"Tony Duell" <ard_at_p850ug1.demon.co.uk> said:
> > "Fred Cisin (XenoSoft)" <cisin_at_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 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...
> 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_at_dsl.pipex.com
http://www.philpem.dsl.pipex.com/
Received on Fri Jun 28 2002 - 16:14:42 BST