Ralf Brandt said:
Ok, Thanks. I have that. It's the same as the AT28C17.
What I need to know is, what does all this mean, and
what all needs to be connected to ensure that the chip
is fully zapped. This is an excerpt from the AT28C17.PDF
I got from the net.
"CHIP CLEAR: The Contents of the entire memory of the
AT28C17 may be set to the high state by the CHIP CLEAR
operation. By Setting ~CE low and ~OE to 12 volts, the chip
is cleared when a 10 msec pulse is applied to ~WE."
The tilde in front of the signal references is actually an
overscore in the above quoted text.
What I need are examples of how these are applied to various
circuits, and/or even a hand drawn diagram of how I can
connect them in order to attain the required results.
I hate to throw these away because they have code on them
that I can't erase, and there are tons more I can acquire very
inexpensively, not to mention that many roms in older 8-bit
systems are 2k. I enjoy rewriting romware and seeing it being
implemented in ways that the creator of the system did not
intend. It's kool. Eproms are fine, but if I can have chips that
I can program in-line, then I can have even more fun.
Any more help that someone can offer will be greatly
appreciated.
Many Thanks in Advance,
Bill @ GarberStreet Enterprizez };-)
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