Hi all!
Just thought I'd bring your attention to some info I've put up on the web. It's a set of instructions to upgrade the Data I/O 29B programmer from 256K to 1Meg of memory:
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This will allow you to then do larger devices like 27c4001, 27c801
27c4096 etc if you have the right adaptors for the unipak 2B.
Yours, Mark.