21 May
2008
21 May
'08
5:42 a.m.
On Tue, May 20, 2008 at 11:27:17AM -0700, Josh Dersch wrote:
I've dumped the ROMS on the handbuilt expansion
board. If you're
interested in taking a look, see
http://yahozna.dyndns.org/computers/pet. I've named them as the labels
on the EPROMS indicate. I've glanced through them, there are no ASCII
strings or anything to make them easy to identify. Haven't done a
disassembly yet...
I did a quick disassembly. I got pretty random stuff from A000.HEX,
but the other two had reasonable contents.
DOS.HEX is almost certainly some version of the "DOS Wedge".
MCM-9000.HEX has reasonable code, but I only found contents
up to 2K, but the code references constants up to 4K... either
my S-record tool lost half the data, or, given the hex file
size, half is missing.
It ends like this...
.$97e6 20 4c 98 jsr $984c
.$97e9 85 fd sta $fd
.$97eb 86 fe stx $fe
.$97ed 20 5d 98 jsr $985d
.$97f0 8d 92 02 sta $0292
.$97f3 8e 93 02 stx $0293
.$97f6 20 a4 98 jsr $98a4
.$97f9 20 60 98 jsr $9860
.$97fc 85 fb sta $fb
.$97fe 86 fc stx $fc
Between subroutines past $9800, and some tables referenced
earlier, and a complete lack of a reasonable end of the code,
I'd say that's only the half of it.
It was common to stuff code in 2K or 4K chunks between $9000
and $BFFF... the hex files, though, seem to only describe
2K chunks. Are your ROMs all 2K and some haven't been copied
yet?
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 21-May-2008 at 12:30 Z
South Pole Station
PSC 468 Box 400 Temp -77.3 F (-60.7 C) Windchill -114.4 F (-81.4 C)
APO AP 96598 Wind 10.3 kts Grid 27 Barometer 677.2 mb (10734 ft)
Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html