Quote:
Originally Posted by TonyDuell
My first homebrew EPROM programmer was a couple of boards of TTL, ...
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My first, and only, homebrew EPROM programmer was a 74121 monostable, a transistor, some resistors, a capacitor, and three PP3 batteries.
The 2716 EPROM sat on the address and data busses of my ZX81. I can remember vaguely how it worked. The 74121 HALTed the CPU while making the programming pulse, so from the CPU's point of view it was just writing data to addresses.
I programmed lots of EPROMs with that little board. I wonder where it's gone now ?.