17 Sep
2007
17 Sep
'07
4:53 a.m.
So the question of the minute is this, is it possible
to substitute a
27C256 for a smaller 27C128?
IIRC the difference between a 27256 and a 27128 is that 128 puts VPP
on pin 1 - this is normally held at +5V for read applications. The
256 puts A14 on pin 1.
So a 256 will usually work as a 128 (reading - programming is
different) however you will most likely have to program your
code into the TOP half of the 27256.
Dave
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
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