Developing for extremely old computers is a chore; not only are you limited by assembly or pure machine language, there’s also the issue of burning ROMs to actually run your programs. [Frank Buss] came up with a neat solution to developing for the venerable 4004 CPU – build a ROM emulator using a modern microcontroller.
The build started off with a ZIF socket for the 4004 CPU and a 256 byte 4001 ROM chip emulated on a PIC micro. The CPU looked a little lonely sitting in the ZIF socket all by its lonesome, so [Frank] updated his board to allow a 4002 RAM chip to be plugged in as well.
Because [Frank] chose a 4004 for his entry for this season’s retrochallenge competition, we need to point we’re offering a prize for loading our retro site with this CPU. Yes, it’s most likely impossible but nothing worth doing is easy.
You can check out a video [Frank]’s ROM emulator after the break.
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