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Help with wiring an adapter for 27c128 (28pin 128k eprom)


New Member
Hi there,

I have a really old 27c128 eprom that is faulty so i'd like to burn a replacement.

The 28 pin adapter doesnt appear to wired correctly to support this eprom as what would be A14 on the supported devices (27c512 for example) is #PGM.

I can add the support for the EPROM to the source no problem but to save some trial and error does anyone know what pin on the 56pin header the #PGM pin connects to?

Perhaps rewire it to the existing pin20? then i'm wondering what to do with that pin.. perhaps CE0? Any help is appreciated.

I have attached a diagram of the EPROM.




  • eprom.png
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New Member
Hey thanks, yeah I was referring to that. There is no _PGM pin on the header.. looking at the other adapters I believe the pin labelled WE is the one I should be using, ill make up a protoboard and test it out.