Peter Ped Helcmanovsky ped7g

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ZX Spectrum Next is here, panic!

happy in assembly land

ped7g / Make Tap from assembly fix

Created July 29, 2020 07:36

fixed + cleaned up a bit source from Alexander

	REAL_ORG = #3c51
	DICT_BEGIN = #3c49
	DATA_REG = 129
	CONTROL_REG = 128
	RTS_LOW = #16
	RTS_HIGH = #56

	MACRO CHECKSUM start?
	opt push listoff ; disable listing while calculating checksum
	.ptr = start?

ped7g / ECHO.asm

Created May 24, 2020 20:02

sjasmplus version of ZX Spectrum Next dot command "ECHO"

	OUTPUT "ECHO"
	ORG 8192
	Start: ex de,hl
	ld a,d
	or e
	ret z ; DE == 0, no pointer to arguments
	Print: ld a,(de)
	or a
	ret z ; zero byte end of command line
	cp 13

ped7g / limitHlValue.asm

Last active March 5, 2020 16:42

Z80 routine to clamp value in HL to -0x100 to +0x100 range

	LimitHlValue:
	; In: HL = value to be clamped to -0x100 .. +0x100
	; Out: HL = clamped value
	; Uses: A + flags
	; (this is not mathematically correct, values 0x7F?? clamp to -0x100, for performance reasons)
	ld a,h
	inc a
	sra a ; will be 0 for -256..+255 (+256 will get "clamped")
	ret z
	ld hl,0x100

ped7g / zx_next_detect_video_mode.asm

Created October 29, 2019 16:18

utility routines for ZX Spectrum Next (mostly to detect current video mode) (not tested properly yet)

	; syntax for https://github.com/z00m128/sjasmplus/releases assembler
	OPT --syntax=abfw --zxnext

	;;----------------------------------------------------------------------------------------
	;; reads nextreg in A into A

	ReadNextReg:
	; Input
	; A = nextreg to read
	; Output:

ped7g / border_fallback_default.asm

Created July 15, 2019 22:15

	DEVICE ZXSPECTRUM48
	OPT reset --zxnext=cspect --syntax=abfw
	ORG $8000
	start:
	;; FIRST test: black border configured into default transparency fallback colour, inkmask 7
	; black border
	xor a
	out (254),a
	; configure the NextULA palette (inkmask 7, select ULA palette for write, display first pals, enable NextULA mode)
	nextreg $42,$07 ,, $43,%0'000'0'0'0'1

ped7g / fixed_point_math_example_x86_64_linux.asm

Created March 15, 2018 00:45

x86_64 linux asm example of fixed-point arithmetic

	; (C) [copyleft] 2018 Peter Helcmanovsky
	; License: CC0 https://creativecommons.org/share-your-work/public-domain/cc0
	;
	; x86_64 linux asm example of fixed-point arithmetic
	; (see https://en.wikipedia.org/wiki/Fixed-point_arithmetic)
	;
	; to build I'm using nasm and ld:
	; nasm -f elf64 %f -l %n.lst -w+all; ld -b elf64-x86-64 -o %n %n.o
	; (where %f is source file name and %n is just the main part w/o extension)
	;