Re: Why can't 27C64 replace a 2764?

["Robert J. Stevens" <atreborz@execpc.com>]

Glenn Jones wrote:

> I am trying to read a 27C64 EPROM chip with my old apple 2 eprom programmer.
> It supports and reads 2764's fine but won't seem to read a 27C64. The pinouts
> are the same and both require 5v to read ...
> Any thoughts?
> Glenn

I am trying to read both 2764's and a 2716. I built a breadboard Reader and was
able to read out a AM27S19DC 32x8 Prom.
But using the same technique I can't get the 2716 to read it seems to be all
FF's.
Only got one so can't check with another chip.
I am going to stretch the wires to use a 2764 which I have a bunch.
[Old ones given to me by a friend so they might be programmed]
I see a 27c512 in the box and some 27128's
I have a Pro-Log M980 with a Personality Module 9080.
It accepts both 24 pin and 28 Pin Proms but I'm not sure what Chips it will read
and program.
If I can read a 2764 on my B/B then I may try to see if I can get the PRo to
read them.
If I measure the Pinouts I may be able to determine what Pins are Addresses and
what pins are Data
I am receiving and Old Apple ][ Prom Burner so that may help
Any Thoughts
Bob in Wisconsin