Steve,
That sounds bogus. I'd have to check and I'm not at home.
Memory says that the 2708 was one of the first with the
relatively easy program sequences but the 1mS*100 sounds
strange for that part.
Allison
-----Original Message-----
From: Loboyko Steve <sloboyko(a)yahoo.com>
To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org>
Date: Monday, May 06, 2002 11:38 AM
Subject: 2708 Programming Algorithm?
I obtained a bunch of 2708 UVEPROM's, and I'd
like to
be able to program them. As you may know, they require
a different algorithm than the 2716 and on, and three
voltages, +5, +12, and -5.
I'm building a little board that will program 1/2 (the
upper or lower) of a 2716 to a 2708 (I can program
2716's). But I can't find a description of the
algorithm that is detailed enough. What I think I know
is:
1. The /OE line must be high
2. select address and data (start at addr 0)
3. bring PGM line from 0 to 27 volts for 1 mSec, then
drop back to 0 (this seems very strange)
4. repeat 100 times per address (not all at once,
increment the address lines and loop to avoid
"overheating" a byte.
5. drop /OE and verify.
Does anybody have an authoritative description, and a
current requirement for the +5, +12, -5, and
programming pulse? Thanks.
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