HP-75 EPROM Programming Info Needed


I have come across a dozen or so EPROMS for the HP-75. But I don't have much info on these. They are marked "CMT - FOXCONN" and the EPROM itself is marked 27C256 (32K x 8). Anyone have any info on these?

Does anyone have any plans for an eprom programmer for these? I notice that there is a 3 pin access on the back. I assume that is for programming.


I dont have any info on the module but the 27C256 is a fairly common EPROM a Data sheet can be found at : http://www.rigelcorp.com/doc/8051/27C256.pdf

presumably the three pins at the back are for providing the 13V programming voltage to burn it

Richard Freeman

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