INES Mapper 189
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Here are Disch's original notes: ======================== = Mapper 189 = ======================== Example Game: -------------------------- Thunder Warrior Notes: --------------------------- This mapper is a modified MMC3. Everything operates just as it does on the MMC3, only the normal PRG regs (R:6,R:7) are ignored, and a new PRG Reg is used instead. For details on MMC3, see mapper 004 Registers: --------------------------- Regs at $6000-7FFF means no SRAM $4120-7FFF: [AAAA BBBB] A,B: PRG Reg $8000-FFFF: Same as on MMC3 PRG Setup: -------------------------- 'A' and 'B' bits of the $4120 reg seem to be effectively OR'd. That is... $30, $03, and $21 will all select page 3 $8000 $A000 $C000 $E000 +-------------------------------+ | $4120 | +-------------------------------+