Rick Carlino RickCarlino

Passing a Number to a Sequence

SCENARIO:

You have a sequence with an ID of 123.
The sequence exposes one numberic variable with a label of My number (capitalization is important).
You want to execute the sequence and pass a value of 456 to the variable.

Singly Linked List

This snippet provides a generic implementation of a singly linked list. Each value in the list points forward to the next item.

Currently only supports one list per VM, which is acceptable for my use case.

+------+
|LINK  |---*

+------+ |

dump - A Memory Inspector for RetroForth

Two words are provided below: a regular dump word, plus a dump-s word for dealing with strings.

Example output:

> #16 [ 'Hello,_world! s:put nl ] dump
3C4C: 0x801
3C4D: 0xE97

3C4E: H

OK

RETRO 12 (2021.7)
524288 Max, 14948 Used, 509340 Free
'hmmm s:hash n:put
2090333460
bye

:activate-burners 'Burners_ON s:put nl ;
:begin-timer 'Timer_SET s:put nl ;
:toaster.on-start hook ;
:activate-toaster toaster.on-start activate-burners begin-timer ;
:custom-callback 'Hello_from_my_callback s:put nl ;

Run without callbacks:

Multitasking in Retro

This is a beta feature. For early access, consider donating to the RetroForth Patreon.

High Level Overview

Retro exposes multitasking as an I/O device at the VM layer.

#900 'task:DEVICE_ID const

	1780 700 410
	1790 700 410
	1790 770 410
	1730 760 413
	1780 720 413
	1780 770 413
	1790 780 413
	1770 700 417
	1790 680 417
	1740 750 420

	1000 1000 450
	1000 1010 450
	1000 1020 450
	1000 1030 453
	1000 1040 450
	1000 1050 453
	1000 1060 450
	1000 210 443
	1000 220 447
	1000 230 447

	[ 0.000000] Booting Linux on physical CPU 0x0
	[ 0.000000] Linux version 5.10.9-v7+ (dom@buildbot) (arm-linux-gnueabihf-gcc-8 (Ubuntu/Linaro 8.4.0-3ubuntu1) 8.4.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #1396 SMP Thu Jan 21 15:54:00 GMT 2021
	[ 0.000000] CPU: ARMv7 Processor [410fd034] revision 4 (ARMv7), cr=10c5383d
	[ 0.000000] CPU: div instructions available: patching division code
	[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
	[ 0.000000] OF: fdt: Machine model: Raspberry Pi 3 Model B Rev 1.2
	[ 0.000000] earlycon: uart8250 at MMIO32 0x3f215040 (options '')
	[ 0.000000] printk: bootconsole [uart8250] enabled
	[ 0.000000] Memory policy: Data cache writealloc
	[ 0.000000] Reserved memory: created CMA memory pool at 0x37400000, size 64 MiB

	@wait_time 25
	# Base case: We have a pid
	def wait_for(pid) when is_pid(pid), do: continue_waiting(pid)
	# Failure case: We failed to find a pid for a module.
	def wait_for(nil), do: raise("Attempted to wait on bad module/pid")
	# Edge case: We have a module and need to try finding its pid.
	def wait_for(mod), do: wait_for(Process.whereis(mod))

	defp continue_waiting(pid) do
	wait(pid, Process.info(pid, :message_queue_len))