kimdos

Commodore serial bus (IEC) disk access for the KIM-1, PAL-1/PAL-II and other replicas: a 6502 library, and a shell built on it, that load and save CBM DOS files on a 1541, an SD2IEC/uIEC or anything else that speaks the bus, with JiffyDOS for devices that have it. Written from the protocol, not from Commodore's code.

The library uses no zero page, preserves the user port's spare bits, and links anywhere with ld65; an llvm-mos C version comes with a KIM-1 platform for that compiler. The shell runs over the monitor's TTY:

KIMDOS
>S PROG,2000,290D
00, OK,00,00
>L PROG,4000
$4000-$490D
>$
1 "                " 32 2A
10   "PROG"             PRG
65535 BLOCKS FREE.
>S PROG,2000,2001
63,FILE EXISTS,00,00

Install

pip install kimdos
kimtape load --port /dev/ttyUSB0 https://github.com/anarkiwi/kimdos/releases/latest/download/kimdos-2000.ptp --go 2000

Each release has the shell at $0400, $2000 and $C000 (kimdos-<org>.ptp, .bin, .lbl), also in the package (kimdos.build.packaged); it needs about 2.5K of RAM there. The package ships the llvm-mos C library: python -m kimdos.clib prints its directory.

To build, with cc65: make ORG=2000 writes build/kimdos-2000.{bin,ptp,lbl,map} and build/kimdos.lib; make clib builds build/c/libkimdos.a with llvm-mos in docker.

Shell

Names may be quoted. From the keypad, put the KIM tape ID in $17F9 and run ORG+3 to load the file named by its two hex digits, or set $17F5-$17F8 as for a tape save and run ORG+6 to save.

Simulator

kimdos sim --dir ./disk           # the shell against .prg files in ./disk
kimdos sim --no-jiffy             # against a drive without JiffyDOS
kimdos bench                      # cycles per byte and JiffyDOS margins
kimdos board --port /dev/ttyUSB0 --install '$' '@'

Documentation

• docs/hardware.md — the adapter and its wiring
• docs/library.md — linking the library into a program, the API
• docs/clibrary.md — the llvm-mos C library and KIM-1 platform
• docs/protocol.md — the bus protocol as implemented
• docs/development.md — tests, the simulator, releases