28 Jun
2002
28 Jun
'02
9:14 a.m.
"Tony Duell" <ard(a)p850ug1.demon.co.uk> said:
I managed to get a HTEC "Kitty Card" 8031-based
system. 32K RAM, unknown
amount of program ROM, 8031 CPU and an AMD PALCE to do all the address
decoding. The PALCE will be a pain in the rear to decode - I don't have a
Universal Programmer so I can't just pull a JEDEC file out of it and run it
through JED2EQN anyway...
> "Fred Cisin (XenoSoft)"
<cisin(a)xenosoft.com> said:
> > On Thu, 27 Jun 2002, Tony Duell wrote:
> > > The board contained one large ASIC, so I couldn't figure out what it
was
> > The earlier (NOT "Deluxe") version
was available in a version of
discrete
> > TTL. It shouldn't be too hard for us to
find one, if you want to
check it
> > out.
> I'd be interested in having a look at one, too, maybe reverse engineer
it.
> Unfortunately there are only two options:
> Non destructive (pick a probe point and then go over the entire
board
looking for
connections, then draw up a schematic and build a clone on a
protoboard)
Why is doing this a problem? The time taken to trace out a schematic
in
this manner goes roughly as the square of the number of components (but
perhaps a smaller power), it's faster the more large components there are
(since those can be used in one way, and tie down a lot of signals). The
PC edge connector and drive connectors count as 'components' for this as
they indentify signals. I would estimate that a PCB of 20 TTL chips would take
a good afternoon
to trace out. Not that long. How many chips are there on the old Option
Board anyway? And where can I find one?
That's what I'd like to know,
too...
Later.
--
Phil.
philpem(a)dsl.pipex.com
http://www.philpem.dsl.pipex.com/