 0 0 0 RAM RAM RAM RAM I/0 RAM * CG ROM off
1 0 1 X RAM RAM RAM RAM I/O RAM
1 1 0 0 RAM EXT EXT RAM I/O ROM
1 1 1 0 RAM EXT ROM RAM I/O ROM
1 1 1 1 RAM RAM ROM RAM I/O ROM
Color Palette ROM Programming
index red green blue fg/bg I Q Y color
----- ----- ----- ----- ----- ----- ----- ----- -------
0 0 0 0 0 0 0 0 black
1 15 15 15 1 0 0 1.0 white
2 15 0 0 1 .60 .21 .30 red
3 0 15 15 1 -.60 -.21 .70 cyan
4 15 0 15 1 .28 .52 .41 magenta
5 0 15 0 1 -.28 -.52 .59 green
6 0 0 15 1 -.32 .31 .11 blue
7 15 15 0 1 .32 -.31 .89 yellow
8 15 6 0 1 .49 0 -.54 orange
9 10 4 0 1 .33 0 .36 brown
10 15 7 7 1 .32 .11 .63 pink
11 5 5 5 1 0 0 .33 dark grey
12 8 8 8 1 0 0 .53 medium, grey
13 9 15 9 1 -.11 -.21 .84 light green
14 9 9 15 1 -.13 -.12 .64 light blue
15 11 11 11 1 0 0 .73 light, grey
Horizontal Sync Counter Events (assuming HPOS reg=0)
For NTSC the first 390 HCOUNT steps are at half the primary clock
rate, and 390 are at the primary clock rate, giving 520 counts for 910
clocks. For PAL the first 388 HCOUNT steps are at the slow rate, and
132 are at the faster clock rate, giving 520 counts for 908 clocks.
EVENT Clock +256 /2 HCOONT Duration
----- ----- ---- ---- ------ --------
VSYNC1 START 513 769 384 384 846 59us
VSYNC1 STOP 449 705 352 352
VSYNC2 START 58 314 157 157 846 59us
VSYNC2 STOP 904 250 W 125 125
HSYNC START 513 769 384 384 63 4.4us
HSYNC STOP 576 832 416 442
HEQU1 START 513 769 384 384 36 2.5us
HEQU1 STOP 549 805 402 414
HEQU2 START 58 314 157 157 36 2.5us
HEQU2 STOP 94 350 175 175
BURST START 576 832 416 442 47 3.3us
BURST STOP 623 879 439 488
HBLANK START 478 734 367 367 175 12.2us
HBLANK STOP 653 909 454 518
Horizontal DMA Counter Events
(these are actual counts - decode 1 count earlier)
EVENT HCOUNT
----- ------
HDMAEN START 15 19 (640 mode)
HDMAEN STOP 335 339 (640 mode)
HDEW START 25 32 (38 col)
HDEN STOP 345 336 (38 col)
HPIXEN START 24
HPIXEN STOP 344
SPR GO 358
SPR STOP 359
SPR CLOCK DIS 360
SPR CLOCK ENA 488
SPR DMA START 372 (and EOL)
SPR DMA STOP 482
REFRESH START 482
REFRESH STOP 506
VINC 370
HRES 15
DOG START 16
DOG STOP 376
SYNCO 0
SYNC1 1
SYNC2 3
FAST 390 NTSC 388 PAL
Vertical Timings
When the vertical position register VPOS is set to zero by the
CPU, it actually is storing a compare value of 128, since the MSB of
VPOS is inverted. This actually corresponds to raster count 256, since
the vertical event counter is counting half-lines. When the vertical
event counter matches the VPOS register, the vertical sync. counter is
reset to zero. Multiply the desired line for each event by 2 and
subtract the nominal VPOS value of 256 to get the desired decode. If
the result is negative add the modulo of the vertical event counter,
which is 525 for NTSC and 625 for PAL. The "line" in these tables
refer to raster lines, where line 50. is the first displayed line in a
25 row display.
NTSC
Event line v count - vpos decode
----- ---- ------- ------ ------
VSYNC START 11 22 -234 291
VSYNC STOP 14 28 -228 297
VEQU START 8 16 -240 285
VEQU STOP 17 34 -222 303
VBLANK START 8 16 -240 285
VBLANK STOP 28 56 -200 325
EARLY START 64 128 -128 397
EARLY STOP 11 22 -234 291
LATE START 11 23 -233 292
LATE STOP 3 6 -250 275
PAL -- timings begin 25 lines before NTSC because of 50 extra lines
Event line v count - vpos decode
----- ---- ------- ------ ------
VSYNC START -14 -29 -285 340
V&YNC STOP -11 -24 -280 345
VEQU START -17 -34 -290 335 *equ/sync is 15 half-lines
VEQU STOP -9 -19 -275 350 *for pal
VBLANK START -17 -34 -290 335
VBLANK STOP 3 6 -250 375
EARLY START 39 78 -176 447
EARLY STOP -14 -29 -285 340
LATE START -14 -28 -284 341
LATE STOP -22 -44 -300 325
Note : EARLY and LATE active concurrently indicate GROSS.
Divide ratios (including external sync values)
Counter Normal Early Late Gross
------- ------ ----- ---- -----
NTSC vertical 525 524 526 540
PAL vertical 625 624 626 640
NTSC horizontal 910 908 912
PAL horizontal 908 906 910
horizontal counter 520 519 521
Number of cycles per line
In "slow" CPU mode...
Total cycles no video 65
40 column SCM, MCM, ECM, BMM,
320 pixel BPM, BP0-BP3 only, or
640 pixel BPM, BP0-BP1 only no cost 0
80 column SCM, MCM, ECM, BMM,
320 pixel BPM, BP0-BP7, or
640 pixel BPM, BP0-BP3 subtract 40
Sprites subtract 2 per active sprite
Examples...
No video on line 65
40 column text or equiv. BPs (no sprites) 65
80 column text or equiv. BPs (no sprites) 25
80 column text or equiv. BPs, all sprites 9 -- worst case
227 memory cycles/line
6 refresh
0-32 sprite
0,40,80,120,160 video
fast slow
---- ----
277 138 total cycles/line
-6 -3 refresh
-32 -16 sprites
---- ----
239 119 avail CPU cycles/line (no video)
no 1 2 3 4
video fetch fetch fetch fetch
------ ------ ------ ------ ------
cpucyc 239 199 159 119 79 all sprites (fast)
cpucyc 271 231 191 151 111 no sprites (fast)
cpucyc 119 79 79 39 39 all sprites (slow)
cpucyc 135 95 95 55 55 no sprites (slow)
2.4.4. Programming the new VIC (4567)
The C4567R6 is a high performance single chip video controller
designed to bring exceptional graphics to low cost computer and game
systems. It presently is available in NTSC and PAL versions to match
European and North American television standards.
The following are new features that are added as a superset of
the old VIC-II video controller functions incorporated in the C4567R6.
a. NewVic mode
b. 80 column character and 640 horizontal pixel mode
c. Scan interlace and 400 line mode
d. Character attributes (blink, highlight, underline, reverse).
e. Fast clock mode (3.58 vs. 1.02 MHz)
f. Bitplane mode
g. Color palettes
h. Additional ROM
i. 1280H pixel mode
j. Display Address Translator (DAT)
k. Horizontal and vertical positioning
1. External sync (Genlock)
m. Alternate character set
n. Chroma killer
NewVic Mode
After power-up and reset, the C4567R6 performs as if it were the
"old" VIC chip. In this mode, none of the new features are accessible.
The old VIC II registers appear at addresses $D000-$D3FF, echoed 16
times, every 64 addresses, and any new registers within the 64 byte
block will not exist.
To put the C4567R6 into "NewVic" mode, the user must write first
an $A5 and then a $96 to the KEY register ($D02F). Once these values
have been entered the C4567R6 will be in "NewVic" mode, and access to
the "NewVic" registers and modes will be possible.
To take the C4567R6 out of "NewVic" mode, simply write any value
to the KEY register. After doing this, all of the new modes will be
disabled. The registers that were programmed in "NewVic" mode will
retain their current values. It should be noted, however, that since
all old modes are available in new mode, there is little reason to
exit new mode.
80 Column (character) or 640 Pixel (bitmap or bitplane) Mode.
You can put the C4567R6 into "80 Column Mode" or "640 horizontal
pixel mode" by setting the H640 bit in control register "B". The
normal horizontal rendering is 40 columns or 320 pixels.
In 80 column character mode, several things change. The Video
Matrix becomes 2K bytes long, where it used to be 1K in 40 column
mode. The character color RAM also becomes 2K bytes long. The
locations of these areas do not change from the prior convention,
except that the low order video matrix address bit is not used in 80
column mode. Where the programmer used to have 16 choices for locating
the Video Matrix within a video bank, in 80 column mode there are only
8 choices.
Although the color RAM doubles in size to 2K bytes, the area
provided for color RAM in the I/O map only allows for 1K of color RAM.
To read or write the second 1K of color RAM requires that you move
CIA1, CIA2, I/O1, and I/O2 out of the way. To do this, set the "COLOR
RAM @DC00" bit in Control Register "A".
In 640 pixel bitmap mode, similar changes occur. The video matrix
and color RAM double in size and are positioned in the memory map
exactly as is done in 80 column character mode. The bitmap must now
also double in size from 8K to 16K bytes. Because the total memory
that the video matrix and the bitmap would require now exceeds the
normal 16K byte video bank size, the video bank size has been doubled
from 16K to 32K for the bitmap only. The least significant video bank
bit is ignored, and the high order character generator bank bit
selects which half of the 32K video bank that bitmaps will be fetched
from. The video matrix is still fetched from the normal 16K video
bank.
In 80 column or 640 pixel mode, the sprite pointers are at the
end of the 2K byte video matrix, where they used to be at the end of
the 1K byte video matrix, in 40 column or 320 pixel mode. The size,
location, and resolution of sprites are not affected by any of the
mode switches.
Interlace, and 400 Line Vertical mode
The C4567R6 can interlace scan lines to give a true NTSC, 525
line screen (625 lines on PAL versions), although the default,
however, is a 262 line non-interlaced screen (312 lines on PAL
versions). Set the INT bit in control register "B" to a "1" if you
want interlacing.
The C4567R6 can also give a 400 line vertical resolution, which
is useful in the new Bitplane mode. Set the V400 bit, and the INT bit
in control register "B" to a "1" to enable 400 line bitplanes. (see
Bitplanes, below) The V400 switch will have no effect if the display
is not interlacing. Also, although interlacing is permitted in all of
the old video modes, the same data will appear on both odd and even
rasters, even if the V400 switch is on.
1280 Horizontal Pixel mode
The C4567R6 supports ultra-high resolution graphics by permitting
the programmer to use 1280 pixel lines. This is enabled by setting the
H1280 and H640 bits in control register "B" to a "1".
The 1280 pixels are acheived by time-multiplexing bitplane bits.
This is done by substituting the pixel clock for bitplane 7. This
means that for the first half of each pixel, the color palette will be
fed the normal color index. For the second half of the same pixel, it
will fed the normal index, plus 128. To utilize this feature, the user
must program the color palette to perform the multiplexing function.
The H1280 bit can also be set H640 off. This is a unique mode
that allows the use of 320 and 640 horizontal pixel bitplanes
simultaneously.
Character Attributes
In NewVic mode, the C4567R6 supports four new character
attributes which can be enabled by setting the ATTR bit in Control
Register "B". These are Blink, Highlight, Underlined, and Reverse
Video characters. Any combination of these attributes can be enabled
on a character by character basis, at any time. Certain combinations
will have varying effects. (See table below) Attributes can also be
applied to bitmap mode, and, to a limited extent, to the new bitplane
mode. (see Bitplanes, below)
Blink is enabled by setting bit 4 of the Color RAM location for
each character requiring this attribute. The Blink attribute will
either flash the character on and off, or will alternately enable and
disable the other attributes, if any are selected. The blink rate is
approximately 1 Hz.
Reverse Video is enabled by setting bit 5 of the Color RAM
location for each character requiring this attribute. Reverse Video is
achieved by simply complementing the character image data for each
character with this attribute. If the character is also underlined,
the underline will be reversed, as well. Highlighted characters also
will reverse. Blink, if enabled, will alternately enable and disable
this attribute.
Highlight is enabled by setting bit 6 of the Color RAM location
for each character requiring this attribute. Highlight is achieved by
adding 16 to the color index value. As in the past, the character
color is determined by the index value stored in bits 0-3 of the color
RAM. In many respects, bit 6 is merely another color select bit. What
differs is that the Blink attribute can be used to blink between the
"normal" color, and the "highlight" color. Both the character image,
and its background can have unique highlight colors.
To use the highlight attribute, effectively, color palette
locations 16 through 31 should be programmed to "highlight" colors.
(see Palette, below). Highlight colors don't have to be related to
normal colors, but can be anything.
Underline is enabled by setting bit 7 of the Color RAM location
for each character requiring this attribute. Underline is accomplished
by forcing "1" character image data on the eighth raster line for each
character with this attribute. If the Blink attribute is also
selected, the underline will blink.
Summary of Character Attributes and their Effects
Underline Hilite Reverse Blink Effect
--------- ------ ------- ----- -----------------------
off off off off normal character
off off off on blinking character
off off on off reverse video character
off off on on alternate reverse/normal
off on off off highlight character
off on off on alternate highlight/normal
off on on off highlight, reverse video
off on on on alternate highlight-reverse/normal
on off off off underlined character
on off off on normal char with blinking underline
on off on off underlined reverse-video
on off on on alternate underline-reverse/normal
on on off off highlight underlined character
on on off on alternate highlight-underline/normal
on on on off highlight underlined reversed
on on on on alternate hilite-underlined-rev/normal
Fast Clock
To permit the new system to run certain types of the old C64
software, the C4567R6 provides a normal (slow) CPU clock with a long
term (63us) average of 1.02 Mhz (exactly the C64 clock rate). This is
accomplished by setting up a pattern of 1.79Mhz (560ns) cycles to give
a total of 65 cycles be horizontal scanning line (also, like C64). In
addition/logic is provided on the C4567R6 to determine when the
microprocessor chip is executing an enhanced opcode, and, if so,
subtracts a clock cycle from it.
By setting the FAST bit in Control Register "B", you can instruct
the C4567R6 to clock the CPU at 3.58 Mhz, and permit the
microprocessor to execute its enhanced instructions at full speed.
This can increase CPU speed up to 400%.
BitPlane mode
In addition to the usual video modes provided by the old VIC
chip, the C4567R6 provides a bitpiane mode, which allows up to eight
bitplanes to be used in the 320, or up to four bitplanes to be used in
the 640 horizontal pixel modes.
Enabling BitPlane mode is done by setting the BPM bit in Control
Register "B". Doing this will override all of the other video modes.
To specify which bitplanes (0-7) to use, set the corresponding bit for
each bitplane you want, in the Bitplane Enable register. Bitplane mode
may be used with sprites. Bitplane 2 is the foreground/background
plane used for sprite/background collision detection and priority.
The bitplanes, whether enabled, or not, provide the eight color
value bits used to define what color will be displayed for any pixel
on the screen. Bitplane 0 provides the least significant bit of the
color value, and bitplane 7 provides the most significant bit.
Bitplanes that are not enabled will contribute a "0" to their bit
position in the color select code, unless the complement bit for that
bitplane, in the complement register, is set.
Any bitplane's data can be inverted, whether or not the bitplane
is enabled by setting its respective bit in the Bitplane Complement
register. Inversion on unenabled bitplanes will cause them to
contribute a "1" instead of their usual "0".
In BitPlane mode, the C4567R6 does not use the Video Bank select
bits, like the old VIC chip did. Instead, you can specify which 8k
block (in 320 mode), or which 16k block (in 640 mode) of memory you
want a bitplane to come out of. Specify where you want the bitplanes
to be fetched from, using Bitplane Address registers 0 through 7.
Note, however, that the least significant bits of these registers are
ignored in 640 pixel mode, and that register 4 through 7 are never
used in 640 pixel mode. Even numbered bitplanes can only be fetched
from memory bank 0 (addresses 0-FFFF hex), and odd numbered bitplanes
can only be fetched from memory bank 1 (addresses 10000-1FFFF hex).
So, the bitplane pointers define which section within the confined
bank that bitplane data will be fetched from.
In the Bitplane address registers, there are two bit-fields. One
field of bits is for the even vertical scan, and the other field of
bits is for the odd scan. The odd scan bits are not used unless both
INT and V400 bits are set in control register "B".
Attributes can be enabled in bitplane mode by setting the ATTR
bit in control register "B". If this is done, the most significant
nybble of bytes fetched for bitplane 3 will contain the attribute
specification for each 8 by 8 pixel cell, exactly as is done in
character modes. One exception is that the "hilite" attribute will be
disabled. The attributes are only applied to bitplane 2, which is also
the foreground/background plane for sprite collisions and priority
purposes.
To properly utilize this feature, bitplane 2 must be enabled to
provide attributed bitplane data, and bitplane 3 must be disabled,
since it will be providing attribute data. Data fetches for the
attribute data will occur, because bitplanes 2 and 3 are both fetched
in the same memory cycle. You may also enable any other bitplanes as
needed. Bitplane 2, and any other bitplane may be complemented, but
complementing bitplane 3 will only cause its bit weight to contribute
a "1", and will not invert the attribute data.
Note:
Addresses 1F800-1FFFF hex are the Color and Attribute RAM used in
the old video modes. You can use this area for bitplane if you do not
plan on switching between old and new video modes and expect the data
for both modes to be there.
Color Palette
The C4567R6, allows the programmer to use the sixteen standard
"C64" colors, or define up to 256 custom colors and/or use the palette
to perform boolean operations on the bitplane data. The C4567R6
incorporates a 16 word palette ROM and a has a 256 word palette RAM.
Each palette location is an index, which can specify one of sixteen
possible intensity values (4 bits) each, of Red, Green, and Blue
primary colors, plus a single control bit (FGBG) which can be used for
foreground/background control for video mixing applications, or to
drive a separate monochrome screen.
The first 16 locations of the palette default to the C64 colors
in ROM. The remaining 240 locations are programmable RAM. The first 16
locations can also be replaced with RAM, however, by setting the PAL
bit in control register "B". All old video modes, including sprites
and exterior, can only access the lowest 16 palette locations (except
hilite cells), so you may want to reserve these indices for such
features.
Only bitplane mode can make full use of all palette locations.
Even when less than eight bitplanes are used, the bitplane complement
bits of the unused bitplanes can be used to specify which part of the
palette is to be used. This feature allows the programmer to define
multiple sub-palettes, which can be switched between quickly, or to
specify an offset in the color table for the bitplanes, allowing
separate colors for exterior and sprites.
To set the color palette, the user must simply write to the color
palette RAM. Addresses D100-D1FF (hex) program the 256 Red values,
addresses D200-D2FF (hex) program the 256 Green values, and addresses
D300-D3FF(hex) program the 256 Blue values. All 256 locations of both
the blue and green palettes are only 4 bits wide, so the upper four
data bits do nothing. Bit 4 of every red palette location is the FGBG
programming bit, the remaining 3 bits are not used. The palette
locations are not readable by the CPU.
2.4.5. Registers
C4567R6 Registers
MEMORY MAP SELECT AND ENABLE REGISTERS
--------------------------------------
(EN BIT MUST BE 1 FOR SELECT TO BE 0)
"4510" PORT
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | EN2 | EN1 | EN0 | 0000
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | CHREN | HIRAM | LORAM | 0001
+-------+-------+-------+-------+-------+-------+-------+-------+
VIC-II MODE REGISTERS
+-------+-------+-------+-------+-------+-------+-------+-------+ $D000+
| S0X7 | S0X6 | S0X5 | S0X4 | S0X3 | S0X2 | S0X1 | S0X0 | 00 SPRITE 0 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S0Y7 | S0Y6 | S0Y5 | S0Y4 | S0Y3 | S0Y2 | S0Y1 | S0Y0 | 01 SPRITE 0 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S1X7 | S1X6 | S1X5 | S1X4 | S1X3 | S1X2 | S1X1 | S1X0 | 02 SPRITE 1 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S1Y7 | S1Y6 | S1Y5 | S1Y4 | S1Y3 | S1Y2 | S1Y1 | S1Y0 | 03 SPRITE 1 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S2X7 | S2X6 | S2X5 | S2X4 | S2X3 | S2X2 | S2X1 | S2X0 | 04 SPRITE 2 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S2Y7 | S2Y6 | S2Y5 | S2Y4 | S2Y3 | S2Y2 | S2Y1 | S2Y0 | 05 SPRITE 2 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S3X7 | S3X6 | S3X5 | S3X4 | S3X3 | S3X2 | S3X1 | S3X0 | 06 SPRITE 3 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S3Y7 | S3Y6 | S3Y5 | S3Y4 | S3Y3 | S3Y2 | S3Y1 | S3Y0 | 07 SPRITE 3 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S4X7 | S4X6 | S4X5 | S4X4 | S4X3 | S4X2 | S4X1 | S4X0 | 08 SPRITE 4 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S4Y7 | S4Y6 | S4Y5 | S4Y4 | S4Y3 | S4Y2 | S4Y1 | S4Y0 | 09 SPRITE 4 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S5X7 | S5X6 | S5X5 | S5X4 | S5X3 | S5X2 | S5X1 | S5X0 | 0A SPRITE 5 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S5Y7 | S5Y6 | S5Y5 | S5Y4 | S5Y3 | S5Y2 | S5Y1 | S5Y0 | 0B SPRITE 5 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S6X7 | S6X6 | S6X5 | S6X4 | S6X3 | S6X2 | S6X1 | S6X0 | 0C SPRITE 6 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S6Y7 | S6Y6 | S6Y5 | S6Y4 | S6Y3 | S6Y2 | S6Y1 | S6Y0 | 0D SPRITE 6 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S7X7 | S7X6 | S7X5 | S7X4 | S7X3 | S7X2 | S7X1 | S7X0 | 0E SPRITE 7 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| S7Y7 | S7Y6 | S7Y5 | S7Y4 | S7Y3 | S7Y2 | S7Y1 | S7Y0 | 0F SPRITE 7 Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| S7X8 | S6X8 | S5X8 | S4X8 | S3X8 | S2X8 | S1X8 | S0X8 | 10 SPRITE 8 X
+-------+-------+-------+-------+-------+-------+-------+-------+
| RC8 | ECM | BMM | BLNK | RSEL | YSCL2 | YSCL1 | YSCL0 | 11 Y SCROLL
+-------+-------+-------+-------+-------+-------+-------+-------+
| RC7 | RC6 | RC5 | RC4 | RC3 | RC2 | RC1 | RC0 | 12 RASTER CNT
+-------+-------+-------+-------+-------+-------+-------+-------+
| LPX7 | LPX6 | LPX5 | LPX4 | LPX3 | LPX2 | LPX1 | LPX0 | 13 LITEPEN X
+-------+-------+-------+-------+-------+-------+-------+-------+
| LPY7 | LPY6 | LPY5 | LPY4 | LPY3 | LPY2 | LPY1 | LPY0 | 14 LITEPEN Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| SE7 | SE6 | SE5 | SE4 | SE3 | SE2 | SE1 | SE0 | 15 SPRITE ENA
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | RST | MCM | CSEL | XSCL2 | XSCL1 | XSCL0 | 16 X SCROLL
+-------+-------+-------+-------+-------+-------+-------+-------+
| SEXY7 | SEXY6 | SEXY5 | SEXY4 | SEXY3 | SEXY2 | SEXY1 | SEXYO | 17 SPR EXP Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| VS13 | VS12 | VS11 | VS10 | CB13 | CB12 | CB11 | | 18 VS/CB BASES
+-------+-------+-------+-------+-------+-------+-------+-------+
| IRQ | | | | LPIRQ | ISSC | ISBC | RIRQ | 19 INTERRUPTS
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | MLPI | MISSC | MISBC | MRIRQ | 1A INT MASKS
+-------+-------+-------+-------+-------+-------+-------+-------+
| BSP7 | BSP6 | BSP5 | BSP4 | BSP3 | BSP2 | BSP1 | BSP0 | 1B BK/SPR PRI
+-------+-------+-------+-------+-------+-------+-------+-------+
| SCM7 | SCM6 | SCM5 | SCM4 | SCM3 | SCM2 | SCM1 | SCM0 | 1C MC SPR
+-------+-------+-------+-------+-------+-------+-------+-------+
| SEXX7 | SEXX6 | SEXX5 | SEXX4 | SEXX3 | SEXX2 | SEXX1 | SEXX0 | 1D SPR EXP X
+-------+-------+-------+-------+-------+-------+-------+-------+
| SSC7 | SSC6 | SSC5 | SSC4 | SSC3 | SSC2 | SSC1 | SSC0 | 1E SPR-SPR COL
+-------+-------+-------+-------+-------+-------+-------+-------+
| SBC7 | SBC6 | SBC5 | SBC4 | SBC3 | SBC2 | SBC1 | SBC0 | 1F SPR-BK COL
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | BORD3 | BORD2 | BORD1 | BORD0 | 20 EXT COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | BK0C3 | BK0C2 | BK0C1 | BK0C0 | 21 BK0 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | BK1C3 | BK1C2 | BK1C1 | B10C0 | 22 BK1 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | BK2C3 | BK2C2 | BK2C1 | BK2C0 | 23 BK2 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | BK3C3 | BK3C2 | BK3C1 | BK3C0 | 24 BK3 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | SM0C3 | SM0C2 | SM0C1 | SM0C0 | 25 SPR MC0
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | SM1C3 | SM1C2 | SM1C1 | SM1C0 | 26 SPR MC1
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S0C3 | S0C2 | S0C1 | S0C0 | 27 SPR0 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S1C3 | S1C2 | S1C1 | S1C0 | 28 SPR1 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S2C3 | S2C2 | S2C1 | S2C0 | 29 SPR2 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S3C3 | S3C2 | S3C1 | S3C0 | 2A SPR3 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S4C3 | S4C2 | S4C1 | S4C0 | 2B SPR4 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S5C3 | S5C2 | S5C1 | S5C0 | 2C SPR5 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S6C3 | S6C2 | S6C1 | S6C0 | 2D SPR6 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | S7C3 | S7C2 | S7C1 | S7C0 | 2E SPR7 COLOR
+-------+-------+-------+-------+-------+-------+-------+-------+
VIC-III MODE REGISTERS
+-------+-------+-------+-------+-------+-------+-------+-------+ D000+
| KEY7 | KEY6 | KEY5 | KEY4 | KEY3 | KEY2 | KEY1 | KEY0 | 2F KEY
+-------+-------+-------+-------+-------+-------+-------+-------+
| ROM | CROM | ROM | ROM | ROM | PAL | EXT | CRAM | 30 CONTROL A
| @E000 | @9000 | @C000 | @A000 | @8000 | | SYNC | @DC00 |
+-------+-------+-------+-------+-------+-------+-------+-------+
| H640 | FAST | ATTR | BPM | V400 | H1280 | MONO | INT | 31 CONTROL B
+-------+-------+-------+-------+-------+-------+-------+-------+
| BP7EN | BP6EN | BP5EN | BP4EN | BP3EN | BP2EN | BP1EN | BP0EN | 32 BP ENABS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B0AD15 |B0AD14 |B0AD13 | |B0AD15 |B0AD14 |B0AD13 | | 33 BITPLANE 0
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B1AD15 |B1AD14 |B1AD13 | |B1AD15 |B1AD14 |B1AD13 | | 34 BITPLANE 1
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B2AD15 |B2AD14 |B2AD13 | |B2AD15 |B2AD14 |B2AD13 | | 35 BITPLANE 2
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B3AD15 |B3AD14 |B3AD13 | |B3AD15 |B3AD14 |B3AD13 | | 36 BITPLANE 3
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B4AD15 |B4AD14 |B4AD13 | |B4AD15 |B4AD14 |B4AD13 | | 37 BITPLANE 4
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B5AD15 |B5AD14 |B5AD13 | |B5AD15 |B5AD14 |B5AD13 | | 38 BITPLANE 5
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B6AD15 |B6AD14 |B6AD13 | |B6AD15 |B6AD14 |B6AD13 | | 39 BITPLANE 6
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|B7AD15 |B7AD14 |B7AD13 | |B7AD15 |B7AD14 |B7AD13 | | 3A BITPLANE 7
| ODD | ODD | ODD | | EVEN | EVEN | EVEN | | ADDRESS
+-------+-------+-------+-------+-------+-------+-------+-------+
|BP7COMP|BP6COMP|BP5COMP|BP4COMP|BP3COMP|BP2COMP|BP1COMP|BP0COMP| 3B BP COMPS
+-------+-------+-------+-------+-------+-------+-------+-------+
| BPY8 | BPX6 | BPX5 | BPX4 | BPX3 | BPX2 | BPX1 | BPX0 | 3C BITPLANE X
+-------+-------+-------+-------+-------+-------+-------+-------+
| BPY7 | BPY6 | BPY5 | BPY4 | BPY3 | BPY2 | BPY1 | BPY0 | 3D BITPLANE Y
+-------+-------+-------+-------+-------+-------+-------+-------+
| HPOS7 | HPOS6 | HPOS5 | HPOS4 | HPOS3 | HPOS2 | HPOS1 | HPOS0 | 3E HORIZ POS
+-------+-------+-------+-------+-------+-------+-------+-------+
| VPOS7 | VPOS6 | VPOS5 | VPOS4 | VPOS3 | VPOS2 | VPOS1 | VPOS0 | 3F VERT POS
+-------+-------+-------+-------+-------+-------+-------+-------+
DAT MEMORY PORTS
+-------+-------+-------+-------+-------+-------+-------+-------+ D000+
|B0PIX7 |B0PIX6 |B0PIX5 |B0PIX4 |B0PIX3 |B0PIX2 |B0PIX1 |B0PIX0 | 40 BITPLANE 0
+-------+-------+-------+-------+-------+-------+-------+-------+
|B1PIX7 |B1PIX6 |B1PIX5 |B1PIX4 |B1PIX3 |B1PIX2 |B1PIX1 |B1PIX0 | 41 BITPLANE 1
+-------+-------+-------+-------+-------+-------+-------+-------+
|B2PIX7 |B2PIX6 |B2PIX5 |B2PIX4 |B2PIX3 |B2PIX2 |B2PIX1 |B2PIX0 | 42 BITPLANE 2
+-------+-------+-------+-------+-------+-------+-------+-------+
|B3PIX7 |B3PIX6 |B3PIX5 |B3PIX4 |B3PIX3 |B3PIX2 |B3PIX1 |B3PIX0 | 43 BITPLANE 3
+-------+-------+-------+-------+-------+-------+-------+-------+
|B4PIX7 |B4PIX6 |B4PIX5 |B4PIX4 |B4PIX3 |B4PIX2 |B4PIX1 |B4PIX0 | 44 BITPLANE 4
+-------+-------+-------+-------+-------+-------+-------+-------+
|B5PIX7 |B5PIX6 |B5PIX5 |B5PIX4 |B5PIX3 |B5PIX2 |B5PIX1 |B5PIX0 | 45 BITPLANE 5
+-------+-------+-------+-------+-------+-------+-------+-------+
|B6PIX7 |B6PIX6 |B6PIX5 |B6PIX4 |B6PIX3 |B6PIX2 |B6PIX1 |B6PIX0 | 46 BITPLANE 6
+-------+-------+-------+-------+-------+-------+-------+-------+
|B7PIX7 |B7PIX6 |B7PIX5 |B7PIX4 |B7PIX3 |B7PIX2 |B7PIX1 |B7PIX0 | 47 BITPLANE 7
+-------+-------+-------+-------+-------+-------+-------+-------+
COLOR PALETTES
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | FG/BG | RED3 | RED2 | RED1 | RED0 | D100-D1FF RED
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | GRN3 | GRN2 | GRN1 | GRN0 | D200-D2FF GREEN
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | BLU3 | BLU2 | BLU1 | BLU0 | D300-D3FF BLUE
+-------+-------+-------+-------+-------+-------+-------+-------+
COLOR/ATTRIBUTE RAM
+-------+-------+-------+-------+-------+-------+-------+-------+
| UNDER | HILIT | REVRS | BLINK | INDX3 | INDX2 | INDX1 | INDX0 | D800-DBFF
+-------+-------+-------+-------+-------+-------+-------+-------+ (DC00-DFFF)
VIDEO BANK SELECT AND ENABLE
(EN BIT MUST BE 1 FOR VB TO BE 0)
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | VB1 | VB0 | DD00 (WRITE)
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | EN1 | EN0 | DD02 (WRITE)
+-------+-------+-------+-------+-------+-------+-------+-------+
2.4.6. Limitations and Avoiding Them
Limitations of the C4567R6 and How to Avoid Them
Watch carefully, when particular mode Changes take effect. You
may change PAL, H1280, V400, BPM, ATTR, and H640 modes anytime.
However, the new mode selection will not take effect until after the
last line of the current character row. This is intended to simplify
split-screen programming. But, if you are using the DAT to access
bitmaps or bitplanes, you must wait long enough after selecting a new
H640 or V400 mode to guarantee that the C4567R6 is in the mode you
intended before doing, any DAT accesses. The DAT uses these bits to
determine how to draw the image.
If you want to use all four 640x400 bitplanes, you will be
limited to a maximum of 5 sprites having unique data. You can have
more sprites, if they are permitted to share data. This limitation is
due to the fact that sprite pointers and data must be fetched from the
16K video matrix which must also be shared with one of the bitplanes.
The bitplane will use 16000 of the 16384 bytes. This leaves 384 bytes,
which would support 6 sprite data blocks of 64 bytes, each. But the
sprite pointers must come out of the highest addressed block, thus
leaving only 5 sprite data blocks available.
If you really need 8 unique sprites, you can use four 640x384
pixel bitplanes. This is done by setting the row select bit to 24 row
mode. This will give you a total of 16 blocks of 64. This is more than
enough, so you can even have alternate sprite data blocks.
Note that Sprites and Sprite coordinates are unaffected by screen
resolution, meaning that in 640x400 screens, for example, the sprites
are still the same size on the screen and are still positioned as if
the display map were 320x200. In an 80-column text, or 640-wide
bitplane, screen a "dot" on a sprite will cover 2 pixels.
Note also that, in bitplane, mode, sprites will only collide with
"background" data which has bits "on" in bitplane 2. All other
bitplanes will NOT cause a sprite-to-background-data collision.
An Example of How to Program the Color Palette
for 1280 Pixel Resolution and Driving FGBG
In 1280 mode you must use 2 bitplanes to time-multiplex into 1.
So, for example, lets use BP0 for "early" bytes and BP1 for "late"
bytes.
+-----+-----+-----+-----+-----+-----+-----+-----+
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | early BP0
+-----+-----+-----+-----+-----+-----+-----+-----+
+-----+-----+-----+-----+-----+-----+-----+-----+
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | early BP1
+-----+-----+-----+-----+-----+-----+-----+-----+
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|7E|7L|6E|6L|5E|5L|4E|4L|3E|3L|2E|2L|1E|1L|0E|0L| final output
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
The early pixels will be interleaved with the late ones, as shown. So,
if you want to alter 1 pixel, you must decide which bitplane it will
be in, and operate on its byte.
Make sure the H1280 control bit is set. If it is, BP7 will be
forced low for an early pixel, and high for a late pixel. Let's
program the palette to multiplex BP0 early and BP1 late and ignore BP2
and BP3. I want my background to be black, and image to be white, and,
at the same time have BP3 drive a 640 pixel monochrome screen with the
FGBG pin. (it too could be 1280 pixels).
Display Address Translator (DAT)
The C4567R6 contains a special piece of hardware, known as the
Display Address Translator, or DAT, which allows the programmer to
access the bitplanes directly. In the old VIC configuration, the
bitmap was organized as 25 rows of 40 stacks of 8 sequential bytes.
This is great for displaying 8 x 8 characters, but difficult for
displaying graphics.
The DAT overcomes the original burden by allowing the programmer
to specify the (X,Y) location of the byte of bitplane memory to be
read, modified, or written. This is done by writing the (X,Y)
coordinates to the BPX and BPY register, respectively. The user can
then read, modify, or write the specified location by reading,
modifying, or writing one of the eight Bitplane registers. There is
one bitplane register for each bitplane.
The DAT automatically determines whether to use 320 or 640 pixel
mode, and whether to use 200 or 400 line mode. It will also use the
areas specified for the bitplanes, using the Bitplane Address
registers.
Horizontal and Vertical Positioning
The C4567R6 has two registers to allow the programmer to alter
the positioning of the display relative to the borders of his CRT
(television or monitor). Initially the positioning registers are set
to zero, to give C64 standard positioning. These registers are signed,
two's complement values which specify an offset from the default
positions.
Chroma Killer
The C4567R6 provides analog RGB video, with sync on all colors,
an analog luminance output, with sync, and an analog NTSC (or PAL on
PAL versions) chrominance output. It also provides a separate digital
video signal, and a separate digital sync. When using the C4567R6 with
a black and white television receiver, it may be best to suppress the
chrominance information. This can be done by setting the MONO bit in
control register "B".
Additional ROM
The C4567R6 does all decoding for ROMs. It supports a total of
32K of ROM, which is 12K over what the C64 is configured for. This 12K
of extra ROM is available in one 8K block at 8000 (hex), and one 4K
block at C000 (hex). To enable ROM at these areas, set the ROM@8000 or
ROM@COOO bits in Control Register "A". (Note that there are other
chips in the C65 which extend this addressing limitation. The C65 has
a 1MBit/128kByte ROM built-in.)
Alternate Character Set
Ordinarily, the C4567R6 will always fetch ROM-based character
data from addresses D000-DFFF. If the CROM@9000 bit is set in control
register "A", ROM-based character data will be fetched from addresses
9000-9FFF. This allows for an alternate ROM-based character set.
Future Document Topics
At a later time, this document may also describe the following
C4567R6 enhancements and features...
Weatherfax Mode
Multiple (2-8) playfields
Playfield prioritization
Multiple CRT configurations using the digital and analog video
Multiple sub-palettes
Mixing 1280 pixel and 640 pixel bitplanes
Using all 272 palette locations
Transparency, highlighting, and palette logic functions
Use of the priority/collision bitplane with the sprites
Use of external Video RAM
palette palette
addresses outputs
--------- -------------------------
F
BBBBBBBB G
PPPPPPPP RRRR GGGG BBBB B
76543210 3210 3210 3210 G
-------- ---- ---- ---- -
00000000 0000 0000 0000 0 Since BP7 is low,
00000001 1111 1111 1111 0 the early pixel matters.
00000010 0000 0000 0000 0 Only care about BP0 data,
00000011 1111 1111 1111 0 since it supplies the
00000100 0000 0000 0000 1 early data. Notice how
00000101 1111 1111 1111 1 the RGB output is all 1's
00000110 0000 0000 0000 1 only when BP0 is a 1,
00000111 1111 1111 1111 1 regardless of what the
00001000 0000 0000 0000 0 other BP's are doing.
00001001 1111 1111 1111 0 This is how you program
00001010 0000 0000 0000 0 the palette to ignore
00001011 1111 1111 1111 0 certain bitplanes.
00001100 0000 0000 0000 1
00001101 1111 1111 1111 1 Did you see how FGBG is
00001110 0000 0000 0000 1 a 1 only when BP3 is a 1
00001111 1111 1111 1111 1 regardless of other BPs?
10000000 0000 0000 0000 0 Now BP7 is high. The late
10000001 0000 0000 0000 0 pixels are being output.
10000010 1111 1111 1111 0 Now, the RGB output is all
10000011 1111 1111 1111 0 1's only when BP1 (the
10000100 0000 0000 0000 1 late BP) is a 1, regardless
10000101 0000 0000 0000 1 of what the other BPs are
10000110 1111 1111 1111 1 doing. This is how to time
10000111 1111 1111 1111 1 multiplex between planes.
10001000 0000 0000 0000 0
10001001 0000 0000 0000 0 Notice, now, that FGBG is
10001010 1111 1111 1111 0 still a 1 only if BP3 is
10001011 1111 1111 1111 0 a 1, regardless of the
10001100 0000 0000 0000 1 other BPs, like before.
10001101 0000 0000 0000 1 This makes FGBG immune to
10001110 1111 1111 1111 1 the mutiplexing. It also
10001111 1111 1111 1111 1 shows how you can mix
modes on the same screen!
Note that BP4, BP5, and BP6 will be zero unless I specifically ask
them to be set to 1 in the Bitplane Complement register. So if they
are zero, I do not need to program the rest of the palette. But I
can program the other parts of the palette, and use the bitplane
complements for BP4, BP5, and BP6 to switch between sub-palettes!
VIC-II modes, enhanced VIC-II modes, and VIC-III modes.
The VIC-III supports, what are called, "VIC-II" video modes. It
also supports enhancements to the basic VIC-II modes. There are, also
a variety of all-new VIC-III modes. In order to utilize any enhanced
VIC-II mode, or any VIC-III mode, a special keying sequence is
required.
VIC-II modes
Standard Character Mode
Multi-Color Character Mode
Extended Color Mode
Bit Map Mode
Sprites
Enhancements available to VIC-II modes
80 column character modes (vs standard 40 columns)
640 x 200 pixel bit maps (vs standard 320 x 200)
Programmable colors
Character attributes -- Underline, Blink, Reverse, Hilight
Alternate character set
Interlace
VIC-III video modes
Bitplane modes
1280 pixel ultra-high resolution
400 line operation
Location of VIC-II video data in memory (Video Bank selection)
The VIC-II modes can only access a maximum of 16K bytes of
memory, out of a total of 64K of potentially available display memory.
To select which fourth of the 64K memory will be available for VIC-II
video accesses, the user must specify which Video Bank to use. This is
done by setting bits 0 and 1 in the Bank Select register (location
DD02 hex) as shown.
Bit Video Address
1 0 Bank Range
- - ---- -------
0 0 3 C000-FFFF
0 1 2 8000-BFFF
1 0 1 4000-7FFF
1 1 0 0-3FFF
The same two bits must be set to a 1 in an enable register (location
DD00 hex) in order for a 0 data bit to be recognized. Both of these
registers, though write only, may have bits shared, elsewhere in the
application system. If this is the case, care must be taken to
preserve the other port bits not shown, here.
The Video Matrix
The Video Matrix is a block of memory used to store
character-organized display data. Depending on whether the chip is in
40 column or 80 column display mode, it is 1024 or 2048 bytes long.
Since the VIC-II modes can only access 16K bytes of memory, this means
there are "16 or 8 places that the video matrix can appear within the
16K Video Bank, depending on whether 40 or 80 column mode is selected.
The location of the Video matrix is chosen by bits 4 through 7 of the
Memory Pointers register (address D018 hex). Bit 4 has no effect in 80
column mode.
The Character Memory Block
The Character Memory is a 2048 byte block of memory that contains
character image data. Each character definition requires 8 bytes in
order to display a 8 x 8 bit character image. And there are 256
possible values for each character code, so 8 x 256, or 2048 locations
are required. For each character definition stored in the character
memory, the lowest of the eight memory addresses used by the character
represents the top one of eight scan lines of the character. The
leftmost pixel of each character is the most significant bit (bit 7)
of the respective character memory byte.
Since the VIC-II modes can only access 16K bytes of memory, there
are only eight choices where the Character Memory Block can be
located. That location is selected by bits 1-3 of the Memory Pointers
register (address D018 hex). Special combinations of Character Memory
Block and Video Bank selections determine whether the character image
data is fetched from RAM or from ROM, as shown below.
CB bit VB bit Image hex
3 2 1 1 0 source address
- - - - - ------ -------
0 0 0 x x RAM (0-7FF)+VB
0 0 1 x x RAM (800-FFF)+VB
0 1 0 x 0 ROM D000-D7FF (C000-C7FF if CROM@C000)
0 1 0 x 1 RAM (1000-17FF)+VB
0 1 1 x 0 ROM D000-D7FF (C000-C7FF if CROM@C000)
0 1 1 x 1 RAM (1800-1FFF)+VB
1 0 0 x x RAM (2000-27FF)+VB
1 0 1 x x RAM (2800-2FFF)+VB
1 1 0 x x RAM (3000-37FF)+VB
1 1 1 x x RAM (3800-3FFF)+VB
Color/Attribute Memory
The VIC-II modes have a 1024 or 2048 byte color and attribute
memory, depending on whether 40 columns or 80 columns are selected.
This memory is used to determine what color and what attributes are to
be applied to each character in the video matrix. Color/Attribute RAM
is immovable. Physically, it is located at RAM locations 1F800-1FFFF.
The CPU, however can access the 1024 byte portion at addresses
D800-DBFF. It can access the entire 2048 byte block from D800-DFFF if
the COL@DCOO bit is set in control register A. The CPU can also access
Color/Attribute RAM directly at addresses 1F800- 1FFFF.
Standard Character Mode
Standard Character Mode is selected by writing 0 to the ECM and
BMM bits in Mode Register A (location D011 hex), writing 0 to the MCM
bit in Mode Register B (location D016 hex), and by writing 0 to
Control Register B (location D031 hex).
2.5. CSG F011x -- C65 Disk Controller Chip gate array (preliminary)
2.5.1. Description
CSG4171-F011 Revision C
The CSG4171-F011 is a low cost MFM disk interface. It requires
the use of an external 512 byte RAM as a data cache buffer. This
interface can perform reads from and writes to MFM formatted
diskettes, as well as free-format full track reads and writes. It can
also format diskettes. Logic is also provided for timed head stepping
and for motor spin-up. The F011 provides for expansion drive
interconnect using a serial protocol for control and status signals.
It also incorporates an index pulse simulator for drives that do not
have an index sensor.
Unlike its predecessors, the "C" revision provides:
a. Active high local LED output.
b. Correct remote DSKCHG status.
c. Protection of control bits when changing drive selects.
d. IRQ cleared on reset.
e. Blinking of the local LED.
f. Swapping of buffer halves for CPU access.
g. Two new Digital Phase Locked Loop (DPLL) read recovery methods
in addition to the original Full Correction (FC) algorithm.
h. Improved capture range in Full Correction.
i. Decoding for external disk registers.
j. A one line to two line active low decoder for external hardware.
Read recovery options
The F011 now provides 3 methods for recovering MFM formatted disk
data. Each method has its own advantages and tradeoffs. This is how
they work...
The read-recovery, or dibit counter divides the dibit period into
sixteen partitions or counts assuming no read data pulses occur or
correctly positioned read pulses occur. When a read data pulse with
less-than-ideal positioning occurs, the dibit counter will modify its
count depending on whether Full Correction (FC), Digital Phase Locked
Loop (DPLL) or Alternate Phase Locked Loop (ALT) recovery methods are
selected.
|---- DIBIT CELL ----|
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
| | | |0|1|2|3|4|5|6|7|8|9|A|B|C|D|E|F| | | |DIBIT COUNTER
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
---------------+ +-----------------------------
| | READ DATA PULSE
+-+
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
| | | | | | | | |8|9|A|B|C|D|E|F| | | | | | |NEW (FC) DIBIT COUNTER
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
NEW DIBIT CELL ------|
In Full Correction (FC) the dibit counter is forced to count
eight after a read pulse is received. This is the equivalent of
forcing the read pulse to the center of the bit cell. This method
fully compensates for phase and frequency variation. It will tolerate
a considerable range of bit frequency error at the cost of permitting
a limited range of bit phase error.
---------------+ +-----------------------------
| | READ DATA PULSE
+-+
|---- DIBIT CELL ----|
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
| | | |0|1|2|3|4|5|6|7|8|9|A|B|C|D|E|F| | | |DPLL RESULT
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
|--- ADD 1 ---| |---- SUB 1 ----|
In Digital Phase Locked Loop (DPLL) recovery, the dibit counter
is incremented if a read pulse occurs early (before a dibit cell
center), decremented if a read pulse is late (after a dibit cell
center), or counts normally if no read pulse occurs, or if a pulse
occurs within a dibit cell center. This method has the ability to
track a large range of bit phase error, but, unfortunately can only
handle a very narrow frequency error range.
---------------+ +-----------------------------
| | READ DATA PULSE
+-+
|---- DIBIT CELL ----|
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
| | | |0|1|2|3|4|5|6|7|8|9|A|B|C|D|E|F| | | |ALT DPLL RESULT
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
|- +2 --| +1 -| |- -1 --|- -2 --|
In Alternate Digital Phase Locked Loop (ALT) recovery, the dibit
counter behaves exactly as it does in standard DPLL mode, except that
if a read pulse occurs more than 3 counts early, or 4 counts late, the
counter is incremented or decremented by 2. Like DPLL, this method can
tolerate a large range of bit phase error, but can also compensate for
a larger frequency error range.
2.5.2. Configuration
2.5.2.1. Pinout
Pin Name Active Dir Type Description
--- ----- ------ --- ---- -----------
1 RD low input disk read-data
2 MOT low output disk motor on
3 SIDE low output disk side select
4 WPROT low input disk write protect
5 TK0 low input disk track 0
6 WGATE low output disk write gate
7 RW input cpu read/write
8 WD low output disk write data
9 A0 input cpu address
10 A1 input cpu address
11 A2 input cpu address
12 A3 input cpu address
13 INDEX low input disk index
14 GND
15 D0 I/O cpu data
16 D1 I/O cpu data
17 D2 I/O cpu data
18 D3 I/O cpu data
19 D4 I/O cpu data
20 D5 I/O cpu data
21 D6 I/O cpu data
22 D7 I/O cpu data
23 IRQ low out oc cpu interrupt request
24 VCC
25 VCC
26 RA8 output ram address
27 RA7 output ram address
28 RA6 output ram address
29 RA5 output ram address
30 RA4 output ram address
31 RA3 output ram address
32 RA2 output ram address
33 RA1 output ram address
34 RA0 output ram address
35 CS low input cpu chip select
36 RRW output ram read/write
37 RCS low output ram chip select
38 RD7 I/O ram data
39 RD6 I/O ram data
40 RD5 I/O ram data
41 RD4 I/O ram data
42 RD3 I/O ram data
43 RD2 I/O ram data
44 RD1 I/O ram data
45 RD0 I/O ram data
46 SERIO low I/O exp serial control/status
47 LD low output exp direction of serio
48 CLK low output exp shift clock
49 LOCAL low input disk local drive available
50 TSTCLK input test test clock
51 EXTREG low output to external registers
52 A4 input cpu address
53 DRO low output disk drive select 0
54 CS1 low input cpu chip select external logic
55 LED high output disk panel LED
56 DIR output disk stepping direction
57 STEP low output disk stepping command
58 PH0 input cpu clock
59 DSKIN low input disk disk inserted
60 RES low input cpu reset
61 XTAL1 input crystal
62 XTAL2 output crystal
63 VENDOR low input vendor
64 VCC
65 CSLO low output to external logic
66 CSHI low output to external logic
67 GND
68 GND
2.5.2.2. Signal Descriptions
Processor Interface Lines
A0-A4 These five address inputs select which internal or external
register is to be read or written by the processor.
RW The RW input determines whether a register will be written
(RW=low) or read (RW=high) by the processor.
D0-D7 Eight bi-directional lines which transfer data to and from
the processor during register reads and writes. These are
normally inputs, but become driven outputs when CS and PH0
are true.
CS The Chip Select is a low-true input that determines that a
register read or write will occur when PH0 becomes true.
CS1 External hardware chip select input. This low-true signal,
when asserted, will cause CSLO to go true (low) if A4 is low,
or CSHI to go true (low) if A4 is high.
PH0 A high-true input that must be driven high by the processor
to indicate that A0-A4, RW, and CS are valid.
IRQ The Interrupt Request is an open-drain output that will sink
current when an interrupt is requested by the F011. IRQ will
go low (true) when the BUSY status bit changes from true to
false if IRQ is enabled.
RES The Reset is a low-true input used to reset internal events.
When RES goes low (true) any command in progress will be
terminated. RES will not, however, affect any control
register bits.
Buffer RAM Interface Lines
RA0-RA8 These nine RAM Address outputs must be connected directly to
nine of the external buffer RAM chip address inputs. These
may be scrambled for PCB simplification.
RD0-RD7 These eight bi-directional lines must be connected to the
eight bi-directional data lines of the external buffer RAM.
These may be scrambled for PCB simplification. RDO-RD7 are
inputs except when RRW and PCS are low. Then they become
driven outputs.
RRW The RAM Read/Write output must be connected to the R/W input
of the external buffer RAM to control reading and writing.
RCS The RAM Chip Select is a 1.0 Mhz clock of 50% duty cycle, and
is low at a time when RA0-RA8, RRW, and RCS are valid. It
must be connected to the CS input of the external buffer RAM.
Disk Drive Interface Lines
(All disk signals are low-true)
RD The Read Data input expects a series of low-going pulses
from the currently selected disk drive.
WD The Write Data output provides a series of low-going pulses
at all times to all drives. It represents the MFM encoded
data stream used for disk writes.
WGATE The Write Gate output, when true, causes the Write Data to
be written to the diskette in the currently selected drive.
WPROT The Write Protect input must indicate, when true, that the
present diskette in the local drive must not be written to.
The F011 will not assert WGATE if WPROT is true, and will not
execute any write related commands.
LOCAL The Local Drive Available input must be grouded in systems
that have a resident local drive 0, and must be tied to Vcc
in systems that are diskless. This will permit drive 0 to be
configured externally.
DR0 This output, when low, indicates that the local drive
(Drive 0) is the currently selected drive.
DISKIN The Disk In Input must indicate when a diskette is physically
in the local drive, and the drive is available for use.
MOT The Motor On output, when true, turns on the motor of the
local disk drive only. (Also turns on local LED).
LED The LED output, when true turns on the panel Light-emitting-
diode of the local disk drive only. (Causes LED to BLINK).
SIDE The Side select output determines which side of the media
is to be read or written. It is high (false) for side 0, and
low (true) for side 1. This output reflects the status of the
SIDE control bit regardless of which drive is selected.
STEP The Step output provides a low-going pulse when a head
stepping command is executed, regardless of which drive is
selected.
DIR The Direction output indicates to the drives whether the
read/write head is to step toward track 0 (DIR=high) or away
from track 0 (DIR=low) when a step pulse is received. This
output reflects the status of the DIR command register bit
regardless of which drive is selected.
TK0 The Track Zero input must determine when the read/write head
of the local drive is positioned over track zero. This input
will not suppress stepping pulses.
INDEX The Index pulse input must provide a low going pulse for each
spindle rotation of the local drive, if the local drive has
an index sensor. This input must be tied low if the local
drive has no index sensor.
Expansion Drive Interface Lines
(all expansion lines are low-true)
SERIO The Serial I/O line is a bi-directional signal that is used
to pass control to all external disk drives, and to receive
status information from them. It is a driven, output when LD
is high, and an input, otherwise.
LD The Load Data output tells the external expansion drives
when to update control information shifted off of the serio
line, when to load status information for shifting, and when
to drive the SERIO line. (This is discussed later.)
CLK The Clock output provides a 50% duty cycle clock at 250Khz
to be used by the external expansion drives for shifting
control and status information in and out.
Other Signals
XTAL1 These two lines form two poles of a series-resonant crystal
XTAL2 oscillator circuit. XTAL1 is an input, and XTAL2 is an
output. An 8.0000Mhz crystal should be used.
VENDOR The software Vendor identifier input determines whether the
F011 will be capable of generating protect marks within the
the sector headers. Production units will not have this
signal bonded, except those shipped to software vendors. This
pin should be grounded at all times.
TSTCLK The Test Clock input is used to reduce F011 test times. This
pin should be grounded at all times.
CSLO External hardware active-low chip select output. Goes low
when CS1 and A4 are both low.
CSHI External hardware active-low chip select output. Goes low
when CS1 is low and A4 is high.
EXTREG External register active-low chip select output. Goes low
when CS is low and A4 is high.
2.5.3. Registers
C4171-F011C Registers
7 6 5 4 3 2 1 0
+-------+-------+-------+-------+-------+-------+-------+-------+
CONTROL | IRQ | LED | MOTOR | SWAP | SIDE | DS2 | DS1 | DS0 | 0 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
COMMAND | WRITE | READ | FREE | STEP | DIR | ALGO | ALT | NOBUF | 1 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
STAT A | BUSY | DRQ | EQ | RNF | CRC | LOST | PROT | TKQ | 2 R
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
STAT B | RDREQ | WTREQ | RUN | NGATE | DSKIN | INDEX | IRQ | DSKCHG| 3 R
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
TRACK | T7 | T6 | T5 | T4 | T3 | T2 | T1 | T0 | 4 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
SECTOR | S7 | S6 | S5 | S4 | S3 | S2 | S1 | S0 | 5 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
SIDE | S7 | S6 | S5 | S4 | S3 | S2 | S1 | S0 | 6 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
DATA | D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 | 7 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
CLOCK | C7 | C6 | C5 | C4 | C3 | C2 | C1 | C0 | 8 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
STEP | S7 | S6 | S5 | S4 | S3 | S2 | S1 | S0 | 9 RW
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
P CODE | P7 | P6 | P5 | P4 | P3 | P2 | P1 | P0 | A R
+-------+-------+-------+-------+-------+-------+-------+-------+
Control Register
Data from the control register is sent to both the local drive
(DR0) and all of the serially connected expansion drives (DR1-DR7).
The MOTOR and LED signals will be held for the local drive while other
drives are selected.
IRQ When set, enables interrupts to occur, when reset clears and
disables interrupts.
LED These two bits control the state of the MOTOR and LED
MOTOR outputs. When both are clear, both MOTOR and LED outputs will
be off. When MOTOR is set, both MOTOR and LED Outputs will be
on. When LED is set, the LED will "blink".
SWAP swaps upper and lower halves of the data buffer
as seen by the CPU.
SIDE when set, sets the SIDE output to 0, otherwise 1.
DS2-DS0 these three bits select a drive (drive 0 thru drive 7). When
DS0-DS2 are low and the LOCAL input is true (low) the DR0
output will go true (low).
Command Register
WRITE must be set to perform write operations.
READ must be set for all read operations.
FREE allows free-format read or write vs formatted
STEP write to 1 to cause a head stepping pulse.
DIR sets head stepping direction
ALGO selects read and write algorithm. 0=FC read, 1=DPLL read,
0=normal write, 1=precompensated write.
ALT selects alternate DPLL read recovery method. The ALG0 bit
must be set for ALT to work.
NOBUF clears the buffer read/write pointers
Status Registers
The appropriate status bits are sampled from the local status
inputs if the local drive (DR0) is selected. Otherwise, those bits are
sampled from the serially connected expansion drive (DR1-DR7).
BUSY command is being executed
DRQ disk interface has transferred a byte
EQ buffer CPU/Disk pointers are equal
RNF sector not found during formatted write or read
CRC CRC check failed
LOST data was lost during transfer
PROT disk is write protected
TK0 head is positioned over track zero
RDREQ sector found during formatted read
WTREQ sector found during formatted write
RUN indicates successive matches during find operation
WGATE write gate is on
DSKIN indicates that a disk is inserted in the drive
INDEX disk index is currently over sensor
IRQ an interrupt has occurred
DSKCHG the DSKIN line has changed
this is cleared by deselecting drive
Track Register
Sector Register
Side Register
The Track, Side and Sector registers are used in FIND operations
to locate a given sector on a given track on a given side.
Data Register
The data register is the CPU gateway to the data buffer for both
read and write operations.
Clock Register
The clock register is used to define the clock pattern to be used
to write address and data marks. This register should normally be
written to FF (hex).
Step Register
The step register is used to time head stepping. This register is
compared to a counter, which is clocked at 16Khz, giving a time of
62.5 microseconds per count, allowing a maximum of 16 milliseconds of
step time per step operation.
Protect Code Register
The Protection Code register is a read-only register that
contains the protect code of the last sector read. If the last sector
read does not contain a Protect Mark in its header, then this register
will contain zero.
Legal commands are...
hexcode notes macro function
------- ----- ----- --------
40 1,4,5 RDS Read Sector
80 1,2 WTS Write Sector
60 1,4,5 RDT Read Track
A0 1,2 WTT Write Track (format)
10 3 STOUT Head Step Out
14 3 TIME Time 1 head step interval (no pulse)
18 3 STIN Head Step In
20 3 SPIN Wait for motor spin-up
00 3 CAN Cancel any command in progress
01 CLB Clear the buffer pointers
Notes: 1. Add 1 for nonbuffered operation
2. Add 4 for write precompensation
3. Add 1 to clear buffer pointers
4. Add 4 for DPLL recovery instead of FC recovery
5. Add 6 for Alternate DPLL recovery
2.5.4. Command Descriptions
Execution of any legal command will cause the BUSY status to be
set, and the IRQ, RNF, CRC, and LOST flags to be cleared. Execution of
the CANcel or CLearBuffer commands, or any write operation command
with, the WPROT status set, or any illegal command, will not cause a
normal BUSY condition. However, any write to either the Command
Register or the Control register will automatically cause BUSY to be
set for at least one round trip delay of transmission and reception of
the serialized control and status signals. When BUSY gets reset,
either by successful command completion, error termination, round trip
completion, or by user cancellation, the IRQ flag will be set, and an
interrupt generated, unless interrupts are disabled.
The user may CANcel any operation in progress at any time using
the CAN command to can it. Use of this command during write operations
is not advised.
Unbuffered operations
If the buffer pointers are held clear by setting bit 0 in the
command register while issuing a command, unbuffered operations will
result. These are most useful for formatting a diskette. The DRQ flag
in status register A indicates when a transfer has occurred to or from
the disk.
For read operations, DRQ set, indicates that a byte of data has
been read from disk, and must be read by the CPU. Reading the data
with the CPU will clear the DRQ flag. If the data is not read by the
time another byte is read from the disk, the old data will be
overwritten and the LOST status flag will be set. The LOST flag will
remain set until the next command is written.
For write operations, the user should supply the first byte of
data either before, or shortly after issuing a write command. The DRQ
flag set indicates that the byte has been written to disk, and the CPU
must supply the next byte. When the CPU supplies a byte the DRQ flag
will be cleared. If the CPU does not supply a new byte in the time
that it is required by the disk interface, the previous byte data will
be written, and the LOST flag will be set. The LOST flag will remain
set until the next command is written.
Buffered operations
Buffered operations can be monitored by reading status register
A. The DRQ and EQ bits indicate the immediate status of the buffer
pointers. During any operation, the EQ bit, when set, indicates that
both the disk and CPU buffer pointers are pointing to the same
location. This can mean that the buffer is full or empty, depending on
what operation is, or will be performed. The DRQ bit set indicates
that the disk was last to access the buffer, and clear indicates that
CPU was last to access the buffer.
For read operations, the disk interface will read bytes from disk
into the buffer. This will set DRQ and clear EQ. The CPU may read data
from the buffer at any time after this occurs, and can continue to
read data until EQ goes high, indicating that the buffer is empty. CPU
reads from the data buffer will clear DRQ. If data is read from disk,
setting DRQ, and EQ also gets set, this indicates that the buffer is
now full. One more byte read from disk will set the LOST flag. The
LOST flag will remain set until the next command is written. This
condition will not usually occur when performing sectored reads of 512
bytes or less, since that is the buffer size.
For write operations, CPU data may be written to the buffer
before executing a write command, but may also be supplied during the
transfer. If the EQ flag is set after the CPU writes to the buffer,
clearing DRQ, this indicates that the buffer is now full, and that the
CPU should wait before stuffing more data. The the EQ flag goes high
with DRQ high, this indicates that the disk interface has used all of
the available data in the buffer. If one more byte is written to the
disk, the LOST flag will be set, indicating old buffer data has been
written to disk. The LOST flag will remain set until the next command
is written.
Data Transfer Commands
Execution of any of the Data Transfer Commands must be performed
assuming that the correct drive has been selected, the proper side has
been selected, and the drive's motor is on and has had time to spin
up. The read/write head(s) must be positioned over the track that data
is to be transferred to or from. If the status of the buffer pointers
is not as expected or required, a buffer pointer clear should be
performed before writing data or issuing commands.
All write commands should be performed with all bits in the clock
register set to a "1" (FF hex). This register is used only for
formatting diskettes. For all write operations, the WGATE status flag
indicates when data is actually being written to the diskette.
Sectored or formatted operations
These operations differ from free-format commands in that the use
of sectors is expected. Sectors are of fixed length, and are located
and read or written automatically. The disk control logic will verify
that the track/sector/side read from the address marks on the disk
match the track/sector/side register contents before transferring any
data. If the address marks do not match the address information
supplied by the user within 6 index pulses, the command will
terminate, BUSY will be reset, and the RNF (record not found) flag
will be set. The RNF flag will remain set until the next command is
issued. The RUN flag, when set, indicates that so far, the sector
being accessed appears to be correct. This flag will reset when any
part of the address mark does not match the expected data, or a
successful completion occurs. Therefore, RUN can change states several
times over single track.
RDS Read a Sector
Writing a 40 (hex) to the"command register will cause the
controller to execute a buffered RDS (read sector) command. Writing a
41 (hex) will execute an unbuffered RDS command. Add 4 to either
command to select DPLL data recovery instead of the normal FC method.
Add 6 to either command to select Alternate DPLL recovery instead of
the FC method.
The RDREQ flag, when set, indicates that the requested sector has
been found, and is now being read into the buffer. RDREQ will reset
after the last byte of the sector is read.
WTS Write a Sector
Writing a 80 (hex) to the command register will execute a
buffered WTS (write a sector) command. Add 1 to this command for
unbuffered operation, and add 4 if write pre compensation is desired.
The WTREQ flag, when set, indicates that the requested sector has
been found, and is now being written from the buffer. WTREQ will reset
after the last byte of the sector is written.
RDT Read a track
Writing a 60 (hex) to the command register will initiate an
unformatted buffered disk read. Add 1 to the command for unbuffered
operation. Reading will begin immediately, and will continue until
user cancellation. The data recovery logic will use address and data
marks to align data to byte boundaries. Add 4 to either command to
select DPLL data recovery instead of the normal FC method. Add 6 to
either command to select Alternate DPLL recovery instead of the FC
method.
WTT Write a track
Writing an A0 (hex) to the command register will initiate a
buffered write track operation. Add 1 to this command for unbuffered
operation, and add 4 to enable write precompensation.
The Write Track feature is usually only used for formatting
diskettes, and will most likely be used in the unbuffered mode, since
both data and clock must be supplied on a byte by byte basis. Write
normal data with the clock register set to FF hex. Write special marks
with missing clocks by writing an FB hex to the clock register.
Writing actually begins with the first index pulse after the
command is issued, and continues until the next index pulse.
STIN, STOUT Step In and Step Out
Writing a 10 (hex) or 18 (hex) to the command register will
initiate a Step-In or Step-Out operation, respectively. The stepping
pulse will be generated immediately, and BUSY will remain set for the
duration of the stepping time specified in the STEP register.
TIME General purpose timer
Writing a 14 (hex) to the command register will initiate a TIME
operation. BUSY will remain set for the duration of the time specified
in the STEP register. No stepping pulse will be generated.
SPIN Wait for motor spin-up
Writing a 20 (hex) to the command register will cause BUSY to be
set, and stay set for six index pulses. The RNF flag will be set at
the end of this operation.
CAN Cancel or "Can" the current operation
Writing a 0 to the command register will force cancellation of
any command in progress, and force BUSY to be reset after at least one
round-trip serial control and status transmission and reception.
CLB Clear buffer pointers
Writing a 1 to the command register will unconditionally reset
the buffer pointers. This should be considered a buffer clear
operation, although the contents of the buffer are not affected. The
BUSY flag will be set for at least one round-trip serial control and
status transmission and reception.
Full Track Writing and Formatting Diskettes
Writing full-track data and formatting are very similar. Both
will require that you generate the appropriate SYNC bytes, so that the
read data recovery logic can align the serial bitstream to byte
boundaries. Both descriptions, below, will assume that the spindle
motor is on, and up to speed, and that the read/write head is
positioned over the track and side to be written.
Track Writes
Full-track writes can be done, either buffered or unbuffered,
however, the CLOCK pattern register has no buffer, and writes to this
register must be done "one on one".
Write track Buffered
issue "clear buffer" command
write FF hex to clock register
issue "write track buffered" command
write FF hex to data register
wait for first DRQ flag
write A1 hex to data register
write FB hex to clock register
wait for next DRQ flag
write A1 hex to data register
wait for next DRQ flag
write A1 hex to data register
wait for next DRQ flag
write FF hex to clock register
write your first data byte to the data register
you may now use fully buffered operation.
Write Track Unbuffered
write FF hex to clock register
issue "write track unbuffered" command
write FF hex to data register
wait for first DRQ flag
write A1 hex to data register
write FB hex to clock register
wait for next DRQ flag
write A1 hex to data register
wait for next DRQ flag
write A1 hex to data register
wait for next DRQ flag
write FF hex to clock register
loop: write data byte to the data register
check BUSY flag for completion
wait for next DRQ flag
go to loop
Formatting a track
In order to be able to read or write sectored data on a diskette,
the diskette MUST be properly formatted. If, for any reason, marks are
missing or have improper clocks, track, sector, side, or length
information are incorrect, or the CRC bytes are in error, any attempt
to perform a sectored read or write operation will terminate with a
RNF error.
Formatting a track is simply writing a track with a strictly
specified series of bytes. A given track must be divided into an
integer number of sectors, which are 128, 256, 512, or 1024 bytes
long. Each sector must consist of the following information. All
clocks, are FF hex, where not specified. Data and clock values are in
hexadecimal notation. Fill any left-over bytes in the track with 4E
data.
quan data/clock description
---- ---------- -----------
12 00 gap 3*
3 A1/FB Marks
FE Header mark
(track) Track number
(side) Side number
(sector) Sector number
(length) Sector Length (0=128,1=256,2=512,3=1024)
2 (crc) CRC bytes
23 4E gap 2
12 00 gap 2
3 A1/FB Marks
FB Data mark
128,
256,
512, or
1024 00 Data bytes (consistent with length)
2 (crc) CRC bytes
24 4E gap 3*
* you may reduce the size of gap 3 to increase diskette capacity,
however the sizes shown are suggested.
Generating the CRC
The CRC is a sixteen bit value that must be generated serially,
one bit at a time. Think of it as a 16 bit shift register that is
broken in two places. To CRC a byte of data, you must do the following
eight times, (once for each bit) beginning with the MSB or bit 7 of
the input byte.
1. Take the exclusive OR of the MSB of the input byte and CRC
bit 15. Call this INBIT.
2. Shift the entire 16 bit CRC left (toward MSB) 1 bit position,
shifting a 0 into CRC bit 0.
3. If INBIT is a 1, toggle CRC bits 0, 5, and 12.
To Generate a CRC value for a header, or for a data field, you
must first initialize the CRC to all 1's (FFFF hex). Be sure to CRC
all bytes of the header or data field, beginning with the first of the
three A1 marks, and ending with the before the two CRC bytes. Then
output the most significant CRC byte (bits 8-15) and then the least
significant CRC byte (bits 7-0). You may also CRC the two CRC bytes.
If you do, the final CRC value should be 0.
Shown below is an example of code required to CRC bytes of data.
;
; CRC a byte. Assuming byte to CRC in accumulator and cumulative
; CRC value in CRC (lsb) and CRC+1 (msb).
CRCBYTE LDX #8 ; CRC eight bits
STA TEMP
CRCLOOP ASL TEMP ; shift bit into carry
JSR CRCBIT ; CRC it
DEX
BNE CRCLOOP
RTS
;
; CRC a bit. Assuming bit to CRC in carry, and cumulative CRC
; value in CRC (lsb) and CRC+1 (msb).
CRCBIT ROR
EOR CRC+1 ; MSB contains INBIT
PHP
ASL CRC
ROL CRC+1 ; shift CRC word
PLP
BPL RTS
LDA CRC ; toggle bits 0, 5, and 12 if INBIT is 1.
EOR #$21
STA CRC
LDA CRC+1
EOR #$10
STA CRC+1
RTS RTS
2.5.5. F011 Disk Expansion Port Serial Protocol
+-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +--
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | CLK
--+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+
+---------------------------------+ +--
| | | LD
-+ +---------------------+
--+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
|LED|MOT|STP|DIR|SID|DS2|DS1|DS0|SPR|DKI|DKC|IND|PRT|TK0| SERIO
--+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
Legend:
Outputs... Inputs...
LED Panel LED On TK0 Track Zero
MOT Spindle Motor On DKI Disk Inserted
STP Step Pulse DKC Disk Changed
DIR Step Direction IND Index
SID Side Select PRT Write Protect
DS2-DS0 Drive Unit Select SPR Spare input
The SERIO pin is bi-directional/and is used for both transmission
of drive control signals, and reception of drive status signals. The
F011 will drive SERIO when LD is high. The selected remote unit must
drive SERIO when LD is low. All SERIO bits are low-true. SERIO will
float high for non-existant drives, making all inputs look false.
All remote units must clock in serial data on the falling edge of
CLK. The remote units must update their control information on LD
falling if the DS bits match the given unit. All remote units may load
their status inputs when LD is high. Remote units shift out serial
status on the rising edge of CLK. The F011 will not change LD
coincident with CLK, nor will it drive SERIO when LD is changing.
2.5.6. F011 Disk Timing
UNBUFFERED WRITE
+-+ +-+
| | | | CTAK
-----+ +---------+ +-------------------
+-----+ +---------------
| | | DRQ
-----------+ +-----+
+-+ +-+ +-+
| | | | | | DTAK
-----------+ +---------+ +---+ +-------
+---------
| LOST
-----------------------------+
UNBUFFERED READ
+-+ +-+ +-+
| | | | | | DTAK
-----+ +---------+ +----+ +------------
+-----+ +---------------------
| | | DRQ
-----+ +-----+
+-+
| | DTAK
-----------+ +-------------------------
+----------
| LOST
----------------------------+
BUFFERED READ
+-+ +-+ +-+ +-+ +-+ +-+
| | | | | | | | | | | | DTAK
---+ +-------+ +---+ +-- --+ +-------+ +--+ +---
+----+ +---------- -------+ +----------
| | | | | DRQ
---+ +----+ +----+
----+ +----+ +----+ +----+
| | | | | | | EQ
+----+ +--------- ---+ +----+ +----
+-+ +-+
| | | | CTAK
-------+ +-------------- ------+ +--------------
+-----
| LOST
------------------------ -----------------+
BUFFERED WRITE
+-+ +-+ +-+ +-+
| | | | | | | | CTAK
---+ +-------+ +----------------- ---+ +--+ +---
+----+ +-------------- ---+
| | | | DRQ
--------+ +----+ ---+----------
----+ +----+ +----+ +----
| | | | | | EQ
+----+ +----+ +-------- ---------+
+-+ +-+ +-+ +-+
| | | | | | | | DTAK
-------+ +-------+ +--+ +---+ +-- --------------
+---------- --------------
| LOST
----------------------+ --------------
2.6. F016 Expansion Drive Controller
2.6.1. Description
The CSG4101-F016 is a disk expansion interface that is compatible
with the CSG4181-F011B disk controller. With the use of the F016, up
to seven external drives can be added to a base F011B system. Drive 0
is the main unit and is controlled entirely by the F011B. Drives 1
thru 7 are external drives, an each must be connected to the F011B
with a separate F016.
*** NOTE THAT THE C65 DOS SUPPORTS ONLY ONE EXTERNAL F016 EXPANSION DRIVE ***
CSG4101-F016 Pinout:
Pin Name Active Dir Type Description
--- ---- ------ --- ---- -----------
1 DS low output drive selected
2 MOT low output motor on
3 SIDE low output side select
4 WPROT low input write protect
5 TKO low input track 0
6 INDEX low input index
7 DR2 low input pullup drive assign dipswitch
8 DR1 low input pullup drive assign dipswitch
9 DR0 low input pullup drive assign dipswitch
10 GND power
11 RES low input master reset
12 LED low output panel LED
13 DIR output stepping direction
14 STEP low output stepping command
15 SPARE input
16 DSKIN low input disk inserted
17 SERIO low I/O bidir serial data
18 CLK input serial data clock
19 LD input shift/load command
20 VCC power
Signal descriptions:
RES The Reset is a low-true input used to reset internal flip-
flops. The DS (drive selected) output will go false (high)
when RES is asserted (low).
WPROT The Write Protect input must indicate, when true, that the
diskette in the attached drive must not be written to (the
drive itself will inhibit writing, as well).
DR This output, when low, indicates that the attached drive is
the currently selected drive. This signal will become false
(high) upon RESet and when another drive is selected.
DSKIN The Disk In Input must indicate when a diskette is physically
in the attached drive, and the drive is available for use.
MOT The Motor On output, when true, turns on the motor of the
attached disk drive.
LED The LED output, when true turns on the panel Light-emitting-
diode of the attached disk drive.
SIDE The Side select output determines which side of the media is
to be read or written. It is high (false) for side 0, and low
(true) for side 1.
STEP The Step output provides a low-going pulse when a head step
operation is required, assuming DS is true (low).
DIR The Direction output indicates to the drives whether the read/
write head is to step toward track 0 (DIR=high) or away from
track 0 (DIR=low) when a step pulse is received, assuming DS
is true (low).
TK0 The Track Zero input must determine when the read/write head
of the attached drive is positioned over track zero.
INDEX The Index pulse input must provide a low going pulse for each
spindle rotation of the attached drive, if it has an index
sensor. The F016 will latch index pulses until they are sent
out via the SERIO line. This input must be tied low if the
attached drive has no index sensor.
SERIO The Serial I/O line is a bi-directional signal that is used
to receive control information from the main disk controller,
and return status information to the main controller, assuming
the DS output is true (low). It is a driven output when LD and
DS are low, and an input, otherwise.
LD The Load Data input tells when to update control information
shifted over the SERIO line, when to load status information
for shifting, and when to drive the SERIO line.
CLK The Clock input is used for shifting control and status
information.
2.6.2. Expansion Port Timing
(used by all F016 chips)
+-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +--
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | CLK
--+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+
+---------------------------------+ +--
| | | LD
-+ +---------------------+
--+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
|LED|MOT|STP|DIR|SID|DS2|DS1|DS0|SPR|DKI|DKC|IND|PRT|TK0| SERIO
--+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
Legend:
Outputs... Inputs...
LED Panel LED On TK0 Track Zero
MOT Spindle Motor On DKI Disk Inserted
STP Step Pulse DKC Disk Changed
DIR Step Direction IND Index
SID Side Select PRT Write Protect
DS2-DS0 Drive Unit Select SPR Spare Input
The SERIO pin is bi-directional, and is used for both
transmission of drive control signals, and reception of drive status
signals. The F011B will drive SERIO when LD is high. Any selected F016
will drive SERIO when LD is low. All SERIO bits are low-true. SERIO
will float high for nonexistant drives, making ail inputs look false.
All F016 chips clock in serial data on the falling edge of CLK.
They update their control information on LD falling if the DS bits
match the DS0-DS2 switch settings. All F016 chips load their status
inputs when LD is high, and shift out serial status on the rising edge
of CLK.
2.7. DMAgic DMA CONTROLLER F018 (Preliminary)
A more detailed documentation is at section 4.
2.7.1. F018 DESCRIPTION
DMAGIC is a custom DMA Gate array IC used in the C65. It
functions as a DMA controller with a few tricks up its sleeve.
Specifically, DMAgic provides the following commands:
* COPY -- Copy a block of memory to another area in memory.
* MIX -- Perform a boolean Minterm mix of a source block of
memory with a destination block of memory.
* SWAP -- Exchange the contents of two blocks of memory.
* FILL -- Fill a block of memory with a source byte.
Special features include:
* List-based fetching of DMA command sequences.
* Ability to CHAIN multiple DMA command sequences.
* Absolute Address access to entire System Memory (1MB).
* Blocks can be up to 64K bytes long.
* Windowed Block capability using MODulus function.
* DMAgic operations yield to VIC video and external DMA accesses.
* DMAgic operations can optionally yield to system interrupts.
* Interrupted DMAgic operations can be continued/resumed, or
cancelled.
* Data ReQuest handshaking support for 10 devices.
* Independent memory/mapped IO selection for source and destination.
* Independent memory tranfer DIRection for source and destination.
* Independent MODulus enable for source and destination.
* Independent HOLD (fixed pointer) for source and destination.
The DMA controller has 4 registers:
0 DMA List address low, Triggers DMA (write only)
1 DMA List address high (write only)
2 DMA List address bank (write only)
3 DMA Status (b7=busy, b0=chained) (read only)
(a read will restart an INTerupted DMA operation)
Note: Minterms & Subcommand will not be implemented until F018A, at
which time the register map will be reorganized & support for
the REC added.
dma_ctlr = $D700 ;DMA Controller
2.7.2. F018 REGISTERS.
F018 DMA CONTROLLER
REG R
NAME # B7 B6 B5 B4 B3 B2 B1 B0
+-------+-------+-------+-------+-------+-------+-------+-------+
| | __ | __ | ____ | ___ | | | |
COMMAND 0 | SADA | SADA | SADA | SADA | INT | CHAIN | OPERATION |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
CNT LO 1 | C7 | C6 | C5 | C4 | C3 | C2 | C1 | C0 |
(COL) | | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
CNT HI 2 | C15 | C14 | C13 | C12 | C11 | C10 | C9 | C8 |
(ROW) | | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
SRC LO 3 | SA7 | SA6 | SA5 | SA4 | SA3 | SA2 | SA1 | SA0 |
(FILL) | | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
SRC HI 4 | SA15 | SA14 | SA13 | SA12 | SA11 | SA10 | SA9 | SA8 |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
| _ | | | | | | | |
SRC BANK 5 | I/O | DIR | MOD | HOLD | SA19 | SA18 | SA17 | SA16 |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
DEST LO 6 | DA7 | DA6 | DA5 | DA4 | DA3 | DA2 | DA1 | DA0 |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
DEST HI 7 | DA15 | DA14 | DA13 | DA12 | DA11 | DA10 | DA9 | DA8 |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
| _ | | | | | | | |
DEST BANK 8 | I/O | DIR | MOD | HOLD | DA19 | DA18 | DA17 | DA16 |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
MOD LO 9 | M7 | M6 | M5 | M4 | M3 | M2 | M1 | M0 |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
| | | | | | | | |
MOD HI 10 | M15 | M14 | M13 | M12 | M11 | M10 | M9 | M8 |
| | | | | | | | |
+-------+-------+-------+-------+-------+-------+-------+-------+
OPERATIONS: 0 0 COPY
0 1 MIX (MINTERMS ACTIVE)
1 0 SWAP
1 1 FILL (SRC LO = FILL BYTE)
___
PARAMETERS: INT 0 NO INTERRUPTION
1 IRQ/NMI INTERRUPTION
CHAIN 0 LAST COMMAND IN LIST
1 PERFORM NEXT COMMAND
BOOLEAN MINTERMS: DA
0 | 1
+--------+--------+
| ____ | __ |
0 | SADA | SADA |
|0 |1 |
SA +--------+--------+
| __ | |
1 | SADA | SADA |
|2 |3 |
+--------+--------+
THE ABOVE COMMANDS ARE NOT YET IMPLEMENTED, AND SOME OF THE REGISTER
BITS DEFINED ARE DIFFERENT IN THE PILOT VERSIONS.
2.8. RAM Expansion Controller
2.8.1. Functional Specification
C65 RAM EXPANSION FUNCTIONAL SPECIFICATION
*** THIS IS PRELIMINARY AND WILL BE CHANGING ***
The C65 RAM Expansion Card (REC) provides 1 megabyte of expansion
RAM for the C65 computer. The C65 4510/VIC-III provides 1MB of address
space, but rudimentary banking capability is provided by the REC to
allow several different memory configurations for both the CPU and the
VIC-III via available chip selects.
The REC presumes the following system memory map:
$00000-$1FFFF 128K internal RAM
$20000-$3FFFF 128K for internal System ROM
$40000-$7FFFF 256K reserved for cartridge expansion
$80000-$FFFFF 512K reserved for RAM expansion
The REC contains a four-bit write-only register. Data is read
from the four low-order bits of the data bus. Reset forces all of
these bits into the reset (low) state. The four bits are defined as:
____CPU bank select
/____VIC access enable
//____VIC address range
///____VIC Bank select
////
3210 VIC sees:
---- -----------------------------------------------------
x0xx Internal RAM $00000-$1FFFF
x100 Expansion RAM bank 0, physical address $C0000-$DFFFF
x110 Expansion RAM bank 0, physical address $E0000-$FFFFF
x101 Expansion RAM bank 1, physical address $C0000-$DFFFF
x111 Expansion RAM bank 1, physical address $E0000-$FFFFF
CPU sees (note that DMA and VIC-DAT access see this too):
---- --------------------
0xxx Expansion RAM bank 0
1xxx Expansion RAM bank 1
/* Inputs */
PIN 1 = MEMCLK ; /* System memory clock */
PIN 2 = !CAS ; /* Correct timing for CAS signal */
PIN 3 = AEC ; /* The VIC is in town */
PIN 4 = B3 ; /* bit to control CPU accesses */
PIN 5 = A19 ; /* high order address lines */
PIN 6 = A18 ;
PIN 7 = A17 ;
PIN 8 = A16 ;
PIN 9 = A7 ;
PIN 10 = RW ;
PIN 11 = !SID ; /* Chip select for SID. Used as a decode */
PIN 13 = B2 ; /* bits to control VIC accesses */
PIN 14 = B1 ;
PIN 23 = B0 ;
* Outputs */
PIN 15 = 'CAS0B ; /* Cases for the DRAMS */
PIN 16 = !CAS0A ;
PIN 17 = 'CAS1B ;
PIN 18 = !CAS1A ;
PIN 19 = !EXPAND ; /* Signal to system to allow internal ram out */
PIN 20 = MA8 ; /* High order Memory address line DRAMS */
PIN 21 = !BRDGOE ; /* Enable for the Gardei Bridge */
PIN 22 = EX_LATCH ; /* Strobe for user write to control latch */
VIC = !AEC ;
RAST = !MEMCLK ;
CAST = MEMCLK ;
EXVIC = B0 ;
VICSEL0 = B1 ;
VICSEL1 = B2 ;
CPUBANK = B3 ;
EX_LATCH = CAS & SID & A7 & !RW ; /* location of control register */
/* latch data on cas fall to avoid the phi-2 hold time problem */
BRDGOE = EXPAND & A16 & !VIC ; /* CPU accessing E bank side */
EXPAND = !VIC & A19 /* ram area */
# VIC & EXVIC ; /* external vie accesses allowed */
MA8 = VIC & RAST 6 ;A16 /* Ras time, keep upper */
# VIC & CAST & VICSEL0 /* Cas time, programable */
# !VIC & RAST & A18 /* ras time */
# !VIC & CAST & A17 ; /* cas time */
/* bank 0 drams */
CAS0A = CAS & EXPAND & ( !VIC & !CPUBANK & !A16 # VIC & !VICSEL1 ) ;
CAS0B = CAS & EXPAND & ( !VIC & !CPUBANK & A16 # VIC & !VICSEL1 ) ;
/* bank 1 drams */
CAS1A = CAS & EXPAND & ( !VIC & CPUBANK & !A16 # VIC & VICSEL1 );
CAS1B = CAS & EXPAND & ( !VIC & CPUBANK & A16 # VIC & VICSEL1 );
2.9. 8580 SID REGISTER MAP
7 6 5 4 3 2 1 0
+------+------+------+------+------+------+------+------+
0 | F7 | F6 | F5 | F4 | F3 | F2 | F1 | F0 | FREQUENCY LO VOICE-1
1 | F15 | F14 | F13 | F12 | F11 | F10 | F9 | F8 | FREQUENCY HI
2 | PW7 | PW6 | PW5 | PW4 | PW3 | PW2 | PW1 | PW0 | PULSE WIDTH LO
3 | | | | | PW11 | PW10 | PW9 | PH8 | PULSE WIDTH HI
4 | NOISE| PULSE| SAW | TRI | TEST | RING | SYNC | GATE | CONTROL REGISTER
5 | ATK3 | ATK2 | ATK1 | ATK0 | DCY3 | DCY2 | DCY1 | DCY0 | ATTACK / DECAY
6 | STN3 | STN2 | STN1 | STN0 | RLS3 | RLS2 | RLS1 | RLS0 | SUSTAIN / RELEASE
+------+------+------+------+------+------+------+------+
7 | F7 | F6 | F5 | F4 | F3 | F2 | F1 | F0 | FREQUENCY LO VOICE-2
8 | F15 | F14 | F13 | F12 | F11 | F10 | F9 | F8 | FREQUENCY HI
9 | PW7 | PW6 | PW5 | PW4 | PW3 | PW2 | PW1 | PW0 | PULSE WIDTH LO
10 | | | | | PW11 | PW10 | PW9 | PH8 | PULSE WIDTH HI
11 | NOISE| PULSE| SAW | TRI | TEST | RING | SYNC | GATE | CONTROL REGISTER
12 | ATK3 | ATK2 | ATK1 | ATK0 | DCY3 | DCY2 | DCY1 | DCY0 | ATTACK / DECAY
13 | STN3 | STN2 | STN1 | STN0 | RLS3 | RLS2 | RLS1 | RLS0 | SUSTAIN / RELEASE
+------+------+------+------+------+------+------+------+
14 | F7 | F6 | F5 | F4 | F3 | F2 | F1 | F0 | FREQUENCY LO VOICE-3
15 | F15 | F14 | F13 | F12 | F11 | F10 | F9 | F8 | FREQUENCY HI
16 | PW7 | PW6 | PW5 | PW4 | PW3 | PW2 | PW1 | PW0 | PULSE WIDTH LO
17 | | | | | PW11 | PW10 | PW9 | PH8 | PULSE WIDTH HI
18 | NOISE| PULSE| SAW | TRI | TEST | RING | SYNC | GATE | CONTROL REGISTER
19 | ATK3 | ATK2 | ATK1 | ATK0 | DCY3 | DCY2 | DCY1 | DCY0 | ATTACK / DECAY
20 | STN3 | STN2 | STN1 | STN0 | RLS3 | RLS2 | RLS1 | RLS0 | SUSTAIN / RELEASE
+------+------+------+------+------+------+------+------+
21 | | | | | | FC2 | FC1 | FC0 | FREQUENCY LO FILTER
22 | FC10 | FC9 | FC8 | FC7 | FC6 | FC5 | FC4 | FC3 | FREQOENCY HI
23 | RES3 | RES2 | RES1 | RES0 |FILTEX| FILT3| FILT2| FILT0| RESONANCE / FILTER
24 | 3 OFF| HP | BP | LP | VOL3 | VOL2 | VOL1 | VOL0 | MODE / VOLUME
+------+------+------+------+------+------+------+------+
25 | PX7 | PX6 | PX5 | PX4 | PX3 | PX2 | PX1 | PX0 | POT X MISC.
26 | PY7 | PY6 | PY5 | PY4 | PY3 | PY2 | PY1 | PY0 | POT Y
27 | O7 | O6 | O5 | O4 | O3 | O2 | O1 | O0 | OSCILLATOR 3
28 | E7 | E6 | E5 | E4 | E3 | E2 | E1 | E0 | ENVELOPE 3
+------+------+------+------+------+------+------+------+
Notes:
1. CIA#1 ports PRA6 and PRA7 select which control port POT line
is routed to SID.
2. While there are 2 SIDs in the C65, the POT lines are still
routed to SID#1 for C64 compatibility reasons.
3.0. System Software
3.1. BASIC 10.0
C64DX BASIC 10.0
3.1.1. INTRODUCTION
This section lists BASIC 10.0 commands, statements, and functions
in alphabetical order. It gives a complete list of the rules (syntax)
of BASIC 10.0, along with a concise description of each.
COMMAND AND STATEMENT FORMAT
The commands and statements presented in this section are
governed by consistent format conventions designed to make them as
clear as possible. In most cases, there are several actual examples to
illustrate what the actual command looks like. The following example
shows some of the format conventions that are used in the BASIC
commands:
EXAMPLE: DLOAD <"program name"|(file_name_var)> [,U#] [,D#]
| | | |
| | | |
keyword argument (if any) optional arguments
The parts of the command or statement that the user must type in
exactly as they appear are in capital letters. Words that don't have
to be typed exactly, such as the name of the program, are not
capitalized. When quote marks (" ") appear (usually around a program
or file name), the user should include them in the appropriate place
according, to the format example.
KEYWORDS, also called RESERVED WORDS, appear in uppercase
letters. THESE KEYWORDS MUST BE ENTERED EXACTLY AS THEY APPEAR.
However, many keywords have abbreviations that can also be used.
Keywords are words that are part of the BASIC language that the
computer understands. Keywords are the central part of a command or
statement. They tell the computer what kind of action to take. These
words cannot be used as variable names.
ARGUMENTS (also called parameters) appear in lower case.
Arguments are the parts of a command or statement; they complement
keywords by providing specific information about the command or
statement. For example, a keyword tells the computer to load a
program, while the argument tells the computer which specific program
to load and a second argument specifies which drive the disk
containing the program is in. Arguments include filenames, variables,
line numbers, etc.
SQUARE BRACKETS [] show OPTIONAL arguments. The user selects any
or none of the arguments listed, depending on the requirements.
ANGLE BRACKETS <> indicates that the user MUST choose one of the
arguments listed.
VERTICAL BAR | separates items in a list of arguments when the
choices are limited to those arguments listed, and no other arguments
can be used. Then the vertical bar appears in a list enclosed in
SQUARE BRACKETS, the choices are limited to the items in the list, but
still have the option not to use any arguments.
ELLIPSIS ..., a sequence of three dots, means that an option or
argument can be repeated more than once.
QUOTATION MARKS " " enclose character strings, filenames, and
other expressions. When arguments are enclosed in quotation marks in a
format, the quotation marks must be included in a command file or
statement. Quotation marks are not conventions used to describe
formats; they are required parts of a command or statement.
PARENTHESES () When arguments are enclosed in parentheses in a
format, they must be included in a command or statement. Parentheses
are not conventions used to describe formats; they are required parts
of a command or statement.
VARIABLE refers to any valid BASIC variable name such as X, A$,
or T%.
EXPRESSION means any valid BASIC expression, such as A+B+2 or
.5*(X+3).
3.1.2. ALPHABETICAL LIST OF COMMANDS, FUNCTIONS, and OPERATORS
* Token = AC multiplication
+ Token = AA addition
- Token = AB subtraction
/ Token = AD division
< Token = B3 less-than
= Token = B2 equal
> Token = B1 greater-than
^ Token = AE exponentiation
(PI) Token = FF return value of PI
ABS Token = B6 absolute function
AND Token = AF logical AND operator
APPEND Token = FE,0E append file
ASC Token = C6 string to PETSCII function
ATN Token = C1 trigonometric arctangent function
AUTO Token = DC auto line numbering
BACKGROUND Token = FE,3B background color
BACKUP Token = F6 backup diskette
BANK Token = FE,02 memory bank selection
BEGIN Token = FE,18 start logical program block
BEND Token = FE,19 end logical program block
BLOAD Token = FE,11 binary load file from diskette
BOOT Token = FE,1B load & run ML, or BASIC autoboot
BORDER Token = FE,3C border color
BOX Token = E1 draw graphic box
BSAVE Token = FE,10 binary save to disk file
BUMP Token = CE,03 sprite collision function
BVERIFY Token = FE,28 verify memory to binary file
CATALOG Token = FE,0C disk directory
CHANGE Token = FE,2C edit program
CHAR Token = E0 display characters on screen
CHR$ Token = C7 PETSCII to string function
CIRCLE Token = E2 draw graphic circle
CLOSE Token = A0 close channel or file
CLR Token = 9C clear BASIC variables, etc.
CMD Token = 9D set output channel
COLLECT Token = F3 validate diskette (chkdsk)
COLLISION Token = FE,17 enable BASIC event
COLOR Token = E7 set screen colors
CONCAT Token = FE,13 concatenate two disk files
CONT Token = 9A continue BASIC program execution
COPY Token = F4 copy a disk file
COS Token = BE trigonometric cosine function
CUT Token = E4 cut graphic area
DATA Token = 83 pre-define BASIC program data
DCLEAR Token = FE,15 mild reset of disk drive
DCLOSE Token = FE,0F close disk channel or file
DEC Token = D1 decimal function
DEF Token = 96 define user function
DELETE Token = F7 delete BASIC lines or disk file
DIM Token = 86 dimension BASIC array
DIR Token = EE disk directory
DISK Token = FE,40 send disk special command
DLOAD Token = F0 load BASIC program from disk
DMA Token = FE,1F define & execute DMA command
DMA Token = FE,21 "
DMA Token = FE,23 "
DMODE Token = FE,35 set graphic draw mode
DO Token = EB start BASIC loop
DOPEN Token = FE,0D open channel to disk file
DPAT Token = FE,36 set graphic draw pattern
DSAVE Token = EF save BASIC program to disk
DVERIFY Token = FE,14 verify BASIC memory to file
ELLIPSE Token = FE,30 draw graphic ellipse
ELSE Token = D5 if/then/else clause
END Token = 80 end of BASIC program
ENVELOPE Token = FE,0A define musical instrument
ERASE Token = FE,2A delete disk file
ERRS Token = D3 BASIC error function
EXIT Token = FD exit BASIC loop
EXP Token = BD exponentiation function
FAST Token = FE,25 set system speed to maximum
FILTER Token = FE,03 set audio filter parameters
FIND Token = FE,2B hunt for string in BASIC program
FN Token = A5 define user function
FOR Token = 81 start BASIC for/next loop
FOREGROUND Token = FE,39 set foreground color
FRE Token = B8 available memory function
GCOPY Token = FE,32 graphic copy
GENLOCK Token = FE,38 set video sync mode
GET Token = Al receive a byte of input
GO Token = CB program branch
GOSUB Token = 8D program subroutine call
GOTO Token = 89 program branch
GRAPHIC Token = DE set graphic mode
HEADER Token = F1 format a diskette
HELP Token = EA display BASIC line causing error
HEX$ Token = D2 return hexadecimal string function
HIGHLIGHT Token = FE,3D set highlight color
IF Token = 8B if/then/else conditional
INPUT Token = 85 receive input data from keyboard
INPUT# Token = 84 receive input data from channel (file)
INSTR Token = D4 locate a string within a string
INT Token = B5 integer function
JOY Token = CF joystick position function
KEY Token = F9 define or display function key
LEFT$ Token = C8 leftmost substring function
LEN Token = C3 length of string function
LET Token = 88 variable assignment
LINE Token = E5 draw graphic line, input line
LIST Token = 9B list BASIC program
LOAD Token = 93 load program from disk
LOCATE Token = E6 (currently unimplemented)
LOG Token = BC natural log function
LOOP Token = EC end of do/loop
LPEN Token = CE,04 lightpen position function
MID$ Token = CA substring function
MONITOR Token = FA enter ML Monitor mode
MOUSE Token = FE,3E set mouse parameters
MOVSPR Token = FE,06 set sprite position and speed
NEW Token = A2 clear BASIC program area
NEXT Token = 82 end of for-next loop
NOT Token = A8 logical complement function
OFF Token = FE,24 (subcommand)
ON Token = 91 multiple branch or subcommand
OPEN Token = 9F open I/O channel
OR Token = B0 logical or function
PAINT Token = DF graphic flood-fill
PALETTE Token = FE,34 set palette color
PASTE Token = E3 draw graphic area from cut buffer
PEEK Token = C2 return memory byte function
PEN Token = FE,33 set graphic pen color
PIC Token = FE,37 graphic subcommand
PLAY Token = FE,04 play musical notes from string
POINTER Token = CE,0A address of string var function
POKE Token = 97 change memory byte
POLYGON Token = FE,2F draw graphic polygon
POS Token = B9 text cursor position function
POT Token = CE,02 return paddle position
PRINT Token = 99 display data on text screen
PRINT# Token = 98 send data to channel (file)
PUDEF Token = DD define print-using symbols
QUIT Token = FE,1E (currently unimplemented)
RCLR Token = CD (currently unimplemented)
RDOT Token = D0 (currently unimplemented)
READ Token = 87 read program pre-defined program data
RECORD Token = FE,12 set relative disk file record pointer
REM Token = 8F BASIC program comment
RENAME Token = F5 rename disk file
RENUMBER Token = F8 renumber BASIC program lines
RESTORE Token = 8C set DATA pointer, subcommand
RESUME Token = D6 resume BASIC program after trap
RETURN Token = 8E end of subroutine call
RGR Token = CC (currently unimplemented)
RIGHT$ Token = C9 rightmost substring function
RMOUSE Token = FE,3F read mouse position
RND Token = BB pseudo random number function
RREG Token = FE,09 return processor registers after SYS
RSPCOLOR Token = CE,07 return sprite color function
RSPPOS Token = CE,05 return sprite position function
RSPRITE Token = CE,06 return sprite parameter function
RUN Token = 8A run BASIC program from memory or disk
RWINDOW Token = CE,09 return text window parameter function
SAVE Token = 94 save BASIC program to disk
SCALE Token = E9 (currently unimplemented)
SCNCLR Token = E8 erase text or graphic display
SCRATCH Token = F2 delete disk file
SCREEN Token = FE,2E set parameters or open graphic screen
SET Token = FE,2D set system parameter, subcommand
SGN Token = B4 return sign of number function
SIN Token = BF trigonometric sine function
SLEEP Token = FE,0B pause BASIC program for time period
SLOW Token = FE,26 set system speed to minimum
SOUND Token = DA perform sound effects
SPC Token = A6 skip spaces in printed output
SPRCOLOR Token = FE,08 set multicolor sprite colors
SPRDEF Token = FE,1D (currently unimplemented)
SPRITE Token = FE,07 set sprite parameters
SPRSAV Token = FE,16 set or copy sprite definition
SQR Token = BA Square root function
STEP Token = A9 for-next step increment
STOP Token = 90 halt BASIC program
STRS Token = C4 string representation of number function
SYS Token = 9E call ML routine
TAB Token = A3 tab position in printed output
TAN Token = C0 trigonometric tangent function
TEMPO Token = FE,05 set tempo (speed) of music play
THEN Token = A7 if/then/else clause
TO Token = A4 (subcommand)
TRAP Token = D7 define BASIC error handler
TROFF Token = D9 BASIC trace mode disable
TRON Token = D8 BASIC trace mode enable
TYPE Token = FE,27 display sequential disk file
UNTIL Token = FC do/loop conditional
USING Token = FB define print output format
USR Token = B7 call user ML function
VAL Token = C5 numeric value of a string function
VERIFY Token = 95 compare memory to disk file
VIEWPORT Token = FE,31 (currently unimplemented)
VOL Token = DB set audio volume
WAIT Token = 92 pause program pending memory condition
WHILE Token = ED do/loop conditional
WIDTH Token = FE,1C (currently unimplemented)
WINDOW Token = FE,1A set text screen display window
XOR Token = CE,08 logical xor function
3.1.3. BASIC 10.0 COMMAND AND FUNCTION DESCRIPTION
ABS -- Absolute value function
ABS (expression)
The ABSolute value function returns the unsigned value of the numeric
expression.
X = ABS(1) Result is X = 1
X = ABS(-1) Result is X = 0
AND -- Boolean operator
expression AND expression
The AND operator returns a numeric value equal to the logical AND of
two numeric expressions, operating on the binary value of signed
16-bit integers in the range (-32768 to 32767). Numbers outside this
range result in an 'ILLEGAL QUANTITY' error.
X = 4 AND 12 Result is X=4
X = 8 AND 12 Result is X=8
X = 2 AND 12 Result is X=0
In the case of logical comparisons, the numeric value of a true
situation is -1 (equivalent to 65535 or $FFFF hex) and the numeric
value of a false situation is zero.
X = ("ABC"="ABC") AND ("DEF"="DEF") Result is X=-1 (true)
X = ("ABC"="ABC") AND ("DEF"="XYZ") Result is X= 0 (false)
APPEND -- Open a disk file and prepare to append data to it
APPEND# logical_file_number, "filename" [,Ddrive] [<ON|,>Udevice]
Opens filename for writing, and positions the file pointer at the end
of the file. Subsequent PRINT# statements to the logical_file_number
will cause data to be appended to the end of this file. If the file
does not exist, it will be created.
APPEND#1, "filename"
APPEND#1, (file$), ON U(unit)
ASC -- PETSCII value function
ASC (string)
This function returns the PETSCII numeric value of the first
character of a string. The PETSCII value of an empty (null) string is
zero. This function is the opposite of the CHR$ function. Refer to the
Table of PETSCII Character Codes.
X = ASC("ABC") Result is X=65
X = ASC("") Result is X=0
ATN -- Arc tangent function
ATN (expression)
This function returns the angle whose tangent is the value of the
numeric expression, measured in radians. The result is in the range
of -PI/2 to PI/2 radians.
X = ATN(45) Result is X=1.54050257
To get the arc tangent of an angle measured in degrees, multiply the
numeric expression by PI/180.
AUTO -- Enable or disable automatic line numbering
AUTO [increment]
Turns on the automatic line numbering feature which eases the job of
entering programs by typing the line numbers for the user. As each
program line is entered by pressing <RETURN> the next line number is
printed on the screen, with the cursor in position to begin typing
that line. The increment parameter refers to the increment between
line numbers. AUTO with no increment given turns off auto line
numbering. AUTO mode is also turned off automatically when a program
is RUN. This statement is executable only in direct mode.
AUTO 10 automatically numbers line in increments of ten.
AUTO 50 automatically numbers line in increments of fifty.
AUTO turns off automatic line numbering.
BACKGROUND -- Set the background color of the display
BACKGROUND color
Sets the screen background color to the given color. The color given
must be in the range (0-15). See the Color Table.
BACKUP -- Backup an entire disk from one drive to another
BACKUP Dsource_drive TO Ddestination_drive [<ON|,>Udevice]
This command copies all the files on a diskette to another on a dual
drive system only. It cannot backup diskettes using CBM serial bus
type drives, for example. If the destination diskette is unformatted,
BACKUP will automatically format it. BACKUP copies every sector, so
any data already on the destination diskette will be overwritten. To
copy specific files from one drive to another, use the COPY command.
NOTE: This command can only be used with a dual disk drive, such as
the built-in C64DX drive and optional F016-type expansion drive. To
backup diskettes using different drives, such as the built-in drive
and a 1581-type serial bus drive, use a utility program.
BACKUP D0 to D1 Copies all files from the disk in
drive 0 to the disk in drive 1.
BACKUP D0 TO D1, ON U9 Copies all files from drive 0 to
drive 1 in disk drive unit 9.
BANK -- Set the memory bank number for PEEK, POKE, SYS, WAIT, LOAD, SAVE
BANK memory_bank
[*** THIS COMMAND MIGHT CHANGE ***]
This command should be used before and BASIC command that has an
address parameter. The address parameters are limited to the range
(0-65535, $0000-$FFFF hex). The BANK command tells the computer which
64K byte memory bank the location you want is in.
The memory_bank parameter is number from 0-255. Refer to the System
memory map to see what is in each bank. A BANK number greater than
127 (i.e., has its most significant bit set) means "use the current
system configuration", and must be used to access an I/O location.
BASIC defaults to BANK 128.
For examples, see PEEK, POKE, etc.
BEGIN/BEND -- Extend an IF clause over more than one line
BEGIN/BEND are used to define a block of code which is considered by
the IF statement to be one statement.
The normal usage of IF/THEN/ELSE would be along the following lines:
IF boolean THEN statement(s) : ELSE statement(s)
The main restriction is that the entire body of the IF/THEN/ELSE
construct can only occupy one line. BEGIN/BEND allows either the
'THEN' or the 'ELSE' clause to run on for more than one line.
IF boolean THEN BEGIN: statements...
statements...
statements... BEND : ELSE BEGIN
statements...
statements... BEND
Remember, however, that this is only a way to extend the body for more
than one line: all other 'IF/THEN' rules apply. For example:
100 IF x=1 THEN BEGIN : a=5
110 : b=6
120 : c=7
130 BEND : print "ah-ha!"
In the above example, "ah-ha!" would be printed ONLY if the expression
'x=1' is TRUE, because the print statement is on the same logical line
as the THEN clause.
It is bad practice to GOTO a line in the middle of a BEGIN-BEND block.
If BEGIN or BEND is encountered outside of an active IF statement, it
is ignored.
BLOAD -- loads a binary disk file into memory
BLOAD "filename" [,Bbank] [,Paddress] [<ON|,>Udevice]
Used to load a machine language program or other binary data (such as
display pictures or sprite data) into memory. If a load address is
not given, the load address given in the disk file will be used. If a
bank number is not given, the bank given in the last BANK statement
will be used. If a load overflows a bank (that is, the load address
exceeds 65535 ($FFFF)), an 'OUT OF MEMORY' error is reported. Also see
the LOAD command.
BLOAD "sprites", P(dec("600")), B0
BOOT -- Load and execute a program
BOOT
BOOT SYS
BOOT filename [,Bbank] [,Paddress] [,Ddrive] [<ON|,>Udevice]
BOOT without a filename given causes the computer to look for a BASIC
program called AUTOBOOT.C65* on the indicated diskette, LOAD it and
RUN it (just like RUN "AUTOBOOT.C65*").
BOOT with a filename given will cause the executable binary file to be
BLOADed and executed beginning at the load address. If a load address
is not given, the file will be loaded and execution begun at the
address stored on disk.
BOOT SYS is a special command that copies the "home" sector (the very
track and sector) of the C64DX built-in drive into memory at address
$400 to $5FF (one physical sector, 512 bytes) and perform a machine
language JSR (Jump SubRoutine) to it. It has the same function as
turning on your C64DX while holding down the ALT key. It is used to
boot an alternate operating system from either a CBM 3.5" diskette or
an MSDOS (720K) diskette. If used in a BASIC program, and it fails,
the system can be corrupted. BOOT SYS does *not* use the normal DOS
to access the disk.
BOOT Loads & runs BASIC program called
AUTOBOOT.C65* on system disk.
BOOT U9 Loads & runs BASIC program called
AUTOBOOT.C65* on disk unit 9.
BOOT "ml" Load & executes machine language
program called ML, starting at address
stored on disk.
BORDER -- Set the exterior border color of the display
BORDER color
Sets the screen border color to given color. The color must be in the
range (0-15). See the Color Table.
BOX -- Draw a 4-sided graphical shape
BOX x0,y0, x1,y0, x0,y1, x1,y1 [,solid]
Requires two line segments to be specified, the order of which
determines the shape drawn. The shape is drawn in the currently
specified PEN color, on the currently specified SCREEN. The above
command will draw the following shape:
|0,<=0 +--------------------+ |1,<=0
| |
| |
|0,<=1 +--------------------+ |1,<=1
But if the order of the coordinates were given as:
BOX x0,y0, x1,y0, x1,y1, x0,y1
a "bowtie" shape would be drawn. See the sample program at SCREEN.
BSAVE -- Save an area of memory in binary disk file
BSAVE "[@]filename", Pstart_adr TO Pend_adr [,Bbank] [,Ddrive]
[<ON|,>Udevice]
BSAVE copies an area of memory into a binary disk file called
"filename", starting at start_adr and ending at end_adr-1 (i.e.
end_adr must be one more than actual last address saved). If a bank
number is not given, the bank given in the last BANK statement will
be used. end_adr must be greater than start_adr, and area to be saved
must be limited to the indicated memory bank. You cannot save data
from more than one bank at a time. start_adr is saved on disk as the
load address. If filename already exists on the designated diskette,
memory is NOT saved and a 'FILE EXISTS' error is reported. Preceding
the filename with an '@'-sign will allow you to overwrite an existing
file, but see the cautions at DSAVE.
BSAVE "sprites", P(dec("600")) TO P(dec("800")), B0
BUMP -- Sprite collision function
BUMP (type)
This function return a numeric summary of sprite collisions
accumulated since the last time the BUMP function was used.
You can use the COLLISION command to set up a special routine in your
program to receive control whenever a sprite BUMPs into something, but
a particular COLLISION does not have to be enabled to use BUMP. See
the COLLISION command.
To evaluate sprite collisions, where a BIT position (0-7) in the
numeric result corresponds to a sprite number (0-7):
BIT position: 7 6 5 4 3 2 1 0
| | | | | | | |
BUMP value in binary: 0 0 0 0 0 1 0 1 = 5 decimal
BUMP(1) returns a value representing sprite-to-sprite collisions.
BUMP(2) returns a value representing sprite-to-data collisions.
X = BUMP(1) Result is X=3 if sprites 0 & 1 collided,
as shown above. (binary 101 = 5 decimal).
Note that more than one collision can be recorded, in which case you
should evaluate a sprite's position using the RSPPOS function to
figure out which sprite collided with what. BUMP is reset to zero
after each use.
BVERIFY -- Compare a binary disk file to an area of memory
BVERIFY "filename" [,Paddress] [,Bbank] [,Ddrive] [<ON|,>Udevice]
BVERIFY compares a binary disk file called "filename" to an area of
memory. In direct mode, if the areas contain the same data the message
"OK" is displayed, and if the data differs the message 'VERIFY ERROR'
is displayed.
In program mode, an error is generated if a mismatch is found
otherwise the program continues normally. The comparison starts with
the address given, else it starts at the address stored on disk. The
comparison ends when the last byte is read from the disk file.
If a bank number is not given, the bank given in the last BANK
statement will be used. The ending address is determined by the
length of the disk file. The comparison halts on the first mismatch or
at the end of the file. The area to be compared must be confined to
the indicated memory bank.
BVERIFY "sprites", P(dec("600")), B0
CATALOG -- see DIR (DIRECTORY) command
CHANGE -- Find text in a BASIC program and change it.
CHANGE :string1: TO :string2: [,line_range]
CHANGE "string1" TO "string2" [,line_range]
This is a direct (edit) mode command. CHANGE looks for all occurrences
of string1 in the program, displays each line containing string1 with
the target string highlighted, and prompts the user for one of the
following:
Y<RETURN> Yes, change it and look for more
N<RETURN> No, don't change it, but look for more
*<RETURN> Yes, change all occurrences from here on
<RETURN> Exit command now, don't change anything
Any character can be used for the string delimiter, but there are side
effects: see comments at FIND command. If the line number range is not
given (see LIST for description of range parameter), the entire
program is searched.
CHAR -- Draw a character string on a graphic screen
CHAR column, row, height, width, direction, "string" [,charsetadr]
[*** THIS IS SUBJECT TO CHANGE ***]
CHAR displays text on a graphic screen at a given location. The
character height, width, and direction are programmable. The
parameters are defined as:
column: Character position:
For 320 wide screens, 0-39
For 640 wide screens, 0-79
row: Pixel line:
For 200 line screens, 0-199
For 400 line screens, 0-399
height: Multiple of 8-bit character height:
1= 8 pixels high, 2= 16 pixels, etc.
width: Multiple of 8-bit character width:
1= 8 pixels high, 2- 16 pixels, etc.
direction: Bit mask: B0= up
B1= right
B2= down
B3= left
The string can consist of any printable character, as defined by the
VIC character set. Non-text characters are ignored. If the address
of the character set is not given, the upper/lower ROM character set
is used ($29800).
The following imbedded control characters are supported:
^F 6 flip
^I 9 invert
^O 15 overwrite
^R 18 reverse field on
146 reverse field off
^U 21 underline
^Y 25 tilt
^Z 26 mirror
When specifying a character set from ROM, note that national versions
of the C64DX will have the national character set at $39000 and the
C64 character set at $3D000. In US/English systems, the default
C64DX-mode character set will be at $39000.
CHAR 18,96, 1,1,2, "C65D", DEC("9000")
The above example will draw the characters "C65D" in the center of a
320x200 pixel screen using the system's uppercase/graphic character
set.
CHR$ -- Character string function
CHR$ (value)
This function returns a string of one character having the PETSCII
value specified. This function is the opposite of the ASC function.
It's often used in PRINT strings to output data that is not visible,
such as control codes and escape sequences. Refer to the Table of
PETSCII Character Codes.
PRINT CHR$(27)"Q"; CHR$(27) is the escape character.
This statement performs the
clear-to-end-of-line escape function.
CIRCLE -- Draw a circle on a graphic screen
CIRCLE x_center, y_center, radius [,solid]
The CIRCLE command will draw a circle with the given radius centered
at (x_center,y_center) on the current graphic screen. The circle will
be filled (i.e., a disc) if SOLID is non-zero.
CIRCLE 160,100,50
The above example will draw a circle in the center of a 320x200 pixel
screen (160,100) having a radius of 50 pixels. The aspect ratio of the
screen may cause it to appear as an ellipse, however. See also the
ELLIPSE command.
CLOSE -- Close a logical I/O channel
CLOSE logical_channel_number
This command closes the input/output channel associated with the given
logical_channel_number, established by an OPEN statement. In the case
of buffered output (such as the serial bus or RS232) any data in the
device's buffer will be transmitted before the channel is closed.
Refer to specific I/O operations for details.
The logical_channel_number is required; to close all channels on a
given device, use the DCLOSE command. Note that RUN, NEW, and CLR
commands will initialize the logical channel tables but will not
actually close any channels.
CLR -- Clear program variables
CLR
This statement initializes BASIC's variable list, setting all numeric
variables to zero and string variables to null. It also initializes
the DATA pointer, BASIC runtime stack pointer (i.e., clears all
GOSUBs, DO/LOOPs, FOR/NEXT loops, etc.), and clears any user functions
(DEF FNx). Any OPEN channels are forgotten (but a CLOSE is not
performed; don't use if there are any open disk output files). A CLeaR
is automatically performed by a RUN or a NEW command.
CLR ERR$ Clears BASIC error stuff, useful after a TRAP
CMD -- Set default output channel
CMD logical_channel_number [,string]
CMD changes the default output device, normally the screen, to that
specified. The logical_channel_number can be any previously OPENed
write channel, such as one to a disk file, printer, or RS232.
When redirected via CMD, all output which normally would go to the
screen (such as PRINT commands, LIST output, DIRECTORY lists, etc.)
is sent to another device or file.
The redirection is terminated by CLOSE-ing the CMD channel or
executing a PRINT# to the CMD channel. Some output devices require a
PRINT# to be performed before the CMD channel is closed, such as
printers, to cause the device's buffer to be flushed (i.e.,
displayed).
Any system error will redirect output back to the system default,
normally the screen, but will not flush nor close the output channel.
If the optional string is given, it is output immediately after the
CMD device is established. This feature is normally used to set up
printers (eg., set printer modes via escape codes) or to identify the
output (eg., title printouts).
OPEN 4,4 OPENS device #4, which is the printer.
CMD 4 All normal output now goes to the printer.
LIST The LISTing goes to the printer.
PRINT#4 Set output back to the screen.
CLOSE 4 Close the printer channel.
COLLECT -- Check (validate) disk, delete bad files and free lost sectors
COLLECT [Ddrive] [<ON|,>Udevice]
Refer to the DOS 'V'alidate command. This command will cause the DOS
to recalculate the Block Availability Map (BAM) of the diskette in the
indicated drive, allocating only those sectors being used by valid,
properly closed files. All other sectors are marked as "free" and
improper files are automatically deleted.
Note: COLLECT should be used with extreme care, and MUST NOT be used
on diskettes with special boot sectors or direct access (eg., random)
files. In any case, be sure the diskette has been BACKUP-ed first.
COLLISION -- Setup subroutine to handle special events
COLLISION type [,linenumber]
[*** THIS MIGHT CHANGE ***]
COLLISION is used to handle "interrupt" situations in BASIC, such as
sprites bumping into things or lightpen triggers. When the specified
situation occurs, BASIC will finish processing the currently executing
instruction and perform an automatic GOSUB to the linenumber given.
When the subroutine terminates (it must end with a RETURN) BASIC will
resume processing where it left off. Interrupt handling continues
until a COLLISION of the same type but without any linenumber is
specified. More than one type interrupt may be enabled at the same
time, but only one interrupt can be handled at a time (i.e., no
recursion and no nesting of interrupts). The type interrupt can be:
1 = Sprite to sprite collision
2 = Sprite to display data collision
3 = Light pen
Note that what caused an interrupt may continue causing interrupts for
some time unless the situation is altered or the interrupt is
disabled. This is especially true for BASIC, which is slow to respond
to interrupts. Use the BUMP and RSPPOS functions to evaluate the
results of sprite collisions, and the LPEN function to evaluate the
position of a light pen.
10 COLLISION 1,90
20 SPRITE 1,1 : MOVSPR 1,100,100 : MOVSPR 1,0#5
30 SPRITE 2,1 : MOVSPR 2,100,150 : MOVSPR 2,180#5
40 DO : PRINT : LOOP
50 END
90 PRINT"BUMP! ";:RETURN
In this example, sprite-to-sprite collisions are enabled (line 10),
and two sprites are turned on, positioned, and made to move (lines
20 & 30). One sprite moves up and the other moves down while the
program does nothing other than print blank lines to the screen (line
40). When the sprite collide, the subroutine at line 90 is called, it
prints "BUMP!", and the computer goes back to printing blank lines.
COLOR -- Enable or disable screen color (character attribute) control
COLOR <ON|OFF>
COLOR turns on or turns off the screen editor's attribute handler.
When colors are turned off, whatever character attributes are being
currently displayed (text color, underline, flash, etc.) are "stuck".
The main purpose for doing this is to speed up screen handling
(writing to the screen or scrolling the screen) about two times, since
the screen editor no longer has to manipulate the attributes. Note
that only FOREGROUND colors (and special VIC attributes) are affected.
To change screen colors, use the following commands:
FOREGROUND color# Set Foreground color (text)
HIGHLIGHT color# Set Highlight color (text)
BACKGROUND color# Set VIC background color
BORDER color# Set VIC border color
CONCAT -- Concatenate (merge) two sequential disk files
CONCAT "file1"[,Ddrive1] TO "file2"[,Ddrive2] [<ON|,>Udevice]
CONCAT merges two SEQuential files, appending the contents of "file1"
to "file2". Upon completion, "file2" contains the data of both files,
and "file1" is unchanged. Both files must exist on drives of the the
same unit, and pattern matching is not allowed.
Some disk drives handle CONCAT differently; refer to the DOS manual
for specific details.
CONT -- Continue program execution
CONT
CONTinue is used to re-start a BASIC program that was halted by a STOP
or END statement, or interrupted by the <STOP> key. The program will
resume at the statement following the STOP or END instruction, or at
the statement after the one that was interrupted by the <STOP> key.
CONT is typically used during program debugging. You can look at and
alter variables while the program is halted.
Programs halted as a result of an untrapped error condition cannot be
CONTinued. Programs that have been edited in any way cannot be
restarted. Any error condition that occurs since the program was
halted will prevent it from being restarted. Programs that cannot be
restarted via CONT can be restarted with a GOTO, as long as you don't
need to resume execution in the middle of a line of commands and you
recall where the halt occurred.
Note that the <STOP> key can interrupt some commands in mid-execution,
such as file I/O, drawing commands, etc. In such cases, programs may
not run correctly after a CONTinue.
COPY -- Copy disk files
COPY ["file1"][,Dd1] TO ["file2"][,Dd2] [<ON|,>Udevice]
COPYs a disk file to another disk file. On single drive units, the
filenames must be different. On dual drive units, copying can be
done between two drives on the same unit, and the filenames can be the
same or different. Pattern matching can be used. Copying files from
one unit to a different unit cannot be done: use a copy utility
program in such cases. Only legal type files can be copied; direct
access data, boot sectors, and partitions cannot be copied.
Refer to the DOS manual for your disk drive specific details.
COPY "file1" TO (F2$) Copies "file1" to another file
whose name is in F2$ on the
same drive. Names must differ.
COPY "file1",D0 TO D1,U9 Copies "file1" from unit 9
drive-0 to unit 9 drive-1.
COPY D0 TO D1 Copies all files from drive-0
to drive-1 on the same unit.
COPY "???.src",D0 TO "*",D1 Copies all files on drive-0
matching the pattern to a file
of the same name on drive-1.
COS -- Cosine function
COS (expression)
This function returns the cosine of X, where X is an angle measured
in radians. The result is in the range -1 to 1.
X = COS (pi) Result is X=-1
To get the cosine of an angle measured in degrees, multiply the
numeric expression by pi/180.
CURSOR -- Place cursor on screen
CURSOR [<ON|OFF>,] [column] [,row] [,style]
column,row = x,y logical screen position
style = flashing (0) or solid (1)
ON,OFF = to turn the cursor on or off
CUT -- Cut a graphic area into a temporary structure
CUT x,y,dx,dy
[*** NOT YET IMPLEMENTED ***]
DATA -- Define program constant data to be accessed by READ command
DATA [list of constants]
DATA statements store lists of data that will be accessed during
program execution by a READ statement. The DATA statement can appear
anywhere in the program, and it is never executed. BASIC keeps a
pointer to the earliest un-READ DATA statement, and data is read
sequentially from first item in a DATA statement to the last item,
from the earliest DATA statement in the program to the last DATA
statement in the program.
The list of constants can contain both numeric data (integer or
floating point) and string data, but cannot contain expressions which
must be evaluated (such as 1+2, DEC("1234"), or CHR$(13)). Items are
separated by commas. String data need not be enclosed in quotes unless
it contains certain characters, such as spaces, commas, colons,
graphic characters, or control codes. If two commands have nothing
between them, the data will be READ as 0 if numeric or a null string.
The RESTORE command allows you to position BASIC's data pointer to a
specific line number. If the program tries to read more DATA than
exists in the program, an 'OUT OF DATA' error results. If a READ
statement's variable type does not agree with the DATA being read, a
'TYPE MISMATCH' error results.
DATA 100, 200, FRED, "HELLO, MOM", , 3.14, ABC123, -1.7E-9
DCLEAR -- Clear all open channels on disk drive
DCLEAR [Ddrive] [<ON|,>Udevice]
DCLEAR sends the indicated disk drive an 'I'nitialize command. This
clears all open channels, closes all open files, and causes the DOS to
re-read the diskette's Block Allocation Map (BAM). Note that DCLEAR
DOES NOT close open channels on the computer's side (see the DCLOSE
command). There are some other side affects caused by this command
with different types of drives -- refer the DOS manual for your disk
drive for specific details.
DCLOSE -- Close a disk file, or close all channels on a device
DCLOSE [#logical_file_number] [<ON|,>Udevice]
DCLOSE is intended to close a file opened with the DOPEN command.
Specific files can be closed by specifying a logical_file_number, or
all files on a particular drive can be closed by not specifying a
particular logical_file_number.
It is possible to close channels on non-disk devices with this command
by specifying only the device number.
DCLOSE#1 Closes the file associated with logical
logical file number 1.
DCLOSE Closes all files currently open on the
default system drive.
DCLOSE U(U2) Closes all channels open to device U2.
DEC -- Decimal value function
DEC (hex_string)
This function return the decimal value of a string representing a
hexadecimal number in the range "0000" to "FFFF". The result is in
the range 0-65535. If the string contains a non-hexadecimal digit or
is more than four (4) characters in length an 'ILLEGAL QUANTITY'
error is reported.
VIC = DEC("D000") Result is VIC=53248,
the address of the VIC chip
DEF FN -- Define function
DEF FN name(numeric_variable) = numeric_expression
Define a user-written numeric function. The DEF FNx statement must be
executed before the function can be used. Once a function has been
defined, it can be used like any other numeric variable. The function
name is the letters FN followed by any legal floating point
(non-integer) variable name. A function can be defined only in a
program.
The numeric_variable is a "dummy" variable. It names the variable the
numeric_expression which will be replaced when the function is used.
It's not required to be used in the numeric_expression, and its value
won't be changed by the function call.
The numeric_expression performs the calculations of the function. It
is any legal numeric expression that fits on one line. Variables used
in the expression have their value at the time the function is used.
Functions can be used only by the program which defines them. If one
program chains to another program, the first program's functions
cannot be used (usually a 'SYNTAX ERROR' results). Similarly, if the
program is moved in any way after the function is defined, the
function cannot be used.
10 DEF FN R(MAX) = INT(RND(0)*MAX)+1
20 INPUT "MAXIMUM"; MAX
30 PRINT FN R(MAX)
In this example, we've defined a function which will return a pseudo
random number between 1 and whatever MAX is. Instead of using the
expression INT(RND(0)*MAX)+1 every time a random number is needed, we
can now use FN R(MAX). When we use FN R(x), the value of 'x' will be
substituted everywhere MAX is used in the function definition.
10 DEF FN I(X) = X+1
20 DEF FN L(Z) = LEN(A$)
30 DEF FN AVG(N) = (TOT*CNT+N)/(CNT+1)
DELETE -- Delete lines of BASIC program, or
Delete disk files
DELETE [startline] [-[endline]]
DELETE "filespec" [,Ddrive] [<ON|,>Udevice] [,R]
There are two forms of DELETE. The first form is used in direct mode
to remove lines from a BASIC program:
DELETE 75 Deletes line 75
DELETE 10-50 Deletes line 10 through 50 inclusive.
DELETE -50 Deletes all lines from the beginning of
the program up to and including line 50.
DELETE 75- Deletes all lines from 75 to the end of
the program.
The second form is used in program or direct mode to delete a disk
file. See the SCRATCH command.
DELETE "myfile" Deletes the file MYFILE on the system drive.
DIM -- Declare array dimensions
DIM variable(subscripts) [,variable(subscripts)]...
Before arrays of variables can be used, the program must first execute
a DIM statement to establish DIMensions of that array (unless there
are 11 or fewer elements in the array). The statement DIM is followed
by the name of the array, which may be any legal variable name. Then,
enclosed in parentheses, put the number (or numeric variable) of
elements in each dimension. An array with more than one dimension is
called a matrix. Any number of dimensions may be used, but keep in
mind that the whole list of variables being created takes up space in
memory, and it is easy to run out of memory if too many are used. To
figure the number of variables created with each DIM, multiply the
total number of elements in each dimension of the array. Note: each
array starts with element 0, and integer arrays take up 2/5ths of the
space of floating point arrays.
More than one array can be dimensioned in a DIM statement by
separating the arrays by commas. If the program executes a DIM
statement for any array more than once, the message 'REDIM'D ARRAY' is
reported. It is good programming practice to place DIM statements
near the beginning of the program.
10 DIM A$(40),B7(15),CC%(4,4,4)
| | |
41 elements 16 elements 125 elements
DIRECTORY -- List the files of a diskette
DIR
DIRECTORY ["filespec"] [,R] [,Ddrive] [<ON|,>Udevice]
A directory is a list of the names of the files that are on a
diskette. The directory listing consists of the name of the diskette,
the names, sizes, and filetypes of all the files on a diskette, and
the remaining free space on the diskette. The filespec is used to
specify a pattern match string to view selected files. Not all disk
drives support the same options or filespecs; refer to your DOS manual
for details. The C64DX allows you to print DIR listings without having
to 'load' the directory; see example below.
The commands DIR, DIRECTORY, and CATALOG have the exact same function.
They can be used in direct or program mode.
DIRECTORY List all files on the diskette
in the default system drive
DIR "*.src", U9 Lists the all the files ending with
".src" on unit 9.
DIR "*,=p",R List all the deleted but recoverable
PRG-type files on the system drive.
OPEN 4,4:CMD 4:DIR:CLOSE 4 Print DIR listing to printer unit 4.
The following program can be used to load the directory into variables
for use within a program. In this case, the filename is simply printed
to the screen:
10 OPEN 1,8,0,"$0:*,P,R" open dir as a file
20 : IF DS THEN PRINT DS$: GOTO 100 abort if error
30 GET#1,X$,X$ trash load address
40 DO read each line
50 : GET#1,X$,X$: IF ST THEN EXIT trash links, check EOF
60 : GET#1,BL$,BH$ get file size
70 : LINE INPUT#1, F$ get filename & type
80 : PRINT LEFT$(F$,18) print filename
90 LOOP loop until EOF
100 CLOSE 1 close dir
DISK -- Send a disk command
DISK "command_string" [<ON|,>Udevice]
The DISK command is used to send special commands to the DOS via the
disk drive's command channel. The DISK command is analogous to the
following BASIC code:
OPEN 1,n,15: PRINT#1,"command_string": CLOSE 1
Not all disk drives understand the same commands. Refer to your DOS
manual for commands and command syntax for your drive. Note that the
drive number, if any, must be included in the command_string.
DISK "U0>10" Renumber system drive to 10.
DISR "U0>V"+chr$[0) Turn off write verify
DISK "S0:file",U(n) Scratch "file" on unit n
DLOAD -- Load a BASIC program file from disk
DLOAD "filename" [,Ddrive] [<ON|,>Udevice]
This command copies a BASIC program from disk into the BASIC program
area of the computer. It can then be edited, DSAVEd, or RUN.
Used in program mode, it overlays the current program in memory and
begin execution automatically at the first line of the new program.
Variable definitions will be left intact, but any open data files and
the disk command channel will be automatically closed. This is called
CHAINING.
See also RUN. Use BLOAD to load binary or machine language data.
DLOAD "myprogram" Searches the default system disk drive
for the BASIC program "myprogram",
loads it, and relinks it.
DLOAD (F$),U9 LOADs a program whose name is in F$
from disk unit 9.
DMA -- Perform a DMA operation
DMA command [,length,source(l/h/b),dest(l/h/b),subcmd,mod(l/h) [,...]]
[*** THIS COMMAND IS SUBJECT TO CHANGE ***]
The DMA command defines and executes a Direct Memory Access operation.
The parameters are used to construct a DMA list, which is then passed
to the DMA processor for execution. Refer to the DMA chip
specification for details. Chained DMA commands are not allowed, but
multiple DMA commands can be given and the DMA handler will set up
and execute each one, one at a time. Refer to the system memory map to
find out where things are.
Because this command directly accesses system memory, extreme care
should be taken in its use. Changing the wrong memory locations can
crash the computer (press the reset button to reboot).
DMA 3, 2000, ASC("+"), 0, DEC("800"), 0 Fill screen with '+'
DMA 0, 2000, DEC("800"), 0, DEC("8000"), 1 Copy screen to $18000
DMODE -- Set graphic display mode
DMODE jam, comp, inverse, stencil, style, thickness
[*** THIS COMMAND IS SUBJECT TO CHANGE ***]
jam 0-1
complement 0-1
inverse 0-1
stencil 0-1
style 0-3
thickness 1-8
DO/LOOP/WHILE/UNTIL/EXIT -- Program loop definition and control
DO [UNTIL boolean_expression | WHILE boolean_expression]
.
. statements [EXIT]
.
LOOP [UNTIL boolean_expression | WHILE boolean_expression]
Performs the statements between the DO statement and the LOOP
statement. If no UNTIL or WHILE modifies either the DO or the LOOP
statement, execution of the intervening statements continues
indefinitely. If an EXIT statement is encountered in the body of a DO
loop, execution is transferred to the first statement following the
nearest LOOP statement. Do loops may be nested, following the rules
defined for FOR-NEXT loops. If the UNTIL parameter is used the program
continues looping until the boolean argument is satisfied (becomes
true). The WHILE parameter is basically the opposite of the UNTIL
parameter: the program continues looping as long as the boolean
argument is TRUE. An example of a boolean argument is A=1, or G>65.
DO UNTIL X=0 or X=1 This loop will continue
: statements until X=0 or X=1. If
LOOP X=0 or 1 at beginning
the loop won't execute.
10 A$="": DO GETKEY A$: LOOP UNTIL A$="Q" This will loop until
the user types 'Q'
10 DOPEN#1,"FILE" This program will
20 C=0 count the number of
30 DO: LINEINPUT#1,A$: C=C+1: LOOP UNTIL ST lines in FILE
40 DCLOSE#1
50 PRINT"FILE CONTAINS";C;" LINES."
DOPEN -- Open a disk file
DOPEN#lf,"filename[,<S|P>]"[,L[reclen]] [,W] [,Ddrive] [<ON|,>Udevice]
This command OPENs a file on disk for reading or writing. If is the
logical file number, which you will use in PRINT#, INPUT#, GET#,
RECORD#, and DCLOSE# commands to reference the channel to your file.
The filename is required. The defaults are to OPEN a SEQuential file
for Reading, in which case the file must exist or a 'FILE NOT FOUND'
error results. To create an file and write to it, use the 'W'rite
option. 'FILE EXISTS' error is report if an output file already
exists. To read or write a RELative file, use the 'L'ength option. The
'reclen' record length is required only when creating a relative file.
For more information regarding Relative files, see the RECORD command
and refer to your DOS manual. See also APPEND.
See the OPEN command for a discussion about channel and device
numbers.
DOPEN#1,"readfile" Opens sequential READFILE for reading.
DOPEN#1,"writefile",W Creates & opens seq WRITEFILE for writing.
DOPEN#1,"file,P",U(u) Opens a PRoGram type file for reading on unit U
DOPEN#1,(rf$),L Open existing relative file whose name's in RF$
DOPEN#a,"rel",L80 Create a relative file with record length of 80
DPAT -- Set graphic draw pattern
DPAT type [, # bytes, byte1, byte2, byte3, byte4]
[*** THIS COMMAND IS SUBJECT TO CHANGE ***]
type 0-63
# bytes 1-4
byte1 0-255
byte2 0-255
byte3 0-255
byte4 0-255
DSAVE -- Save a BASIC program into a disk file
DSAVE "[@]filename" [,Ddrive] [<ON|,>Udevice]
This command copies a BASIC program in the computer's BASIC memory
area into a PRoGram-type disk file. If the file already exists, the
program is NOT stored and the error message 'FILE EXISTS' is reported.
If the filename is preceded with an '@', then if the file exists it
will be replaced by the program in memory. Because of some problems
with the 'save-with-replace' option on older disk drives, using this
option is not recommended if you do not know what disk drive is being
used. Use the DVERIFY to compare the program in memory with a program
on disk.
To save a binary program, use the BSAVE command.
DSAVE "myprogram" Creates the PRG-type file MYPROGRAM
on the default system disk and copies
the BASIC program in memory into it.
DSAVE "@myprogram" Replaces the PRG-type file MYPROGRAM
with a new version of MYPROGRAM. If
MYPROGRAM doesn't exist, it's created.
DSAVE (F$),U9 Saves a program whose name is in F$
on disk unit 9.
DVERIFY -- Compare a program in memory with one on disk
DVERIFY "filename" [,Ddrive] [<ON|,>Udevice]
This command is just like a DLOAD, but instead of LOADing the BASIC
program file into computer memory the data is read from disk and
compared to computer memory. If there's any difference at all a
'VERIFY ERROR' is reported.
Note: If the BASIC program in memory is not located at the same
address as the version on disk was SAVEd from, the files will not
match even if the program is otherwise identical. The comparison ends
when the last byte is read from the disk file.
Use the BVERIFY command to compare memory with binary files.
DVERIFY "myprogram"
Good: SEARCHING FOR 0:myprogram Bad: SEARCHING FOR 0:myprogram
VERIFYING VERIFYING
OK ?VERIFY ERROR
ELLIPSE -- Draw an ellipse on a graphic screen
ELLIPSE x_center, y_center, x_radius, y_radius [,solid]
The ELLIPSE command will draw an ellipse with the given radii centered
at (x_center,y_center) on the current graphic screen. The ellipse will
be filled (i.e., a disc) if SOLID is non-zero.
ELLIPSE 160,100,65,50
The above example will draw an ellipse in the center of a 320x200
pixel screen (160,100) having radii of (65,50) pixels. The aspect
ratio of the screen may cause it to appear as an circle, however. See
also the CIRCLE command.
ELSE -- See IF/THEN/ELSE
END -- Define the end of program execution
END
The END statement terminates program execution. It does not close
channels or files, and it does not clear any variables or reset any
pointers. An END statement does not need to be put at the last line of
a program.
The CONTinue command can be used to resume execution with the next
statement following the END statement. See also the STOP command.
ENVELOPE -- Define musical instrument envelopes
ENVELOPE n, [,[atk] [,[dec] [,[sus] [,[rel] [,[wf] [,pw] ]]]]]
n............... Envelope number (0-9)
atk ............ Attack rate (0-15)
dec ............ Decay rate (0-15)
sus ............ Sustain rate (0-15)
rel ............ Release rate (0-15)
wf ............. Waveform: 0 = triangle
1 = sawtooth
2 = pulse (square)
3 = noise
4 = ring modulation
pw ............. Pulse width (0-4095)
[*** THIS COMMAND IS SUBJECT TO CHANGE ***]
A parameter that is not specified will retain its current value. Pulse
width applies to pulse waves (wf=2) only and is determined by the
formula (pwout = pw/40.95 %), so that pw = 2048 produces a square wave
and values of 0 or 4095 produce constant DC output. The C64DX
initializes the ten (10) tune envelopes to:
n A D S R wf pw instrument
------------------ -------------
ENVELOPE 0, 0, 9, 0, 0, 2, 1536 piano
ENVELOPE 1,12, 0,12, 0, 1 accordion
ENVELOPE 2, 0, 0,15, 0, 0 calliope
ENVELOPE 3, 0, 5, 5, 0, 3 drum
ENVELOPE 4, 9, 4, 4, 0, 0 flute
ENVELOPE 5, 0, 9, 2, 1, 1 guitar
ENVELOPE 6, 0, 9, 0, 0, 2, 512 harpsichord
ENVELOPE 7, 0, 9, 9, 0, 2, 2048 organ
ENVELOPE 8, 8, 9, 4, 1, 2, 512 trumpet
ENVELOPE 9, 0, 9, 0, 0, 0 xylophone
ERASE -- Delete disk files
ERASE "filespec" [,Ddrive] [<ON|,>Udevice] [,R]
This command is identical to DELETE and SCRATCH. See the SCRATCH
command for details.
ERASE "myfile" Deletes the file MYFILE on the system drive.
ERR$ -- Error message function
ERR$ (error_number)
This function returns a string which is the BASIC error message
corresponding to the given error_message. If the given number is too
small (less than 1) or too large (greater than 41) an 'ILLEGAL
QUANTITY' error is reported.
This function is usually used to display a BASIC error condition in a
TRAP routine, using the BASIC error word ER as the error_number.
Note that when ER=-1, no BASIC error has occurred and ERR$(-1) results
in an 'ILLEGAL QUANTITY' error.
See the example at TRAP.
EXIT -- See DO/LOOP/WHILE/UNTIL/EXIT
EXP -- Function to return e^x
EXP (number)
This function returns the numeric value of e (2.71828183), the base of
natural logarithms) raised to the power of given number. If the
number is greater than 88.0296919 an 'OVERFLOW' error is reported.
X = EXP(4) Result is X=54.5981501
FAST -- Set system speed to 3.58MHz
FAST is the default state of the system. FAST is used to restore this
state following direct access of "slow" I/O devices such as the SID
sound chips.
FETCH -- (see the DMA command)
FILTER -- Define sound filter parameters
FILTER [freq] [,[lp] [,[bp] [,[hp] [,res] ]]]
freq ..... Filter cut-off frequency (0-2047)
lp ....... Low pass filter on (1) off (0)
bp ....... Band pass filter on (1), off(0)
hp ....... High pass filter on (1), off(0)
res ...... Resonance (0-15)
[*** THIS COMMAND IS SUBJECT TO CHANGE ***]
Unspecified parameters result in no change to the current value. The
filter output modes are additive. For example, how low pass and
high pass filters can be selected to produce a notch (or band reject)
filter response. For the filter to have an audible effect at least
one filter output mode must be selected and at least one voice must be
routed through the filter.
FIND -- Find text in a BASIC program.
FIND :string: [,line_range]
FIND "string" [,line_range]
This is a direct (edit) mode command. FIND looks for all occurrences
of string in the program and displays each line containing string,
with string highlighted. Use the <C=> key to slow the display, or the
<NO-SCROLL> key to pause the display. Press <STOP> to cancel.
Any character can be used for the string delimiter, but there are side
effects. Using a non-quote delimiter will cause the string to be
tokenized, and FIND will find only tokenized strings in the program
that match. Using a quote character as the delimiter will cause the
string to be interpreted as plain PETSCII, and any matches found will
therefore be plain PETSCII. Searching for some tokens such as DATA
statements may require the use of colons as delimiters due to the
special affect these commands have upon the interpreter.
If the line number range is not given (see LIST for description of
range parameter), the entire program is searched.
FN xx -- User defined function
FN xx (expression)
The result of this numeric function is determined by the BASIC program
in a DEF FN statement. See the example at DEF FN.
FOR/TO/STEP/NEXT -- Program loop definition and control
FOR index = start TO end [STEP increment]
|
NEXT index [,index]
This command group performs a series of instructions a given number of
times. The loop index is a floating point (non-integer) variable
which will initially be set to the start value and be incremented by
the STEP increment when the NEXT statement is encountered. The loop
continues until the index exceeds the end value at the NEXT statement.
The start, end, and increment values can be numeric variables or
expressions. If the STEP increment is not specified, it is assumed to
be one (1). The STEP increment can be any value, positive, negative,
or non-integer. If the STEP increment is negative, the loop continues
until the index is less than the end value at the NEXT statement.
Note that, regardless of the start, end, or increment values, the loop
will always execute at least once. The index can be modified within
the loop, but it is bad practice to do so. It is also bad practice to
GOTO a line inside a loop structure, or to similarly jump out of a
loop structure (which can cause an 'OUT OF MEMORY' error).
Loops may be nested. If too many are nested, an 'OUT OF MEMORY' error
is reported (depends upon stack size, room for about 28 nested loops).
The index variable can be omitted from the NEXT statement, in which
case the NEXT will apply to the most recent FOR statement. If a NEXT
statement is encountered and there is no preceding FOR statement, the
error 'NEXT WITHOUT FOR' is reported.
10 FOR L = 1 TO 10
20 PRINT L
30 NEXT L
40 PRINT "I'M DONE! L = "L
This program prints the numbers from one to ten, followed by the
message I'M DONE! L = 11.
10 FOR L = 1 TO 100
20 FOR A = 5 TO 11 STEP .5
30 NEXT A
40 NEXT L
This program illustrates a nested loop.
FOREGROUND -- Set the text color of the display
FOREGROUND color
Sets the text color to the given color index. Color must be in the
range (0-15). See the Color Table. COLOR must be ON (see the COLOR
command).
FRE -- Free byte function
FRE (x)
This function returns the number of available ("free") bytes in a
specified area.
PRINT FRE(0) Shows the amount of memory left in the program area,
C64DX bank 0
X = FRE(1) X= the amount of available memory in variable area
C64DX bank 1. This causes a "garbage collect" to
occur, a process which compacts the string area.
X = FRE(2) X= the number of expansion RAM banks present.
GCOPY -- Copy a graphic area
[*** NOT YET IMPLEMENTED ***]
GENLOCK -- Enable or disable video sync mode & colors
GENLOCK ON [,color#]...
GENLOCK OFF [,color#,R,G,B]...
To enable video sync mode and specify which colors are affected, use
the GENLOCK ON command, and list the palette color indices (0-255)
which will display external video.
To disable video sync mode and restore the associated palette colors
use the GENLOCK OFF command, and list the color index and its RGB
values to restore them (see the SET PALETTE command for details). Also
see the PALETTE RESTORE command.
GET -- Get input data from the keyboard
GET variable_list
The GET statement is a way to get data from the keyboard one character
at a time. When the GET is executed, the character that was typed is
received. If no character was typed, then a null (empty) character is
returned, and the program continues without waiting for a key. There
is no need to hit the <RETURN> key, and in fact the <RETURN> key can
be received with a GET. The word GET is followed by a variable name,
usually a string variable. If a numeric were used and any key other
than a number was hit, the program would stop with an error message.
The GET statement may also be put into a loop, checking for an empty
result, that waits for a key to be struck to continue. The GETKEY
statement could also be used in this case. This statement can only be
executed within a program.
10 DO: GET A$: LOOP UNTIL A$ ="A"
This line waits for the A key to be pressed to continue.
GETKEY -- Get input character from keyboard (wait for key)
GETKEY variable_list
The GETKEY statement is very similar to the GET statement. Unlike the
GET statement, GETKEY waits for the user to type a character on the
keyboard. This lets it be used easily to wait for a single character
to be typed. This statement can only be executed within a program.
10 GETKEY A$
This line waits for a key to be struck. Typing any key will continue
the program.
GET# -- Get input data from a channel (file)
GET# logical_channel_number, variable_list
Used with a previously OPENed device or file to input one character at
a time. Otherwise, it works like the GET statement. This statement can
only executed within a program.
10 GET#1,A$
GO64 -- Exit C64DX mode and switch to C64 mode
GO64
This statement switches from C64DX mode to C64 mode. The question 'ARE
YOU SURE?' (in direct mode only) is posted for the user to respond to.
If Y and return is typed then the currently loaded program is lost and
control is given to C64 mode. This statement can be used in direct
mode or within a program.
GOSUB -- Call a BASIC subroutine
GOSUB line
This statement is like the GOTO statement, except that the computer
remembers from where it came. When a line with a RETURN statement is
encountered, the program jumps back to the statement immediately
following the GOSUB. The target of a GOSUB statement is called a
subroutine. A subroutine is useful if there is a section of the
program that can be used by several different parts of the program.
Instead of duplicating the section over and over, it can be set up as
a subroutine and called with a GOSUB statement from different parts of
the program. This also make the main part of your program much more
readable. See also the RETURN statement.
Variables are shared with the main program and all subroutines. You
can pass information to, and get information back from, subroutines
by using variables as messengers.
GOSUB statements can be nested. That is, one subroutine can call
another subroutine, and the computer automatically keeps track of
all the calls. It's important not to jump into or out of subroutines
since this can confuse the computer. If too many GOSUBs are nested
(usually cause by jumping out of them) an 'OUT OF MEMORY' error is
reported because the computer ran out of room to keep track of all
the calls.
10 DIR : GOSUB 100 show directory, check status
20 GOSUB 200 print gap
30 LIST "PROGRAM": GOSUB 100 show listing, check status
40 GOSUB 200 print gap
50 etc...
90 END
99 :
100 REM SUBROUTINE TO CHECK DISK STATUS
110 IF DS THEN GOSUB 200: PRINT "DISK ERROR: ";DS$
120 RETURN
199 :
200 REM SUBROUTINE TO PRINT A SPACER ON THE SCREEN
210 PRINT
220 FOR I=1 TO 39: PRINT"-";: NEXT
230 PRINT
240 RETURN
GOTO -- Transfer program execution to specified line number
GOTO line_number
GO TO line_number
After a GOTO statement is executed, the next line to be executed will
be the one with the line number following the word GOTO. When used in
direct mode, GOTO line number allows starting of execution of the
program at the given line number without clearing the variables.
10 PRINT"COMMODORE"
20 GOTO 10
The GOTO in line 20 makes line 10 repeat continuously until STOP is
pressed.
GRAPHIC -- select graphic mode
GRAPHIC CLR
GRAPHIC command# [,args]
Basically this is a modified C64-type SYS command, minus the address.
In the C64DX system, this will represent the ML interface, not the
BASIC 10.0 interface which is implemented in the development system.
[*** THIS COMMAND IS SUBJECT TO CHANGE ***]
GRAPHIC CLR initializes (warm-starts) the BASIC graphic system. It
clears any existing graphic modes, screens, etc. and allows a program
to commence graphic operations from scratch.
HEADER -- Format a diskette
HEADER "diskname" [,Iid] [,Ddrive] [<ON|,>Udevice]
The HEADER command prepares a new diskette for use, sometimes called
FORMATting a diskette. There are two types of "newing" a diskette -- a
long form and a quick (or short) form. You must use the long form when
preparing a new diskette for its first use. Thereafter you can use the
quick form.
WARNING: Formatting a diskette (long or short) will destroy all
existing data on the diskette! In direct mode, you are asked to
confirm what you are doing with 'ARE YOU SURE?'. Type 'Y' and press
return to proceed, or TYPE ANY OTHER CHARACTER AND PRESS RETURN TO
CANCEL the command. In program mode there is no confirmation prompt.
The long HEADER form requires a diskname and an ID. The diskette will
be completely (re)sectored, zeros written to all blocks, and a new
system track (directory, BAM, etc.) will be created.
HEADER "newdisk",I01 prepares a new diskette
The short HEADER form is performed when the ID option is omitted. The
diskette is assumed to have been previously formatted, and only a new
system track (directory, BAM, etc.) is installed. This is roughly
equivalent to deleteing all the files, but much quicker.
HEADER "makelikenew" re-news an working diskette
The diskname is limited to 16 characters and the ID string to two
characters. The same rules apply for the diskname as for a filename.
Some Disk Systems use the ID string to tell if you have swapped a
diskette in a drive, so it's recommended that the ID string be unique
for each of your diskettes. Some more examples:
HEADER "QUICK"
HEADER "MYDISK", I23
HEADER "RECS", I"FB", U9
HEADER (FILES), I(ID$), U(UNIT)
HELP -- Show the BASIC line that cause the last error
HELP
The HELP command is used after an error has been reported in a
program. When HELP is typed, the line where the error occurred
listed, with the portion containing the error highlighted. Print
ERR$(ER) for the error message, and print EN or EL for the error
number and error line, respectively. HELP can be used in direct mode
or in program mode. Note that, in the case of many I/O errors, there
is no associated BASIC error. Check ST or DS$ errors in these cases.
HEX$ -- Hexadecimal value function
HEX$ (decimal_expression)
This function returns a 4-character string that represents the
hexadecimal value of the numeric decimal expression. The expression
must be in the range (0-65535, $0000-$FFFF hex) or an 'ILLEGAL
QUANTITY' error is reported.
PRINT HEX$(10) The string "000A" is printed.
PRINT RIGHT$(HEX$(10),2) The string "0A" is printed.
HIGHLIGHT -- Set the text highlight color of the display
HIGHLIGHT color
Sets the highlight color to the given color index. The color value
must be in the range (0-15). See the Color Table. COLOR must be ON
(see the COLOR command). The highlight color is used in HELP messages
and FIND/CHANGE strings.
IF/THEN/GOTO/ELSE -- Conditional program execution
IF expression <GOTO line | THEN then_clause> [:ELSE else_clause]
IF...THEN lets the computer analyze a BASIC expression preceded by IF
and take one of two possible courses of action. If the expression is
true, the statement following THEN is executed. This expression can be
any BASIC statement. If the expression is false, the program goes
directly to the next line, unless an ELSE clause is present. The ELSE
clause, if present, must be in the same line as the IF-THEN part. When
an ELSE clause is present, it is executed when the THEN clause isn't
executed. In other words, the ELSE clause executes when the expression
is FALSE. See BEGIN/BEND to spread the IF statement out over several
lines. An ELSE statement is matched to the closest THEN statement in
the case of nested IF/THEN statements.
The expression being evaluated may be a variable or formula, in which
case it is considered true if nonzero, and false if zero. Usually
expressions involve relational operators =, <, >, <=, >=, <>.
50 IF X>0 THEN PRINT "X>0": ELSE PRINT "X<=0"
If X is greater than 0, the THEN clause is executed, and the ELSE
clause isn't. If X is less than or equal to 0, the ELSE clause is
executed and the THEN clause isn't.
INPUT -- Get input from the keyboard
[LINE] INPUT ["prompt"<,l;>] variable_list
The INPUT statement pauses the BASIC program, prints the prompt string
if present, prints a question mark and a space, and waits for data to
be typed by the user, terminated by a return character. If the prompt
string ends with a comma instead of a semicolon, a question mark and
space is not printed.
Input is gathered and assigned to variables in the variable_list. The
type of variable must match the type of input typed or a 'TYPE
MISMATCH' error is reported. Separate data items typed by the user
must be separated with commas. String data with imbedded spaces or
commas must be surrounded with quotes. If insufficent data to satisfy
the variable-list is typed, two question marks are displayed by the
computer to prompt for additional data to be input. If the computer
does not understand the input (such as the user typing cursor up or
down keys) the computer responds with the message 'REDO FROM START?'
and waits for acceptable data to be entered. Input is limited to 160
characters (two screen lines in 80-column mode), which is the size of
the input buffer.
The INPUT statement can only be executed from within a program.
LINE INPUT allows the program to input a string which includes any
PETSCII character (including colons, commas, imbedded spaces, etc.)
up to but not including a null or return character. There should be
only one string-type variable name in the variable_list in this case,
but if there are more the computer prompts as usual with two question
marks for more data to assign to the additional variables.
10 INPUT "WHAT'S YOUR FIRST NAME AND AGE"; NA$,A
20 PRINT "YOUR NAME IS ";NAS;" AND YOU ARE";A;" YEARS OLD"
The above INPUT is the traditional BASIC form.
10 LINE INPUT "WHAT'S YOUR ADDRESS"; AD$
20 PRINT "YOUR ADDRESS IS: ";AD$
The above INPUT allows an entire line of data to be assigned to a
string variable, including commas and other common punctuation marks.
10 INPUT "ENTER YOUR NAME HERE: ", NA$
The above INPUT suppresses the traditional '? ' prompt by using a
comma instead of a semicolon after the prompt string. To suppress the
'?' without a prompt string, make the prompt string null.
INPUT# -- Input data from an I/O channel (file)
[LINE] INPUT#logical_channel_number, variable_list
The INPUT# command works like the INPUT command, except no prompt
string is allowed and input is gathered from a previously OPENed
channel or file. This command can only be used in a program.
The logical channel number is the number assigned to the device (file)
in an OPEN (or DOPEN) statement. Items in the variable list must agree
with the type of data input, or a 'FILE DATA ERROR' will resuit.
On the C64DX, an End Of File (EOF) condition or bad I/O status will
terminate input, as if a return character was received. It's good
practice to examine the I/O status byte (and the DS disk status for
file I/O) after every I/O instruction to check for problems or errors.
10 DOPEN#1, "FILE" This program will
20 C=0 count the number of
30 DO: LINE INPUT#1,AS: C=C+1: LOOP UNTIL ST lines in FILE
40 DCLOSE#1
50 PRINT"FILE CONTAINS";C;" LINES."
INSTR -- Get the location of one string inside another string
INSTR (string_1, string_2 [,starting_position])
This function searches for the first occurrence of string_2 in
string_1 and returns its location. A value of zero (0) is returned if
no match is found, if either string is null (empty), or if string_2
is longer than string_1.
If the starting position is given, the search begins at that location,
otherwise the search begins at the first character of string_1.
The strings can be literals, variables, or string expressions.
X = INSTR("123456","4") Result is X= 0
X = INSTR("123456","X") Result is X= -1
X = INSTR("123123","2") Result is X= 123
X = INSTR("123123","2",3) Result is X=-124
INT -- Greatest integer function
INT (expression)
This function returns the greatest integer less than or equal to the
numeric expression.
JOY -- Joystick function
JOY (port)
This function returns the state of a joystick controller in the
specified port.
When port=l returns position of joystick 1
When port=2 returns position of joystick 2
The value returned is encoded as follows:
Fire = 128 + 1
8 2
7 0 3
6 4
5
A value of zero (0) means that the joystick is not being manipulated.
A value of 128 or more means that the fire button is being pressed.
The possible vales returned are:
0 No activity 128 fire
1 up 129 fire + up
2 up + right 130 fire + up + right
3 right 131 fire + right
4 right + down 132 fire + right + down
5 down 133 fire + down
6 down + left 134 fire + down + left
7 left 135 fire + left
8 left + up 136 fire + left + up
KEY -- Enable, disable, display, or define function keys
KEY ON
KEY OFF
KEY [key#, string]
There are 14 function keys available on the C64DX (seven unshifted and
seven shifted). The user can assign a string consisting of BASIC
commands, control codes, escape functions, or a combination of each to
function key. The data assigned to a key is typed out when that key is
pressed, just as if the characters were typed one by one on the
keyboard. The user can enable ("turn on") or disable ("turn off") the
function keys. When they are disabled, pressing a function key return
that key's normal character code instead of the string assigned to it.
This includes the HELP and (shifted) RUN keys. It is also possible to
redefine the HELP and (shifted) RUN keys, as function keys 15 and 16,
respectively. The system has default assignments for all function
keys. KEY with no parameters displays a listing of the current
assignments for all the function keys.
The maximum length for all the definitions together is 240 characters.
If an assignment would be too big to fit, an 'OUT OF MEMORY' error is
reported and the assignment is not made.
KEY 2, "DIR U9"+CHR$(13)
This causes the computer to display the directory from disk unit #9
when function key 2 is pressed. This is equivalent to typing 'DIR U9'
and pressing the <RETURN> key directly. The CHR$(13) is the character
for <RETURN>. Other often used control codes are CHR$(141) for
'shifted RETURN', CHR$(27) for 'ESCape', and CHR$(34) to incorporate a
double quote into a KEY string.
KEY 2, "DIR"+CHR$(34)+"*=P"+CHR$(34)+CHR$(13)
This is equivalent to typing DIR"*=P" and pressing <RETURN> at the
keyboard. Note the way quotes can be incorporated into an
assignment. When function key 2 is pressed, a directory of all program
files on the default system disk will be displayed.
KEY OFF
This turns off function key strings. Pressing a function key now would
return the character codes associated with F-keys as on the VIC-20 and
C64 computers. KEY ON would re-enable function key strings, unchanged
from their previous assignments. To restore the system default
assignments, reset the computer.
LEFT$ -- Get the leftmost characters of a string
LEFT$ (string,count)
This function returns a string containing the leftmost 'count' number
of characters of the string expression. Count is an numeric
expression in the range (0-255). If count is greater than the length
of the string, the entire string will be returned. If count is zero,
a null (empty) string will be returned.
A$ = LEFT$("123ABC",3) Result is A$="123"
LEN -- Get the length of a string
LEN (string)
This function returns the number of characters in a string expression.
Nonprinting characters and blanks are counted.
A = LEN("ABC") Result is A=3
LET -- Assign a value to a variable
[LET] variable = expression
The LET command is optional, since the equal sign by itself is
understood by the computer to mean assignment. Multiple assignments
on LET statements are not allowed.
10 LET A=1: LET B=A+1: LET C$=" THREE"
20 : D=1: E=D+1: F$=" THREE"
30 PRINT A;B;C$
40 PRINT D;E;F$
Output: 1 2 THREE
1 2 THREE
LINE -- Draw a line on a graphic screen
LINE x0, y0 [,[x1] [,y1]]...
LINE draws a line on the currently defined graphic screen with the
currently defined draw modes. The line is draw from (x0,y0) to
(x1,y1), if more parameters are specified a line is drawn from point
to point. If only x0 and y0 are specified, draws a dot.
LIST -- List a BASIC program from memory or disk
LIST [startline] [- [endline] ]
LIST "filename" [,Ddrive] [<,|ON>Udevice]
LIST is used to view part or all of a BASIC program in memory or all
of a BASIC program on disk (without affecting the program that is
currently in memory).
The display can be slowed down by holding down the <C=> key or it can
be paused by pressing the <NO-SCROLL> key or <CONTROL><S>. A listing
that is paused can be restarted by pressing <NO-SCROLL> again or by
pressing <CONTROL><Q>. The display can be stopped by pressing <STOP>.
If the word LIST is followed by a line number, the computer shows only
that line number. If LIST is typed with two numbers separated by a
dash, the computer shows all lines from the first to the second line
number. If LIST is typed followed by a number and just a dash, it
shows all lines from that number to the end of the program. And if
LIST is typed, a dash, and then a number, all lines from the beginning
of the program to that line number are LISTed. By using these
variations, any portion of a program can be examined or easily brought
to the screen for modification. LIST can be used in direct mode or in
a BASIC program.
LIST Shows entire program.
LIST 100- Shows from line 100 until the end of the program.
LIST 10 Shows only line 10.
LIST -100 Shows lines from the beginning until line 100.
LIST 10-200 Shows lines from 10 to 200, inclusive.
LOAD -- Load a program or data into memory from disk
LOAD "filename" [,device_number [,relocate_flag]]
This command loads a file into the computer's memory. The filename
must be given, and pattern matching may be used. In the case of dual
drive systems, the drive number must be part of the filename. If a
device number is given, the file is sought on that unit, which must be
a disk drive. If a device number is not given, the default system
drive is used. See also DLOAD and RUN commands.
The relocate_flag is used to LOAD binary files. If the relocate_flag
is present and non-zero, the file will be copied into memory starting
at the address stored on disk when the file was SAVEd. See BLOAD. Do
not use the relocate_flag to load BASIC programs: they will be
automatically relocated to the start of the BASIC program area and
relinked.
To compare a program in memory to a disk file, use the VERIFY or
DVERIFY command. To compare a binary file, use BVERIFY.
See the discussion at DLOAD regarding CHAINING programs.
LOAD "PROG" Loads BASIC program PROG from the system drive.
LOAD FILE$,DRV Loads a program whose name is in the variable
called F$ from the unit whose number is in DRV.
LOAD "0:PROG" 8 Loads BASIC program PROG from unit 8, drive 0.
LOAD "BIN",8,1 Loads a binary file into memory.
LOADIFF -- Load an IFF picture from disk.
LOADIFF "file" [,U#,D#]
Loads an IFF picture from disk. Requires a suitable graphic screen to
be already opened (this may change). The file must contain std IFF
data in PRG file type. IFF pics can be ported directly from Amiga
(eg., using XMODEM). Returns 'File Data Error' if it finds data it
does not like.
LOCATE -- [*** NOT YET IMPLEMENTED ***]
LOG -- Get the natural logarithm of a number
LOG (number)
This function returns the natural logarithm of a numeric expression. A
natural log is a log to the base e (2.71828183). See the EXP function.
To convert to log base 10, divide by LOG(10).
A = LOG(123) Result is A=4.81218436
A = LOG(123) / LOG(10) Result is A=2.08990511
LOOP -- See DO/LOOP/WHILE/UNTIL/EXIT
LPEN -- Get the position of a lightpen
PEN (position)
This function returns the current position of a lightpen on the
screen. When position=0, the X position is returned, and when
position=1 the Y position is returned. Note that lightpen coordinates,
like sprite coordinates, are offset from the normal graphic coordinate
map. This means you have to calculate where the lightpen is with
respect to the screen display. The electronics of each lightpen also
introduces a skew which must be factored into your calculations.
The X resolution is limited to every 2 pixels, and will always be an
even number in the approximate range (60-320). The Y position is in
the approximate range (50-250). If either the X or the Y position is
zero, the lightpen is off-screen.
Note that a lightpen COLLISION need not be enabled to use LPEN. A
bright background color, such as white, is usually required to
stimulate the light pen. Lightpens only work in game port 1.
10 TRAP 40 We're done if STOP key
15 BACKGROUND 1 Make background color white
16 FOREGROUND 0 Make text color black
20 COLLISION 3,100 Enable lightpen interrupt
30 DO:LOOP Hang here until done
40 END Done
100 COLLISION 3 Got one, don't want more
110 PRINT LPEN(0),LPEN(1) Display lightpen position
120 COLLISION 3,100 Re-enable interrupt
130 RETURN
MID$ -- Substring function
MID$ (string, position [,length])
This function can appear on the left or the right side of an
assignment statement:
Case 1: string_var = MID$ (string_expression, position [,length])
This form returns a piece of another string. The function returns a
string of the specified length taken from the string_expression
beginning at the indicated position. The position must be in the range
(1-255), one (1) being the first character. The length can be any
number in the range (0-255), or it can be omitted. If the position
specified is greater than the number of characters in the
string_expression, a null (empty) string is returned. If the length is
greater than the number of characters from the given position to the
end of the string_expression, or the length is omitted, then all the
rightmost characters beginning at the position are returned.
A$ = MID$("TICTACTOE",4,3) Result is A$="TAC"
A$ = MID$("TICTACTOE",4) Result is A$="TACTOE"
A$ = MID$("TICTACTOE",10,1) Result is AS="" (empty)
Case 2: MID$ (string_var, position [,length]) = string_expression
This form replaces a portion of the string contained in string_var
with data from another string_expression, beginning at the specified
position in the string_var. If the length is given only, that many
characters from the string_expression are taken, otherwise all the
characters in the string_expression will replace characters in the
string_var beginning at the position specified. The there are too many
characters to fit in the string_var, an 'ILLEGAL QUANTITY' error is
reported. If the length given is zero, no characters will be replaced.
A$="TICTACTOE": MID$(A$,4,3)="123456" Result is A$="TIC123TOE"
A$="TICTACTOE": MID$(A$,4) ="123456" Result is A$="TIC123456"
A$="TICTACTOE": MID$(A$,5) ="123456" Result is 'ILLEGAL QUANTITY'
MOD -- Function to calculate modulus
MOD (number, modulus)
New function. (*TODO*: write documentation)
MONITOR -- Enter the built-in machine language monitor
SEE SECTION 3.2 ON THE C64DX MONITOR.
MOUSE -- Enable or disable the mouse driver
MOUSE ON [,port [,sprite [,position] ] ]
MOUSE OFF
port = joyport 1, 2, or either (both) (1-3)
sprite = sprite pointer (0-7)
position = initial pointer location (x,y)
normal, relative, or angular coordinate
defaults to sprite 0, port 2
???? add min/max x/y positions
[*** THIS COMMAND IS SUBJECT TO CHANGE ***]
Mouse ON enables the built-in mouse driver. The user must load a
pointer into the proper sprite area ($600-$7FF). The driver assumes
the "hot point" is the top left corner of the sprite, and does not
allow this point to leave the screen.
Mouse OFF will turn off the driver and the currently associated
sprite.
Use the RMOUSE function to get the current pointer position and button
status. See the sample program at RMOUSE.
*TODO*: include update:
MOUSE ON [,[port] [,[sprite] [,[hotspot] [,X/Yposition] ]]]
MOUSE OFF
where: port = (1...3) for joyport 1, 2, or either (both)
sprite = (0...7) sprite pointer
hotspot = x,y offset in sprite, default 0,0
position = normal, relative, or angluar coordinates
Defaults to sprite 0, port 2, last hotspot (0,0), and
position. Kernel doesn't let hotspot leave the screen.
MOVSPR -- Position sprite or set sprite in motion
MOVSPR sprite <,x,y>
Use the SPRITE command to turn on a sprite and MOVSPR to position it.
Sprites are numbered 0-7. The sprite's position can be specified using
one of the following coordinate types:
[+/-]x, [+/-]y = [relative] position
x#y = angle and speed
x;y = distance and angle
Angles are specified as 0-360 degrees, with 0 being straight up.
Speeds are specified as a number of pixels per frame, 0-255. Sprites
are moved through each pixel so that collisions are accurately
detected.
NEW -- Delete program in memory and clear all variables
NEW [RESTORE]
This command erases the entire program in memory and clears all
variables and open channels (but it does NOT properly close open
disk write files -- used DCLOSE or DCLEAR beforehand). NEW also resets
the runtime stack pointer (clears GOSUB & FOR/NEXT stacks), the DATA
pointer, and the PRINTUSING characters.
The BASIC program in memory is lost unless it was previously SAVEd to
disk. If you have not entered or loaded any BASIC programs since
typing NEW, the RESTORE option will recover the BASIC program in
memory. But if the BASIC environment has been changed in any way, the
program may not be restored correctly. If BASIC can tell something's
wrong, it will report 'PROGRAM MANGLED'.
NEW can be used in direct (edit) mode or in a program. When it's
encountered in a program, the program terminates.
NEXT -- See FOR/NEXT/STEP and RESUME
NOT -- Get the complement of a number
NOT (expression)
The NOT function returns the complement of an integer in the range
(-32768 to 32767). The function operates on the binary value of signed
16-bit integers. An expression outside of this range will cause an
'ILLEGAL QUAUTITY' error.
X = NOT(5) Result is X=-6
X = NOT(-6) Result is X=5
NOT is often used in logical comparisons (such as an IF statement) to
invert the result, since -1 (true) is the result of NOT(0) (false),
and 0 (false) is the result of NOT(-1) (true).
X = NOT("ABC"="ABC") AND ("DEF"="DEF") Result is X= 0 (false)
X = NOT("ABC"="ABC") AND ("DEF"="XYZ") Result is X=-1 (true)
OFF -- Subcommand used with various BASIC commands.
ON -- Computed GOTO/GOSUB
ON expression <GOTO|GOSUB> line_number_list
This is a variation of the IF <expression> GOTO statement that
branches to one of several line numbers based upon the value of an
expression. The integer value of the evaluated expression determines
which line number in the line_number_list gets control.
If the expression evaluates to one, the first line number in the list
gets control, if it's two the second line number gets control, and so
on. Fractional parts of the value are truncated (for example, 2.9
becomes 2). If the value is zero or greater than the number of items
in the list the computer takes none of the branches and continues on
with the next statement. If the value is negative, an 'ILLEGAL
QUANTITY ERROR' is reported.
The ON/GOSUB statement must call the first line number of a subroutine
and the subroutine must end with a RETURN statement. After executing
the subroutine, control is returned to the statement following the
ON/GOSUB statement.
10 INPUT"ENTER A NUMBER 1-3: ",X
20 ON X GOTO 100, 200, 300
30 PRINT"TOO LOW OR TOO HIGH": RUN
100 PRINT"ONE": RUN
200 PRINT"TWO": RUN
300 PRINT"THREE": RUN
OPEN -- Open a channel to a device or disk file
OPEN logical_chnl_num, device_number [,secondary_adr
[,<filespec|command>]]
Before a program can access a device or a file, an I/O channel must be
opened to it to communicate through. When something is opened, you
associate a logical channel number with it, and it is with this number
that all other I/O statements access the device or file. The OPEN
command can be used in direct (edit) mode or in a program.
The channel number, device number, and optional secondary address are
integers from 0-255. Refer to the device's manual for more
information about what (if any) secondary addresses it uses.
channel: 0-127 return = output return character only
128-255 return = output return + linefeed
device: 0 Keyboard
1 Default system drive
whatever its number is (see SET DEF)
2 RS232
3 Screen
4-7 Serial bus
(usually reserved for printers)
8-31 Serial bus
(usually reserved for disk drives)
The filespec is the file name in the case of disk files (refer to your
DOS manual for details). Typically, the filename is a string having
the the following form:
[[@|S]drive:] filename [,type] [,mode]
An example would be 0:MYFILE,SEQ,READ to open the sequential file
MYFILE for reading on drive 0. Disk drives usually support some kind
of filename pattern matching. Most disk drives support the following
file types and modes (can be abbreviated to first character):
types: 'S'equential
'P'rogram
'R'elative
'U'ser
modes: 'R'ead
'W'rite
'L'ength (for relative type files)
Some channels or devices accept a command string instead of a filename
when they are opened. An example would be the disk command channel or
the RS232 open/setup command. Refer to the device's documentation.
OPEN 1,8,15,"I" Open CBM disk command channel & send
it the 'I'nitialize command.
OPEN 4,4,7 Open CBM printer channel in upper/lower
case mode.
OPEN 128,2,2,CHR$(14) Open a 9600 8N1 RS232 channel and
translate CR into CRLF on output.
See also DOPEN, DCLOSE, CLOSE, CMD, GET#, INPUT#, and PRINT#
statements and I/O status variables ST, DS, and DS$.
OR -- Boolean operator
expression OR expression
The OR operator returns a numeric value equal to the logical OR of two
numeric expressions, operating on the binary value of signed 16-bit
integers in the range (-32768 to 32767). Numbers outside this range
result in an 'ILLEGAL QUANTITY' error.
X = 4 OR 8 Result is X=12
In the case of logical comparisons, the numeric value of a true
situation is -1 (equivalent to 65535 or $FFFF hex) and the numeric
value of a false situation is zero.
X = ("ABC"="ABC") OR ("DEF"="DEF") Result is X=-l (true)
X = ("ABC"="ABC") OR ("DEF"="XYZ") Result is X=-1 (true)
X = ("ABC"="XYZ") OR ("DEF"="XYZ") Result is X= 0 (false)
PAINT -- Fill a graphics area with color
PAINT x,y, mode [,color]
x,y coordinate to begin fill at
mode 0: fill area to edge = color
1: fill area to edge=same as color at x,y
PAINT fills an enclosed graphic area starting at the given coordinate
with the color of the currently defined PEN. The mode parameter
identifies the region to be filled.
[*** THIS COMMAND IS NOT YET IMPLEMENTED ***]
*TODO*: include update
PAINT x, y [,color]
Working, but not completely to spec. Uses draw pen
color and fills emptyness to any border.
PALETTE -- Define a color
PALETTE [screen#|COLOR], color#, red, green, blue
PALETTE RESTORE
screen# 0-1
color# 0-255
red 0-15
green 0-15
blue 0-15
The PALETTE command can be used to define a color for a logical
graphic screen, set an absolute color, or restore the C64DX VIC-III
default colors. PALETTE can be used in direct mode or in a program.
The VIC-III pre-defines the first 16 colors to the usual C64-type
colors, but you can change them with the PALETTE COLOR command or
restore them all with the PALETTE RESTORE command.
See the sample program after the SCREEN command.
PASTE -- Put a CUT graphic area on the screen
PASTE x,y
[*** NOT YET IMPLEMENTED ***]
PEEK -- Function returning the contents of a memory location
PEEK (address)
This function returns the contents of a memory location. The address
must be an integer in the range of 0-65535 ($0-$FFFF) and the value
returned will be an integer in the range of 0-255 ($0-$FF).
Use the BANK command to specify which 64K memory bank the address is
in. Note that a BANK number greater than 127 (i.e., a bank number
with the most significant bit set) must be used to address an I/O
location, such as the VIC chip or color memory. Refer to the system
memory map for details. PEEK uses the DMA device to access memory.
Use the POKE command to change the contents of a memory location.
BANK 0: X = PEEK (208) Reads the keyboard buffer index. If
it's empty, X will be zero, otherwise X
will be the number of characters in it.
PEN -- Specify a pen color for drawing on graphic screen
PEN pen, color
pen 0-2
color 0-255
Before you can draw anything on a graphic screen, you have to tell
BASIC what color your PENs are. You should first define what your
colors are using the PALETTE command, then use PEN to associate those
colors with a PEN. Whatever graphic commands you use after a PEN
command will use the PEN you specified.
PEN 0,1 Put color 1 "ink" into draw pen 0
See the sample program after the SCREEN command.
PIC -- Graphic picture subcommand
PLAY -- Play a musical string
PLAY "[Vn,On,Tn,Un,Xn,elements]"
[*** WILL CHANGE TO ADD 2ND SID SUPPORT ***]
The PLAY command lets you select a voice, octave, instrument, volume,
filter, and musical notes. All these parameters are packed into a
string (spaces are allowed for readability).
On = Octave (n=0-6)
Tn = Tune envelope # (n=0-9)
0= piano (defaults)
1= accordion
2= calliope
3= drum
4= flute
5= guitar
6= harpsichord
7= organ
8= trumpet
9= xylophone
Un = Volume (n=0-9)
Vn = Voice (n=1-3)
Xn = filter on (n=1), off (n=0)
Elements:
A,B,C,D,E,F,G ... Notes, may be preceded by:
# ................. Sharp
S ................. Flat
. ................. Dotted
W ................. Whole note
H ................. Half note
Q ................. Quarter note
I ................. Eighth note
S ................. Sixteenth note
R ................. Rest
M ................. Wait for all voices playing to end
(a measure)
Once the music string starts PLAYing, the computer will continue with
the next statement. The music will continue to play automatically.
Using the 'M'easure command will cause the computer to wait until the
music has up to that point has been played out.
Use the TEMPO command to alter the tempo (speed) of PLAY. Note that
the VOLume command can change a PLAY string's volume setting.
POINTER -- Get the address of a variable descriptor
POINTER (variable_name)
This function returns the address of an entry in the variable table.
If the value returned is zero, the variable is currently undefined.
The variable table is normally in the second RAM bank (BANK 1). See
the section on variable storage for details.
Note that, while the location of a string descriptor will not change,
the location of the actual string in memory changes all the time.
Also, when working with an array name you must specify a particular
element, to which POINTER will return a pointer to that element's
descriptor and not to the array descriptor.
10 A$="FRED" Define A$
20 DESC=POINTER (A$) Lookup A$ in variable table
30 BANK1: PRINT PEEK(DESC) Displays the length of A$
PORE -- Write a byte to memory location
POKE address, byte [,byte ...]
POKE is used to write one or more bytes into one or more memory
locations. The address must be an integer in the range of 0-65535
($0-SFFFF) and the value to be written must be an integer in the range
of 0-255 ($0-$FF). If more than one byte is given, it will be written
into successive memory locations.
Use the BANK command to specify which 64K memory bank the address is
in. Note that a BANK number greater than 127 (i.e., a bank number
with the most significant bit set) must be used to address an I/O
location, such as the VIC chip or color memory. Refer to the system
memory map for details. Also note that, unlike previous CBM computers,
POKEs to a ROM location will not "bleed through" into a corresponding
RAM location. POKE uses the DMA device to access memory.
Use the PEEK function to read a byte from a memory location.
Because this command directly accesses system memory, extreme care
should be taken in its use. Altering the wrong memory location can
crash the computer (press the reset button to reboot).
BANK 0: POKE 208,0 Resets location 208 ($000D0),
clearing the keyboard buffer.
BANK 128: POKE DEC("D023"),1,2,3 Sets the VIC extended background
colors to 1, 2, and 3 respectively
POLYGON -- Draw a regular n-sided figure on a graphic screen
POLYGON x,y, xradius,yradius, [solid], angle,drawsides,sides,subtend
x,y = center of polygon
x,yradius = radii of polygon
solid = solid flag (0-1)
angle = starting angle (0-360)
drawsides = # of sides to draw (3-127)
sides = # sides of polygon (drawsides<=sides)
subtend = subtend flag (0-1)
POS -- Get the column number of the cursor
POS(0)
This function returns the current text column the cursor is in, with
respect to the currently defined window (see RWINDOW). It's usually
used to format text printed to the screen. The argument (0) is not
used for anything. POS will not work as expected if text output is
redirected to a disk file or the printer.
10 MAXCOL = RWINDOW(l)
20 FOR ADR=DEC("600") TO DEC("7FF")
30 PRINT HEX$(PEEK(ADR));" ";
40 IF POS(0) > (MAXC0L-5) THEN PRINT
50 NEXT
This example illustrates one way to format output to the screen,
keeping the last item on a line from being split between two lines,
regardless of the window size (as long as the window size is at least
4 characters wide). It dumps the data for the first sprite in hex.
POT -- Paddle function
POT (paddle)
This function returns the state of a game paddle (POTentiometer)
controller in one of the two game ports.
paddle=1 ..... Position of paddle #1 (port 1, paddle "A")
paddle=2 ..... Position of paddle #2 (port 1, paddle "B")
paddle=3 ..... Position of paddle #3 (port 2, paddle "A")
paddle=4 ..... Position of paddle #4 (port 2, paddle "B")
The value returned by POT ranges from 0 to 255. Any value greater than
255 means that the fire button is also pressed. Paddles are read
"backwards" from normal things like volume knobs or faucets. A value
of 255 means the paddle has been turned counterclockwise as far as it
will go ("off"), and a value of 0 means the paddle has been turned
clockwise as far as it will go "on").
Note that some paddles are "noisy" and their output must be averaged
or "damped" to prevent whatever they are controlling from jittering.
10 SPRITE 1,1 Turn on a sprite
20 DO Begin a loop
30 X=POT(3) Read paddle "A" in port 2
40 MOVSPR 1,300-(X AND 254),200 Move the sprite
50 LOOP UNTIL X>255 Loop until button pressed
60 SPRITE 1,0 Turn off sprite
This sample program turns on a sprite and lets you move it
horizontally with a paddle. If you press the paddle's fire button, it
turns off the sprite and the program ends. The calculations in line 40
do several things all at once -- they mask the fire button and "damp"
the output to reduce jitter by masking the least significant bit (the
X AND 254 part) and invert the output so that turning the paddle to
the right makes the sprite go right (subtracting result from 300).
PRINT -- Display data on text screen
PRINT [expression_list] [<,|;>]
PRINT will evaluate each item in the expression_list and pass the
results to the system screen editor to display on the screen. If a
screen window is defined, the output will be confined to the window.
PRINT can be used to send control codes and escape sequences to the
screen editor to do such things as set windows, change TAB stops,
change text colors or set reverse field, or choose cursor styles. See
the section on Editor modes for details.
PRINT can be followed by any of the following:
Numeric or string expressions 12, "HELLO", 1+1, "S"+STR$(I)
Variable names A, B, A$, X$
Functions ABS(33), HEX$(160)
Punctuation marks ;,
Nothing
Numeric values are always followed by a space. Positive numbers are
preceded by a space, and negative numbers are preceded by a minus sign
('-'). Scientific notation is used when a number is less than 0.01 or
greater than or equal to 999999999.2 .
A semicolon (';') or space between list items causes the next item to
be printed immediately following the previous item. A comma (',')
causes the next item to be printed at the next comma stop (similar to
TAB stops, but every 10 spaces). These rules apply to the next print
statement, if the expression_list ends with either a semicolon or a
comma, otherwise a return is printed. Note that floating point
variable names should not be separated from the next variable name
with a space, and constants should not be preceeded or followed by a
space.
For formatted PRINT output, see the PRINT USING command.
PRINT "HELLO" HELLO
A$="THERE": PRINT "HELLO ";A$ HELLO THERE
A=4:B=2: PRINT A+B 6
J=41: PRINT J;: PRINT J-1 41 40
C=A+B:D=B-A: PRINT A;B;C;D 4 2 6 -2
C=A+B:D=B-A: PRINT A,B,C,D 4 2 6 -2
A=1:B=2:AB=3: PRINT A B 3
PRINT 1 2 3, 1 2 3 +1 123 124
PRINT 0.009, 0.01 9E-03 .01
PRINT 999999999; 999999999.2 999999999 1E+09
The CMD command can be used to redirect PRINT output to a device or
file. Also see the POS, SPC, TAB functions, CHAR and PRINT USING.
PRINT# -- Send data to an I/O channel (file)
PRINT#logical_channel_number [,expression_list] [<,|;>]
This command is used to send (transmit) data to a device or file. The
logical_channel number is the number assigned to the device (file)
in an OPEN (or DOPEN) statement. The output is otherwise identical to
that of a PRINT statement, including the comma and semicolon
conventions. Note that certain screen-oriented functions, such as TAB
and SPC do not have the same effect as they do with screen I/O.
It's good practice to examine the I/O status byte (and the DS disk
status for file I/O) after every I/O instruction to check for problems
or errors.
For formatted output, use the PRINT# USING command.
10 OPEN 1,8,15 Initialize disk drive
20 PRINT#1,"I" (same as DCLEAR)
30 CLOSE 1
10 DOPEN#1,"NEWFILE",W Create a SEQ file
20 FOR I=1 TO 10
30 PRINT#1, I, STR$(I) Write numbers 1-10 to it
40 NEXT
50 DCLOSE#1
10 OPEN 2,2,2,CHR$(12) Open 1200 baud RS232 channel
20 PRINT#2, "ATDT,5551212" Send modem a Hayes dial command
PRINT USING -- Output formatted data to the screen, device, or file
PRINT [#logical_channel_number,] USING format; expression_list [<,|:>]
Read about the PRINT and PRINT# commands first for information
regarding the syntax of the expression list and, for device output,
establishing the logical_channel_number.
The items in the expression list must be separated by commas (',').
The format is defined in a string literal or string variable and is
described below. See the PUDEF command for specifing special
formatting characters. The various formatting characters are:
CHARACTER SYMBOL NUMERIC STRING
---------------- ------ ------- ------
Pound sign # X X
Plus sign + X
Minus sign - X
Decimal Point . X
Comma , X
Dollar Sign $ X
Four Carets ^^^^ X
Equal Sign = X
Greater Than Sign > X
The pound sign ('#') reserves room for a single character in the
output field. If the data item contains more characters than the
number of pound signs in the format field, the entire field will be
filled with asterisks ('*').
10 PRINT USING "####";X
For these values of X, this format displays:
A = 12.34 12
A = 567.89 568
A = 123456 ****
For a STRING item, the string data is truncated at the bounds of the
field. Only as many characters are printed as there are pound signs
in the format item. Truncation occurs on the right.
The plus ('+') and minus ('-') signs can be used in either the first
or last position of a format field but not both. The plus sign is
printed if the number is positive. The minus sign is printed if the
number is negative.
If a minus sign is used and the number is positive, a blank is printed
in the character position indicated by the minus sign.
If neither a plus sign nor a minus sign is used in the format field
for a numeric data item, a minus sign is printed before the first
digit or dollar symbol if the number is negative and no sign is
printed if the number is positive. This means that one more character
is printed if the number is positive. If there are too many digits to
fit into the field specified by the pound sign and +/- signs, then an
overflow occurs and the field is filled with asterisks ('*').
A decimal point ('.') symbol designates the position of the decimal
point in the number. There can be only one decimal point in any format
field. If a decimal point is not specified in the format field, the
number is rounded to the nearest integer and printed without any
decimal places.
When a decimal point is specified, the number of digits preceding the
decimal point (including the minus sign, if the number is negative)
must not exceed the number of pound signs before the decimal point. If
there are too many digits an overflow occurs and the field is filled
with asterisks ('*').
A comma (',') allows placing of commas in numeric fields. The position
of the comma in the format list indicates where the commas appears in
a printed number. Only commas within a number are printed. Unused
commas to the left of the first digit appear as the filler character.
At least one pound sign must precede the first comma in a field.
If commas are specified in a field and the number is negative, then a
minus sign is printed as the first character even if the character
position is specified as a comma.
FIELD EXPRESSION RESULT COMMENT
------ ----------- ------ -----------------------------
##.# -.1 -0.1 Leading zero added
##.# 1 1.0 Trailing zero added
#### -100.5 -101 Rounded to no decimal places
###. 10 10. Decimal point added
#$## 1 $1 Leading dollar sign
#### -1000 **** Overflow because 4 digits and
minus sign don't fit in field
A dollar sign ('$') symbol shows that a dollar sign will be printed in
the number. If the dollar sign is to float (always be placed before
the number), specify at least one pound sign before the dollar sign.
If a dollar sign is specified without a leading pound sign, the dollar
sign is printed in the position shown in the format field. If commas
and/or a plus or minus sign is specified in a format field with a
dollar sign, the program prints a comma or sign before the dollar
sign. The four up arrows or carets symbol is used to specify that the
the number is to be printed in E format (scientific notation). A pound
sign must be used in addition to the four up arrows to specify the
field width. The arrows can appear either before or after the pound
sign in the format field. Four carats must be specified when a number
is to be printed in E format. If more than one but fewer than four
carats are specified, a syntax error results. If more than four carats
are specified only the first four are used. The fifth carat is
interpreted as a no text symbol. An equal sign ('=') is used to
center a string in a field. The field width is specified by the number
of characters (pound sign and =) in the format field. If the string
contains fewer characters than the field width, the string is centered
in the field. If the string contains more characters that can be fit
into the field, then the rightmost characters are truncated and the
string fills the entire field. A greater than sign ('>') is used to
right justify a string in a field.
5 X=32: Y=100.23: A$="TEST"
10 PRINT USING "$##.## ";13.25,X,Y
20 PRINT USING "###>#";"CBM",A$
When this is RUN, the following output appears on the screen:
$13.25 $32.00 $*****
CBM TEST
$***** is printed instead of Y because Y has 5 digits, which exceeds
the format specification. The second line asks for the strings to be
right justified, which they are.
PUDEF -- Redefine PRINT USING symbols
PUDEF definition_string
PUDEF allows redefinition of up to 4 symbols in the PRINT USING
statement. Blanks, commas, decimal points, and dollar signs can be
changed into some other character by placing the new character in the
correct position in the PUDEF definition_string.
Position 1 is the filler character. The default is a space character.
Place another character here to be used instead of spaces. Similarly,
Position 2 is the comma character. Default is a comma.
Position 3 is the decimal point.
Position 4 is the dollar sign.
10 PUDEF "*" PRINTs * in the place of blanks.
20 PUDEF " @" PRINTs @ in place of commas.
QUIT -- [*** UNIMPLEMENTED ***]
RCLR -- Get the current screen color
RCLR(source)
[*** CURRENTLY UNIMPLEMENTED ***]
This function returns the color assigned to source as an number in the
range of 0-15. The color sources are:
0 = background
1 = foreground
2 = multicolor 1
3 = multicolor 2
4 = border
5 = highlight color
RDOT -- Get the current position or color of the pixel cursor
RDOT(source)
[*** CURRENTLY UNIMPLEMENTED ***]
This function returns information about the current pixel location.
0 = current X position
1 = current Y position
READ -- Read data from DATA statements
READ variable_list
READ statements are used along with DATA statements. READ statements
read data from DATA statements into variables, just like an INPUT
statement reads data typed by the user. READ statements can be used in
direct or program mode, but DATA statements must be in a program.
The variable types in the variable_list must match the type of DATA
being read, or a 'TYPE MISMATCH' error is reported. If there are
insufficient data in the program's DATA statements to satisfy all
of the variables in the READ statement, an 'OUT OF DATA' error is
reported.
The computer maintains a pointer to the next DATA item to be read by a
READ statement. Initially this pointer points to the beginning of
the program. As each variable in a READ statement is filled, the
computer moves the DATA pointer to the next DATA item. If all of a
READ statement's variables are filled before all of the data has been
read from a DATA statement, the next READ statement will begin reading
data at the point where the previous READ stopped.
The DATA pointer can be changed by the RESTORE command. It can be
reset back to the beginning of the program, or pointed to a specific
line number. See RESTORE.
10 DATA 100, 200, FRED, "HELLO, MOM", , 3.14, ABC123, -1.7E-9
20 READ X,Y
30 READ NAME$, MSG$, NULL$
40 READ PI, JUNK$, S
50 RESTORE
RECORD -- Specify a relative disk file record number
RECORD #logical_channel_number, record [,byte]
This command allows you to access any part of any record in a RELative
type disk file. If the byte parameter is omitted, the access pointer
is pointed at the first byte of the specified record number.
Before you can use RECORD, you must OPEN a file. See OPEN and DOPEN
for instructions. Also refer to your DOS manual for an explanation of
RELative type files.
10 INPUT"ENTER RELATIVE FILENAME: ",F$ get name of existing file
20 DOPEN#1, (F$),L: PRINT DS$ open it & display disk status
30 R=1: INPUT"ENTER RECORD NUMBER: ",R get a record number
40 B=1: INPUT"ENTER BYTE (RETURN): ",B get byte number, if any
50 RECORD#1, R,B position file pointer
60 INPUT#1, REC$ read the record
70 PRINT REC$ display the record
80 PRINT "CONTINUE? (Y/N)"
90 GETKEY A$: IF A$="Y" THEN 30
100 DCLOSE#1 close the file
REM -- Place an explanatory remark or comment in a program
REM plain text message
The REMark command is just a way to leave a note to whomever is
reading a LISTing of the program. It might explain a section of the
program, give information about the author, etc.
REM statements in no way effect the operation of the program, except
to add length to it (and therefore slow it down a little). No other
executable statement can follow a REMark on the same line.
10 REM THIS PROGRAM WAS WRITTEN ON 2/14/91 BY F.BOWEN
20 REM SAMPLE PROGRAM
30 :
40 DIR :REM DISPLAY THE DISK DIRECTORY
50 LIST "SAMPLE PROGRAM" :REM DISPLAY THIS PROGRAM
60 END
RENAME -- Rename a disk file
RENAME "oldname" TO "newname" [,Ddrive] [<ON|,>Udevice]
The RENAME command changes the name of a file in the disk directory.
Pattern matching is not allowed, and "newname" must be a valid
filename that does not already exist on the disk. The file being
renamed does not need to be open.
RENAME "TEST" TO "FINALTEST"
RENAME (OLD$) TO (OLD$+".OLD") ON U(DEV)
RENUMBER -- Renumber the lines of a BASIC program
RENUMBER [new_starting_line [,[increment] [,old_starting_line]]]
Renumber is used to resequence the line numbers of a BASIC program in
memory. All or part of a program can be renumbered. The RENUMBER
command first scans the program to make sure all the line numbers
referenced in commands (such as GOTO, GOSUB, TRAP, etc.) exist, that
new line numbers are in the legal range, and that changing the program
would not overflow the available memory. An 'UNRESOLVED REFERENCE',
'LINE NUMBER TOO LARGE', or 'OUT OF MEMORY' error is reported if
there's a problem, and RENUMBER is automatically canceled without
having changed anything.
If the program passes all the checks, RENUMBER changes the specified
line numbers and updates all references to the old numbers throughout
the program and relinks the program.
The new_starting_line is the number of the first line in the program
after renumbering. It defaults to 10. The increment is the spacing
between line numbers (eg., 10, 20, 30 would mean an increment of 10).
It also defaults to 10. The old_starting_line is the line number in
the program where you want renumbering to begin.
RENUMBER can be used in direct (edit) mode only. Note that line number
zero (0) is a valid line number.
RENUMBER Renumbers the entire program. After
renumbering, the first line will be 10
the second 20, etc. through the end
of the program.
RENUMBER ,1 Renumbers the entire program as above,
but in increments of one. The first
line will be 10, the second 11, etc.
RENUMBER 100, 5, 80 Starting at line 80, renumbers the
program. Line 80 becomes line 100,
and lines after that are numbered in
increments of 5, through the end of
the program.
RENUMBER ,,65 Starting at line 65, renumbers lines
in increments of 10, starting at line
10 through the rest of the program.
RESTORE -- Position READ pointer at specific DATA statement
RESTORE [line]
The computer maintains a pointer to the next DATA item to be read by a
READ statement. Initially this pointer points to the beginning of
the program. The DATA pointer can be changed by the RESTORE command.
Using RESTORE without specifying a line number will reset the DATA
pointer back to the beginning of the program. If a line number is
specified, the DATA pointer is pointed to that line. The line does not
have to contain a DATA statement. When the computer executes the
next READ statement, it will look for the next DATA item starting at
the line the DATA pointer is at.
See the READ command an example.
RESUME - Resume program execution after error TRAP
RESUME [line|NEXT]
Used to return to execution after TRAPping an error. If a line number
is given, the computer performs a 'GOTO line' and resumes execution at
that line. RESUME NEXT resumes execution at the statement following
the one that cause the error. RESUME without any parameters will
resume execution at the statement that cause the error.
If the computer encounters a RESUME statement outside of a TRAP
routine or if a TRAP was not in effect a 'CAN'T RESUME' error is
reported. RESUME can only be used in program mode.
10 TRAP 90
20 FOR I=-5 TO 5
30 PRINT 5/I
40 NEXT
50 END
60 :
90 PRINT ERR$(ER): RESUME NEXT
RETURN -- Return from subroutine or event handler
RETURN
This statement is associated with the GOSUB (GO SUBroutine) statement.
When a subroutine is called by a GOSUB statement, the computer
remembers where it's at before it calls the subroutine. When the
computer encounters a RETURN statement, it returns to the place it
last encountered a GOSUB and continues with the next statement.
If there wasn't a previous GOSUB, then a 'RETURN WITHOUT GOSUB' error
is reported.
RETURN is also used by event handlers, set up by the COLLISION
command. See COLLISION.
RGR -- Get the current graphic mode
RGR(0)
[*** CURRENTLY UNIMPLEMENTED ***]
This function returns current graphic mode. A result of zero means the
display is text, a non-zero result means it's graphic.
RIGHT$ -- Get the rightmost characters of a string
RIGHT$ (string,count)
This function returns a string containing the rightmost 'count' number
of characters of the string expression. Count is an numeric expression
in the range (0-255). If count is greater than the length of the
string, the entire string will be returned. If count is zero, a null
(empty) string will be returned.
A$ = RIGHT$("123ABC",3) Result is A$="ABC"
RMOUSE -- Get the mouse position and button status
RMOUSE [Xposition [,Yposition [,button]]]
X,Yposition = current position of mouse pointer sprite
Button = current status of mouse buttons
0 = no button
1 = right button
128 = left button
129 = both buttons
RMOUSE is a command which retrieves a mouse's current position and the
state of its buttons, and places this information into the specified
numeric variables. If a mouse is not installed, "-1" is returned for
all variables. If both ports are enabled, buttons from each port are
merged. Use the MOUSE command to turn a mouse on or off.
10 MOUSE ON, 2, 1 Turn mouse on, port 2, sprite 1
20 DO Begin loop
30 RMOUSE X, Y, B Get mouse position & buttons
40 PRINTUSING"### ";X,Y,B Show " " "
50 LOOP UNTIL B=129 Loop until user presses both buttons
60 MOUSE OFF Turn mouse off
RND -- Get a pseudo-random number
RND (type)
The RND function returns a pseudo RaNDom number between 0 and 1. The
random sequence returned is determined by the type parameter:
type = 0 Returns a random number based upon the unused POT of the
second SID chip. PCB must allow lines to float.
type < 0 Negative numbers "seed" the random number generator,
defining a new but reproducible random sequence.
type > 0 Positive numbers draw the next random number from the
sequence defined by the last "seed" value.
This lets a programmer use a reproducible sequence while debugging
(fixing) a program, so that random errors can be easily reproduced.
Once the program has been fixed, it can be "seeded" such that a random
sequence is used every time the program is run.
10 DO
20 INPUT "SEED"; S
30 IF S=0 THEN END
40 FOR I=1 TO S
50 PRINT INT(RND(1)*6)+1, INT(RND(1)*6)+1
60 NEXT
70 LOOP
The above program will demonstrate the results of seeding the random
number generator. It lets you specify a positive or negative seed
value, and then prints the first S random pairs of that sequence.
Enter a zero to end the program. The calculations in line 50 make the
random numbers be integers from 1 to 6, like dice. Type in a negative
dice from that sequence. Every time you enter "-1", for example, you
will roll the same numbers:
first roll 2 and 6
second 6 and 1
third 1 and 1
fourth 1 and 4
fifth 5 and 5
Games and statistical programs should use RND(0) for true randomness
or seed the generator with a random number, such as RND(-TI).
The general form for getting random integers using RND is:
INT( RND(0) * MAX ) + 1
where MAX is the highest number you can get. This gives you numbers as
low as 1 and as high as MAX. For dice, MAX is 6 (or 12 if you want
to simulate rolling two dice at once). For cards, MAX is 52.
INT( RND(0) * 16)
This form will return integers from zero to 15, which is useful for
generating random colour values, for example.
RREG -- Get register data after a SYS call
RREG [a_reg] [,[x_reg] [,[y_reg] [,[z_reg] [,status] ]]]
Following a SYS call, the RREG command retrieves the contents of the
microprocessor's registers and puts them into the specified numeric
variables. See the sample program at SYS.
RSPCOLOR -- Get multicolor sprite colors
RSPCOLOR (multicolor#)
Returns the current colors for multicolor sprites. Color values range
from 0-15. Use RSPRITE function to get the foreground sprite color.
multicolor# = 1 gets multicolor #1
multicolor# = 2 gets multicolor #2
See SPRITE and SPRCOLOR.
RSPPOS -- Get the location and speed of a sprite
RSPPOS (sprite,parameter)
The RSPPOS function returns the current X or Y position of a sprite
and its speed, set by the MOVSPR command. A sprite does not have to
be on to use RSPPOS. The sprite number must be in the range of 0-7,
and the parameter is:
0 to get current X position
1 to get current Y position
2 to get current speed (0-255)
RSPRITE -- Get information about a sprite
RSPRITE (sprite,parameter)
The RSPRITE function returns the current state of a sprite, set by the
SPRITE command. The sprite number must be in the range of 0-7, and the
parameter is:
0 to see if it's turned on (1)=yes (0)=no
1 to get sprite foreground color (0-15)
2 to get priority over background (1)=yes (0)=no
3 to get X-expansion factor (1)=yes (0)=no
4 to get Y-expansion factor (1)=yes (0)=no
5 to get multicolor factor (1)=yes (0)=no
RUN -- execute BASIC program
RUN [line #]
RUN "filename" [,Ddrive] [<On|,>Udevice]
RUN executes the BASIC program that is currently in memory. The
program has to be LOADed (DLOAD) or manually typed in before it can
be executed. If a line number is specified, execution begins at that
line. If a filename is specified, the program is automatically loaded
from disk into memory and executed. RUN can be used in a program.
RUN clears all variables and open channels (but it does NOT properly
close open disk write files -- used DCLOSE or DCLEAR beforehand). RUN
also resets the runtime stack pointer (clears GOSUB & FOR/NEXT stacks)
the DATA pointer, and the PRINT USING characters. To start a program
without initializing everything, use GOTO.
RUN Starts the program at the first line.
RUN 100 Starts the program at line 100.
RUN "TEST" Loads the program TEST from the, default system
disk and starts the program at the first line.
RWINDOW -- Get information about the current text window
RWINDOW (parameter)
This is a function that returns information about the current console
text display. The parameter is specified as:
0 to get the maximum line # in the current window
1 to get the maximum column # in the current window
2 to get the screen size, either 40 or 80 columns
SAVE -- Save a BASIC program in memory to disk
SAVE "[[@]drive:]filename" [,device_number]
This command copies a BASIC program in the computer's BASIC memory
area into a PRoGram-type disk file. If the file already exists, the
program is NOT stored and the error message 'FILE EXISTS' is reported.
If the filename is preceded with an '@0:', then if the file exists it
will be replaced by the program in memory. Because of some problems
with the 'save-with-replace' option on older disk drives, using this
option is not recommended if you do not know what disk drive is being
used (DELETE the file before SAVEing). Pattern matching is not
allowed. In the case of dual drive systems, the drive number must be
part of the filename.
Use the VERIFY or DVERIFY command to compare the program in memory
with a program on disk. To save a binary program, use the BSAVE
command.
SAVE "myprogram" Creates the PRG-type file MYPROGRAM
on the default system disk and copies
the BASIC program in memory into it.
SAVE "@0:myprogram" Replaces the PRG-type file MYPROGRAM
with a new version of MYPROGRAM. If
MYPROGRAM doesn't exist, it's created.
SAVE F$,9 Saves a program whose name is in F$
on disk unit 9.
SCALE -- Set the logical dimension of the graphic screen
[*** NOT YET IMPLEMENTED ***]
SCNCLR -- Clear a text or graphic screen
SCNCLR [color]
This command will clear the current text window if [color] omitted,
otherwise it will clear the current graphic screen using the given
color value. See also SCREEN CLR.
SCNCLR Clears the text screen. If a window is defined
it clears only the window area.
SCNCLR 0 Clears the current graphic screen with color 0.
SCRATCH -- Delete files from disk directory
Recover accidentally deleted files
SCRATCH "filespec" [,Ddrive] [<ON|,>Udevice] [,R]
SCRATCH, ERASE, or DELETE are different names of the same command.
They are used to delete a file from a disk directory, or optionally to
recover if possible an accidentally deleted file. The diskette must
not be 'write protected', or a 'WRITE PROTECT ON' error is reported.
WARNING: Deleting a file will destroy all existing data in that file.
Be extremely careful if you are using pattern matching, which can
delete any or all files. In direct mode, you are asked to confirm what
you are doing with 'ARE YOU SURE?'. Type 'Y' and press <RETURN> to
proceed, or type any OTHER CHARACTER and press <RETURN> to cancel the
command. In program mode there is no confirmation prompt.
Upon completion, in direct mode only, the computer will display the
number of files deleted.
Refer to your disk manual for other details. Different disk drives
implement slightly different pattern matching rules or support
features such a specially protected files.
If the 'R'ecover option is present and the DOS supports it, a deleted
file can be recovered if nothing else has been written to the diskette
since the file was accidentally deleted. You will still be asked to
confirm the operation, and upon completion the computer will display
the number of files restored.
SCRATCH "oldfile" Deletes the file OLDFILE from the disk
in the default system drive.
SCRATCH "file.*" Deletes all files beginning with FILE.
SCRATCH (F$), U(DD) Deletes the file whose name is in F$
from the disk in device DD.
SCRATCH "SAVEME", R Attempt to recover the program SAVEME.
SCREEN -- Graphic command
The SCREEN command is used to initiate a graphic command. It always
precedes another command word which identifies the graphic operation
to be performed:
SCREEN CLR - Set graphic screen color
SCREEN CLR color#
Clears (erases) the currently opened graphic screen using the given
color value. Use SCNCLR to clear a text screen. See also SCNCLR.
SCREEN DEF - Define a graphic screen
SCREEN DEF screen#, width, height, depth
screen# 0-1
width 0=320, 1=640, 2=1280
height 0=200, 1=400
depth 1-8 bitplanes (2-256 colors)
Defines a logical screen (numbered 0 or 1), specifies its size and how
many colors (bitplanes) it has. It does not allow access to the
screen and it does not display the screen. The screen must be defined
before it is opened for viewing and/or drawing to.
SCREEN SET - Set draw and view screens
SCREEN SET DrawScreen#, ViewScreen#
draw screen # 0-1
view screen # 0-1
This command specifies which logical screen is to be viewed and which
logical screen is to be accessed by the various draw commands. The
screen must be defined and opened first. Both the draw and the view
screen can be, and usually are, the same logical screen. For double
buffering, they are different.
SCREEN OPEN - Open a screen for access
SCREEN OPEN screen# [,error_variable]
screen# 0-1
error_variable [*** NOT YET IMPLEMENTED ***]
This command actually sets up the screen and allocates the necessary
memory for it. If it's the view screen it will be displayed. If it's
the draw screen, it can now be drawn to. If there is not enough memory
for the screen, 'NO GRAPHICS AREA' is reported and the screen is not
opened.
SCREEN CLOSE - Close a screen
SCREEN CLOSE screen#
screen# 0-1
This command closes a logical screen, ending access to it by the draw
commands if it's the draw screen and restoring the text screen if it's
the view screen. SCREEN CLOSE deallocates any memory reserved for the
screen.
SAMPLE GRAPHIC PROGRAM:
1 TRAP 170 in case of error want text screen
10 GRAPHIC CLR initialize graphics
20 SCREEN DEF 1,0,0,2 define a 320x200x2 graphic screen
30 SCREEN OPEN 1 open it
40 PALETTE 1,0, 0, 0, 0 define screen 1 color 0 = black
50 PALETTE 1,1, 15, 0, 0 define screen 1 color 1 = red
55 PALETTE 1,2, 0, 0,15 define screen 1 color 2 = blue
60 PALETTE 1,3, 0,15, 0 define screen 1 color 3 = green
70 SCREEN SET 1,1 make it the view screen
80 SCNCLR 0 clear screen with palette color 0
90 BORDER 0 set border color to color 0
100 PEN 0,1 make draw pen = color 1 (red)
110 LINE 100,100, 150,150 draw a diagonal red line
120 PEN 0,2 make draw pen = color 2 (blue)
130 BOX 50,50, 50,80, 80,50, 80,80 draw a blue box
140 PEN 0,3 make draw pen = color 3 (green)
150 CHAR 25,50, 1,1,2, "WORDS" draw green text
160 SLEEP 5 pause for 5 seconds
170 SCREEN CLOSE 1 close graphic, get text screen
180 PALETTE RESTORE restore normal system colors
190 BORDER 6 restore normal border color
200 END
SET -- Set various system parameters
The SET command is used to set a system parameter. It always precedes
another command word which identifies the parameter to be changed:
SET DEF - Set default system disk drive
SET DEF device
The BASIC DOS commands default to disk unit 8. Use SET DEF to change
which device these commands default to. This command does not renumber
a disk device, use SET DISK for that. Commands which specify a device
will still access the device they specified. A program can be made
more "user friendly" by either not specifying a drive (thus using the
user's preferred drive) or by specifying device 1. Device number 1
means "use the system default drive, whatever its number is."
10 DIR gets directory of device 8
20 DIR U1 gets directory of device 8
30 DIR U10 gets directory of device 10
40 SET DEF 10 change the default drive to unit 10
50 DIR gets directory of device 10
60 DIR U1 gets directory of device 10
70 DIR U8 gets directory of device 8
SET DISK - Change a disk device number
SET DISK oldnumber TO newnumber
Use this command to renumber (change) a disk drive's unit number. Not
all drives can be renumbered -- refer to your disk drive manual for
details. This command sends to the disk's command channel the
conventional CBM serial disk drive "M-W" command. See also the DISK
command, which lets you send any command to a disk drive.
SET DISK 8 TO 10 Change unit 8's number to 10
Because the built-in C64DX drives always take precedence over serial
bus drives, this is one way to get the built-in drive "out of the way"
so that you can access a serial bus drive #8.
SET DISK # (without [TO #] parameter)
Allows the user to clear DS$ message and specify which drive next DS$
comes from.
SGN -- Get the sign of a number
SGN (expression)
The SiGN function returns the sign of a numeric expression as follows:
If the expression is < 0 (negative) .... returns -1
If the expression is = 0 (zero) ........ returns 0
If the expression is > 0 (positive) .... returns 1
SIN -- Sine function
SIN (expression)
This function returns the sine of X, where X is an angle measured in
radians. The result is in the range -1 to 1.
X = SIN (pi/4) Result is X=0.707106781
To get the sine of an angle measured in degrees, multiply the numeric
expression by pi/180.
SLEEP -- Pause program execution of a specified period of time
SLEEP seconds
Temporarily suspends execution of your program for 1 to 65535 seconds.
SLOW -- Set system speed to 1.02MHz
SLOW is used primarily to directly access "slow mode only" devices
such as the SID sound chips. FAST is the default system speed.
SOUND -- Produce sound effects
SOUND v, f, d [,[dir] [,[m] [,[s] [,[w] [,p] ]]]]
v = voice (1-6)
f = frequency (0-65535)
d = duration (0-32767)
dir = step direction (0(up), 1(down), or 2(oscillate)) default=0
m = min frequency (0-65535) default=0
s = sweep (0-65535) default=0
w = waveform (0=triangle,1=saw,2=square,3=noise) default=2
p = pulse width (0-4095) 50% duty cycle=default=2048
The sound command is a fast and easy way to create sound effects and
musical tones. The first three parameters are required to select the
voice, frequency, and duration of the tone. The duration is specified
in "jiffies" (60 jiffies = 1 second).
Optionally, you can specify a waveform and, for square waves, the
pulse width. The SOUND command can sweep a voice through a series of
equally-spaced frequencies. The direction of the sweep, minimum and
maximum frequencies can be programmed. If time expires before the
sweep is done, the sound stops. If the minimum or maximum frequency is
reached before time expires, the sound repeats.
For programming details, refer to the SID hardware documentation. Use
the VOLume command to change the volume of the sound. Note that the
TEMPO command affects PLAY strings only, not SOUND effects.
FREQout = ( f * 0.0596 ) Hz
PWout = ( p / 40.95 ) %
Each voice can be programmed separately and played simultaneously for
a wide variety of sound effects. Once a sound effect is initiated,
BASIC execution continues with the next statement while the sound
plays out, allowing you to combine and control graphics, animation,
and sound from a BASIC program. The examples below include information
about how to generate precise tones for exact times, but for most
casual users trial and error are perfectly acceptable! (Note that the
values used are for 60Hz (NTSC) systems):
Using voice 1, emit a square-wave, 440Hz tone for 1 second. Note that
440Hz = 7382 * 0.0596 using the above formula.
SOUND 1, 7382, 60
Using voice 2, sweep from 100Hz (m=1638) to 440Hz (f=7382) in
increments of 1Hz (s=17). The time required to do this can be
calculated as t=(f-m)/s, so t=336 jiffies.
SOUND 2, 7382, 336, 0, 1678, 17
Using voice 3, make a neat sound using an oscillating sweep (dir=2)
and a sawtooth waveform (w=1) for 3 seconds (t=180).
SOUND 3, 5000, 180, 2, 3000, 500, 1
SPC -- Space PRINT output
SPC (number)
The SPaCe function is used to format PRINTed data to the screen, a
printer, or a file. It specifies the number of spaces to be skipped,
from 0 to 255. A semicolon (';') is always assumed to follow SPC, even
if it appears at the end of a print line.
The SPC function works a little differently on screen, printer and
disk output. On the screen, SPC skips over characters already on the
screen, which is not the case with printer and disk output. On
printers, if the last character on a line is skipped, the printer
will automatically perform a carriage return and linefeed.
PRINT "123";SPC(3);"456" Displays '123 456'
PRINT "X";SPC(5) :PRINT"X" Displays 'X X'
See also the TAB function. A better way to format PRINT output is with
PRINT USING.
SPRCOLOR -- Set multicolor sprite colors
SPRCOLOR [sprite_mc1] [,sprite_mc2]
Use the SPRITE command to set up a multicolor sprite, and use SPRCOLOR
to set the additional colors. Note that these colors are common to all
multicolor sprites. The color values must be in the range (0-15). Use
the RSPCOL0R function to get the current multicolor sprite colors, and
RSPRITE to get the current sprite foreground color.
SPRDEF -- Define a sprite pattern
[*** NOT EXPECTED TO BE IMPLEMENTED ***]
SPRITE -- Turn a sprite on or off, and set its characteristics
SPRITE number [,[on] [,[color] [,[priority] [,[x_exp] [,[y_exp] [,mode] ]]]]]
The SPRITE command allows you set all of the characteristics of a
sprite. Use the MOVSPR command to position it or set it in motion.
Use the SPRCOLOR to set the multicolor sprite colors, if you are using
multicolor sprites.
All the parameters except the sprite number are optional. If you don't
specify a parameter then it won't be changed.
number = sprite number (0-7)
on = enable (1) or disable(0)
color = sprite foreground color (0-15)
priority= sprite to display data priority:
0 means sprite goes over screen data
1 means sprite goes under screen data
x,y_exp = sprite expansion on (1) or off (0)
mode = sprite mode:
0 high resolution
1 multicolor
The SPRITE command does not define a sprite. The sprite definitions
must be loaded into the sprite area first ($600-$7FF). Use the BLOAD
and BSAVE commands. [*** THIS MAY CHANGE ***] A sprite is 24 pixels
wide and 21 pixels high. Each sprite definition requires 63 ($40 hex)
bytes:
$600 Sprite 0 definition
$640 Sprite 1 definition
$680 Sprite 2 definition
$6C0 Sprite 3 definition
$700 Sprite 4 definition
$740 Sprite 5 definition
$780 Sprite 6 definition
$7C0 Sprite 7 definition
Use the RSPRITE function to read a sprite's characteristics, or the
RSPPOS function to read a sprite's position. The RSPCOLOR function
is used to get the current multicolor sprite colors.
10 BLOAD"sprite 1 data", Load sprite 1's definition
P(DEC("640"))
20 SPRITE 1, 1, 2 Turn it on, make it red
30 MOVSPR 1, 24, 50 Put it at top-leftmost corner
40 SPRSAV 1, 2 Copy sprite 1 definition to 2
50 SPRITE 2, 1, 7 Turn on sprite 2 make it yellow
60 MOVSPR 2, 320, 229 Put it at bottom-rightmost corner
70 BSAVE"sprite 2 data", Save sprite 2
P(DEC("680")) TO P(DEC("6C0"))
80 SPRITE 1, 0 Turn off sprite 1
90 SPRITE 2, 0 Turn off sprite 2
SPRSAV -- Copy a sprite definition
SPRSAV source, destination
Use this command to copy a sprite's data (shape) to another sprite or
into a string variable, or copy a shape from a string variable into a
sprite. You can have many different sprite shapes in memory at one
time, all stored in strings. This makes it possible to animate
sprites from BASIC by quickly "flipping through" shapes, using each
shape like a frame from a movie film.
SPRSAV 0, A$ copy the data (shape) of sprite 0 into A$
SPRSAV A$, 2 copy the data (shape) in A$ into sprite 2
SPRSAV 1, 2 copy the data (shape) in sprite 1 to sprite 2
STASH -- (see the DMA command)
SQR -- Square root function
SQR (number)
This function returns the SQuare Root of the given numeric expression.
The numeric expression must not be negative or an 'ILLEGAL QUANTITY'
error is reported.
A = SQR(10) Result is A = 3.16227766
STEP -- See FOR/NEXT/STEP
STOP -- Halt program execution
When STOP is executed, the computer immediately stops running the
program and reports 'BREAK IN LINE xx'. No variables are cleared and
files are not closed.
This command is usually used while debugging (fixing) a BASIC program,
since it lets you stop at a specific place, examine variables, change
variables, and restart the program where it was halted (see CONTinue
command) or some other line (see GOTO). In many cases, you can even
change the program and use GOTO to resume execution with variables
and open channels intact.
SWAP -- (see the DMA command)
STR$ -- Get the string representation of a number
STR$ (number)
The STRing function returns a string identical to PRINT's output of
the given numeric expression. See PRINT for details regarding the
format of numeric output. STR$ is the opposite of VAL.
A$ = STR$(123) Result is A$ = " 123"
A$ = STR$(-123) Result is A$ = "-123"
A$ = STR$(.009) Result is A$ = " 9E-03"
SYS -- Call a ROM routine or user machine language routine
SYS address [,[a] [,[x] [,[y] [,[z] [,s] ]]]]
This statement performs a call to a machine language routine at the
specified address (range 0-65535, $3000-$FFFF) in a memory bank set
up previously by the BANK command.
The microprocessor's registers are loaded with the values specified in
the parameters following the address (if given) and a JSR (Jump
SubRoutine) instruction is performed. When the called routine ends
with an RTS (ReTurn from Subroutine), the microprocessor's registers
are saved and control is returned to the BASIC program. The
microprocessor's registers can be examined with the RREG command.
Because this command instructs the computer's microprocessor (CPU) to
perform something, extreme care should be taken in its use. It can
easily crash the computer if you do something wrong (press the reset
button to reboot). Also see the BOOT SYS command.
BANK 128: SYS DEC("FF5C") Call the Kernel's PHOENIX routine.
BANK 128: SYS DEC("FF81") Reset the Screen Editor
10 BANK 128
20 BLOAD"user routine",P(DEC("1800")) Load a user routine
30 SYS DEC("1800"), areg, xreg Call it with args in A and X
40 RREG areg, xreg, , , sreg Get args back in A, X, and S
50 carry = (sreg AND 1) Get carry flag from S
60 PRINT "ACCUMULATOR = ";HEX$(areg) Display registers
70 PRINT "X REGISTER = ";HEX$(xreg)
80 PRINT "CARRY FLAG = ";carry
See the USR function for another way to call machine language
routines.
TAB -- Space PRINT output
TAB (number)
The TAB function is used to format PRINTed data to the screen, a
printer, or a file. It's primarily for screen text output, moving
the cursor to the specified column (plus one) as long as the current
print position is not already beyond that point (for example, if the
current print position is the first column, TAB(1) would print
subsequent text beginning in column 2). If the current print position
is already beyond the column specified by the TAB function, nothing is
done. For disk and printer output, TAB works exactly like the SPC
function (see SPC).
A semicolon (';') is always assumed to follow TAB, even if it appears
at the end of a print line.
PRINT "TEXT";TAB(10);"HERE" Result is 'TEXT HERE'
PRINT "TEXT";SPC(10);"HERE" Result is 'TEXT HERE'
The above examples illustrate the difference between TAB and SPC. See
also the SPC function. A better way to format PRINT output is with
PRIUT USING. Don't confuse the TAB function with the TAB character,
CHR$(9), which is used to format data using the programmable TAB
stops.
TAN -- Tangent function
TAN (expression)
This function returns the tangent of the numeric expression, measured
in radians. If the result overflows, TAN(pi/2) for example, an
'OVERFLOW' error is reported.
X = TAN(1) Result is X=1.55740772
To get the tangent of an angle measured in degrees, multiply the
numeric expression by pi/180.
TEMPO -- Set the tempo (speed) of a PLAY string
TEMPO rate
Use this command to adjust the tempo (speed) of music playback by the
PLAY command. The rate determines the duration of a whole note. The
default is 12, making a whole in 4/4 time last 2 seconds. The formula
is:
duration = 24/rate
The higher the rate, the faster the note. The range is (1-255).
THEN -- See IF/THEN/ELSE
TO -- See FOR/NEXT/STEP. Also used as a subcommand.
TRAP -- Define an BASIC error handler
TRAP [line_number]
When turned on, TRAP intercepts all BASIC execution error conditions
except 'UNDEF'D STATEMENT ERROR'. Even the STOP key can be TRAPped.
When an error occurs, BASIC saves the error's location, line number,
and error number. If TRAP is not set, BASIC returns to direct mode
and displays the error message and line number. If TRAP is set, BASIC
performs a GOTO to the line number specified in the TRAP statement and
continues executing.
Your BASIC error handling routine can examine the error number,
message, and the line number where the error occurred and determine
the proper course of action. The system error words are:
ER Error Number
EL Error Line (line where the error occurred)
ERR$() Error Message
If ER is -1, then a BASIC error did not occur. The error routine
should check the disk status words, in case they were the cause of
the error:
DS Disk Error Number
DS$ Disk Error Message
Refer to the list of BASIC and Disk error messages in the appendix.
Note that an error in your TRAP routine cannot be trapped. The RESUME
statement can be used to resume execution -- see RESUME.
TRAP with no line number specified turns off error TRAPping.
10 TRAP 90 enable trapping
20 FOR I=-5 TO 5
30 PRINT 5/I error when I=0
40 NEXT
50 TRAP turn trapping off
60 END
70 :
90 PRINT ERR$(ER): RESUME NEXT error routine
TROFF -- Turn off trace mode
TRON -- Turn on trace mode
TROFF
TRON
Trace mode is used while debugging (fixing) a BASIC program. TRON
enables tracing, and TROFF disables tracing. When the program is run
and trace mode is on, the line number of the command that is being
executed is displayed on the screen. If there are three commands on
the line, the line number will be displayed three times, once each
time one of the commands is executed. Trace mode lets you know what
the computer is doing.
Trace mode works even when a graphic screen is being displayed, but
the line number is still displayed on the text screen so you won't be
able to see it until the graphic screen is turned off. If your program
is doing alot of PRINT statements, the display can seen a little
confusing.
Trace mode can be set in direct mode to trace the entire program, or
it can be turned on and off from within your program to let you trace
only selected portions of the program.
Trace mode has no effect on commands entered in direct (edit) mode.
The NEW command disables trace mode, but RUN and CLR do not.
10 FOR I=-5 TO 5
15 TRON
20 PRINT 5/I
25 TROFF
30 NEXT
TYPE -- Display the contents of a sequential disk file
TYPE "filename" [,Ddrive] [<,|ON>Udevice]
Use this command to print the contents of a PETSCII data file on the
screen. The file must contain lines no longer than 255 characters long
and terminated by a return character (CHR$(13)). Lines too long result
in a 'STRING TOO LONG' error.
TYPE "readme" display the contents of the README file on the screen
The command sequence below will print the contents of the README file
on a CBM serial bus printer in upper/lower case mode.
OPEN 4,4,7: CMD4: TYPE"readme": CLOSE4
UNTIL -- See DO/LOOP/WHILE/UNTIL/EXIT
USR - Call a user defined machine language function
USR (expression)
When this function is used, the program jumps to a machine language
subroutine whose starting address must be POKEd into system memory
(BANK 128) at address 760 (low byte) and 761 (high byte), or $2F8 hex.
The floating point value of the numeric expression is passed to the
routine in the Floating point ACCumulator (FACC), and the value to
be returned is taken from the FACC when the routine ends.
If the USR vector is not set up prior to making the USR call, an
'UNDEF'D FUNCTION' error is reported. The routine must be located in
the system bank. The BANK command does not affect USR.
Using this method of calling a machine language routine requires a
fair amount of set up and a good knowledge of the lower level math
routines built into BASIC. See the SYS command, which is more commonly
used to call a machine language routine.
The following program illustrates the basic steps required for
installing a USR routine and calling it:
10 BANK 128 System bank for poke & load
20 UV = DEC("1800") Where my routine is
30 BLOAD "my user routines",P(UV) Load my routine
40 POKE DEC("2F8"), UV AND 255, UV / 256 Set up USR address
50 x = USR(123): PRINT X Call my routine with the
the value 123, get back and
print whatever my routine
leaves in FACC
The following program actually works. It points the USR vector to the
BASIC math jump table entry for the routine which inverts the sign
of the number in the FACC. Type in positive & negative numbers:
10 BANK 128 System bank for poke
20 POKE DEC("2F8"), DEC("33"), DEC("7F") Set up USR address
30 DO: INPUT"SIGNED NUMBER"; N Get number input
40 : PRINT USR(N) Display USR output
50 : LOOP UNTIL N=0 End if user types zero
USING -- See PRINT USING
VAL -- Get the numerical value of a string
VAL (string)
The VALue function converts a string into a number. The conversion
starts with the first character and ends at the end of the string or
the first character that is not allowed in normal number input. Spaces
are ignored. If the first character of the string is not a legal
character, a zero is returned.
The VAL function works the same way the INPUT and READ commands do.
VAL is the opposite of STR$.
X = VAL(" 123") Result is X = 123
X = VAL("-123") Result is X = -123
X = VAL(" 9E-02") Result is X = .09
VERIFY -- Compare a program or data in memory with a disk file
VERIFY "filename" [,device_number [,relocate_flag]]
This command is just like a LOAD command, except instead of putting
the data read from a file into memory, the computer compares it to
what is already in memory. If there's any difference at all a 'VERIFY
ERROR' is reported.
The filename must be given, and pattern matching may be used. In the
case of dual drive systems, the drive number must be part of the
filename. If a device number is given, the file is sought on that
unit, which must be a disk drive. If a device number is not given,
the default system drive is used. See also DVERIFY.
Note: If the BASIC program in memory is not located at the same
address as the version on disk was SAVEd from, the files will not
match even if the program is otherwise identical.
The relocate_flag is used to VERIFY binary files. If the relocate_flag
is present and non-zero, the file will be compared to memory starting
at the address stored on disk when the file was SAVEd. The memory bank
used is the bank given in the last BANK statement. The ending address
is determined by the length of the disk file. The comparison halts
on the first mismatch or at the end of the file. The area to be
compared must be confined to the indicated memory bank. Do not use
the relocate_flag to verify BASIC programs. See also BVERIFY.
VERIFY "myprogram"
Good: SEARCHING FOR 0:myprogram Bad: SEARCHING FOR 0:myprogram
VERIFYING VERIFYING
OK ?VERIFY ERROR
VERIFY "PROG" Compares BASIC program in memory to file PROG
on the default system disk.
VERIFY FILE$,DRV Compares program in memory to a program whose
name is in the variable FILE$ on the unit
whose number is in DRV.
VERIFY "0:PROG",8 Compares memory to BASIC program PROG on unit
8, drive 0.
BANK 128 Compares a binary file into memory. The
VERIFY "BIN",8,1 address used comes from the disk file, but
you must specify the memory bank.
VIEWPORT -- [*** CURRENTLY UNIMPLEMENTED ***]
VOL -- Set audio volume level
VOL volume
[*** THIS COMMAND WILL CHANGE ***]
This statement sets the volume level for SOUND and PLAY statements.
VOLUME can be set from 0 to 15, where 15 is the maximum volume. A
volume of 0 turns sound output off. VOLume affects all 3 voices.
Note that PLAY strings can change the volume, too.
WAIT -- Pause BASIC program until a memory state satisfied
WAIT address, and_mask [,xor_mask]
The WAIT statement causes program execution to be suspended until data
at a specified memory location matches a given bit pattern. It's used
to pause your program until an event occurs.
The event could be an I/O state (such as a fire button or peripheral
port change), a hardware state (such as the raster position or RS232
status), or memory change caused by an interrupt event (such as a
keyboard scan).
The WAIT statement tells the computer to read (PEEK) a memory location
(0-65535) and AND the value it got with the number in and_mask
(0-255). If the result is zero, repeat the operation until the result
is not zero. This is like the following BASIC instructions, but much
faster:
DO: result = PEEK(address): LOOP UNTIL (result AND and_mask) <> 0
This works if the state you are WAITing for is non-zero (a one or
"high" state). If you want to wait for a zero state (a "low" state),
you need to use the xor_mask option to "flip" the bits of the result.
Note that it's possible to "hang" your program indefinitely if the
state you are waiting for never happens or you specify the wrong data.
Press the STOP and RESTORE keys at the same time to get control back.
Be sure to use the BANK command before you tell the computer to WAIT
to specify which 64K memory bank the address is in. Note that a BANK
number greater than 127 (i.e., a bank number with the most significant
bit set) must be used to address an I/O location, such as the VIC
chip. Refer to the system memory map for details.
10 BANK 128 Wait for the VIC raster to be
20 WAIT DEC("D011"), 128 offscreen (want RC8 = 1)
10 BANK 128 Wait for the VIC raster to be
20 WAIT DEC("D011"), 128, 128 onscreen (want RC8 = 0)
10 BANK 128
20 WAIT DEC("D3"), 1 Wait for user to press <SHIFT> key
30 WAIT DEC("D3"), 2 Wait for user to press <C=> key
40 WAIT DEC("D3"), 4 Wait for user to press <CTRL> key
50 WAIT DEC("D3"), 8 Wait for user to press <ALT> key
WHILE -- See DO/LOOP/WHILE/UNTIL/EXIT
WIDTH -- [*** CURRENTLY UNIMPLEMENTED ***]
WINDOW -- Set a text window
WINDOW left_column, top_row, right_column, bottom_row [,clear]
This command defines a logical text screen window. All text I/O will
be confined to this window. The row parameters must be in the range
(0-24), and the column parameters must be in the range (0-79) for
80-column screens or (0-39) for 40-column screens. The parameters are
always referenced to the physical screen (i.e., you cannot define a
window within a window). If the clear flag is given, the new window
area will be cleared after it's set up.
Use the RWINDOW function to get the current window size.
You are responsible for saving and restoring screen data in all
windows because the WINDOW command simply sets the window margins. The
WINDOW command does not draw a border around a window. All color
commands and screen modes (such as scroll disable, TAB stops, etc.)
are global.
Two consecutive "home" characters will reset the window definition
back to the physical screen.
WINDOW 0,0,39,24 Define a window in 80-column mode
that is the left half of the screen.
WINDOW 40,0,79,24 Define a window in 80-column mode
that is the right half of the screen.
WINDOW 0,0,79,12 Define a window in 80-column mode
that is the top half of the screen.
WINDOW 0,13,79,24 Define a window in 80-column mode
that is the bottom half of the screen.
WINDOW 20,6,59,12,1 Define a window in 80-column mode in
the center of the screen and clear it.
The window is 12 characters high and
40 characters wide.
PRINT CHR$(19)CHR$(19); Reset the window back to full screen
in either 40 or 80-column mode and put
the cursor in top left corner.
XOR -- Exclusive-Or function
XOR (number,number)
The XOR function returns a numeric value equal to the logical XOR of
two numeric expressions, operating on the binary value of the unsigned
16-bit integers in the range (0 to 65535). Numbers outside this range
result in an 'ILLEGAL QUANTITY' error.
X = XOR(4,12) Result is X= 8
X = XOR(2,12) Result is X=14
3.1.4. VARIABLES
The C64DX uses three types of variables in BASIC:
floating point X
integer X%
string X$
Normal NUMERIC VARIABLES, also called floating point variables,
can have any from up to nine digits of accuracy. When a number becomes
larger than nine digits can show, as in +10 or -10, the computer
displays it in scientific notation form, with the number normalized to
1 digit and eight decimal places, followed by the letter E and the
power of ten by which the number is multiplied. For example, the
number 12345678901 is displayed as 1.23456789E+10.
INTEGER VARIABLES can be used when the number is a signed whole
number from +32767 to -32768. Integer data is a number like 5, 10, or
-100. Integers take up less space than floating point variables,
particularly when used in an array.
STRING VARIABLES are those used for character data, which may
contain numbers, letters, and any other character that the computer
can make. An example of string data is "Commodore C64DX".
VARIABLE NAMES may consist of a single letter, a letter followed
by a number, or two letters. Variable names may be longer than 2
characters, but only the first two are significant. An integer is
specified by using the percent (%) sign after the variable name.
String variables have a dollar sign ($) after their names.
EXAMPLES:
Numeric Variable Names: A, A5 , BZ
Integer Variable Names: A%, A5%, BZ%
String Variable Names : A$, A5$, BZ$
ARRAYS are lists of variables with the same name, using an extra
number (or numbers) to specify an element of the array. Arrays are
defined using the DIM statement, and may be floating point, integer,
or string variable arrays. The array variable name is followed by a
set of parentheses () enclosing the number of the variable in the
list.
EXAMPLE:
A(7), BZ%(11), A$(87)
Arrays can have more than one dimension. A two dimensional array
may be viewed as having rows and columns, with the first number
identifying the row and the second number identifying the column (as
if specifying a certain grid on the map).
EXAMPLE:
A(7,2), BZ%(2,3,4), Z$(3,2)
RESERVED VARIABLE NAMES are names that are reserved for use by
the computer, and may not be used for another purpose. These are the
variables DS, DS$, ER, ERR$, EL, ST, TI, and TI$. KEYWORDS such as TO
and IF or any other names that contain KEYWORDS, such as RUN, NEW, or
LOAD cannot be used.
ST is a status variable for input and output (except normal
screen/keyboard operations). The value of ST depends on the results of
the last I/O operation. In general, if the value of ST is 0 then the
operation was successful.
TI and TI$ are variables that relate to the real-time clock built
into the C64DX. The system clock is reset to zero when the system is
powered up or reset, and can be changed by the user or a program.
TI$="hh:mm:ss.t" Allows optional colons to delimit parameters and
allows input to be abbrieviated (eg., TI$="h:mm"
or even TI$=""), defaulting to "00" for
unspecified parameters. 24-hour clock (00:00:00.0
to 23:59:59.9).
TI 24-hour TOD converted into tenths of seconds.
The value of the clock is lost when the computer is turned off.
It starts at zero when the computer is turned on, and is reset to zero
when the value of the clock exceeds 23:59:59.9.
The variable DS reads the disk drive command channel, and returns
the current status of the drive. To get this information in words,
PRINT DS$. These status variables are used after a disk operation,
like DLOAD or DSAVE, to find out why the error light on the disk drive
is blinking.
ER, EL, and ERR$ are variables used in error trapping routines.
They are usually only useful within a program. ER returns the last
error encountered since the program was RUN. EL is the line where the
error occurred. ERR$ is a function that allows the program to print
one of the BASIC error messages. PRINT ERR$(ER) prints out the proper
error message.
3.1.5. OPERATORS
The BASIC OPERATORS include ARITHMETIC, RELATIONAL, and LOGICAL
OPERATORS. The ARITHMETIC operators include the following signs:
+ addition
- subtraction
* multiplication
/ division
^ raising to a power (exponentiation)
On a line containing more than one operator, there is a set order
in which operations always occur. If several operators are used
together, the computer assigns priorities as follows. First
exponentiation, then multiplication and division, and last, addition
and subtraction. If two operators have the same priority, then
calculations are performed in order from left to right. If these
operations are to occur in a different order, BASIC 10.0 allows giving
a calculation a higher priority by placing parentheses around it.
Operations enclosed in parentheses will be calculated before any other
operation. Make sure that the equations have the same number of left
and right parentheses, or a SYNTAX ERROR message is posted when the
program is run.
There are also operators for equalities and inequalities, called
RELATIONAL operators. Arithmetic operators always take priority over
relational operators.
= is equal to
< is less than
> is greater than
<= or =< is less than or equal to
>= or => is greater than or equal to
<> or >< is not equal to
Finally, there are three LOGICAL operators, with lower priority
than both arithmetic and relational operators:
AND
OR
NOT
These are most often used to join multiple formulas in IF...THEN
statements. When they are used with arithmetic operators, they are
evaluated last (i.e., after + and -). If the relationship stated in
the expression is the true the result is assigned an integer of -1 and
if false an integer of 0 is assigned. There is also an XOR function.
EXAMPLES:
IF A=B AND C=D THEN 100 requires both A=B & C=D to be true
IF A=B OR C=D THEN 100 allows either A=B or C=D to be true
A=5:B=4:PRINT A=B displays 0
A=5:B=4:PRINT A>3 displays -1
PRINT 123 AND 15:PRINT 5 OR 7 displays 11 and 7
3.1.6. ERROR MESSAGES
3.1.6.1. BASIC ERROR MESSAGES
The following error messages are displayed by BASIC. Error
messages can also be displayed with the use of the ERR$() function.
The error number refers only to the number assigned to the error for
use with this function. In direct mode, DOS error messages (DS$) are
automatically displayed. They are described in the section after this
one.
ERROR# ERROR NAME DESCRIPTION
----------------------------------------------------------------------
1 TOO MANY FILES There is a limit of 10 files OPEN at one
time.
2 FILE OPEN An attempt was made to open a file using
the number of an already open file.
3 FILE NOT OPEN The file number specified in an I/O
statement must be opened before use.
4 FILE NOT FOUND No file with that name exists on the
specified drive.
5 DEVICE NOT PRESENT The required I/O device not available.
6 NOT INPUT FILE An attempt made to read data from a file
that was opened for writing.
7 NOT OUTPUT FILE An attempt was made to write data to a
file that was opened for reading.
8 MISSING FILE NAME Filename was missing in command.
9 ILLEGAL DEVICE NUMBER An attempt was made to use a device
improperly (SAVE to the screen, etc) or
an illegal device number was specified.
10 NEXT WITHOUT FOR Either loops are nested incorrectly, or
there is a variable name in a NEXT
statement that doesn't correspond with
one in FOR.
11 SYNTAX ERROR A statement is unrecognizable by BASIC.
This could be because of missing or
extra parenthesis, parameters, delimiters,
or a misspelled keyword.
12 RETURN WITHOUT GOSUB A RETURN statement was encountered when no
GOSUB statement was active.
13 OUT OF DATA A READ statement was encountered with no
DATA left unREAD.
14 ILLEGAL QUANTITY A number used as an argument is outside
the allowable range (too big or too small)
15 OVERFLOW The result of a computation is larger than
the largest number allowed (1.701411834E+38)
16 OUT OF MEMORY There is not enough memory for the program,
or variables, or there are too many DO, FOR
or GOSUB statements in effect.
17 UNDEF'D STATEMENT A line number referenced doesn't exist.
18 BAD SUBSCRIPT The program tried to reference an element
of an array out of the range specified by
a DIM statement, a missing DIM statement
or a mistyped function name.
19 REDIM'D ARRAY An array can only be DIMensioned once.
20 DIVISION BY ZERO Division by zero is illegal.
21 ILLEGAL DIRECT Command is only allowed to be used in a
program.
22 TYPE MISMATCH A numeric variable was used in place of
a string variable or vice versa.
23 STRING TOO LONG An attempt was made to assign more than
255 characters to a string, or enter more
than 160 characters from the keyboard, or
to input more than 255 characters from a
file.
24 FILE DATA The wrong type of data was read from a
file.
25 FORMULA TOO COMPLEX An expression is too complicated for BASIC
to process all at one time. Break it into
smaller pieces or use fewer parentheses.
26 CAN'T CONTINUE The CONT command does not work if the
program was not RUN, there was an error
or a line has been edited.
27 UNDEFINED FUNCTION An attempt was made to use a user defined
function that was never defined.
28 VERIFY The program on disk does not match the
program in memory.
29 LOAD There was a problem loading.
30 BREAK The program was halted by the STOP key or
a STOP statement.
31 CAN'T RESUME A RESUME statement was encountered without
a TRAP in effect, or an error occurred in
the trap handler itself.
32 LOOP NOT FOUND The program encountered a DO statement and
cannot find the corresponding LOOP.
33 LOOP WITHOUT DO A LOOP was encountered without a DO
statement active.
34 DIRECT MODE ONLY A command was used in a program that can
only be used in direct mode.
35 NO GRAPHICS AREA A graphics command was used before a
graphics screen was defined and opened.
36 BAD DISK A BOOT SYS command failed because the disk
could not be read.
37 BEND NOT FOUND A BEND statement not found for BEGIN.
38 LINE NUMBER TOO LARGE A line number cannot exceed 64000.
39 UNRESOLVED REFERENCE Renumber failed because a referenced line
number does not exist.
40 UNIMPLEMENTED COMMAND The given command is not currently
implemented in this computer.
41 FILE READ There was a problem reading data from a
disk file. Similar to LOAD ERROR.
3.1.6.2. DOS ERROR MESSAGES
The following error messages are returned through the DS and DS$
variables. If a disk command is type in direct mode, these messages
will be displayed automatically. NOTE: DOS message numbers less than
20 are advisory and are not necessarily errors. DOS messages may vary
slightly depending upon the drive model. Refer to your DOS manual for
details.
ERROR # DESCRIPTION
------- --------------------------------------------------------------
00: OK (no error)
01: FILES SCRATCHED (not an error)
The following number (track) tells how many files were deleted
by the scratch command.
02: PARTITION SELECTED (not an error)
The requested disk partition (subdirectory) has been selected.
03: FILES LOCKED
The requested file(s) have been locked.
04: FILES UNLOCKED
The requested file(s) have been unlocked.
05: FILES RESTORED
The requested file(s) have been recovered (undeleted).
20: READ ERROR (block header not found)
The disk controller is unable to locate the header of the
requested data block. Caused by an illegal sector number, or
the header has been destroyed.
21: READ ERROR (no sync character)
The disk controller is unable to detect a sync mark on the
desired track. Caused by misalignment of the read/write head,
no diskette is present, or unformatted or improperly seated
diskette. Can also indicate a hardware failure.
22: READ ERROR (data block not present)
The disk controller has been requested to read or verify a
data block that was not properly written. This error occurs in
conjunction with the BLOCK commands and indicates an illegal
track and/or sector request.
23: READ ERROR (checksum error in data block)
This error message indicates that there is an error in one or
more of the data bytes. The data has been read into the DOS
memory, but the checksum over the data is in error. This
message may also indicate grounding problems.
24: READ ERROR (byte decoding error)
The data or header has been read into the DOS memory, but a
hardware error has been created due to an invalid bit pattern
in the data byte. This message may also indicate grounding
problems.
25: WRITE ERROR (write-verify error)
This message is generated if the controller detects a mismatch
between the written data and the data in the DOS memory.
26: WRITE PROTECT ON
This message is generated when the controller has been
requested to write a data block while the write protect switch
is depressed.
27: READ ERROR
This message is generated when a checksum error is in the
header.
28: WRITE ERROR
This error message is generated when a data block is too long.
29: DISK ID MISMATCH
This message is generated when the controller has been
requested to access a diskette which has not been initialized.
The message can also occur if a diskette has a bad header.
30: SYNTAX ERROR (general syntax)
The DOS cannot interpret the command sent to the command
channel. Typically, this is caused by an illegal number of
file names, or patterns are illegally used. For example, two
file names appear on the left side of the COPY command.
31: SYNTAX ERROR (invalid command)
The DOS does not recognize the command. The command must start
in the first position.
32: SYNTAX ERROR (invalid command)
The command sent is longer than 58 characters.
33: SYNTAX ERRROR (invalid file name)
Pattern matching is invalidly used in the OPEN or SAVE
command.
34: SYNTAX ERROR (no file given)
The file name was left out of the command or the DOS does not
recognize it as such.
39: SYNTAX ERROR (invalid command)
This error may result if the command sent to the command
channel (secondary address 15) is unrecognized by the DOS.
40: UNIMPLEMENTED COMMAND
Command is not implemented at this time.
41: FILE READ
The file cannot be read.
50: RECORD NOT PRESENT
Result of disk reading past the last record through INPUT# or
GET# commands. This message will also occur after positioning
to a record beyond end_of_file in a relative file. If the
intent is to expand the file by adding the new record (with a
PRINT# command), the error message may be ignored. INPUT and
GET should not be attempted after this error is detected
without first repositioning.
51: OVERFLOW IN RECORD
PRINT# statement exceeds record boundary. Information is
truncated. Since the carriage return which is sent as a record
terminator is counted in the record size, this message will
occur if the total characters in the record (including the
final carriage return) exceeds the defined size.
52: FILE TOO LARGE
Record position within a relative file indicates that disk
overflow will result.
53: BIG RELATIVE FILES DISABLED
60: WRITE FILE OPEN
This message is generated when a write file that has not been
closed is being opened for reading.
61: FILE NOT OPEN
This message is generated when a file is being accessed that
has not been opened in the DOS. Sometimes, in this case, a
message is not generated: the request is simply ignored.
62: FILE NOT FOUND
The requested file does not exist on the indicated drive.
63: FILE EXISTS
The file name of the file being created already exists on the
diskette.
64: FILE TYPE MISMATCH
The requested access mode is not possible using the filetype
given.
65: NO BLOCK
The sector you tried to allocate with the B-A command was
already allocated. The track and sector numbers hold the next
higher, available track and sector. If the track number is
zero, no higher sectors are free (try a lower track & sector).
66: ILLEGAL TRACK AND SECTOR
The DOS has attempted to access a track or block which does
not exist in the format being used. This may indicate a
problem reading the pointer of the next block.
67: ILLEGAL SYSTEM T OR S
This special error message indicates an illegal system track
or sector.
70: NO CHANNEL
The requested channel is not available, or all channels are in
use. A maximum of five sequential files may be opened at one
time to the DOS. Direct access channels may have six opened
files.
71: DIRECTORY ERROR
The BAM is corrupted. Try initializing the disk.
72: DISK FULL
Either the blocks on the diskette are used or the directory is
at its entry limit. DISK FULL is sent when two blocks are
available to allow the current file to be closed before its
data is lost.
73: DOS MISMATCH (also the powerup message)
Initially given at powerup to identify the drive. On some
drives this message is given as an error to indicate the
media was formatted by an incompatible DOS.
74: DRIVE NOT READY
An attempt has been made to access the Floppy Disk Drive
without any diskette present.
75: FORMAT ERROR
76: CONTROLLER ERROR
The DOS has determined that the hardware is malfunctioning.
77: SELECTED PARTITION ILLEGAL
An attempt was made to access a partition as a subdirectory,
but it has no directory track or does not meet the criteria
of a directory partition.
78: DIRECTORY FULL
There is no more room in the directory sector for another file
entry. Delete a file to make room, or change disks.
79: FILE CORRUPTED
The DOS has determined that a file is bad, probably having bad
links. Prepare a new disk and copy the good files to it.
Could be the result of an unsuccessful file recovery.
3.2. MACHINE LANGUAGE MONITOR
3.2.1. INTRODUCTION
The MONITOR is a built in machine language program that lets the
user easily write machine language programs. The C64DX MONITOR
includes a machine language monitor, an assembler, and a disassembler.
Machine language programs written using the MONITOR can run by
themselves, or be used as very fast 'subroutines' for BASIC programs.
Care must be taken to position the assembly language programs in
memory so that the BASIC program does not overwrite them and the
proper memory is in context at all times (including during
interrupts).
3.2.2. MONITOR COMMANDS
A ASSEMBLE - Assemble a line of 4502 code
C COMPARE - Compare two sections of memory
D DISASSEMBLE - Disassemble a line of 4502 code
F FILL - Fill a section of memory with a value
G GO - Start execution at specified address
H HUNT - Find specified data in a section of memory
L LOAD - Load a file from disk
M MEMORY - Dump a section of memory
R REGISTERS - Display the contents of the 4502 registers
S SAVE - Save a section of memory to a disk file
T TRANSFER - Transfer memory to another location
V VERIFY - Compare a section of memory with a disk file
E EXIT - Exit Monitor mode
. <period> - Assembles a line of 4502 code
> <greater-than> - Modifies memory
; <semicolon> - Modifies register contents
@ <at sign> - Display disk status
$ <hex> - Display hex, decimal, octal, and binary value
+ <decimal>
& <octal>
% <binary>
The MONITOR accepts binary, octal, decimal and hexadecimal values for
any numeric field. Numbers prefixed by one of the characters $ + & %
are interpreted as base 16, 10, 8, or 2 values respectively. In the
absence of a prefix, the base defaults to hexadecimal always.
The assembler will use the base page form of an instruction wherever
possible unless the address field is preceded by extra zeros to force
the absolute form (except binary notation).
The most significant byte of a 24-bit (3-byte) address field specifies
the memory BANK to implement at the time the given command is
executed. BANK bytes with the MSB set (i.e., banks greater than $7F)
mean "use the current system configuration", which always includes the
I/O area. If a BANK is not specified, BANK 0 is assumed.
BANK 00 internal RAM bank 0 (System, BASIC program)
BANK 01 internal RAM hank 1 (DOS, BASIC vars, color bytes)
BANK 02 internal ROM bank 0 (DOS, C64 mode, CHRSETS)
BANK 03 internal ROM bank 1 (Monitor, C65 mode)
BANK 04-07 reserved for future expansion
BANK 08-7F expansion RAM (graphic screens, RAM disk, etc.)
BANK 80-FF MSB set means current config & I/O
The monitor supports the editor autoscroll feature for memory dumps
(forwards and backwards) and disassemblies (forward disassembly only).
To send dump output to a printer, from BASIC open a CMD channel to the
printer and enter the monitor (OPEN 4,4: CMD4: MONITOR). Give the dump
command desired; output will be to the printer.
3.2.3. MONITOR COMMAND DESCRIPTIONS
COMMAND: A
PURPOSE: Enter a line of assembly code.
SYNTAX: A <address> <mnemonic> <operand>
<address> A number indicating the location in memory to place the
assembled binary code.
<mnemonic> A 4502 assembly language mnemonic, eg., LDA
<operand> The operand, when required, can be of any of the legal
addressing modes.
A <RETURN> is used to indicate the end of the assembly line. If are
any errors on the line, a question mark is displayed to an error, and
the cursor moves to the next line. The screen can be used to correct
the error(s) on that line.
As each line is entered, the machine code is written to the specified
address and the line is automatically disassembled.
Base page and relative addresses are calculated for you, and the
appropriate word or byte relative mode selected automatically. To
force an absolute addressing mode, supply leading zeros if necessary.
.A 1800 LDX #$00
.A 1802
NOTE: A period (.) is equal to the ASSEMBLE command.
. 1900 LDA #$23
COMMAND: C
PURPOSE: Compare two areas of memory
SYNTAX: C <address_1> <address_2> <address_3>
<address_1> A number indicating the start of the area of memory to
compare against.
<address_2> A number indicating the end of the area of memory to
compare against.
<address_3> A number indicating the start of the other area of
memory to compare with.
The following example compares $8000-$9FFF in bank 0 with $8000-$9FFF
in bank 1. Addresses of data that does not match are printed on the
screen.
C 8000 9FFF 18000
COMMAND: D
PURPOSE: Disassemble machine code
SYNTAX: D [address_1 [address_2] ]
<address_1> A number setting the address to start the disassembly.
<address_2> An optional ending address of code to be disassembled.
The output of the disassembly is the same as that of an assembly, only
preceded by a comma instead of an A or period. The object code is also
displayed. Relative addresses in the disassembly are displayed as the
16-bit destination.
A disassembly listing can be modified using the screen editor. Any
changes to the mnemonic or operand on the screen, then hit the
<RETURN>. This enters the line and calls the assembler for
instructions. The object code cannot be modified this way.
A disassembly can be paged. Typing a D<RETURN> causes the next of
disassembly to be displayed. The autoscroll feature works in forward
mode only, because backwards disassembly is not possible because all
256 opcodes are defined in the 4502 processor.
The following example disassembles from ROM bank 3:
D 3F000 3F005
. 03F000 A9 09 LDA #$09
. 03F002 A0 FF LDY #$FF
. 03F004 18 CLC
. 03F005 86 C2 STX $C2
Note that banks wrap to the next higher bank number.
COMMAND: F
PURPOSE: Fill a range of locations with a specified byte.
SYNTAX: F <address_1> <address_2> <byte>
<address_1> The first location to fill with the <byte>.
<address_2> The last location to fill with the <byte>.
<byte> The byte to fill with
This command is useful for initializing data structures or any other
RAM area.
F 00600 007FF 00
Fills memory locations from $0600 to $07FF (RAM-0) with $00. Note that
banks wrap to the next higher bank number. The maximum area that can
be filled at one time is 64K, limited by the DMA device.
COMMAND: G
PURPOSE: Perform a JMP to a specified address
SYNTAX: G <address>
<address> The address where execution is to start. When the
address is not specified, execution begins at the
current PC. (The current PC can be viewed or changed
with the R command.)
The GO command loads the processor's registers (displayable by the R
command) and performs a JMP to the specified starting address.
Caution is recommended in using the GO command. To return to MONITOR
mode after performing a GO command, a BRK instruction must end the
called routine. Also, the BANK specified must be able to handle
interrupts (note that BANK bytes less than $80 do NOT include the
operating system or I/O space).
G FFC800
JuMPs to address $C800 in bank $FF (system configuration).
COMMAND: H
PURPOSE: Hunt through memory within a specified range for all
occurences of a set of bytes.
SYNTAX: H <address_1> <address_2> <data>
<address_1> Address to start at
<address_2> Last address
<data> Data to search for. May be a number, sequence of
numbers, or a PETSCII string.
H 02000 0FFFF 46 52 45 44
Hunts for the series of bytes $46, $52, $45, $44 in memory bank 0
beginning at address $2000 and ending at $FFFF. The addresses of
matches is displayed.
H 0200 0FFFF 'FRED
Hunts for the PETSCII string following an apostrophe. Note that banks
wrap to the next higher bank number.
COMMAND: L
PURPOSE: Load a file from disk.
SYNTAX: L <"filename"> [,device [,load_address] ]
<"filename"> Is a filename in quotes.
[device] Is a number indicating the device to load from.
[load_address] Optional load address. If not given, the file is
loaded into memory at the 16-bit address stored on
disk (always RAM bank 0).
The LOAD command causes a file to be loaded into memory. If the load
address (including BANK) is given, the data is placed there. Otherwise
the file is loaded into RAM bank 0 at the 16-bit load address
specified by the first two bytes read from the PRG (program) type
file. An error occurs if a load overflow the specified bank.
L "filename"
Loads "filename" from default system drive into RAM bank 0 at the
address read from the file.
L "filename",+10,80000
Loads "filename" from drive 10 (notice you must specify decimal for
the drive number, or use hex equivalent) into expansion memory bank
8 at address $0000. Note that spaces between parameters after the
filename are not permitted.
COMMAND: M
PURPOSE: Dump a section of memory in hex and PETSCII.
SYNTAX: M [address_1 [address_2] ]
[address_1] Starting address of memory dump. If omitted, one page
is displayed starting from the last address used.
[address_2] Ending address of memory dump. If omitted, one page
is displayed starting at address_1.
Memory dump width is sized to 40 or 80 columns, depending upon the
text screen width. All data is displayed in hexadecimal and followed
by a PETSCII interpretation of the data in reverse field (non-printing
characters appear as periods).
The autoscroll keys will scroll the dump forwards or backwards. Paging
is also possible by typing M<RETURN>.
The hex field of dump can be edited, and memory will be updated after
a <RETURN> is typed on the edited line.
M 29000 2900C
>029000 3C 66 6E 6E 60 62 3C 00 :<FNN-B<.
>029008 46 41 49 54 20 4C 55 58 :FAIT LUX
COMMAND: R
PURPOSE: Display "shadow" 4502 registers. The PC (address),
SR (status), A,X,Y,Z registers, and SP (stack pointer)
are displayed.
SYNTAX: R
R
PC SR AC XR YR SP
; BA1234 00 00 00 00 FB
The address field contains the 8-bit bank plus the 16-bit segment
address. The register dump can be edited by changing any field and
pressing return. The data is used by the G (JMP) and J (JSR) commands.
COMMAND: S
PURPOSE: Save a section of memory in a disk file.
SYNTAX: S <"filename">,<device>,<address_1>,<address_2>
<"filename"> Is a filename in quotes.
<address_1> Starting address of memory to be saved.
<address_2> Ending address PLUS ONE of memory to be saved.
The SAVE command creates a PRG (program) type file and copies data
into it from the specified memory area. All parameters are required.
S "filename",8,A0000,AFFFF
Saves expansion bank A in "filename" on drive 8 (you must specify
decimal for the drive number, or use hex equivalent). The last byte
at $FFFF will not be saved. Note that spaces between parameters after
the filename are not permitted. The 16-bit segment address is saved
as the first two bytes of the file, but the BANK address is not saved.
The BANK wraps automatically to the next higher bank number, but note
that LOAD is restricted to one bank, 64K bytes maximum.
COMMAND: T
PURPOSE: Transfer (copy) memory from one memory area to another
SYNTAX: T <address_1> <address_2> <address_3>
<address_1> Starting address of data to be copied.
<address_2> Ending address of data to be copied.
<address_3> Starting address of new location to copy data to.
Data can be copied forwards or backwards to any location, even within
the source range (eg., shift data up or down one byte) without any
problem. An automatic compare is performed for each byte, and
mismatches displayed on the screen.
Because of the compare feature, it's not recommended you use the T
command to copy data into write-only registers (the palette, for
example). It works, but all the compares will fail.
T 32000 3BFFF 82000
Copies BASIC ROM area to expansion RAM.
COMMAND: V
PURPOSE: Verify (compare) a disk file with the memory contents.
SYNTAX: V <"filename"> [,device [,load_address] ]
<"filename"> Is a filename in quotes.
[device] Is a number indicating the device the file is on.
[load_address] Optional load address. If not given, the file is
compared to memory at the 16-bit address stored on
disk (always RAM bank 0).
The Verify command causes a file to be read and compared to memory. If
the load address (including BANK) is given, the data read is
compared to data there. Otherwise the data read is compared to RAM
bank 0 at the 16-bit load address specified by the first two bytes
of the PRG (program) type file. If there is a mismatch, the message
'VERIFYING ERROR' is displayed. If the data matches, nothing is
displayed. An error occurs if the compare address overflows the
specified bank.
V "filename"
Compares "filename" from the default system drive to RAM bank 0 at the
address read from the file.
V "filename",+10,80000
Compares "filename" from drive 10 (notice you must specify decimal for
the drive number, or use hex equivalent) to expansion memory bank 8 at
address $0000. Note that spaces between parameters after the
filename are not permitted.
COMMAND: X
PURPOSE: Exit to BASIC
SYNTAX: X
COMMAND: > (greater than)
PURPOSE: Pokes data (1 to 16 bytes) into memory
SYNTAX: > <address> [byte]...
<address> Address to start "poking" or displaying
[byte] Data to be "poked". If not given, nothing is changed
and the memory at that location is "peeked".
Successive bytes are poked into successive locations.
COMMAND: @ (at sign)
PURPOSE: Disk operation: send command, display directory,status
SYNTAX: @ [device] [,command]
[device] Disk device number
[command] Optional command (see DOS manual for specific commands)
This command can be used to read a drive's status message, send a
drive a DOS command, or display a disk directory.
@ displays status of default system drive
@9 displays status of drive 9
@+10 or @A displays status of drive 10
@,$ displays directory of default drive
@9,$ displays status of drive 9
@,S0:*=SEQ displays all SEQ type files
@,S0:FILE sends command to delete file "FILE"
3.3. EDITOR
3.3.1. EDITOR ESCAPE SEQUENCES
This section contains a definition of the escape sequences that are
present in the C64DX and a brief description of what each does.
ESCape sequences are given by hitting the <ESCAPE> key and then
another key. In PRINT strings, escape sequences are given by
printing the escape character CHR$(27) followed by another character.
In either case, the "other" character is defined as one of the
following:
KEY FUNCTION
--- ----------------------------------------------------
@ Clear from cursor to end of screen
A Enable auto-insert mode
B Set bottom of screen window at cursor position
C Disable auto-insert mode (set overwrite mode)
D Delete current line
E Set cursor to non-flashing mode
F Set cursor to flashing mode
G Enable bell (control-G)
H Disable bell
I Insert line
J Move to start of current line
K Move to end of current line
L Enable scrolling
M Disable scrolling
N Normal screen fields [not implemented on C64DX]
O Cancel insert, quote, reverse, underline & flash modes
P Erase from cursor to start of current line
Q Erase from cursor to end of current line
R Set screen to reverse video [not implemented on C64DX]
S Set bold attribute (VIC-III colors 16-31)
T Set top of screen window at cursor position
U Unset bold attibute
V Scroll up
W Scroll down
X Swap 40/80 column display output device
Y Set default tab stops (8 spaces)
Z Clear all tab stops
[ Set monochrome display (disable attributes)
/ Cancel insert, quote, rvs, ul & flash modes
] Set color display (enable attributes)
3.3.2. EDITOR CONTROL CODES
This section contains a definition of the control codes that are
present in the C64DX and a brief description of what each does.
Control codes are given by pressing the <CTRL> key at the same time as
another key. In PRINT strings, control codes are given by printing the
control character with the CHRS() function. Control codes appear
within quoted strings as reverse field characters. In any case, the
control characters are:
CHR$ KEYBOARD
VALUE CONTROL FUNCTION
----- -------- ----------------------------------------------
2 B Underline on
7 G Bell tone
9 I Forward TAB
10 J Line feed
11 K Disable case change <shift>C= key (was code 9)
12 L Enable case change <shift>C= key (was code 8)
14 N Set display upper/lower case mode
15 O Flash on
17 Q Cursor down
18 R Reverse on
19 S Home cursor
20 T Delete previous character
21 U Backup word
23 W Advance word
24 X Tab set/clear
26 Z Backup TAB
27 [ Escape character
29 ] Cursor right
Shifted codes
---------------------------------------------------------------------
130 Underline off
142 Set uppercase/graphic mode
143 Flash off
145 Cursor up
146 Reverse mode off
147 Clear screen
148 Insert one character
157 Cursor left
Color codes
---------------------------------------------------------------------
5 white
28 red
30 green
31 blue
129 orange
144 black
149 brown
150 light red
151 light gray
152 medium gray
153 light green
154 light blue
155 dark gray
156 purple
158 yellow
159 cyan
Function keys
----------------------------------------------------------------
3 Stop
16 F9
21 F10
22 F11
23 F12
25 F13
26 F14
131 Run
132 Help
133 F1
134 F3
135 F5
136 F7
137 F2
138 F4
139 F6
140 F8
3.4. KEKNEL
3.4.1. C64DX KERNEL ENTRY POINTS
[*** THE FOLLOWING VECTORS AND JUMP TABLES ARE NOT FINAL ***]
Where the default indirect vectors point to:
FF09 nirq ;IRQ handler
FF0B monitor_brk ;BRK handler (Monitor)
FF0D nnmi ;NMI handler
FF0F nopen ;open
FF11 nclose ;close
FF13 nchkin ;chkin
FF15 nckout ;ckout
FF17 nclrch ;clrch
FF19 nbasin ;basin
FF1B nbsout ;bsout
FF1D nstop ;stop key scan
FF1F ngetin ;getin
FF21 nclall ;clall
FF23 monitor_parser ;monitor command parser
FF25 nload ;load
FF27 nsave ;save
FF29 talk ;Low level serial bus routines
FF2B listen
FF2D talksa
FF2F second
FF31 acptr
FF33 ciout
FF35 untalk
FF37 unlisten
FF39 DOS_talk ;newDOS routines
FF3B DOS_listen
FF3D DOS_talksa
FF3F DOS_second
FF41 DOS_acptr
FF43 DOS_ciout
FF45 DOS_untalk
FF47 DOS_unlisten
FF49 Get_DOS
FF4B Leave_DOS
FF4D jmp spin_spout ;setup fast serial port for input or output
FF50 jmp close_all ;close all logical files for a given device
FF53 jmp c64mode ;reconfigure system as a c/64 (no return!)
FF56 jmp monitor_call ;map in Monitor & call it
FF59 jmp bootsys ;boot alternate system from disk
FF5C jmp phoenix ;call cold start routines, disk boot loader
FF5F jmp lkupla ;search tables for given la
FF62 jmp lkupsa ;search tables for given sa
FF65 jmp swapper ;swap to alternate display device
FF68 jmp pfkey ;program function key
FF6B jmp setbnk ;set bank for load/save/verify/open
FF6E jmp jsr_far ;JSR to any bank, RTS to calling bank
FF71 jmp jmp_far ;JMP to any bank
FF74 jmp lda_far ;LDA (X),Y from bank Z
FF77 jmp sta_far :STA (X),Y to bank Z
FF7A jmp cmp_far ;CMP (X),Y to bank Z
FF7D jmp primm ;print immediate (always JSR to this routine!)
FF80 <FF> ;release number of C65 Kernel ($FF=not released)
FF81 jmp cint ;init screen editor & display chips
FF84 jmp ioinit ;init I/O devices (ports, timers, etc.)
FF87 jmp ramtas ;initialize RAM for system
FF8A jmp restor ;restore vectors to initial system
FF8D jmp vector ;change vectors for user
FF90 jmp setmsg ;control OS messages
FF93 jmp (isecond) ;send sa after listen
FF96 jmp (italksa) ;send sa after talk
FF99 jmp memtop ;set/read top of memory
FF9C jmp membot ;set/read bottom of memory
FF9F jmp key ;scan keyboard
FFA2 jmp settmo ;old IEEE set timeout value
FFA5 jmp (iacptr) ;read a byte from active serial bus talker
FFA8 jmp (iciout) ;send a byte to active serial bus listener
FFAB jmp (iuntalk) ;command serial bus device to stop talking
FFAE jmp (iunlisten) ;command serial bus device to stop listening
FFB1 jmp (ilisten) ;command serial bus device to listen
FFB4 jmp (italk) ;command serial bus device to talk
FFB7 jmp readss ;return I/O status byte
FFBA jmp setlfs ;set la, fa, sa
FFBD jmp setnam ;set length and fn adr
FFC0 jmp (iopen) ;open logical file
FFC3 jmp (iclose) ;close logical file
FFC6 jmp (ichkin) ;open channel in
FFC9 jmp (ickout) ;open channel out
FFCC jmp (iclrch) ;close I/O channel
FFCF jmp (ibasin) ;input from channel
FFD2 jmp (ibsout) ;output to channel
FFD5 jmp load ;load from file
FFD8 jmp save ;save to file
FFDB jmp Set Time ;set internal clock
FFDE jmp Read Time :read internal clock
FFE1 jmp (istop) ;scan stop key
FFE4 jmp (igetin) ;get char from queue
FFE7 jmp (iclall) ;clear all logical files (see close all)
FFEA jmp ScanStopKey ;(was increment clock) & scan stop key
FFED jmp scrorg ;return current screen window size
FFF0 jmp plot ;read/set x,y coord
FFF3 jmp iobase ;return I/O base
FFF6 c65mode ;C64/C65 interface
FFF8 c65mode
FFFA nmi ;processor hardware vectors
FFFC reset
FFFE irq_kernel
3.4.2. C64DX EDITOR JUMP TABLE
[*** THE FOLLOWING VECTORS AND JUMP TABLES ARE NOT FINAL ***]
E000 cint ;initialize editor & screen
E003 disply ;display character in .a, color in .x
E006 lp2 ;get a key from IRQ buffer into .a
E009 loopS ;get a chr from screen line into .a
E00C print ;print character in .a
E00F scrorg ;get size of window (rows,cols) in .x, .y
E012 keyboard_scan ;scan keyboard subroutine
E015 repeat ;repeat key logic & CKIT2 to store decoded key
E018 plot ;read or set (.c) cursor position in .x, .y
E01B mouse_cmd ;install/remove mouse driver
E01E escape ;execute escape function using chr in .a
E021 keyset ;redefine a programmable function key
E024 editor_irq ;IRQ entry
E027 palette_init ;initialize VIC palette
E02A swap ;40/80 mode change
E02D window ;set top left or bottom right (.c) of window
E030 cursor ;turn on or off (.c) soft cursor
3.4.3. C64DX BASIC JUMP TABLE
[*** THE FOLLOWING VECTORS AND JUMP TABLES ARE NOT FINAL ***]
Format Conversions
7F00 ayint ;convert floating point to integer
7F03 givayf ;convert integer to floating point.
7F06 fout ;convert floating point to ASCII string
7F09 val_1 ;convert ASCII string to floating point
7F0C getadr ;convert floating point to an address
7F0F floatc ;convert address to floating point
Math Functions
7F12 fsub ;MEM - FACC
7F15 fsubt ;ARG - FACC
7F18 fadd ;MEM + FACC
7F1B faddt ;ARG - FACC
7F1E fmult ;MEM * FACC
7F21 fmultt ;ARG * FACC
7F24 fdiv ;MEM / FACC
7F27 fdivt ;ARG / FACC
7F2A log ;compute natural log of FACC
7F2D int ;perform BASIC INT() on FACC
7F30 sqr ;compute square root of FACC
7F33 negop ;negate FACC
7F36 fpwr ;raise ARG to the MEM power
7F39 fpwrt ;raise ARG to the FACC power
7F3C exp ;compute EXP of FACC
7F3F cos ;compute COS of FACC
7F42 sin ;compute SIN of FACC
7F45 tan ;compute TAN of FACC
7F48 atn ;compute ATN of FACC
7F4B round ;round FACC
7F4E abs ;absolute value of FACC
7F51 sign ;test sign of FACC
7F54 fcomp ;compare FACC with MEM
7F57 rnd_0 ;generate random floating point number
Movement
7F5A conupk ;move RAM MEM to ARG
7F5D romupk ;move ROM MEM to ARG
7F60 movfrm :move RAM MEM to FACC
7F63 movfm :move ROM MEM to FACC
7F66 movmf :move FACC to MEM
7F69 movfa ;move ARG to FACC
7F6C movaf ;move FACC to ARG
7F6F run
7F72 runc
7F75 clear
7F78 new
7F7B link_program
7F7E crunch
7F81 FindLine
7F84 newstt
7F87 eval
7F8A frmevl
7F8D run_a_program
7F90 setexc
7F93 linget
7F96 garba2
7F99 execute_a_line
7F9C chrget
7F9F chrgot
7FA2 chkcom
7FAS frmnum
7FA8 getadr
7FAB getnum
7FAE getbyt
7FB1 plsv
Graphic Jump Table
8000 init ;Graphics BASIC init (same as command=0)
8002 parse ;Graphics BASIC command parser
8003 start ;0 commands
8006 screendef ;1
8008 screenopen ;2
800A screenclose ;3
800C screenclear ;4
800E screen ;5
8010 setpen ;6
8012 setpalette ;7
8014 setdmode ;8
8016 setdpat ;9
8018 line ;10
801A box ;11
801C circle ;12
801E polygon ;13
8020 ellipse ;14
8022 viewpclr ;15
8024 copy ;16
8026 cut ;17
8028 paste ;18
802A load ;19
802C char ;20
802E viewportdef ;21
3.4.4. C64DX SOFT VECTORS
[*** THE FOLLOWING VECTORS AND JUMP TABLES ARE NOT FINAL ***]
BASIC indirect vectors
02F7 jmp USR ;USR vector (must be set by application)
02FC esc_fn_vec ;Escape Function vector
02FE graphic_vector ;Graphic Kernel vector
0300 ierror ;indirect error (output error in .x)
0302 imain ;indirect main (system direct loop)
0304 icrnch ;indirect crunch (tokenization routine)
0306 iqplop ;indirect list (char list)
0308 igone ;indirect gone (char dispatch)
030A ieval ;indirect eval (symbol evaluation)
030C iesclk ;escape token crunch
030E iescpr ;escape token list
0310 iescex ;escape token execute
Kernel indirect vectors
02FA iAutoScroll ;AutoScroll used by BASIC, Monitor, Editor
0312 itime ;(unused)
0314 iirq ;IRQ
0316 ibrk ;BRK
0318 inmi ;NMI
031A iopen
031C iclose
031E ichkin
0320 ickout
0322 iclrch
0324 ibasin
0326 ibsout
0328 istop
032A igetin
032C iclall
032E exmon ;Monitor command indirect
0330 iload
0332 isave
Editor indirect vectors to routines & tables
0334 ctlvec ;'contrl' characters
0336 shfvec ;'shiftd' characters
0338 escvec ;'escape' characters
033A keyvec ;post keyscan, pre-evaluation of keys
033C keychk ;post-evaluation, pre-buffering of keys
033E decode ;vectors to 6 keyboard matrix decode tables
33E - Mode 1 --> normal keys
340 - Mode 2 --> <SHIFT> keys
342 - Mode 3 --> <C=> keys
344 - Mode 4 --> <CONTROL> keys
346 - Mode 5 --> <CAPS LOCK> keys
348 - Mode 6 --> <ALT> keys
3.4.5. KERNEL DOCUMENTATION
The KERNEL is the ROM resident operating system of the Commodore 64DX
computer. All input, output, and memory management is controlled by
the KERNEL. The KERNEL JUMP TABLE provides a standardized interface to
many useful routines within the operating system. Application
programmers are encouraged to utilize the JUMP TABLEs to simplify
their operations and guarantee their functionality should hardware or,
software modifications to the system become necessary.
C64 STANDARD KERNEL CALLS
The following system calls comprise the set of standard C64 system
calls for the C64 class of machines, including the PLUS-4. Several of
the calls, however function somewhat differently or may require
slightly different setups. This was necessary to accommodate specific
features of the system, notably the 40/80 column windowing Editor and
banked memory facilities. As with all Kernel calls, the system
configuration (BANK $FF) must be in context at the time of the call.
C64DX KERNEL JUMP TABLE DESCRIPTIONS
1. $FF81 CINT ; initialize screen editor
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
.Y used
Memory: init Editor RAM
init Editor I/O
Flags: none
Example:
SEI
JSR $FF81 ; initialize screen editor
CLI
CINT is the Editor's initialization routine. Editor indirect vectors
installed, programmable key definitions assigned, and the ASC/DIN key
scanned for NATIONAL keyboard/charset determination. CINT sets the VIC
bank, VIC nybble bank, enables the character ROM, resets SID volume,
and clears the screen. The only thing it does not do that pertains to
the Editor which is needed for IRQs (keyscan, VIC cursor blink, split
screen modes), key lines, screen background colors, etc. (see IOINIT).
Because CINT updates Editor indirect vectors that are used during IRQ
processing, you should disable IRQs prior to calling it. CINT utilizes
the status byte INIT STATUS as follows:
$1104 bit 6 = 0 --> Full initialization.
(Set INIT_STATUS bit 6)
= 1 --> Partial initialization.
(not keymatrix pointers)
(not program key definitions)
2. $FF84 IOINIT ; init I/O devices
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
.Y used
Memory: initialize I/O
Flags: none
Example:
SEI
JSR $FF84 ; initialize system I/O
CLI
IOINIT is perhaps the major function of the Reset handler. It
initializes both CIA's (timers, keyboard serial port, user port), the
4510 port, the VIC chip, the UART and the DOS. It distinguishes a PAL
system from an NTSC one and sets PALCNT if PAL. The system IRQ source,
the VIC raster, is started (pending IRQs are cleared). IOINIT utilizes
the status byte INIT STATUS as follows:
$1104 bit 7 = 0 --> Full initialization.
(set INIT STATUS bit 7)
= 1 --> Partial initialization.
You should be sure IRQs are disabled before calling IOINIT to avoid
interrupts while the various I/O devices are being initialized.
3. $FF87 RAMTAS ; init RAM and buffers
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
.Y used
Memory: initializes RAM
Flags: none
Example:
JSR $FF87 ; initialize system RAM
RAMTAS clears all base page RAM, allocates the sets pointers to the
top and bottom of system RAM and points the SYSTEM_VECTOR to BASIC
cold start. Lastly it sets a flag, DEJAVU, to indicate to other
routines that system RAM has been initialized and that the
SYSTEM_VECTOR is valid. It should be noted that the C64DX RAMTAS
routine does NOT in any way test RAM.
4. $FF8A RESTOR ; init Kernel indirects
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
.Y used
Memory: kernel indirects restored
Flags: none
Example:
SEI
JSR $FF8A ; restore kernel indirects
CLI
RESTOR restores the default values of all the Kernel indirect vectors
from the Kernel ROM list. It does NOT affect any other vectors, such
as those used by the Editor (see CINT) and BASIC. Because it is
possible for an interrupt (IRQ or NMI) to occur during the updating of
the interrupt indirect vectors, you should disable interrupts prior to
calling RESTOR. See also the VECTOR call.
5. $FF8D VECTOR ; init or copy indirects
Preparation:
Registers: .X = adr (low) of user list
.Y = adr (high) of user list
Memory: system map
Flags: .C = 0 --> load Kernel vectors
.C = 1 --> copy Kernel vectors
Calls: none
Results:
Registers: .A used
.Y used
Memory: as per call
Flags: none
Example:
LDX #save_lo
LDY #save_hi
SEC
JSR $FF87 ; copy indirects to 'save'
VECTOR reads or writes the Kernel RAM indirect vectors. Calling VECTOR
with the carry status set stores the current contents of the indirect
vectors to the RAM address passed in the .X and .Y registers (to the
current RAM bank). Calling VECTOR with the carry status clear updates
the Kernel indirect vectors from the user list passed in the .X and .Y
registers (from the current RAM bank). Interrupts (IRQ and NMI) should
be disabled when updating the indirects. See also the RESTOR call.
6. $FF90 SETMSG ; kernel messages on/off
Preparation:
Registers: .A = message control
Memory: system map
Flags: none
Calls: none
Results:
Registers: none
Memory: MSGFLG updated
Flags: none
Example:
LDA #0
JSR $FF90 ; turn OFF all Kernel messages
SETMSG updates the Kernel message flag byte MSGFLG which determines
whether system error and/or control messages will be displayed. BASIC
normally disables error messages always and disables control messages
in 'run' mode. Note that the Kernel error messages are not the verbose
ones printed by BASIC, but simply the 'I/O ERROR #' message that you
see when in the Monitor, for example. Examples of Kernel control
messages are 'LOADING' and 'FOUND'. The MSGFLG control bits are:
MSGFLG bit 7 = 1 --> enable CONTROL messages
bit 6 = 1 --> enable ERROR messages
7. $FF93 SECND ; serial: send SA after LISTN
Preparation:
Registers: .A = SA (secondary address)
Memory: system map
Flags: none
Calls: LISTN
Results:
Registers: .A used
Memory: STATUS ($90)
Flags: none
Example:
LDA #8
JSR $FFB1 ; LISTN device 8
LDA #15
JSR $FF93 ; pass it SA #15
SECND is a low-level serial routine used to send a secondary address
(SA) to a LISTeNing device (see LISTN Kernel call). An SA is usually
used to provide setup information to a device before the actual data
I/O operation begins. Attention is released after a call to SECND.
SECND is not used to send an SA to a TALKing device (see TKSA). (Most
applications should use the higher level I/O routines: see OPEN and
CKOUT).
8. $FF96 TKSA ; serial: send SA after TALK
Preparation:
Registers: .A = SA (secondary address)
Memory: system map
Flags: none
Calls: TALK
Results:
Registers: .A used
Memory: STATUS ($90)
Flags: none
Example:
LDA #8
JSR $FFB4 ; TALK device 8
LDA #15
JSR $FF93 ; pass it SA #15
TKSA is a low-level serial routine used to send a secondary address
(SA) to a device commanded to TALK (see TALK Kernel call). An SA is
usually used to provide setup information to a device before the
actual data I/O operation begins. (Most applications should use the
higher level I/O routines: see OPEN and CHKIN).
9. $FF99 MEMTOP ; set/read top of system RAM
Preparation:
Registers: .X = lsb of MEMSIZ
.Y = msb of MEMSIZ
Memory: system map
Flags: .C = 0 --> set top of memory
.C = 1 --> read top of memory
Calls: none
Results:
Registers: .X = lsb of MEMSIZ
.Y = msb of MEMSIZ
Memory: MEMSIZ
Flags: none
Example:
SEC
JSR $FF99 ; get top of user RAM
DEY
CLC
JSR $FF99 ; lower it 1 block
MEMTOP is used to read or set the top of system RAM, pointed to by
MEMSIZ. This call is included in the C64DX for completeness, but
neither the Kernel nor BASIC utilize MEMTOP as it has little meaning
in the banked memory environment of the computer (even the RS-232
buffers are permanently allocated). None-the-less, set the carry
status to load MEMSIZ into .X and .Y, and clear it to update the
pointer from .X and .Y. Note that MEMSIZ references only system RAM.
The Kernel initially sets MEMSIZ to $FF00.
10. $FF9C MEMBOT ; set/read bottom of system RAM
Preparation:
Registers: .X = lsb of MEMSTR
.Y = msb of MEMSTR
Memory: system map
Flags: .C = 0 --> set bot of memory
.C = 1 --> read bot of memory
Calls: none
Results:
Registers: .X = lsb of MEMSTR
.Y = msb of MEMSTR
Memory: MEMSTR
Flags: none
Example:
SEC
JSR $FF9C ; get bottom of user RAM_0
INY
CLC
JSR $FF9C ; raise it 1 block
MEMBOT is used to read or set the bottom of system RAM, pointed to by
MEMSTR. This call is included in the C64DX for completeness, but
neither the Kernel nor BASIC utilize MEMBOT as it has little meaning
in the banked memory environment of the C64DX. None-the-less, set the
carry status to load MEMSTR into .X and .Y, and clear it to update the
pointer from .X and .Y. Note that MEMSTR references only system RAM.
The Kernel initially sets MEMSTR to $2000 (BASIC text starts here).
11. $FF9F KEY ; scan keyboard
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: none
Memory: keyboard buffer
keyboard flags
Flags: none
Example:
JSR $FF9F ; scan the keyboard
KEY is an Editor routine which scans the entire keyboard. It
distinguishes between shifted and unshifted keys, control keys, and
programmable keys, setting keyboard status bytes and managing the
keyboard buffer. After decoding the key, KEY will manage such features
as toggling cases, pauses or delays, and key repeats. It is normally
called by the operating system during the 60Hz IRQ processing. Upon
conclusion, KEY leaves the keyboard hardware driving the key-line on
which the STOP key is located.
There are two indirect RAM jumps encountered during a keyscan: KEYVEC
($33A) and KEYCHK ($33C). KEYVEC (alias KEYLOG) is taken whenever a
key depression is discovered, before the key in .A has been decoded.
KEYCHK is taken after the key has been decoded, just before putting it
into the key buffer. KEYCHK carries the ASCII character in .A, the
keycode in .Y, and the shift-key status in .X.
The keyboard decode matrices are addressed via indirect RAM vectors as
well, located at DECODE.
12. $FFA2 SETTMO ; (reserved)
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: none
Memory: TIMOUT
Flags: none
Example:
LDA #value
JSR $FFA2 ; update TIMOUT byte
SETTMO is unused in the C64DX and is included for compatibility and
completeness. It is used in the C64 by the IEEE communication
cartridge to disable I/O timeouts.
13. $FFA5 ACPTR ; serial: byte input.
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: TALK
TKSA (if necessary)
Results:
Registers: .A = data byte
Memory: STATUS ($90)
Flags: none
Example:
JSR $FFA5 ; input a byte from serial bus
STA data
ACPTR is a low-level serial I/O utility to accept a single byte from
the current serial bus TALKer using full handshaking. To prepare for
this routine a device must first have been established as a TALKer
(see TALK) and passed a secondary address if necessary (see TKSA). The
byte is returned in .A. (Most applications should use the higher level
I/O routines: see BASIN and GETIN).
14. $FFA8 CIOUT ; serial: byte output
Preparation:
Registers: .A = data byte
Memory: system map
Flags: none
Calls: LISTN
SECND (if necessary)
Results:
Registers: .A used
Memory: STATUS ($90)
Flags: none
Example:
LDA data
JSR $FFA8 ; send a byte via serial bus
CIOUT is a low-level serial I/O utility to transmit a single byte to
the current serial bus LISTNer using full handshaking. To prepare for
this routine a device must first have been established as a LISTNer
(see LISTN) and passed a secondary address if necessary (see SECND).
The byte is passed in .A. Serial output data is buffered by one
character, with the last character being transmitted with EOI after a
call to UNLSN. (Most applications should use the higher level I/O
routines; see BSOUT).
15. $FFAB UNTLK ; serial: send untalk
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
Memory: STATUS ($90)
Flags: none
Example:
JSR $FFAB ; UNTALK serial device
UNTLK is a low-level Kernel serial bus routine that sends an UNTALK
command to all serial bus devices. It commands all TALKing devices to
stop sending data. (Most applications should use the higher level I/O
routines; see CLRCH).
16. $FFAE UNLSN ; serial: send unlisten
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
Memory: STATUS ($90)
Flags: none
Example:
JSR $FFAE ; UNLISTEN serial device
UNLSN is a low-level Kernel serial bus routine that sends an UNLISTEN
command to all serial bus devices. It commands all LISTENing devices
to stop reading data. (Most applications should use the higher level
I/O routines; see CLRCH).
17. $FFB1 LISTN ; serial: send listen command
Preparation:
Registers: .A = device (0-31)
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
Memory: STATUS ($90)
Flags: none
Example:
JSR $FFB1 ; command device to LISTEN
LISTN is a low-level Kernel serial bus routine that sends an LISTEN
command to the serial bus device in .A. It commands the device to
start reading data. (Most applications should use the higher level I/O
routines; see CKOUT).
18. $FFB4 TALK ; serial: send talk command
Preparation:
Registers: .A = device (0-31)
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
Memory: STATUS ($90)
Flags: none
Example:
JSR $FFB4 ; command device to TALK
TALK is a low-level Kernel serial bus routine that sends an TALK
command to the serial bus device in .A. It commands the device to
start sending data. (Most applications should use the higher level I/O
routines; see CHKIN).
19. $FFB7 READSS ; read I/O status byte
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A = STATUS ($90 or $A6)
Memory: STATUS cleared if RS-232 ($A6)
Flags: none
Example:
JSR $FFB7 ; STATUS for last I/O
READSS (alias READST) returns the status byte associated with the last
I/O operation (serial or RS-232) performed. Serial bus and newDOS
devices update STATUS ($90) and RS-232 I/O updates RSSTAT ($A6). Note
that, to simulate an 6551, RSSTAT is cleared after it is read via
READSS. The last I/O operation is determined by the contents of FA
($BA), thus applications which drive I/O devices using the lower-level
Kernel calls should not use READSS.
20. $FFBA SETLFS ; set channel LA, FA, SA
Preparation:
Registers: .A = LA (logical #)
.X = FA (device #)
.Y = SA (secondary adr)
Memory: system map
Flags: none
Calls: none
Results:
Registers: none
Memory: LA, FA, SA updated
Example:
see OPEN
SETLFS sets the logical file number (LA, $B8), device number (FA,
$BA), and secondary address (SA, $B9) for the higher-level Kernel I/O
routines. The LA must be unique among OPENed files and is used to
identify specific files for I/O operations. The device number range is
0 to 31 and is used to target I/O. The SA is a command to be sent to
the indicated device, usually to place it in a particular mode. If the
SA is not needed, the .Y register should pass $FF. SETLFS is often
used along with SETNAM and SETBNK calls prior to OPENs. See the Kernel
OPEN, LOAD, and SAVE calls for examples.
21. $FFBD SETNAM ; set filename pointers
Preparation:
Registers: .A = string length
.X = string adr_low
.Y = string adr_high
Memory: system map
Flags: none
Calls: SETBNK
Results:
Registers: none
Memory: FNLEN, FNADR updated
Flags: none
Example:
see OPEN
SETNAM sets up the filename or command string for higher-level Kernel
I/O calls such as OPEN, LOAD, and SAVE. The string (filename or
command) length is passed in .A and updates FNLEN ($B7). The address
of the string is passed in .X (low) and Y (high). See the companion
call, SETBNK which specifies which RAM bank the string is found. If
there is no string, SETNAM should still be called and a null ($00)
length specified (the address does not matter). SETNAM is often used
along with SETBNK and SETLFS calls prior to OPENs. See the Kernel
OPEN, LOAD, and SAVE calls for examples.
22. $FFC0 OPEN ; open logical file
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: SETLFS, SETNAM, SETBNK
Results:
Registers: .A = error code (if any)
.X used
.Y used
Memory: setup for I/O
STATUS, RSSTAT updated
Flags: .C = 1 --> error
Example: OPEN 1,8,15,"I0"
LDA #length ; fnlen
LDX #<filename ; fnadr (command)
LDY #>filename
JSR $FFBD ; SETNAM
LDX #0 ; fnbank (RAM_0)
JSR $FF68 ; SETBNK
LDA #1 ; la
LDX #8 ; fa
LDY #15 ; sa
JSR $FFBA ; SETLFS
JSR $FFC0 ; OPEN
BCS error
filename .BYTE 'I0'
length = 2
OPEN prepares a logical file for I/O operations. It creates a unique
entry in the Kernel logical file tables LAT ($362), FAT ($36C), and
SAT ($376) using its index LDTND ($98) and data supplied by the user
via SETLFS. There can be up to ten logical files OPENed
simultaneously. OPEN performs device specific opening tasks for
serial, RS-232, keyboard & screen, devices, including clearing the
previous status and transmitting any given filename or command string
supplied by the user via SETNAM and SETBNK. The I/O status will be
updated appropriately and can be read via READSS.
The path to OPEN is through an indirect RAM vector at $31A.
Applications may therefore provide their own OPEN procedures or
supplement the system's by re-directing this vector to their own
routine.
23. $FFC3 CLOSE ; close logical file
Preparation:
Registers: .A = LA (logical #)
Memory: system map
Flags: .C (see text below)
Calls: none
Results:
Registers: .A = error code (if any)
.X used
.Y used
Memory: logical tables updated
STATUS, RSSTAT updated
Flags: .C = 1 --> error
Example:
LDA #1 ; la
JSR $FFC3 ; CLOSE
BCS error
CLOSE removes the logical file (LA) passed in .A from the logical file
tables and performs device specific closing tasks. Keyboard, screen,
and any unOPENed files pass through. RS-232 devices are not closed
until all buffered data has been transmitted. Serial files are closed
by transmitting a 'close' command (if an SA was given when it was
opened), sending any, buffered character, and UNLiSTeNing the bus.
There is a special provision incorporated into the CLOSE routine of
systems featuring BASIC DOS command. If the following conditions are
all TRUE, a full CLOSE is NOT performed: the table entry is removed
but a 'close' command is NOT transmitted to the device. This allows
the disk command channel to be properly OPENed and CLOSEd without the
disk operating system closing ALL files on its end:
.C = 1 --> indicates special CLOSE
FA >=8 --> device is a disk
SA =15 --> command channel
The path to CLOSE is through an indirect RAM vector at $31C.
Applications may therefore provide their own CLOSE procedures or
supplement the system's by re-directing this vector to their own
routine.
24. $FFC6 CHKIN ; set input channel
Preparation:
Registers: .X = LA (logical #)
Memory: system map
Flags: none
Calls: OPEN
Results:
Registers: .A = error code (if any)
.X used
.Y used
Memory: LA, FA, SA, DFLTN
STATUS, RSSTAT updated
Flags: .C = 1 --> error
Example:
LDX #1 ; la
JSR $FFC6 ; CHKIN
BCS error
CHKIN establishes an input channel to the device associated with the
logical address (LA) passed in .X, in preparation for a call to BASIN
or GETIN. The Kernel variable DFLTN ($99) is updated to indicate the
current input device and the variables LA, FA, and SA are updated with
the file's parameters from its entry in the logical file tables (put
there by OPEN). CHKIN performs certain device specific tasks: screen
and keyboard channels pass through, and serial channels are sent a
TALK command and the SA transmitted (if necessary). Call CLRCH to
restore normal I/O channels.
CHKIN is required for all input except the keyboard. If keyboard input
is desired and no other input channel is established, you do not need
to call CHKIN or OPEN. The keyboard is the default input device for
BASIN and GETIN.
The path to CHKIN is through an indirect RAM vector at $31E.
Applications may therefore provide their own CHKIN procedures or
supplement the system's by re-directing this vector to their own
routine.
25. $FFC9 CKOUT ; set output channel
Preparation:
Registers: .X = LA (logical #)
Memory: system map
Flags: none
Calls: OPEN
Results:
Registers: .A = error code (if any)
.X used
.Y used
Memory: LA, FA, SA, DFLTO
STATUS, RSSTAT updated
Flags: .C = 1 --> error
Example:
LDX #1 ; la
JSR $FFC9 ; CKOUT
BCS error
CKOUT establishes an output channel to the device associated with the
logical address (LA) passed in .X, in preparation for a call to BSOUT.
The Kernel variable DFLTO ($9A) is updated to indicate the current
output device and the variables LA, FA, and SA are updated with the
file's parameters from its entry in the logical file tables (put there
by OPEN). CKOUT performs certain device specific tasks: keyboard
channels are illegal, screen channels pass through, and serial
channels are sent a LISTN command and the SA transmitted (if
necessary). Call CLRCH to restore normal I/O channels.
CKOUT is required for all output except the screen. If screen output
is desired and no other output channel is established, you do not need
to call CKOUT or OPEN. The screen is the default output device for
BSOUT.
The path to CKOUT is through an indirect RAM vector at $320.
Applications may therefore provide their own CKOUT procedures or
supplement the system's by re-directing this vector to their own
routine.
26. $FFCC CLRCH ; restore default channels
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
Memory: DFLTI, DFLTO updated
Flags: none
Example:
JSR $FFCC ; restore default I/O
CLRCH (alias CLRCHN) is used to clear all open channels and restore
the system default I/O channels after other channels have been
established via CHKIN and/or CHKOUT. The keyboard is the default input
device and the screen is the default output device. If the input
channel was to a serial device, CLRCH first UNTLKs it. If the output
channel was to a serial device, it is UNLiSteNed first.
The path to CLRCH is through an indirect RAM vector at $322.
Applications may therefore provide their own CLRCH procedures or
supplement the system's by re-directing this vector to their own
routine.
27. $FFCF BASIN ; input from channel
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: CHKIN (if necessary)
Results:
Registers: .A = character (or error code)
Memory: STATUS, RSSTAT updated
Flags: .C = 1 if error
Example:
LDY #0 ; index
more JSR $FFCF ; input a character
STA data,Y ; buffer it
INY
CMP #$0D ; carriage return?
BNE more
BASIN (alias CHRIN) reads a character from the current input device
(DFLTN, $99) and returns it in .A. Input from devices other than the
keyboard (the default input device) must be OPENed and CHKINed. The
character is read from the input buffer associated with the current
input channel:
1. RS-232 data is returned a character at a time from the RS-232 input
buffer, waiting until a character is received if necessary. If
RSSTAT is bad from a prior operation, input is skipped and null
input (carriage return) is substituted.
2. Serial data is returned a character at a time directly from the
serial bus, waiting until a character is sent if necessary. If
STATUS ($90) is bad from a prior operation, input is skipped and
null input (carriage return) is substituted.
3. Screen data is read from screen RAM starting at the current cursor
position and ending with a faked carriage return at the end of the
logical screen line.
4. Keyboard data is input by turning on the cursor reading characters
from the keyboard buffer and echoing them on the screen until a
carriage return is encountered. Characters are then returned one at
a time from the screen until all characters input have been passed,
including the carriage return. Any calls after the eol will start
the process over again.
The path to BASIN is through an indirect RAM vector at $324.
Applications may therefore provide their own BASIN procedures or
supplement the system's by re-directing this vector to their own
routine.
28. $FFD2 BSOUT ; output to channel
Preparation:
Registers: .A = character
Memory: system map
Flags: none
Calls: CKOUT (if necessary)
Results:
Registers: .A = error code (if any)
Memory: STATUS, RSSTAT updated
Flags: .C = 1 if error
Example:
LDA #character
JSR $FFD2 ; output a character
BSOUT (alias CHROUT) writes the character in .A to the current output
device (DFLTO, $9A). Output to devices other than the screen (the
default output device) must be OPENed and CKOUTed. The character is
written to the output buffer associated with the current output
channel:
1. RS-232 data is put a character at a time into the RS-232 output
buffer, waiting until there is room if necessary.
2. Serial data is passed to CIOUT which buffers one character and
sends the previous character.
3. Screen data is put into screen RAM at the current cursor position.
4. Keyboard output is illegal.
The path to BSOUT is through an indirect RAM vector at $326.
Applications may therefore provide their own BSOUT procedures or
supplement the system's by re-directing this vector to their own
routine.
29. $FFD5 LOAD ; load from file
Preparation:
Registers: .A = 0 --> LOAD
.A > 0 --> VERIFY
.X = load adr_lo (if SA=0)
.Y = load adr_hi (if SA=0)
Memory: system map
Flags: none
Calls: SETLFS, SETNAM, SETBNK
Results:
Registers: .A = error code (if any)
.X = ending adr_lo
.Y = ending adr_hi
Memory: per command
STATUS updated
Flags: .C = 1 --> error
Example: LOAD "program",8,1
LDA #length ; fnlen
LDX #<filename ; fnadr
LDY #>filename
JSR $FFBD ; SETNAM
LDA #0 ; load/verify bank (RAM_0)
LDX #0 ; fnbank (RAM_0)
JSR $FF68 ; SETBNK
LDA #0 ; la (not used)
LDX #8 ; fa
LDY #$FF ; sa (SA>0 normal load)
JSR $FFBA ; SETLFS
LDA #0 ; load, not verify
LDX #<load_adr ; (used only if SA=0)
LDY #>load_adr ; (used only if SA=0)
JSR $FFD5 ; LOAD
BCS error
STX end_lo
STY end_hi
filename .BYTE 'program'
length = 7
This routine LOADs data from an input device into memory. It can also
be used to VERIFY that data in memory matches that in a file. LOAD
performs device specific tasks for serial LOADs. You cannot LOAD from
RS-232 devices, the screen, or the keyboard. While LOAD performs all
the tasks of an OPEN, it does NOT create any logical files as an OPEN
does. Also note that LOAD cannot 'wrap' memory banks. As with any I/O,
the I/O status is updated appropriately and can be read via READSS.
LOAD has two options that the user must select:
1. LOAD vs. VERIFY: the contents of .A passed at the call to LOAD
determines which mode is in effect. If .A is zero, a LOAD operation
will be performed and memory will be overwritten. If .A is
non-zero, a VERIFY operation will be performed and the result
passed via the error mechanism.
2. LOAD ADDRESS: the secondary address (SA) setup by the call to
SETLFS determines where the LOAD starting address comes from. If
the SA is zero, the user wants the address in .X and .Y at the time
of the call to be used. If the SA is non-zero, the LOAD starting
address is read from the file header itself and the file loaded to
the same place from which it was SAVEd.
The serial LOAD routine automatically attempts to access a newDOS
drive, then attempts to BURST load a file, and resorts to the normal
load mechanism (but still using the FAST serial routines) if the BURST
handshake is not returned.
The path to LOAD is through an indirect RAM vector at $330.
Applications may therefore provide their own LOAD procedures or
supplement the system's by re-directing this vector to their own
routine.
30. $FFD8 SAVE ; save to file
Preparation:
Registers: .A = pointer to start adr
.X = end_adr_lo
.Y = end_adr_hi
Memory: system map
Flags: none
Calls: SETLFS, SETNAM, SETBNK
Results:
Registers: .A = error code (if any)
.X = used
.Y = used
Memory: STATUS updated
Flags: .C = 1 --> error
Example: SAVE "program",8
LDA #length ; fnlen
LDX #<filename ; fnadr
LDY #>filename
JSR $FFBD ; SETNAM
LDA #0 ; save from bank (RAM_0)
LDX #0 ; fnbank (RAM_0)
JSR $FF68 ; SETBNK
LDA #0 ; la (not used)
LDX #8 ; fa
LDY #0 ; sa (cassette only)
JSR $FFBA ; SETLFS
LDA #start ; pointer to start address
LDX end ; ending address lo
LDY end+1 ; ending address hi
JSR $FFD8 ; SAVE
BCS error
filename .BYTE 'program'
length = 7
start .WORD address1 ; page_0
end .WORD address2
This routine SAVEs data from memory to an output device. SAVE performs
device specific tasks for serial SAVEs. You cannot SAVE from RS-232
devices, the screen, or the keyboard. While SAVE performs all the
tasks of an OPEN, it does NOT create any logical files as an OPEN
does. The starting address of the area to be SAVEd must be placed in a
base-page vector and the address of this vector passed to SAVE in .A
at the time of the call. The address of the last byte to be SAVEd PLUS
ONE is passed in .X and .Y at the same time.
SAVE first attempts to access a newDOS drive. There is no BURST save:
the normal FAST serial routines are used. As with any I/O, the I/O
status will be updated appropriately and can be read via READSS.
The path to SAVE is through an indirect RAM vector at $332.
Applications may therefore provide their own SAVE procedures or
supplement the system's by re-directing this vector to their own
routine.
31. $FFDB SETTIM ; set internal clock
Preparation:
Registers: .A = hours
.X = minutes
.Y = seconds
.Z = tenths
Memory: system map
Flags: none
Calls: none
Results:
Registers: none
Memory: TOD at CIA $DC00 updated
Flags: none
Example:
LDA #0 ; reset clock
TAX
TAY
TAZ
JSR $FFDB ; SETTIM
SETTIM sets the system CIA 24-hour TOD clock, which counts tenths of a
second and automatically wraps at the 24-hour point.
32. $FFDE RDTIM ; read internal clock
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A = hours
.X = minutes
.Y = seconds
.Z = tenths
Memory: none
Flags: none
Example:
JSR $FFDE ; RDTIM
RDTIM reads the system CIA 24-hour TOD clock, which counts tenths of a
second. The timer is automatically wrapped at the 24-hour point.
33. $FFE1 STOP ; scan stop key
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A = last keyboard row
.X = used (if STOP key)
Memory: none
Flags: status valid
Example:
JSR $FFE1 ; scan STOP key
BEQ stop ; branch if down
STOP checks a Kernel variable STKEY ($91), which is updated by UDTIM
during normal IRQ processing and contains the last scan of keyboard
column C7. The STOP key is bit-7, which will be zero if the key is
down. If it is, default I/O channels are restored via CLRCH and the
keyboard queue is flushed by resetting NDX ($D0). The keys on keyboard
line C7 are:
bit: 7 6 5 4 3 2 1 0
key: STOP Q C= SPACE 2 CTRL <-- 1
The path to STOP is through an indirect RAM vector at $328.
Applications may therefore provide their own STOP procedures or
supplement the system's by re-directing this vector to their own
routine.
34. $FFE4 GETIN ; read buffered data
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: CHKIN (if necessary)
Results:
Registers: .A = character (or error code)
.X used
.Y used
Memory: STATUS, RSSTAT updated
Flags: .C = 1 if error
Example:
wait JSR $FFE4 ; get any key
BEQ wait
STA character
GETIN reads a character from the current input device (DFLTN $99)
buffer and returns it in .A. Input from devices other than the
keyboard (the default input device) must be OPENed and CHKINed. The
character is read from the input buffer associated with the current
input channel:
1. Keyboard input: a character is removed from the keyboard buffer and
passed in .A. If the buffer is empty, a null ($00) is returned.
2. RS-232 input: a character is removed from the RS-232 input buffer
and passed in .A. If the buffer is empty, a null ($00) is returned
(use READSS to check validity).
3. Serial input: GETIN automatically jumps to BASIN. See BASIN serial
I/O.
4. Screen input: GETIN automatically jumps to BASIN. See BASIN serial
I/O.
The path to GETIN is through an indirect RAM vector at $32A.
Applications may therefore provide their own GETIN procedures or
supplement the system's by re-directing this vector to their own
routine.
35. $FFE7 CLALL ; close all files and channels
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
Memory: LDTND, DFLTN, DFLTO updated
Flags: none
Example:
JSR $FFE7 ; close files
CLALL deletes all logical file table entries by resetting the table
index, LDTND ($98). It clears current serials channels (if any) and
restores the default I/O channels via CLRCH.
The path to CLALL is through an indirect RAM vector at $32C.
Applications may therefore provide their own CLALL procedures or
supplement the system's by re-directing this vector to their own
routine.
36. $FFEA ScanStopKey (was UDTIM, which has no purpose on C64DX)
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
Memory: TIME, TIMER, STKEY updated
Flags: none
Example:
JSR $FFEA ; ScanStopKey
Scans key line C7, on which the STOP key lies, and stores the result
in STKEY ($91). The Kernel routine STOP utilizes this variable.
37. $FFED SCRORG ; get current screen window size
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A = screen width
.X = window width
.Y = window height
Memory: none
Flags: none
Example:
JSR $FFED ; SCRORG
SCRORG returns active window's size (maximum row & column #) & origin.
entry: nothing required.
exit: .C = max. screen width (0=80, 1=40) default = 0
.X = max. column number (# columns - 1) default = 79
.Y = max. line number (# lines minus 1) default = 24
.A = window address (home position), low default = $0800
.Z = window address, high
38. $FFF0 PLOT ; read/set cursor position
Preparation:
Registers: .X = cursor line
.Y = cursor column
Memory: system map
Flags: .C = 0 --> set cursor position
.C = 1 --> get cursor position
Calls: none
Results:
Registers: .X = cursor line
.Y = cursor column
Memory: TBLX, PNTR updated
Flags: .C = 1 --> error
PLOT Reads or sets the cursor position within current window.
Entry: .C = 1 Returns the cursor position (.Y=column, .X=line)
relative to the current window origin (NOT screen
origin).
.C = 0 Sets the cursor position (.Y=column, .X=line)
relative to the current window origin (NOT screen
origin).
Exit: When reading position, .X=line, .Y=column, .C=1 if wrapped
line.
When setting new position, .X=line, .Y=column, and
.C = 0 Normal exit. The cursor has been moved to the position
contained in .X & .Y relative to window origin (see
SCRORG).
.C = 1 Error exit. The requested position was outside the
current window (see SCRORG). The cursor has not been
moved.
When called with the carry status set, PLOT returns the current cursor
position relative to the current window origin (NOT screen origin).
When called with the carry status clear, PLOT attempt to move the
cursor to the indicated line and column relative to the current window
origin (NOT screen origin). PLOT will return a clear carry status if
the cursor was moved, and a set carry status if the requested position
was outside the current window (NO CHANGE has been made).
Editor variables that are useful:
SCBOT - $E4 --> window bottom
SCTOP - $E5 --> window top
SCLF - $E6 --> window left side
SCRT - $E7 --> window right side
TBLX - $EC --> cursor line
PNTR - $ED --> cursor column
LINES - $EE --> maximum screen height
COLUMNS $EF --> maximum screen width
39. $FFF3 IOBASE ; read base address of I/O block
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .X = lsb of I/O block
.Y = msb of I/O block
Memory: none
Flags: none
Example:
JSR $FFF3 ; find the I/O block
IOBASE is unused in the C64DX and is included for compatibility and
completeness. It returns the address of the I/O block in .X and .Y.
NEW C64DX KERNEL CALLS
The following system calls comprise a set of extensions to the
standard CBM jump table. They are specifically for the C64DX machine
and as such should not be considered as permanent additions to the
standard jump table. With the exception of C64MODE they are all true
subroutines and will terminate via RTSs. As with all Kernel calls, the
system configuration (BANK $FF) must be in context at the time of the
call.
1. $FF4D SPIN_SPOUT ;setup fast serial ports for I/O
Preparation:
Registers: none
Memory: system map
Flags: .C = 0 --> select SPINP
.C = 1 --> select SPOUT
Calls: none
Results:
Registers: .A used
Memory: CIA_1, FSDIR register
Flags: none
Example:
CLC
JSR $FF4D ;setup for fast serial input
The fast serial protocol utilizes CIA_1 (6526 at $DC00) and a special
driver circuit controlled in part by the FSDIR register. SPINP and
SPOUT are routines used by the system to set up the CIA and fast
serial driver circuit for input or output. SPINP sets up CRA (CIA_1
register 14) and clears the FSDIR bit for input. SPOUT sets up CRA,
ICR (CIA_1 register 13), timer A (CIA_l registers 4 & 5), and sets the
FSDIR bit for output. Note the state of the TOD_IN bit of CRA is
always preserved. These routines are required only by applications
driving the fast serial bus themselves from the lowest level.
2. $FF50 CLOSE_ALL ;close all files on a device
Preparation:
Registers: .A --> device # (FA: 0-31)
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
.Y used
Memory: none
Flags: none
Example:
LDA #$08
JSR $FF50 ; close all files on device 8
The FAT is searched for the given FA. A proper CLOSE is
performed for all matches. If one of the CLOSEd channels is the
current I/O channel then the default channel is restored.
This call is utilized, for example, by the BASIC command DCLOSE.
3. $FF53 C64MODE ;reconfigure system as a C64
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: none
Memory: none
Flags: none
Example:
JMP $FF53 ;switch to C64 mode
THERE IS NO RETURN FROM THIS ROUTINE. The system downloads code to RAM
which reMAPs the system to put the C64 ROM in context, resets all
VIC-III modes, and jumps to the C64 start routine.
Return to C65 mode is by resetting the machine, although a program
could do it very easily. A vector on the C64 side is provided to
restart C64DX mode.
4. $FF56 MonitorCall ;enter Monitor mode
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: none
Memory: none
Flags: none
Turns off BASIC receipt of IRQ, maps BASIC out, maps the Monitor in,
and calls it.
When the Monitor is exited, the system is restored, BASIC mapped in,
and the system_vector taken (usually points to BASIC warm start
entry).
5. $FF59 BOOT_SYS ;boot an alternate OS from disk
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: undefined
Memory: undefined
Flags: undefined
Boot an alternate system. Reads the "home" sector of any diskette
(physical track 0 sector 1, 512 bytes) into memory at $00400, turns
off BASIC, and JMPs to it. Nothing done if disk not present. JMP not
made if first byte is not $4C.
It forces the "system" memory map, not user environment.
No support for C128-style BOOT sector. Not related to BASIC 10.0 BOOT
command, which RUNs a BASIC program called "AUTOBOOT.C65*" if found.
6. $FF5C PHOENIX ;???? C64DX diagnostics ????
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: undefined
Memory: undefined
Flags: none
Example:
JSR $FF5C ;PHOENIX
Not same thing as C128 Phoenix routine. In the C65 development system,
this routine is called after BASIC inits and performs some system
diagnostics, displaying results on the screen.
7. $FF5F LKUPLA ;search tables for given la
8. $FF62 LKUPSA ;search tables for given sa
Preparation:
Registers: .A = LA (logical file number)
if LKUPLA
.Y = SA (secondary address)
if LKUPSA
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A = LA (only if found)
.X = FA (only if found)
.Y = SA (only if found)
Memory: none
Flags: .C = 0 if found
.C = 1 if not found
Example:
LDY #$60 ;find an available SA
again INY
CPY #$6F
BCS too_many ;too many files open
JSR $FF62 ;LKUPSA
BCC again ;get another if in use
LKUPLA and LKUPSA are Kernel routines used primarily by BASIC DOS
commands to work around a user's open disk channels. The Kernel
requires unique logical device numbers (LAs) and the disk requires
unique secondary addresses (SAs), therefore BASIC must find
alternative unused values whenever it needs to establish a disk
channel.
9. $FF65 SWAPPER ;switch between 40 & 80 column modes
Preparation:
Registers: none
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
.Y used
Memory: screen cleared
Flags: none
Example:
LDA $D7 ;check display mode
BMI if_80 ;branch if 80 column
JSR $FF5F ;switch from 40 to 80
MODE, location $D7, is toggled by SWAPPER to indicate the current
display mode: $80 = 80-column, $00 = 40-column. Because they are both
VIC screens, changing them requires clearing the screens since they
share the same memory location.
10. $FF68 PFKEY ;program a function key
Preparation:
Registers: .A = pointer to string adr
(lo/hi/bank)
.Y = string length
.X = key number (1-16)
Memory: system map
Flags: none
Calls: none
Results:
Registers: .A used
.X used
.Y used
Memory: PKYBUF, PKYDEF tables updated
Flags: .C = 0 if successful
.C = 1 if no room
Example:
LDA #$FA ;pointer to string address
LDY #6 ;length
LDX #15 ;key # ('HELP' key)
JSR $FF68 ;install new key def'n
BCS no_room
>000FA 00 13 00 ;ptr to $1300 bank 0
>01300 53 54 52 49 4E 47 ;'string'
PFKEY (alias KEYSET) is an Editor utility to replace a function key
string with a user's string. Keys 1-14 are F1-F14, 15 is the HELP key,
and 16 is the <shift>RUN string. The example above replaces the
'help<cr>' string assigned at system initialization to the HELP key
with the string 'string'. Both the key length table, PKYBUF
($1000-$100F), and the definition area, PKYDEF ($1010-$10FF) are
compressed and updated. The maximum length of all 16 strings is 240
characters. No change is made if there is insufficient room for a new
definition.
11. $FF6B SETBNK ;set bank for I/O operations
;and filename
Preparation:
Registers: .A = BA, memory bank (0-FF)
.X = FNBANK, filename bank
Memory: system map
Flags: none
Calls: SETNAM
Results:
Registers: none
Memory: BA, FNBANK updated
Flags: none
Example:
see OPEN
SETBNK is a prerequisite for any memory I/O operations and must be
used along with SETLFS and SETNAM prior to OPENing files, etc. BA
($C6) sets the current 64KB memory bank for LOAD/SAVE/ VERIFY
operations. FNBANK ($C7) indicates the bank in which the filename
string is found. The Kernel routine SETBNK is often used along with
SETNAM and SETLFS calls prior to OPENs. See the Kernel OPEN, LOAD, and
SAVE calls for examples.
12. $FF6E JSRFAR ;gosub in another bank
13. $FF71 JMPFAR ;goto another bank
Preparation:
Registers: none
Memory: system map, also:
$02 --> bank (0-FF)
$03 --> PC_high
$04 --> PC_low
$05 --> .S (status)
$06 --> .A
$07 --> .X
$08 --> .Y
$09 --> .Z
Flags: none
Calls: none
Results:
Registers: none
Memory: as per call, also:
$05 --> .S (status)
$06 --> .A
$07 --> .X
$08 --> .Y
$09 --> .Z
Flags: none
The two routines, JSRFAR and JMPFAR, enable code executing in the
system bank of memory to call (or JMP to) a routine in any other bank.
In the case of JSRFAR, the called routine must restore the system map
before executing a return.
JSRFAR calls JMPFAR. Both are RAM routines, located at $39C and $3B1
respectively.
The user should take necessary precautions when calling a non-system
bank that interrupts (IRQs & NMIs) will be handled properly (or
disabled beforehand).
14. $FF74 LDA_FAR ;LDA (.X),Y from bank .Z
Preparation:
Registers: .X = pointer to base page pointer
.Y = index
.Z = bank (0-FF)
Memory: setup indirect vector
Flags: none
Calls: none
Results:
Registers: .A = data
Memory: DMA_LIST updated
Flags: status valid
LDA_FAR enables applications to read data from any other bank. It
builds a DMA_LIST to fetch one byte, executes the DMA, and reads the
byte. It's a ROM routine.
15. $FF77 STA_FAR ;STA (.X),Y from bank .Z
Preparation:
Registers: .A = data
.X = pointer to base page pointer
.Y = index
.Z = bank (0-FF)
Memory: setup indirect vector
Flags: none
Calls: none
Results:
Registers: .X used
Memory: DMA_LIST updated
Flags: status invalid
STA_FAR enables applications to write data to any other bank. It
builds a DMA_LIST to stash one byte, and executes the DMA. It's a ROM
routine.
16. $FF7A CMP_FAR ;CMP (.X),Y from bank .Z
Preparation:
Registers: .A = data
.X = pointer to a base page pointer
.Y = index
.Z = bank (0-FF)
Memory: setup indirect vector
Flags: none
Calls: none
Results:
Registers: .X used
Memory: none
Flags: status valid
CMP_FAR enables applications to compare data to any other bank. It
builds calls LDA_FAR and compares the given byte with the byte
fetched. It's a ROM routine.
17. $FF7D PRIMM ;print immediate utility
Preparation:
Registers: none
Memory: none
Flags: none
Calls: none
Results:
Registers: none
Memory: none
Flags: none
Example:
JSR $FF7D ;display following text
.BYTE 'message'
.BYTE $00 ;terminator
JMP continue ;execution resumes here
PRIMM is a Kernel utility used to print (to the default output device)
a PETSCII string which immediately follows the call. The string must
be no longer than 255 characters and be terminated by a null ($00)
character. It cannot contain any embedded null characters. Because
PRIMM uses the system stack to find the string and a return address,
you MUST NOT JMP to PRIMM. There must be a valid address on the stack.
3.4.6. BASIC 10.0 MATH PACKAGE
This document details the many user-callable routines available in the
C64DX BASIC 10.0 math package.
FLOATING POINT MATH PACKAGE CONVENTIONS
In BASIC memory the number is PACKED and looks like this:
+--------+---------+--------+--------+-----+
| signed | B7=SGN | | | |
| EXP +---------+ M A N T I S S A | LSB |
| +$80 | MSB | | | |
+--------+---------+--------+--------+-----+
Because the mantissa is normalized such that its msb is always 1,
BASIC stores the SIGN of the mantissa here to save a byte of
storage. It must be normalized when put in the FACC (see CONUPK). In
the FACC the NORMALIZED number looks like this:
$63 $64 $65 $66 $67 $68
FACEXP FACHO FACMOH FACMO FACLO FACSGN
+--------+---------+--------+--------+-----+-------+
| signed | BIT 7=1 | | | | SIGN |
| EXP +---------+ M A N T I S S A | LSB |+ = $00|
| +$80 | MSB | | | |- = $00|
+--------+---------+--------+--------+-----+-------+
Negative exponents are not stored 2's complement. The maximum exponent
is 10^38 ($FF) and the minimum is 10^-39 ($01). A zero value for the
exponent means the number is zero. Since the exponent is a power of 2,
it can be described as the number of left (EXP>$80) or right
(EXP<=$80) shifts to be performed on the normalized mantissa to create
the binary representation of the value. There is a second floating
accumulator called ARG which has the same layout. It is located at $6A
through $6F. Throughout the math package the floating point format is:
* the mantissa is 24 bits long.
* the binary point is to the left of the msb.
* the mantissa is always positive, and its msb is always 1.
* number = mantissa * 2^exponent, sign in FACSGN.
* the sign of the exponent is the msb of the exponent.
* the exponent is stored in excess $80 (i.e., it is a signed
8-bit number with $80 added to it.)
* an exponent of zero means the number is zero. (Note that
the rest of the accumulator cannot be assumed to be zero.)
* to keep the same number in the accumulator while shifting:
right shifts --> increment exponent
left shifts --> decrement exponent
Arithmetic routine calling conventions:
* For one argument functions:
the argument is in the FACC.
the result is left in the FACC.
* For two argument operations:
the first argument is in MEMORY (packed) or ARG (unpacked).
the second argument is in the FACC.
the result is left in the FACC.
* Always call ROM routines with SYSTEM memory in context (BANK $FF).
A note concerning precision. Since the mantissa is always normalized,
the high order bit of the most significant byte is always one. This
guarantees at least 40 bits (5 byte mantissa times 8 bits each) of
precision, which is approximately 9 significant digits plus a few bits
for rounding. In fact, there is a 'rounding' byte, FACOV ($71), which
should, for the greatest degree of precision, be loaded whenever you
load the FACC. The high order bit of FACOV is utilized in most of the
math routines. While some of the 'movement' routines 'round' the
loaded floating point number (i.e., FACOV = $00), others (such as
CONUPK) do not - assuming the value of FACOV is the useful result of
an operation in progress. In 99% of the cases you need not worry about
it, as its significance is virtually nil. For the greatest degree of
precision however, use it.
A few examples of normalized (FACC) floating point numbers:
VALUE EXP M A N T I S S A SIGN
------- ----- -------------------------- ----
1E38 = FF 96 76 99 53 00
4E10 = A4 95 02 F9 00 00
2E10 = A3 95 02 F9 00 00
1E10 = A4 95 02 F9 00 00
10 = 84 A0 00 00 00 00
1 = 81 80 00 00 00 00
.5 = 80 80 00 00 00 00
.25 = 7F 80 00 00 00 00
.6 = 80 99 99 99 9A 00
1E-04 = 73 D1 B7 59 59 00
1E-37 = 06 88 1C EA 15 00
1E-38 = 02 D9 C7 DC EE 00
3E-39 = 01 82 AB 1E 2A 00
0 = 00 xx xx xx xx 00
-1 = 81 80 00 00 00 FF
-5 = 83 A0 00 00 00 FF
Now for a simple example of deriving the actual binary from the FACC:
5 = 83 A0 00 00 00 00
| \
| \
($83-$80) ($A0)
|
which means: 2^3 * .10110000, or shift mantissa LEFT 3,
which gives: 101.00000 (binary) or 5.0 (hex)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: AYINT
FUNCTION: CONVERT FLOATING POINT TO INTEGER
PREPARATION: FACC contains floating point number (-32768<=n<=32767)
RESULT: FACMO ($66) contains signed integer (msb)
FACLO ($67) contains signed integer (lsb)
ERROR: ?ILLEGAL QUANTITY ERROR if FACC too big.
EXAMPLE: JSR AYINT ;INT(FACC)
LDA $66 ;MSB
LDA $67 ;LSB
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: GIVAYF
FUNCTION: CONVERT INTEGER TO FLOATING POINT
PREPARATION: .A contains signed integer (msb)
.Y contains signed integer (lsb)
RESULT: FACC contains floating point number
EXAMPLE: LDA #>INTEGER
LDY #<INTEGER
JSR GIVAYF ;FLOAT (A,Y)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FOUT
FUNCTION: CONVERT FLOATING POINT TO ASCII STRING
PREPARATION: FBUFFR ($100) contains ASCII string (null terminated)
.A contains pointer to string (lsb)
.Y contains pointer to string (msb)
EXAMPLE: JSR FOUT ;CONVERT FACC TO STRING AT $100
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: VAL_1
FUNCTION: CONVERT ASCII STRING TO FLOATING POINT
PREPAPATION: INDEX1 ($24,$25) contains pointer to string
.A contains length of string
SPECIAL NOTES: String *MUST* be in var bank. Any invalid character
terminates conversion when encountered (i.e., acts
like a terminator).
RESULT: FACC contains floating point number
EXAMPLE: LDA #<POINTER
LDY #>POINTER
STA INDEX1 ;SET POINTER TO STRING
STY INDEX1+1
LDA #LENGTH ;SET STRING LENGTH
JSR VAL_1 ;FACC = VAL(STRING)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: GETADR
FUNCTION: CONVERT FLOATING POINT TO ADDRESS
PREPARATION: FACC contains floating point number (0<=n<=65535)
RESULT: POKER ($16,$17) contains unsigned integer address
ERROR: ?ILLEGAL QUANTITY ERROR if FACC too big.
EXAMPLE: JSR GETADR ;ADR(FACC)
LDA $16 ;LSB
LDA $17 ;MSB
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FLOATC
FUNCTION: CONVERT ADDRESS TO FLOATING POINT
PREPARATION: FACHO ($64) contains address (msb)
FACMOH ($65) contains address (lsb)
.X contains exponent ($90 always)
.C=1 if positive (always)
RESULT: FACC contains floating point number
ERROR: ?OVERFLOW ERROR if FACC too big.
EXAMPLE: LDA #<ADDRESS
LDY #>ADDRESS
STA FACMOH ;SET ADDRESS
STY FACHO
LDY #$90 ;EXPONENT
SEC ;POSITIVE
JSR FLOATC ;FLOAT ADDRESS
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FSUB
FUNCTION: FACC = MEMORY - FACC
PREPARATION: FACC contains floating point subtrahend
.A = pointer (lsb) to packed floating point minuend
.Y = pointer (msb) to packed floating point minuend
SPECIAL NOTES: The minuend *MUST* be in VARBANK in packed
format. FSUB calls CONUPK to normalize it.
RESULT: FACC contains floating point difference
ERROR: ?OVERFLOW ERROR if FACC too big.
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* MINUEND
JSR FSUB ;SUBTRACT MEM FROM FACC, DIFF IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FSUBT
FUNCTION: FACC = ARG - FACC
PREPARATION: FACC contains floating point subtrahend
ARG contains floating point minuend
SPECIAL NOTES: This routine is similar to FSUB. The only difference
is the call to CONUPK. (FSUBT assumes you have
already loaded ARG with unpacked minuend.)
RESULT: FACC contains floating point difference
ERROR: ?OVERFLOW ERROR if FACC too big.
EXAMPLE: JSR FSUBT ;SUBTRACT ARG FROM FACC, DIFF IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FADD
FUNCTION: FACC = MEMORY + FACC
PREPARATION: FACC contains floating point addend
.A = pointer (lsb) to packed floating point addend
.Y = pointer (msb) to packed floating point addend
SPECIAL NOTES: The second addend *MUST* be in VARBANK in
packed format. FADD calls CONUPK to normalize it.
RESULT: FACC contains floating point sum
ERROR: ?OVERFLOW ERROR if result too big
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* ADDEND
JSR FADD ;ADD MEMORY TO FACC, SUM IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FADDT
FUNCTION: FACC = ARG + FACC
PREPARATION: FACC contains floating point addend
ARG contains floating point addend
ARISGN ($70) contains EOR(FACSGN,ARGSGN)
.A contains FACEXP
SPECIAL NOTES: This routine is similar to FADD. The only
difference is the call to CONUPK.
*********************************************
* You *MUST* put resultant sign in ARISGN. *
* You *MUST* load FACEXP ($63) immediately *
* before call so that status flags are set! *
*********************************************
RESULT: FACC contains floating point sum
ERROR: ?OVERFLOW ERROR if result too big
EXAMPLE: LDA FACSGN
EOR ARGSGN
STA ARISGN ;SET RESULTANT SIGN
LDA FACEXP ;SET STATUS FLAGS PER FACEXP
JSR FADDT ;ADD ARG TO FACC, SUM IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FMULT
FUNCTION: FACC = MEMORY * FACC
PEPARATION: FACC contains floating point multiplier
.A = pointer (lsb) to packed float. point multiplicand
.Y = pointer (msb) to packed float. point multiplicand
SPECIAL NOTES: The multiplicand *MUST* be in VARBANK in
packed format. FMULT calls CONUPK to normalize it.
RESULT: FACC contains floating point product
ERROR: ?OVERFLOW ERROR if result too big
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* MULTIPLICAND
JSR FMULT ;MULTIPLY MEM BY FACC, PRODUCT IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FMULTT
FUNCTION: FACC = ARG * FACC
PREPARATION: FACC contains floating point multiplier
ARG contains floating point muitiplicand
SPECIAL NOTES: This routine is similar to FMULT. The only difference
is the call to CONUPK. (FMULTT assumes you have
already loaded ARG with unpacked multiplicand.)
RESULT: FACC contains floating point product
ERROR: ?OVERFLOW ERROR if result too big
EXAMPLE: JSR FMULTT ;MULTIPLY ARG BY FACC, PRODUCT IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FDIV
FUNCTION: FACC = MEMORY / FACC
PREPARATION: FACC contains floating point divisor
.A = pointer (lsb) to packed floating point dividend
.Y = pointer (msb) to packed floating point dividend
SPECIAL NOTES: The dividend *MUST* be in VARBANK in packed
format. FDIV calls CONUPK to normalize it.
RESULT: FACC contains floating point quotient
ERROR: ?DIVISION BY ZERO ERROR if FACC zero
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* DIVIDEND
JSR FDIV ;DIVIDE MEM BY FACC, QUOTIENT IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FDIVT
FUNCTION: FACC = ARG / FACC
PREPARATION: FACC contains floating point divisor
ARG contains floating point divldend
ARISGN ($70) contains EOR(FACSGN,ARGSGN)
.A contains FACEXP
SPECIAL NOTES: This routine is similar to FDIV. The only difference
is the call to CONUPK. (FDIVT assumes you have
already loaded ARG with unpacked dividend.)
*********************************************
* You *MUST* put resultant sign in ARISGN. *
* You *MUST* load FACEXP ($63) immediately *
* before call so that status flags are set! *
*********************************************
RESULT: FACC contains floating point quotient
ERROR: ?DIVISION BY ZERO ERROR if FACC zero
EXAMPLE: LDA FACSGN
EOR ARGSGN
STA ARISGN ;SET RESULTANT SIGN
LDA FACEXP ;SET STATUS FLAGS PER FACEXP
JSR FDIVT ;DIVIDE ARG BY FACC, QUOTIENT IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: LOG
FUNCTION: FACC = LOG(FACC) natural logarithm (base e)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point logarithm
ERROR: ?ILLEGAL QUANTITY ERROR if FACC negative or zero
EXAMPLE: JSR LOG ;FACC = LOG(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: INT
FUNCTION: FACC = INT(FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point greatest integer
EXAMPLE: JSR INT ;FACC = INT(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: SQR
FUNCTION: FACC = SQR(FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point square root
ERROR: ?ILLEGAL QUANTITY ERROR if FACC negative
EXAMPLE: JSR SQR ;FACC = SQR(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: NEGOP
FUNCTION: FACC = -FACC (invert sign of FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point number with sign inverted
EXAMPLE: JSR NEGOP ;FACC = -FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FPWR
FUNCTION: FACC = ARG ^ MEMORY
PREPARATION: ARG contains floating point number
.A = pointer (lsb) to packed floating point power
.Y = pointer (msb) to packed floating point power
SPECIAL NOTES: The power *MUST* be in ROM or SYSTEM RAM in packed
format as FPWR calls MOVFM to unpack it into FACC.
RESULT: FACC contains floating point result
ERROR: ?ILLEGAL QUANTITY ERROR if ARG negative
?OVERFLOW ERROR if result too big
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* POWER
JSR FPWR ;COMPUTE ARG ^ MEM, RESULT IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FPWRT
FUNCTION: FACC = ARG ^ FACC
PREPARATION: ARG contains floating point number
FACC contains floating point power
.A contains FACEXP
SPECIAL NOTES: This routine is similar to FPWR. The only difference
is the call to MOVFM. (FPWRT assumes you have already
loaded FACC with unpacked power.)
*********************************************
* You *MUST* load FACEXP ($63) immediately *
* before call so that status flags are set! *
*********************************************
RESULT: FACC contains floating point result
ERROR: ?ILLEGAL QUANTITY ERROR if ARG negative
?OVERFLOW ERROR if result too big
EXAMPLE: LDA FACEXP ;SET STATUS FLAGS PER FACEXP
JSR FPWRT ;COMPUTE ARG ^ FACC, RESULT IN FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: EXP (compute e ^ FACC)
FUNCTION: FACC = EXP (FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains fIoating point result
ERROR: ?OVERFLOW ERROR if FACC too big
EXAMPLE: JSR EXP ;FACC = EXP(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: COS
FUNCTION: FACC = COS(FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point cosine (in radians)
EXAMPLE: JSR COS ;FACC = COS(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: SIN
FUNCTION: FACC = SIN(FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point sine (in radians)
EXAMPLE: JSR SIN ;FACC = SIN(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: TAN
FUNCTION: FACC = TAN(FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point tangent (in radians)
EXAMPLE: JSR TAN ;FACC = TAN(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: ATN
FUNCTION: FACC = ATN(FACC)
PREPARATION: FACC contains floating point number
RESULT: FACC contains floating point arctangent (in radians)
EXAMPLE: JSR ATN ;FACC = ATN(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: ROUND (round to 40 bits of precision)
FUNCTION: FACC = FACC + FACOV(msb)
PREPARATION: FACC contains floating point number
FACOV(msb) contains 'extra' precision
RESULT: none if FACC zero or FACOV(msb) zero
one extra bit ADDED to FACC lsb if FACOV(msb) is set
EXAMPLE: JSR ROUND ;ROUND FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: ABS (make FACSGN(msb) = $00)
FUNCTION: FACC = ABS(FACC)
PREPARATION: FACC contains (SIGNED) floating point number
RESULT: FACC contains (POSITIVE) floating point
EXAMPLE: JSR ABS ;FACC = ABS(FACC)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: SGN
FUNCTION: .A = SGN(FACC)
PREPARATION: FACC contains floating point number
RESULT: .A --> $FF if FACC negative (FACC < 0)
$00 if FACC zero (FACC = 0)
$01 if FACC positive (FACC > 0)
(status flags reflect contents of .A, carry invalid)
EXAMPLE: JSR SGN ;SGN(FACC)
; BEQ will trap =0
; BNE will trap <>0
; BMI will trap <0
; BPL will trap >=0 etc.
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: FCOMP (compare FACC with MEMORY)
FUNCTION: .A = FCOMP(FACC,MEMORY)
PREPARATION: FACC contains floating point number
.A = pointer (lsb) to packed floating point number
.Y = pointer (msb) to packed floating point number
SPECIAL NOTES: The number *MUST* be in ROM, or RAM currently in
context below ROM, in PACKED format.
*** FACOV is significant!
RESULT: .A --> SFF if FACC < MEMORY
$00 if FACC = MEMORY
$01 if FACC > MEMORY
(status flags reflect contents of .A, carry invalid)
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* NUMBER
JSR FCOMP ;COMPARE FACC WITH MEMORY
; BEQ will trap FACC = MEM
; BNE will trap FACC <> MEM
; BMI will trap FACC < MEM
; BPL will trap FACC >= MEM etc.
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: RND0
FUNCTION: FACC = random floating point number (0<n<1)
PREPARATION: .A --> $00 to generate a 'true' random number
$01 to generate next random number in sequence
$FF to start a new sequence of random numbers
based upon current contents of FACC.
SPECIAL NOTES: *MUST* be called with the system bank in context.
*MUST* load .A immediately before call so that status
flags reflect contents of .A
RESULT: FACC = floating point random number
EXAMPLE: LDA #$FF ;START REPRODUCEABLE SEQUENCE BASED ON FACC
JSR RND0
LDA #$01
JSR RND0 ;GENERATE (FIRST) RANDOM NUMBER IN SEQUENCE
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: CONUPK
FUNCTION: ARG = UNPACK(RAM_CONSTANT)
PREPARATION: .A = pointer (lsb) to packed floating point number
.Y = pointer (msb) to packed floating point number
SPECIAL NOTES: The number *MUST* be in VARBANK or SYSTEM RAM in
packed format.
RESULT: ARG loaded with normalized floating point number
ARISGN ($6F) contains EOR(FACSGN,ARGSGN)
.A contains FACEXP (status reflects contents of .A)
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* NUMBER
JSR CONUPK ;LOAD ARG
; BEQ traps ARG = $00
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: ROMUPK
FUNCTION: ARG = UNPACK(ROM_CONSTANT)
PREPARATION: .A = pointer (lsb) to packed floating point number
.Y = pointer (msb) to packed floating point number
SPECIAL NOTES: The number *MUST* be in ROM or SYSTEM RAM currently
in context (otherwise identical to CONUPK).
RESULT: ARG loaded with normalized floating point number
ARISGN ($6F) contains EOR(FACSGN,ARGSGN)
.A contains FACEXP (status reflects contents of .A)
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* NUMBER
JSR ROMUPK ;LOAD ARG
; BEQ traps ARG = $00
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: MOVFRM
FUNCTION: FACC = UNPACK(RAM_CONSTANT)
PREPARATION: .A = pointer (lsb) to packed floating point number
.Y = pointer (msb) to packed floating point number
SPECIAL NOTES: The number *MUST* be in VARBANK or SYSTEM RAM in
packed format.
RESULT: FACC loaded with normalized floating point number
FACOV ($71) cleared
EXAMPLE: LDA #<POINTER
LDY #>POINTER ;SET POINTER TO *PACKED* NUMBER
JSR MOVFRM ;LOAD FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: MOVFA
FUNCTION: FACC = ARG
PREPARATION: ARG contains floating point number
RESULT: FACC contains same number as ARG
FACOV ($71) cleared
.A contains FACEXP (but status invalid!)
EXAMPLE: JSR MOVFA ;COPY ARG TO FACC
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
NAME: MOVAF
FUNCTION: ARG = FACC
PREPARATION: FACC contains floating point number
RESULT: FACC will be ROUNDed and FACOV cleared.
ARG contains same number as FACC
.A contains FACEXP (but status invalid!)
EXAMPLE: JSR MOVAF ;COPY FACC TO ARG
3.5. C65 DOS Documentation
DIRECTORY HEADER DEFINITION
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0 TRACK mumber which points to the 1st dir. sector
1 SECTOR number which points to the 1st dir. sector
2 Disk format version number, which is currently 'D'
512 byte sectors 20 per track
20 Sectors per track
40 Tracks per side
2 sides (note they're inverted from normal MFM disk)
3 Must = 0
4 Bytes 4 thru 21 contain the volume name (label)
22 Bytes 22 and 23 contain the disk id (fake)
24 Must contain an $A0
25 DOS version number (CBMDOS = 1, 1581 = 3)
26 Format version number (currently = 'D' (fake))
27 Bytes 27 thru 28 = $A0
29 NOT USED AT THIS TIME
30 NOT USED AT THIS TIME
31 NOT USED AT THIS TIME
32 NOT USED AT THIS TIME
33 NOT USED AT THIS TIME
34 Track number which points to this directory header
35 Sector number which points to this directory header
36 Bytes 36 thru 255 are not used at this time
NOTE: If this is a subdirectory header then BYTES 32 and 33 contain
the TRACK & SECTOR number of the DIRECTORY SECTOR that points to this
DIRECTORY HEADER. See the partition command for a better description.
If this is the ROOT header then they will contain a $00.
BAM DEFINITION
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0 Track link for next bam sector, if last then end of BAMs
1 Sector link
2 Format type this disk was formatted under
3 Compliment version number of byte 2 above
4-5 Disk ID used when this disk was formatted
6 I/O byte used as follows;
BIT 7- When set Verify is performed after each disk write
BIT 6- Perform CRC check (not used by CBDOS)
BIT 1- Huge relative files disabled
7 Auto loader flag (not used by CBDOS)
8-15 Not used at this time by any CBM DOS versions
16-255 BAM image
BAM IMAGE
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0 Number of free sectors on this track
1 MSB flag for sector 7, LSB flag for sector 0
2 MSB flag for sector 15, LSB flag for sector 8
3 MSB flag for sector 23, LSB flag for sector 16
4 MSB flag for sector 31, LSB flag for sector 24
5 MSB flag for sector 39, LSB flag for sector 32
DIRECTORY SECTOR DEFINITION
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0 TRACK -- Points to the next directory track.
1 SECTOR -- Points to the next directory sector.
(IF TRACK = 0 THEN THIS IS THE LAST DIRECTORY SECTOR)
FILE ENTRY DESCRIPTION
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0 File status byte which is used as follows:
BIT 7- Set indicates properly closed file
BIT 6- File is locked (read only)
BIT 5- Save with replace is CURRENTLY in effect,
when file is closed this bit is deleted.
BIT 4- NOT USED AT THIS TIME
BIT 3- Bits 3 thru 0 are used to indicate the filetype:
0=DEL, 1=SEQ, 2=PRG, 3=USER, 4=REL, 5=CBM, 6=not used
7=used by dos to represent DIRECT type of file access
1 TRACK - link to the 1st sector of data for this file.
2 SECTOR - link to the 1st sector of data for this file.
3 Bytes 3-18 contain the filename in ASCII, padded with $A0
19 Side Sector TRACK link for relative files
GEOS - Track number of GEOS file header
20 Side Sector SECTOR link for relative files
GEOS - Sector number of GEOS file header
21 Record size for relative files
GEOS - File structure type 0=SEQ, 1=VLIR
22 GEOS - FILE TYPES:
13 = Swap file 12 = System boot 11 = Disk device
10 = Input device 09 = Printer 08 = Font
07 = Appl. data 06 = Applications 05 = Desk Acc.
04 = System 03 = Basic data 02 = Assembly
00 = Not GEOS
23 Not used by CBM DOS previous to CBDOS
GEOS - DATE: Year last modified (offset from 1990)
CBDOS- Bits 7-4 contain the upper 4 bit's from the
file type byte (see byte 0 above) for the
UNNEW, UNSRATCH commands used by CBDOS
24 Not used by CBM DOS previous to CBDOS
GEOS - DATE: Month last modified (1 thru 12)
CBDOS- Bit's 7 thru 4 contain the lower 4 bit's from the
file type byte (see byte 23 above)
25 GEOS - DATE: Day last modified (1 thru 31)
26 TRACK (from 1) for the save with replace file
GEOS - DATE: Hour last modified (0 thru 23)
27 SECTOR (from 2) for the save with replace file
GEOS - DATE: Minute last modified (0 thru 59)
28 LSB of the # of sectors used by this file
29 MSB of the # of sectors used by this file
NOTE: Each sector in the directory contains 8 entries of 32 bytes each.
SIDE SECTOR FORMAT DEFINITION
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0 Next Side Sector TRACK link ($FF if last)
1 Next Side Sector SECTOR link
2 Side Sector number
If this is a SUPER SIDE SECTOR then this contains an $FE
(see the description of the SUPER SIDE SECTOR below)
3 Record Size
4-5 TRACK & SECTOR link of Side Sector number 0
6-7 TRACK & SECTOR link of Side Sector number 1
8-9 TRACK & SECTOR link of Side Sector number 2
10-11 TRACK & SECTOR link of Side Sector number 3
12-13 TRACK & SECTOR link of Side Sector number 4
14-15 TRACK & SECTOR link of Side Sector number 5
16-17 TRACK & SECTOR link of the DATA BLOCK #0
18-19 TRACK & SECTOR link of the DATA BLOCK #l
etc...
NOTE: There are 91 groups to the largest file that this DOS can handle.
SUPER SIDE SECTOR FORMAT DEFINITION
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0 Next Side Sector TRACK link (SFF if last)
1 Next Side Sector SECTOR
2 Contains an SFE to indicate this is a SUPER SIDED SECTOR
3-4 TRACK & SECTOR link of Side Sector number 0
5-6 TRACK & SECTOR link of Side Sector number 1
7-8 TRACK & SECTOR link of Side Sector number 2
9-10 TRACK & SECTOR link of Side Sector number 3
11-12 TRACK & SECTOR link of Side Sector number 4
13-14 TRACK & SECTOR link of Side Sector number 5
..... ...........................................
253-254 TRACK & SECTOR link of Side Sector number 125
NOTE:There are 91 groups to the largest file that this DOS can handle.
DATA SECTOR DEFINITION
----------------------------------------------------------------------
BYTE DESCRIPTION
------ --------------------------------------------------------------
0-1 TRACK and SECTOR link to the next data block. If track=0
then sector contains the number of bytes used in this
sector (which will always be at least 2 on the last block
for the T&S link bytes).
NOTE: Used by DEL, SEQ, PRG, REL (data blocks) and USR.
;*-------------------------------------------------------------------*
;* Format a track *
;* 10 sectors per track numbered 1-10, 512 byte sectors *
;*-------------------------------------------------------------------*
;* 12 Sync marks 00 *
;* 3 Header ID marks w/missing clock A1 *
;* 1 Header ID FE *
;* 4 Header bytes Track *
;* Side *
;* Sector *
;* Sector size *
;* 2 Header CRC bytes xx,xx *
;* 22 Data gap bytes 4E *
;* 12 Sync marks 00 *
;* 3 Data block ID marks w/missing clock A1 *
;* 1 Data block ID FB *
;* 512 Data block fill bytes 00 *
;* 2 Data block CRC bytes xx,xx *
;* 24 Sector gap bytes 4E *
;*-------------------------------------------------------------------*
;*-------------------------------------------------------------------*
;* Calculate the 2 bytes CRC for each sector header of an entire *
;* track of 10 sectors. AXYZ are trashed. *
;* *
;* This routine is based on the Cyclical Redundancy Check *
;* on the polynomial: A^16+A^12+A^5+1. *
;* *
;* HEADER contains TRACK,SIDE,SECTOR,2 [sector size] *
;* *
;* DO WHILE ne = 0 *
;* DO FOR each bit in the data byte (.a) [from lsb to msb] *
;* IF (LSB of crc) eor (LSB or data) *
;* THEN CRC = (CRC/2) EOR polynomial *
;* ELSE CRC = (CRC/2) *
;* END IF *
;* LOOP *
;* LOOP *
;*-------------------------------------------------------------------*
;*-------------------------------------------------------------------*
;* SIDE = (LogicalSector >= 20) AND 1 *
;* TRACK = LogicalTrack - 1 *
;* StartingSector = SIDE * 20 *
;* SECTOR = (LogicalSector - StartingSector) / 2 + 1 *
;* HALF = (LogicalSector - StartingSector) AND 1 *
;*-------------------------------------------------------------------*
C65 Partition and Subdirectory Syntax
This specification describes a _proposed_ C65 partition/subdirectory
parser.
OPEN la,fa,sa, "[#]/path/:filename"
OPEN la,fa,15, "<cmd>#/path/:[cmd_string]"
where: # is an optional "drive" number, 0-3.
/path/ is a partition or subdirectory name
: delimits the path from the filename
and: <cmd> is a DOS command (such as I,N,S,C, etc.)
(cmd_string) is an optional string required by some commands.
The first example illustrates a typical filename specification, the
second example illustrates a command channel instruction.
OPEN la,fa,sa, "0/SUBDIR1/SUBDIR2/:FILE,S,W"
Action taken Why
------------------------------------ -------------------------------
1. Select the "root" 0
2. Find & enter two subdirectories /SUBDIR1/SUBDIR2/:
(the trailing "/" is required
to be compatible with CMD?)
3. Create & open file for writing FILE,S,W
The "root" or "drive number", path, and ":" are all optional. If they
are omitted, the file is opened in the current partition. Some
similar, and legal, syntaxes are:
OPEN la,fa,sa, "FILE,S,W" (create "FILE" in current part)
OPEN la,fa,sa, ":FILE,S,W" (create "FILE" in current part)
OPEN la,fa,sa, "0:FILE,S,W" (create "FILE" in current part)
OPEN la,fa,sa, "/SUBDIR/ FILE,S,W" (from current partition, enter
"SUBDIR" and create "FILE")
OPEN la,fa,sa, "//SUBDIR/:FILE,S,W" (from Root partition, enter
"SUBDIR" and create "FILE")
OPEN la,fa,sa, "@0/SUBDIR/:FILE" (open "FILE" in "SUBDIR" for
writing)
Some questionable syntaxes, and their affect, are:
OPEN la,fa,sa, "0FILE,S,W" (this would create file "0FILE")
OPEN la,fa,sa, "/SUBDIR/FILE,S,W" (creates file "/SUBDIR/FILE"
OPEN la,fa,sa, "@0:FILE,S,W" (open filr "FILE" in current
partition for writing)
OPEN la,fa,sa, "/0:FILE,S,W" (? should create file "0:file",
note this is not the cmd chnl)
Some legal commands:
OPEN la,fa,sa,"I0" (initialize current partition)
OPEN la,fa,sa,"I//" (initialize Root)
OPEN la,fa,sa,"I0/SUBDIR/:" (enter "SUBDIR" and initialize)
OPEN la,fa,sa,"N0/SUBDIR/:NAME,ID" (enter "SUBDIR" and "new" it)
OPEN la,fa,sa,"S0/SUBDIR/:FILE" (delete "FILE" in "SUBDIR")
OPEN la,fa,sa,"/0:SUBDIR" (1581 partition select, "/" in
this context is a command
itself)
Some proposed general rules, designed to be compatible with both the
1581 subpartitioning syntax and CMD syntax:
1. The name of a subdirectory must always be separated from the
filename by a colon (":").
2. Each subdirectory name must be delimited by a slash ("/").
3. To select Root directory (partiton), specify two slashes ("//").
This allows older applications specifying the drive number ("0:")
to be run in a partition.
CURRENT PARTITION ROUTINES
Create Partition:
"/0:PAR_NAME,"+(START-TRK)+(START-SECTOR)+(LO-BLKS)+(HI-BLKS)
Select Partition:
"/0:PAR_NAME" will select given filname as subdirectory
"/0" will select root directory
SELECT PARTITION
This routine will allow the user to quickly select partition paths
using the normal SA values other than 15. To use this new method the
user opens the file using a normal SA and the filename MUST be
structured as follows:
"/<drive>:PATH_1/PATH_2/PATH_3..... ETC"
If the dos does not find one of the filenames in the file path stream
it will check to see if the file exists in the current directory and
if it does it will open the file in the normal method as it does now.
;*********************************************************************
;* FILE_COMMANDS *
;* *
;* The following set of command channel routines were added to allow *
;* the user a graceful way of manipulating files: *
;* *
;* "F-L" Locate a file to prevent it from being scratched *
;* "F-U" Unlock a file and allow it to be scratched *
;* "F-R" Restore a file after it has been scratched *
;* *
;* Following each command above is the drive number, followed by a *
;* colon then followed by the filename(s). For example, to lock all *
;* the files on drive 0 you would send the following file command: *
;* *
;* OPENXX,XX,15,"F-L0:*" *
;* *
;* OPENXX,XX,15,"F-L0:FNAME,FNAME1,FNAME2,... ETC" *
;*********************************************************************
;*********************************************************************
;* BLOCK STATUS *
;* *
;* Syntax: "B-S:CHANNEL NUMBER, DRIVE NUMBER, TRACK, SECTOR" *
;* *
;* Then check error channel for normal errors then get one byte from *
;* from the channel number. If it is a 0 then the sector is free. *
;* 1 indicates the sector is in use. *
;* *
;* This command was added to enable an easy method of finding out if *
;* a given track or sector is currently marked as being used in a *
;* drive's BAM or not. *
;* *
;* CBDOS CHGUTIL *
;* *
;* COMMAND COMMENTS DRIVES USED ON *
;* "U0>B"+chr$(n) b = set fast/slow serial bus 1581 *
;* "U0>D"+chr$(n) d = set dirsecinc CBDOS *
;* "UO>H"+chr$(n) h = set head selection 0,1 1571 *
;* "U0>M"+chr$(n) m = set dos mode 1571 *
;* "U0>R"+chr$(n) r = set dos retries on errors 1571,1581 *
;* "UO>S"+chr$(n) s = set secinc 1571,1581,CBDOS *
;* "U0>V"+chr$(n) v = set verify on/off 1581,CBDOS *
;* "U0>?"+chr$(n) ? = set device number CBDOS *
;* "U0>L"+chr$(n) = set large rel files on/off CBDOS *
;* "U0>MR"+ xx = perform memory read 1581 *
;* "U0>MW"+ xx = perform memory write 1581 *
;* 12345 *
;* ^--------------- CMDSIZ points to end of starting string @1 *
;*********************************************************************
FLOPPY DISK CONTROLLER ERRORS
IP FDC DESCRIPTION
-- --- -----------
0 (0) no error
20 (2) can't find block header
23 (5) checksum error in data
25 (7) write-verify error
26 (8) write w/ write protect on
27 (9) crc error in header
Information description
-----------------------
1 files scratched
2 selected partition
3 files locked
4 files unlocked
5 files restored
Parameter errors
----------------
30 general syntax
31 invalid command
32 long line
33 invalid filname
34 no filenames given
Relative file errors
--------------------
50 record not present
51 overflow in record
52 file too large
53 big relative files disabled
Open routine errors
-------------------
60 file open for write
61 file not open
62 file not found
63 file exists
64 file type mismatch
Sector management errors
------------------------
65 no block
66 illegal track or sector
67 illegal system t or s
General channel/block errors
----------------------------
02 channel selected
70 no channels available
71 bam corrupted error
72 disk full
73 cbdos v1.0
74 drive not ready
75 format error
76 controller error
77 selected partition illegal
78 directory full
79 file corrupted
3.6. C64DX RS-232 DRIVER
00A7 rs232_status - UART status byte
00A8 rs232_flags - open flag, xon/xoff status
- b7: channel open (reset)
- b6: flow control (1=x-line)
- b5: duplex (1=half)
- b1: XOFF received
- b0: XOFF sent
00A9 rs232_jam - system character to xmit
00AA rs232_xon_char - XON character (null=disabled)
00AB rs232_xoff_char - XOFF character (null=disabled)
00B0 rs232_xmit_empty - xmit buffer empty flag (0=empty)
00B1 rs232_rcvr_buffer_lo - lowest page of input buffer
00B2 rs232_rcvr_buffer_hi - highest page of input buffer
00B3 rs232_xmit_buffer_lo - lowest page of output buffer
00B4 rs232_xmit_buffer_hi - highest page of output buffer
00B5 rs232_high_water - point at which receiver XOFFs
00B6 rs232_low_water - point at which receiver XONs
00C4 rs232_rcvr_head - pointer to end of buffer
00C6 rs232_rcvr_tail - pointer to start of buffer
00C8 rs232_xmit_head - pointer to end of buffer
00CA rs232_xmit_tail - pointer to start of buffer
RS-232 interrupt-driven handler
How it works: when an RS232 channel is OPENed, buffers are flushed,
all flags and states are reset, and the receiver IRQ is enabled. When
a byte is put into the xmit buffer by BSOUT, the xmit IRQ is enabled.
The xmit IRQ is disabled whenever the xmit buffer is found to be empty
or an XOFF is received (it is enabled whenever an XON is received).
CLOSE will hang until the xmit buffer is empty, and BSOUT will hang
when the xmit buffer is full. IRQs must be allowed by the user at all
times (and especially during BSOUT calls) for proper operation. (The
RS232 channel will work even if IRQs are disabled by the user, but
thoughput will be reduced to the frame rate (normal system raster IRQ)
and the system can hang forever should the xmit buffer become full and
BSOUT is called with a byte to xmit). A successful CLOSE will disable
all RS232 interrupts and re-init everything.
Note that DOS calls disable both IRQ and NMI interrupts while the DOS
code is in context. The remote should be XOFFed to avoid loss of data.
Refer to the UART specification for register description & baud rate
tables.
Open an RS-232 channel
This is different from the usual C64/C128 command string.
1 2 3 4 5 6
Command string bytes: baud|word|parity|stop(unused)|duplex|xline
4.0. C65 DMAgic (F018B) DMA Coprocessor
Also refer to chapter 2.7., this chapter has originally been a
separate document.
4.1. Introduction
The C64DX DMAgic chip is a command-list DMA (Direct Memory Access)
coprocessor with integrated blitter capabilities. It is used to copy
or fill linear or rectangular areas of memory much faster than is
possible using the CPU. DMAgic can perform logical operations and
shifts of binary data, and it is particularly well suited to graphics
operations. It has absolute address access to the entire one megabyte
address space of the C65, and translated address access to VIC
graphics memory using simple X-Y coordinates.
A DMA/blitter coprocessor can be used for many different types of
operations in a computer system such as the C65, and DMAgic is very
versatile in this regard. Although each of these uses may require
significantly different command specifications, DMAgic is very easy
to program and use.
Throughout this chapter the term "DMAT" will refer to any DMAgic
Transfer operation. A DMAT is prepared by creating a 12-byte DMAT
instruction list anywhere in the RAM. A DMAT is executed
automatically after writing the address of the DMAT instruction list
to DMAgic's LP/trigger (List Pointer) register.
A DMAT list can be prepared in advance and executed at any time by
pointing the DMAgic chip to it. Optionally, DMAT lists can be
chained together and the collection of lists executed with a single
trigger. Additionally, DMATs can be interruptable/continuable to
yield to processor or system interrupts.
In general, a DMAT instruction list consists of a Command specifying
the type of operation to be performed, a Count of the number of
memory bytes to be transferred, and the Source and Destination
addresses of the data to be transferred. When the address of the
instruction list is written to the LP/trigger register, DMAgic
temporarily takes control of the system from the CPU, automatically
loads its internal registers from the instruction list, and proceeds
to execute the specified DMAT operation. The completion status of
the operation can be read from DMAgic's status register, and
(optionally) interrupted operations can be resumed or canceled.
4.2. DMAT External Registers
Externally, DMAgic appears as four registers located in I/O space at
$D700. There are three write-only address registers and one R/W
status register. The order in which the address/trigger registers
are written is very important, so as to avoid inadvertantly
triggering a DMA operation with an invalid list pointer. The usual
procedure is:
1. Write the number of the list's bank (0-15) to LP_BNK.
2. Write the high byte of the list's address to LP_HI.
3. Write the low byte of the list's address to LP_LO/TRIGGER.
As soon as the LP_LO/TRIGGER register is written to, the CPU is
suspended and the DMA operation commences. When the DMA operation is
complete, the CPU resumes processing with the very next instruction
following the write cycle. The contents of the instruction list, and
the DMAgic LP registers, are unchanged. The very same DMA operation
could be performed again by performing step 3 above only.
In the case where a DMAT is made interruptable and an interrupt (IRQ
or NMI) were to occur, DMAgic would enter a "spin" state, and release
the bus to the CPU. Upon completion of its interrupt service
routine, the CPU would signal DMAgic that it can resume the DMAT by
reading the STATUS register, or cancel the unfinished DMAT by writing
to the STATUS register (writing to the TRIGGER register would
effectively cancel the pending DMAT and start a new one). The
following code illustrates a generic DMAT call for a previously
prepared DMAT instruction list:
LDA #bank ;The bank (0-15) where the list is
STA $D702
LDA #>address ;The high byte of the list address
STA $D701
LDA #<address
STA $D700 ;The low byte of the list address
;This also triggers the DMA operation,
;and the CPU is suspended
loop: BIT $D703 ;Check status (in case IRQ/NMI enabled)
BMI loop ; busy
4.3. DMAT Internal Registers
A DMAT operation is specified by a twelve-byte command spec called a
DMAT list. Upon writing to the LP_LO/TRIGGER register ($D700), the
coprocessor will fetch the DMAT list and initialize its internal
registers according to the contents of the list. The DMAT list
consists of a primary COMMAND byte, two COUNT bytes, three SOURCE
Address bytes, three DESTINATION Address bytes, a secondary COMMAND
byte, and two MODULO/MODE bytes, as shown in the register description.
The entire list must be completely specified; unused (unrequired)
parameters must be set to zero. Many of the internal registers have
different functions, dependent upon the command mode(s) selected.
DMAgic OPERATING MODES
The primary command byte CMD_LO specifies what kind of DMAT operation
is to be performed:
* COPY - Copy a block of memory to another area in memory.
* MIX - Perform a boolean minterm mix of a source block of memory
with a destination block of memory.
* SWAP - Exchange the contents of two blocks of memory.
* FILL - Fill a block of memory with a source byte.
Also located in the CMD_LO byte are various control parameters for
the command. An S_DIR and D_DIR bit provide independant direction
control for both the source and destination address pointers.
Transfers may be ascending (UP), or descending (DOWN), or mixed. The
TEST bit can be set to tell DMAgic to test the memory blocks without
WRITING a result, and to quit early if a collision or verify error is
detected. If the CHAIN bit is set, DMAgic will fetch and execute the
next twelve-byte DMAT list in memory upon completion of this DMAT.
If the INT bit is set, DMAgic will suspend this transfer if either an
IRQ or NMI system interrupt occurs. The operation will be continued
following a READ of the STATUS register ($D703).
The secondary command byte CMD_HI specifies the addressing mode
DMAgic is to use during the DMAT operation. There are four
addressing modes: LINEAR MODE, MODULO MODE, HOLD MODE, and XY_MOD
MODE. The lower nybble (4 bits) of CMD_HI specifies which addressing
mode is to be used for the Source and Destination Address pointers.
THIS DETERMINES THE FORMAT IN WHICH THE COUNT, SOURCE AND DESTINATION
ADDRESS, AND MODULO BYTES MUST BE GIVEN. For LINEAR and HOLD modes,
ABSOLUTE addresses, a 16 bit count, and a ZERO modulo are required.
For MODULO mode, ABSOLUTE addresses, an 8-bit rows-count, an 8 bit
columns-count, and a 16 bit modulo are required. Finally, if XY_MOD
mode is selected, RELATIVE X-Y coordinate addresses, an 8 bit
rows-count, an 8 bit columns-count, an 8 bit modulo, and an 8 bit
XY_MISC must be given.
ADDRESSING MODES: HOLD MOD ADDRESSING MODE
------------------------------------------------------------
0 0 LINEAR - CONSECUTIVE
0 1 MODULO - RECTANGULAR
1 0 HOLD - CONSTANT
1 1 XY_MOD - BITMAP RECTANGULAR
There is one more bit in the Source and Destination Address Bank
bytes, called I/O, that tells DMAgic whether to access system memory,
or memory mapped I/O space. This could be used in conjuntion with
the HOLD bit to tranfer to or from an I/O port, such as an expansion
cartridge, hard disk controller, or network interface.
4.4. Memory Layout
Most routine data transfer operations can be performed with a linear
DMAT, where all addresses are consecutive. The transfer length in
this case is specified as a 16 bit count (CNT_LO,CNT_HI), up to a
maximum of 64K bytes long (a value of zero is used to tranfer a full
64K bytes). With the use of the MODULO register, rectangular blocks
of data, such as characters on a text screen, or graphic images on a
bitmap screen, can be moved as a windowed operation, without
disturbing adjacent data. In this mode, the length of transfer is
specified by COLUMNS and ROWS, with a maximum of 256 columns(bytes)
by 256 rows(lines).
Bitplane display memory in the C65 is organized as 8 x 8 bit grouped
cells as described in the graphics chapter. Due to this arrangement,
a normal "linear" transfer would not produce the desired results.
Instead, a special XY_MODE has been included to perform the necessary
address-munging on the fly. In this mode, only the X and Y
coordinates of the start of the block, as well as the screen location,
must be specified, and DMAgic will compute the translated display
address.
DMAgic performs all transfers on byte boundaries, and as such, is not
a bit blitter. However, through careful programming, the coprocessor
can perform many "bit" type operations. Using the built-in logic
operations and bit-barrel-shifter, individual bits (or pixels) may
be manipulated, making DMAgic particularly well suited to bitplane
graphics operations.
4.5. Using DMAgic from BASIC
BASIC 10.0 provides a DMA command to make it easy to access the
capabilities of the DMAgic chip. The parameters of the DMA command
are used to construct and execute a DMAT list. All of the DMAGIC
capabilities are available through this command except for list
chaining. Refer to the BASIC Encyclopedia in Chapter 8 for details.
Note that the BASIC DMA command allows you to specify the count and
address parameters as single, 16-bit values, and automatically
defaults optional parameters to zero.
Alternatively, you can program your own machine language routine to
execute DMAT lists which have been POKEd or BLOADed into memory. You
cannot use the BASIC POKE command to execute a DMAT list because
BASIC itself uses DMA to parse and execute BASIC commands such as
POKE. While not as convenient as BASIC's DMA command, user
programmed DMA operations can be much faster, and allow use of
special DMAGIC features such as chaining.
4.5.1. Linear Examples
The most common use of DMA is to copy or fill consecutive memory
locations using the default LINEAR addressing mode. When operating
in Linear mode, the DMA chip will increment or decrement the Source
and Destination addresses for Count number of bytes.
The following example copies 80 characters from the first line of the
text screen ($00800) to the second line ($00850), and the associated
attributes (starting at $1F800):
10 REM CMD, CNT, SRC_ADR & BANK, DEST_ADR & BANK COPY:
20 DMA 0, 80, DEC("0800"), 0, DEC("0850"), 0 :REM CHARACTERS
30 DMA 0, 80, DEC("F800"), 1, DEC("F850"), 1 :REM COLORS
The following example fills the first line of the text screen with
'*' characters:
10 REM CMD, CNT, FILL_BYTE, (unused), DEST_ADR & BANK FILL:
20 DMA 3, 80, ASC("*"), 0, DEC("0800"), 0
Note that only 6 parameters were required for these two simple
transfers. The Secondary command and Modulo bytes can be omitted for
a LINEAR DMAT, and the BASIC interpreter will automatically set them
to zero.
4.5.2. Modulo Example
Windowing systems have become popular on computers. A window is
frequently used to temporarily display a message or offer a menu of
options, and then "go away" without disturbing previous information
on the screen. To accomplish this, a program must save the area
where a window is to appear, display the window, and then restore the
saved area when the window is "closed".
DMAgic has an addressing mode which supports windowing operations,
called MODULUS mode, where an area so many columns wide by so many
rows high is copied or filled. After each byte in a particular row
is accessed, the address pointers are incremented by one. At the end
of each row, a 16 bit MODULO or SKIP value is added to the address
pointers to advance them to the first location in the next row.
In the next example, let's display a 10 column by 6 row "window" near
the center of a text screen. The text screen starts at $00800, and
we'll use some free memory at $01900 as a save buffer. Where the
upper left corner of the window appears will be the Source address,
and it's calculated as:
ScreenAddress + StartColumn + (StartRow*ScreenWidth).
The Destination address is simply the address of our save buffer. The
Count for a MODULO operation requires us to combine the dimensions of
the window into a single 16-bit value: #Rows*256 + #Columns. The
MODULO (SKIP) value, MOD_LO and MOD_HI, is calculated as:
ScreenWidth - #Columns +1.
The CMD_LO byte will specify a copy operation, and the CMD_HI byte
will specify the Source addressing mode to be Modulo (01) and the
Destination addressing mode to be Linear (00):
10 LIST :REM DISPLAY SOMETHING
20 SZ = RWINDOW(2) :REM DETERMINE SCREEN SIZE
30 ADR = DEC("0800")+12+13*SZ :REM WINDOW ORIGIN AT 12,13
40 CNT = 10+6*256 :REM WINDOW SIZE 10X6
50 BUF = DEC("1900") :REM 256 CHARACTER BUFFER
60 SKP = SZ-10+1 :REM SKIP VALUE FOR 10 COLS
100 :REM SAVE & CLEAR WINDOW AREA
110 REM CMD, CNT, SRC_ADR, DEST_ADR, CMD_H, MOD_L, MOD_H
120 DMA 0, CNT, ADR, 0, BUF, 0, DEC("01"), (SKP AND255), SKP/256
130 DMA 3, CNT, ASC(" "),0, ADR, 0, DEC("04"), (SKP AND255), SKP/256
140 RCURSOR X,Y: WINDOW 12,13, 12+10-1,13+6-1 :REM SAVE CURSOR POSITION
150 FOR I = 0 TO 99: PRINT "WINDOWS! ";: NEXT :REM DISPLAY DATA IN WINDOW
200 :REM RESTORE PREVIOUS DATA
210 REM CMD, CNT, SRC_ADR, DEST_ADR, CMD_H, MOD_L, MOD_H
220 DMA 0, cnt, buf, 0, adr, 0, DEC("04"), (skp AND255), skp/256
230 PRINT CHR$(19);CHR$(19) :REM CLOSE WINDOW
240 CURSOR X,Y :REM RESTORE CURSOR
Notice that the MODULO addressing mode was used whenever we accessed
the screen, and the LINEAR addressing mode was used whenever we
accessed the save buffer. This demonstrates DMAgic's ability to mix
addressing modes independently for Source and Destination addresses.
An important point to understand is that when a MODULO mode is chosen
for either Source or Destination, the DMA counter becomes column-by-
row based, and this dictates how many bytes will be transferred.
4.5.3. XY_Mod Example
The MODULO mode described above works well on text screens, but
bitplane graphic memory on the C65 is not organized in a "raster" or
consecutive fashion. Instead, graphic memory consists of stacks of
8 bytes called cells. To accomodate this arrangement, DMAgic supports
an XY_MOD mode to allow you to address blocks or windows in the
bitplane simply by specifying their X-Y coordinates. DMAgic then
performs the necessary address translation, and knows to add an
adjusted XY_MODULO at the end of each row.
There are a few differences to keep in mind when using XY_MOD mode:
1. Like MODULO mode, Count is specified as column-by-row, but on a
bitplane screen, a column is 8 pixels on the X axis, while a row
is 1 pixel on the Y axis. (A character on the text screen is 8x8
pixels.) This allows for virtual sprites as wide as the screen,
and up to 256 pixels high.
2. SA22-SA16 and DA22-DA16 are still specified normally in all modes,
but SA15-SA13 and DA15-DA13 are shared as SD15-SD13 and appear in
the XY_MISC byte as XY_SCREEN_LOC. Note that bitplanes must start
on even 8K (320 mode) or 16K (640 mode) boundaries within a bank.
3. You must specify in the XY_MISC byte whether the bitplane is 640
or 320 wide, and 400 or 200 high.
4. XY_MOD mode only allows a 1-byte MODULO, MOD_L, which is adequate
for low and high resolution, normal and interlaced graphic
screens. XY_MODULO = 128-Box_Width+1.
5. SA12-SA0 and DA12-DA0 are replaced by 7-bit X specifiers and 9-bit
Y specifiers in the Source and Destination Pointers. This allows
access to 128 bytes (or 1024 pixels) on the X axis, and 512 pixels
on the Y axis. This more than accomodates bitplane screen modes
up to 640x400.
6. Since tranfers are done on byte boundaries in the X direction, a
barrel shifter is provided to manipulate pixels within a byte.
This is specified by the 3-bit XY_SHIFT_OFFSET in the XY_MISC
byte. (Note that the barrel shifter is available only when XY_MOD
mode is selected.)
A very useful application of DMAgic is to slide a graphic image
across the screen. The VIC supports 8 hardware sprites, but they are
somewhat limited in size and color depth. "Virtual" sprites
implemented via DMAgic can move images as large as the entire screen,
and up to 8 bitplanes can be "blitted" giving virtual sprites up to
256 colors.
Below is an example utilizing a XY_MOD bitplane DMAT. A one-bitplane
graphics screen is opened and initialize it as described in the
Graphics Chapter:
10 TRAP 900: BANK 128: GRAPHIC CLR :REM INIT GRAPHICS
20 SREEN DEF 1,0,0,1 :REM OPEN 320X200X1 SCREEN
30 SCREEN OPEN 1
40 PALETTE 1,0, 0,0,0 :REM DEFINE PALETTE BLACK
50 PALETTE 1,1, 15,15,15 :REM WHITE
60 SCREEN SET 1,1 :REM ACTIVATE IT
70 SCREEN CLR 0: BORDER 0
First we will draw a box 18 lines high and 7 bytes (56 pixels) wide.
We will locate it on line 60, column 2. We'll be using the FILL, and
later the CoPY, commands. To make our DMA commands more readable, we
will use meaningful variable names:
100 DO :REM DRAW ON A BITMAP SCREEN
110 HGT = 24: WID = 7: ROW = 60: COL = 2: CPY = 0: FILL = 3
120 CNT = HGT*256 + WID: DEST = ROW*128 + COL
130 CMHI = 8 + 4 :REM DEST USES XYMOD ADDRESSING
140 XYMD = 128 - WID + 1 :REM STANDARD FORMULA FOR XYMOD
150 SCRLOC = PEEK(DEC("D033")+2)AND14 :REM FIND BITPLANE LOCATION
160 MISC = SCRLOC * 8 :REM SHIFT SCRLOC TO BIT(6:4) OF XYMISC
170 DMA FILL,CNT,DEC("AA"),0,DEST,0,CMHI,XYMD,MISC :REM FILL A BOX
180 PEN 0,1: CHAR 3,68,1,1,2,CHR$(2)+"C65!!" :REM PUT TEXT IN IT
Line 120 shows the standard formulas to use in XYMOD mode for the
CouNT, as well as the SouRCe and DESTination address pointers. The
reason that ROW is multiplied by 128 is that the Y (or ROW) value
occupies the upper 9 bits, while the X (or COL) value is the lower 7
bits of the address pointer value.
Line 130 sets our CoMmand_HI byte to 12, which tells DMAgic that that
the DESTination pointer is using XYMOD mode addressing. Line 140
shows the standard formula for XYMoDulus (MOD_LO), when in XYMOD mode.
Line 150 finds the SCReen LOCation value that is required in the
XYMISC byte. We are PEEKing the VIC bitplane pointer register to see
where the VIC is pointing. In line 160, we shift this value (* 8) to
B6:B4 of xyMISC.
Line 170 performs a FILL on the box with the FILL_BYTE of $AA, or
"10101010". Then in line 180, we use a BASIC graphic command to
print "C65!!" in it.
190 CMDHI = 8 + 4 + 2 + 1 :REM DEST AND SRC USE XYMOD
200 FOR COL = 10 TO 26 STEP 8 :REM STEP BY 8 BYTES
210 SRC = DEST: DEST = ROW*128 + COL :REM SRC = PREVIOUS DEST
220 DL = 5: GOSUB 800 :REM DELAY
230 DMA CPY,CNT,SRC,0,DEST,0,CMHI,XYMD,MISC :REM COPY THE BOX
240 NEXT COL :REM STAMPS BOX ACROSS SCREEN
500 LOOP :REM FOREVER
800 TI$="": DO:LOOP UNTIL TI>DL: RETURN :REM DELAY SUBROUTINE
900 :REM ERROR TRAPPING...
910 SCREEN CLOSE 1: PALETTE RESTORE: BORDER 6 :REM RESTORE TEXT SCREEN
920 END
Lines 190 to 240 perform a loop that copies the image to a
DESTtination 8 bytes to the right of the SRC image. The image is
copied 3 more times. You might want to clean up the image's "trail"
to make it look like it's sliding. Just add this line to fill it
with zeros:
235 DMA FILL,CNT,0,0,SRC,0,CMHI,XYMD,MISC :REM ERASE OLD BOX
4.5.4. Barrel Shifter Example
Below is an example which smoothly shifts an image across the screen
using the BARREL SHIFTER and DESCENDING mode. Normal ASCENDING mode
would be used to SHIFT to the right on the bitmap screen. Since
we've already moved it to the right side, we'll slide it to the left,
back to its original starting location. We will accomplish this by
choosing a box that is the full width of the screen (40 bytes), and
the height of our image (24 rows). We will tell DMAgic to shift this
entire box left by one pixel. Using a FOR-NEXT loop, we'll repeat
this 191 times (26*8 -(2*8+1)), or until the image is back at column
2. This represents 8 pixel-shifts per column, by 24 total columns-1.
Add the following code to the program:
300 : :REM SLIDE USING BARREL SHIFTER
310 SHFT = 1: MISC = SCRLOC * 8 + SHFT :REM SHFT IS BIT(2:0) OF XYMISC
320 COL = 0: WID = 40: CNT = HGT*256 + WID :REM BOX IS FULL SCREEN WIDTH
330 SRC = (ROW + HGT -1)*128 + (COL + WID -1):REM SRC IS LOWER RIGHT CORNER
340 CMHI = 8 + 4 + 2 + 1: XYMOD = 128 - WID + 1
345 : :REM IMAGE STARTS IN COLUMN 26
350 FOR SLIDE = 26*8 TO 2*8+1 STEP -1
360 DMA CPY+32+16,CNT,SRC,0,SRC,0, CMHI,XYMD,MISC :REM COPY IN PLACE
370 NEXT SLIDE :REM SLIDES BOX
In line 310, we are setting the SHIFT value to 1, and ORing it into
B2:B0 of the XYMISC byte. A shift can be from 1 to 7 pixels, either
to the LEFT or the RIGHT as determined by DESCENDING or ASCENDING
mode respectively. Since we want to shift left, we selected
DESCENDING mode.
In line 320, we are saying that the box is 40 bytes wide and that it
starts in column 0. This is actually wider than we need, but we're
making it the full screen width to save ourselves a few calculations.
Notice in line 330 that we are calculating the SRC address according
to the LOWER-RIGHT corner of the box, instead of the upper-left.
This is the first requirement for DESCENDING mode. We must tell
DMAgic to start with the LAST address in the box, since it will now
be DECREMENTING by 1, and SUBTRACTING the MODULO when it gets to the
end of a row. DESCENDING mode can be selected individually for the
source and/or the destination by setting D_DIR and/or S_DIR in
CMD_LO, the command byte. We chose DOWN for both by adding 32 and 16
to the COPY command in line 360.
One more detail to notice in line 360 is that we are COPYing the box
from the SRC to the SRC, or copying in place, performing a BARREL
SHIFT of its pixels. The bit-barrel shifter is a device that allows
for movement of images on pixel boundaries, even though the pixels
are addressed 8 at a time by each byte address of the bit-plane
image. In this example of a SHIFT-LEFT-BY-1, the barrel shifter will
slide the seven rightmost bits to the left and shift a zero into the
vacated rightmost bit location. Zeros are shifted in for only the
first byte in a row. For each subsequent byte in the same row, the
data shifted out from the previous byte is shifted in. This way our
image not only can slide by pixels within a byte, but it can be
shifted out into the next adjoining byte resulting in a smooth scroll
of the image across the screen.
A. C64DX DEVELOPMENT SOPPORT
Please photocopy the attached 'C64DX PROBLEM REPORT' and use it to
report any problems.
If you have any requests or recommendations, please send a good
description of it and explain why you want it.
+----------------------------------------+-------------------------------------+
| C64 DX PROBLEM REPORT | Date |
+----------------------------------------+-------------------------------------+
|Please complete this form as completely as possible and mail or express it to:|
| |
| Commodore Business Machines, Inc. Telephone: 215-431-9427 |
| 1200 Wilson Drive Fax: 215-431-9156 |
| West Chester, PA I9380 Email: [email protected] |
| |
| Attention: Fred Bowen, Engineering |
+------------------------------------------------------------------------------+
|Company Name |
+------------------------------------------------------------------------------+
|Company Address |
| |
| |
| |
| |
| |
| |
| |
+----------------------------------------+-------------------------------------+
|Your Name |Your Phone |
+----------------------------------------+-------------------------------------+
|Your system |
| |
| Serial No.________ PCB rev_________ Software ver________ ROM Cksum__________ |
| |
| 4510 rev__________ 4567 rev________ F011(DOS)___________ F018(DMA)__________ |
| |
| Peripherals: |
+---------------------+--------------------------------------------------------+
|Your problem | Explain problem here and show how to cause it. Attach |
| | sample program. |
| ____ C64 mode | |
| ____ C64DX mode | |
| ____ Hardware | |
| ____ Software | |
| ____ Mechanical | |
| ____ Documentation | |
| ____ Compatibility | |
| | It happens: |
| | ____ all the time ____ frequently ____ occasionally |
+---------------------+--------------------------------------------------------+
|In your opinion, how I bad is the problem? ____ Must fix, no workaround |
| |
| ____ I can work around it |
| |
| ____ Check here if you need to be contacted ____ Minor problem |
+------------------------------------------------------------------------------+
|Please leave this space blank |
| |
| |
| |
| |
| |
|Number Received Contacted Completed |
+------------------------------------------------------------------------------+
B. C64DX System Specification UPDATE
(*TODO*: integrate into document)
* The Monitor parser now allows PETSCII input/conversion:
'A prints ASC() value of character
>1800 'text puts text into memory
LDA #'A
* IRQ runs during graphics (Kernel finds its own base page). IRQ
still does not run during DOS activity (not sure if they ever
will).
* The following Kernel Jump Table Entries have moved (and are still
subject to further changes):
FF05 nirq ;IRQ handler
FF07 monitor_brk ;BRK handler (Monitor)
FF09 nnmi ;NMI handler
FF0B nopen ;open
FF0D nclose ;close
FF0E nchkin ;chkin
FF11 nckout :ckout
FF13 nclrch ;clrch
FF15 nbasin :basin
FF17 nbsout ;bsout
FF19 nstop ;stop key scan
FF1B ngetin ;getin
FF1D nclall ;clall
FF1F monitor_parser ;monitor command parser
FF21 nload ;load
FF23 nsave ;save
FF25 talk
FF27 listen
FF29 talksa
FF2B second
FF2D acptr
FF2F ciout
FF31 untalk
FF33 unlisten
FF35 DOS_talk
FF37 DOS_listen
FF39 DOS_talksa
FF3B DOS_second
FF3D DOS_acptr
FF3F DOS_ciout
FF41 DOS_untalk
FF43 DOS_unlisten
FF45 Get_DOS
FF47 Leave_DOS
FF49 ColdStartDOS <<<new
FF4B WarmStartDOS <<<new
(*TODO* integrate into document start)
2.1.2. German/Austrian Reyboard Layout
+----+ +----+----+----+----+ +----+----+----+----+ +----+----+----+----+
|RUN | |ESC |ALT |ASC | NO | | F1 | F3 | F5 | F7 | | F9 | F11| F13|HELP|
|STOP| | | |DIN |SCRL| | F2 | F4 | F6 | F8 | | F10| F12| F14| |
+----+ +----+----+----+----+ +----+----+----+----+ +----+----+----+----+
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
| <| ! | " | # '| $ | % | & | ' /| ( | ) | " | ? | ` | ^ |CLR |INST|
|PI >| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | + �| - '| � [|HOME|DEL |
+----+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+----+
| TAB | | | | | | Z | | | | | � | | \ | RSTR |
| | Q | W | E | R | T | Y | U | I | O | P | @ | * +| ^ ]| |
+----+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+------+
|CTRL|SHFT| | | | | | | | | | � | � | ' | RETURN |
| |LOCK| A | S | D | F | G | H | J | K | L | : [| ; ]| = #| |
+----+----+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+--+-+----+----+----+
| C= | SHIFT | Y | | | | | | | < ;| > :| ? _| SHIFT|CRSR|
| | | Z | X | C | V | B | N | M | , | . | / -| | UP |
+----+-------+-+--+----+----+----+----+----+----+----+----+-+--+-+----+----+----+
| | |CRSR|CRSR|CRSR|
| | |LEFT|DOWN|RITE|
+--------------------------------------------+ +----+----+----+
Notes:
1/ The operation of national keyboards is identical to C128
implementation. The ASCII/DIN key replaces the CAPS LOCK key, and
can be toggled anytime to switch keyboard modes and automatically
change the display.
2/ The national keyboard contains key legends for both national and
ASCII modes. The national legends appear on the right top/bottom of
the keys.
3/ The German keyboard has three (3) "deadkeys". They are accent
d'aigue, accent grave, and accent circonflex. Pressing the
"deadkey" followed by a valid vowel or accent character will
'build' the desired character:
accent d'aigue: (*TODO*)
accent grave: (*TODO*), (*TODO*), (*TODO*)
accent circonflex: (*TODO*), (*TODO*), (*TODO*), (*TODO*), (*TODO*)
4/ National character ROM graphic characters differ from the C64 and
ASCII (English) graphic character sets.
PAINT x, y [,color]
Working, but not completely to spec. Uses draw pen
color and fills emptyness to any border.
RND(0) Improved for better "randomness". Uses unused POT of
second SID chip. PCB must allow lines to float.
SET DISK # (without [TO #] parameter) allows user to clear DS$
message and specify which drive next DS$ comes from.
SET VERIFY <ON/OFF>
The new DOS65 defaults to verify-after-write OFF. This
command works with 1581 drive, too.
* Negative coordinates are now allowed for all graphics commands.
Some commands require their arguments to be "onscreen" such as
PAINT.
* BASIC errors now force text mode, and TYPE, LIST, DISK, KEYLOAD,
LOADIFF now catch all DOS errors. Autoboot filename=AUTOBOOT.C64DX.*
* Opening an RS-232 channel, command string allows setting new
features:
1 baud (0-16, where 16=MIDI rate)
2 word len
3 parity
4 stop bits (not used)
5 duplex
6 xline
7 xon char (0=incoming flow control disabled)
8 xoff char (0=outgoing flow control disabled)
9,10 input buffer pointer (page lo, hi)
11,12 output buffer pointer (page lo, hi)
13 high water mark (point at which xoff is xmitted)
14 low water mark (point at which xon is xmitted)
For debug purposes, the border color will change if an RS232 buffer
overflow occurs. To differentiate between a GET# of a null and a
'no data' null, test bit 3 of STatus (same as C64).
* Support for latest DOS controller chip, F011D, includes error LED
blink (border color still changes too, for now). Changes to
improve FASTLOAD speed and improve SAVE speed. Will work with
F011C chip, but error LED does not blink. Requires latest 'ELMER'
PAL for disk LED to work correctly for either controller Chip.
External drive LED will not work correctly until new PCB & F016
chip are designed. New DOS functions include COPY D0 TO D1,
ability to change sector skews for files (U0>S#) and directory
(U0>D#), and directory compress (i.e., empty trash) via "E"
command. Physical interleave is now 7.
* The DOS COPY/CONCAT bugs have been fixed, and COPY now allows
forms such as COPY D0,"*.SRC" TO D1,"*" and COPY D0,"*=SEQ" TO D1,
"*". Directory/partition paths not yet implemented, but will be.
The following changes/updates/fixes have been made to the C64DX ROM
code since the March 1, 1991 C64DX System Specification was printed.
Please make note of them. Current ROM as of this update is 910501.
CHAR Now works to spec. and supports the following imbedded
control characters (although some are buggy; others are
planned):
^F 6 flip
^I 9 invert
^O 15 overwrite
^R 18 reverse field on
146 reverse field off
^U 21 underline
^Y 25 tilt
^Z 26 mirror
When specifying a character set from ROM, note that
national versions of the C64DX will have the national
character set at $39000 and the C64 character set at
$3DC00. In US/English systems, the default C64DX-mode
character set will be at $39000.
CLR ERR$ Clears BASIC error stuff, useful after a TRAP.
CURSOR [<ON/OFF>,] [column] [,row] [,style]
where: column,row = x,y logical screen position
style = flashing (0) or solid (1)
ON, OFF = to turn the cursor on or off
LINE x0, y0 [, [x1] [,y1]] ...
where: (x1,y1)=(x0,y0) if not specified, drawing a dot.
Additional coordinates (x2,y2), etc. draw a line
from the previous point.
LOADIFF "file" [,U#,D#]
Loads an IFF picture from disk. Requires a suitable graphic
screen to be already opened (this may change). The file must
contain std IFF data in PRG file type. IFF pics can be ported
directly from Amiga (eg., using XMODEM). Returns 'File Data
Error' if it finds data it does not like.
MOD (number, modulus)
New function.
MOUSE ON [,[port] [,[sprite] [,[hotspot] [,X/Yposition] ]]]
MOUSE OFF
where: port = (1...3) for joyport 1, 2, or either (both)
sprite = (0...7) sprite pointer
hotspot = x, y offset in sprite, default 0,0
position = normal, relative, or angular coordinates
Defaults to sprite 0, port 2, last hotspot (0,0), and
position. Kernel doesn't let hotspot leave the screen.
SYS 58552 (in C64 mode) - enter C65 mode
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