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PostPosted: Fri Jun 30, 2017 8:48 am 
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Joined: Tue Nov 23, 2004 9:35 pm
Posts: 608
tepples wrote:
Many mapper 7 games on the ANROM or AOROM board fall into "Requires CPU's value to prevail over the ROM's value" because they expect the PRG ROM to disable itself during writes. ANROM decodes PRG ROM with 74HC02, and AOROM uses a PRG ROM whose +CE is wired to CPU R/W.


Those games should be in a fourth category, Board's Hardware ensures that the CPU's value prevails over the ROM's value. That would describe every board that disables ROM on a CPU write.

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