INES Mapper 095
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What's written below is suspect, because the Namco 108 mapper does not have C or P bits, and sacrificing 32kB of CHR ROM just for the ability to swap between 1ScA/1ScB/horizontal mirroring seems like a weird tradeoff.
Here are Disch's original notes: ======================== = Mapper 095 = ======================== aka -------------------------- MMC3 (modified) Example Game: -------------------------- Dragon Buster (J) Notes: --------------------------- This mapper is a modified MMC3. It behaves exactly like your normal MMC3, only mirroring is handled differently. For details on MMC3, refer to mapper 004. Regs: --------------------------- $8000: [CP.. .AAA] C = CHR Mode P = PRG Mode A = Address for $8001 This register operates exactly like it does on your normal MMC3. It is mentioned here because the 'C' bit has another usage for mirroring. The normal mirroring reg ($A000) is totally ignored, and the CHR regs select nametables: When 'C' is set: [ R:2 ][ R:3 ] [ R:4 ][ R:5 ] When 'C' is clear: [ R:0 ][ R:0 ] [ R:1 ][ R:1 ] For mirroring, only bit 5 of the CHR regs is significant. Bit 5 of the appropriate reg selects either NTA or NTB.