5 Jan
2010
5 Jan
'10
7:08 p.m.
Josh Dersch wrote:
Decided to dust off an old software project -- at one point I was
working on a Tektronix 4051 emulator, a machine based on the Motorola
6800 CPU.
I've coded up a simple 6800 emulation & disassembler but I'm lacking
some simple 6800 code to test out its accuracy on "real" code. I'd like
to put it through its paces on a simple piece of hardware before
tackling the (mostly) undocumented quirks of the 4051. (It's much
easier to debug a hardware emulation when you're confident the CPU
emulation isn't the culprit...)
I thought the Altair 680 would be a good starting point but I can't for
the life of me find any dumps of the monitor/VTL ROMs on the 'net.
Anyone have any leads for these or other 680 software?
Thanks,
Josh
You might try the SWTP monitor, a slight variation on the original Motorola
MIKBUG monitor.
The SWTP manual is here:
http://www.opencores.org/websvn,filedetails?repname=System68&path=%2FSy…
The assembler code listing is in the back and appears to have been OCR'd, so it
could be mangled into source
form with a little effort. These monitors use a bit-bashed serial port on bit
lines of a 6820 with an external bit timer read off an input bit on the 6820.
Might be an annoyance to try to emulate but alternatively one could simply hook
into the base-level character read/write routines.
There might be more stuff at Michael Holley's SWTP site but I couldn't access
it a few minutes ago:
http://www.swtpc.com/
(I could send you my own monitor that I use with the 6800 but it's been awhile
since I used it .. also wrote an asm, disasm and simulator a few years ago.)