kernalemu is a C reimplementation of the Commodore KERNAL API, combined with a 6502 emulator. It allows runnung cleanly written PET/C64/C128 etc. command line applications on the UNIX command line, like BASIC interpreters, assemblers, monitors and text adventures.
- Channel I/O API
- Devices 0 (keyboard) and 3 (keyboard) map UNIX stdin and stdout.
- Devices 4-7 writes the printer output to files
printer4.txt
etc. on disk. - Devices 8-15 goes through a basic Commodore DOS layer that maps to the UNIX filesystem. Reading and writing files, sending certain disk commands and loading the directory (
"$"
) is supported. - Devices 1 (tape) and 2 (tape or RS-232) are not supported.
- Time API: bridged to system time
- IEEE-488 API: not yet supported
kernalemu [options] file...
You have to specify one or more programs. They have to be in PRG format, i.e. the first two bytes of the file contain the load address. All files are loaded into the emulator's memory.
-start <addr>
: entry point-startind <addr>
: location of entry point vector-machine <machine>
: KERNAL API level, valid arguments arepet
(v1/2/3),pet4
(v4),c64
,ted
(C16, C116, Plus/4),c128
,c65
(default:c64
)-text
: assume PETSCII upper/lower; convert to ASCII-graphics
: assume PETSCII upper/graphics; do not convert (default)-columns <n>
: insert hard line breaks after columns
- If no machine is specified, it is autodetected from the load address.
- If no entry point is specified:
- If the program has a
SYS
BASIC header, the entry point is extracted from it automatically. - Otherwise, it defaults to the load address.
- If the program has a
There are several applications in the demo
subdirectory. Here is how to run them:
$ kernalemu demo/basic4.prg -start 0xd3b5 -machine pet4
*** COMMODORE BASIC 4.0 ***
31743 BYTES FREE
READY.
$ kernalemu demo/vic20basic.prg -startind 0xc000 -machine vic20
**** CBM BASIC V2 ****
28159 BYTES FREE
READY.
$ kernalemu demo/vic20basic.prg demo/vic20basic4.prg -startind 0xa000 -machine vic20
**** CBM BASIC V2 ****
28159 BYTES FREE
READY.
$ kernalemu demo/basic2.prg -startind 0xa000 -machine c64
**** COMMODORE 64 BASIC V2 ****
64K RAM SYSTEM 38911 BASIC BYTES FREE
READY.
$ kernalemu demo/simonsbasic.prg demo/basic2.prg -startind 0x8000
*** EXTENDED CBM V2 BASIC ***
30719 BASIC BYTES FREE
READY.
$ kernalemu demo/c16basic.prg -start 0x8000 -machine 264
?OUT OF MEMORY ERROR IN 0
READY.
TODO
$ kernalemu demo/c128basic.prg -start 0x4000 -machine c128
COMMODORE BASIC V7.0 122365 BYTES FREE
(C)1986 COMMODORE ELECTRONICS, LTD.
(C)1977 MICROSOFT CORP.
ALL RIGHTS RESERVED
READY.
$ kernalemu demo/assembler64.prg
CBM RESIDENT ASSEMBLER V080282
(C) 1982 BY COMMODORE BUSINESS MACHINES
OBJECT FILE (CR OR D:NAME):
This is the assembler Commodore used to build their ROMs. It will successfully build e.g. the C64 KERNAL source if you extract the files from the disk image and pass kernal
as the source file name:
echo "kernal.hex\r\r\rkernal" | kernalemu assembler64.prg
This will create kernal.hex
with the hex output. You can convert it to binary using:
tr '\r' '\n' < kernal.hex > kernal_lf.hex
srec_cat kernal_lf.hex -MOS_Technologies \
-offset -0xe000 \
-fill 0xaa 0x0000 0x1fff \
-o kernal.bin -Binary
The assembler sends the LST output to the printer, which you can find in the file printer4.txt
:
[...]
01727 EE13 ;INPUT A BYTE FROM SERIAL BUS
01728 EE13 ;
01729 EE13 ACPTR
01730 EE13 78 SEI ;NO IRQ ALLOWED
01731 EE14 A9 00 LDA #$00 ;SET EOI/ERROR FLAG
01732 EE16 85 A5 STA COUNT
01733 EE18 20 85 EE JSR CLKHI ;MAKE SURE CLOCK LINE IS RELEASED
01734 EE1B 20 A9 EE ACP00A JSR DEBPIA ;WAIT FOR CLOCK HIGH
01735 EE1E 10 FB BPL ACP00A
01736 EE20 ;
01737 EE20 EOIACP
01738 EE20 A9 01 LDA #$01 ;SET TIMER 2 FOR 256US
01739 EE22 8D 07 DC STA D1T2H
01740 EE25 A9 19 LDA #TIMRB
[...]
$ kernalemu demo/assembler128.prg -start 0x2000 -machine c128
C/128 6502 ASSEMBLER V022086
(C)1986 BY COMMODORE BUSINESS MACHINES
SOURCE FILE (SYNTAX: [DRIVE:]FILENAME) ?
TODO
$ kernalemu demo/vicmon.prg -startind 0x4002 -machine vic20
VIC20 MICROMON V1.2 BILL YEE 22 JAN 83
B*
PC IRQ SR AC XR YR SP
.; 404D 4391 22 33 00 00 FF
.
$ kernalemu demo/monitor64.prg -machine c64
B*
PC SR AC XR YR SP
.;C03D 22 00 C3 00 FF
.
$ kernalemu demo/fc3monitor.prg -machine c64
C*
PC IRQ BK AC XR YR SP NV#BDIZC
.;4024 0000 07 8D FF 00 FF *.*.....
.
$ kernalemu 1.Adventure\ Land.prg -machine vic20 -start 0x7F50
COMMODORE Presents:
***** ADVENTURE *****
(C) 1981
by Scott Adams,INC
Adventure number: 1
Version: 1/416
Want to restore
previously saved game?
This repository is maintained by Michael Steil, [email protected], www.pagetable.com.
Some of the code is derived from cbmbasic, see there for additional authors.
The license is 2-clause BSD.