As for the
40-pin chip, unless it's something like a 6500/1 (a micro-
controller-like relative of the 6502, as found in the 1520 plotter),
Unless there's some EPROM/ROM in there, it's unlikely to be a
microprocessor. It might even be a gate array.
There is no ROM that I could see... Also, this chip is completely
unmarked - flat plack plastic DIP with no lettering.
Other apparent power sources from the connector head
off into a maze
of op-amps and other analog circuitry, even with schematics it would
take a bit of work to figure out what supplies it was designed for...
Hmm... that makes it hard.
Hard, but not impossible. It should be possible to trace the 5 pins of
that DIN socket. I'll bet one of them is ground (which you must be able
to find). You mention a regulator. Where does the output of that go
(+5V line to the lgoic). And does the input come from a pin on the DIN
socket (that should give you a good guess as to what goes in there). Now
look at the power pins to the op-amps. Maybe they go straing to the DIN
socket (in which case I'll go for +/-12V there). Maybe more regulators
(if so, do the inputs come from the DIN sockets). And so on. I suspect it
would be possible to come up with a supply that works.
Agreed that it's possible, and when I get the time I will go through it,
I was just explaining why it would be nice to have someone measure the
power supply pins so that I would have a starting place. I can basically
identify all of the pins on the power socket - but I heasitate to
assume +/-12 for the analog - It would be nice to at least have a no-load
measurement... If I can't find any information, it may come down to
doing what you suggest.
Regards,
Dave
--
dave04a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools:
www.dunfield.com
com Vintage computing equipment collector.
http://www.parse.com/~ddunfield/museum/index.html
