[sdiy] seek help on Jupiter 6 repair

[Anderson, Robert O]

From: Rainer Buchty [mailto:buchty at cs.tum.edu]
> Do they decay to 0xffs?
Yes. An empty EPROM contains 0xff.
However, I've never seen an EPROM decaying completely w/o being exposed to
UV light. Maybe that one was programmed with one of those "fast"
algorithms we all were so proud of back in the 80s ("look, it takes only
seconds, not minutes.")

Greetings ESQ. Rainer,
Those voice card 2732s were clean as a whistle, all 0xffs.  Seems strange to
me for a decaying effect, shouldn't there be some distribution in there?
They both have smooth silver Roland stickers over the windows.  The pins on
one of the chips looks kinda bent which made me a little suspicious but the
other one has nice straight leads.  I've  disassembled the controller file.

I'm thinking of writing a little voice card JUPOS to allow quick voice card
diagnosis.  Hook up my PC serial port through a MAX232 to each card and
twiddle bits.

Bob A