I will note here that the Tristar 8000 hardware employs one of the lamest protections against ROM swaps ever devised. Basically each game's program code starts by reading the coin port and then locking up the CPU if bits 7 and 6 fail to match a constant value. This presumably is implemented by bridging the two corresponding input buffer pins to GND or Vcc; if so, it can be defeated with trivial wire mods.
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Re: more Eeekk! goodness
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