INES Mapper 226
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Here are Disch's original notes: ======================== = Mapper 226 = ======================== Example Games: -------------------------- 76-in-1 Super 42-in-1 Registers: --------------------------- Range, Mask: $8000-FFFF, $8001 $8000: [PMOP PPPP] P = Low 6 bits of PRG Reg M = Mirroring (0=Horz, 1=Vert) O = PRG Mode $8001: [.... ...H] H = high bit of PRG PRG Setup: --------------------------- Low 6 bits of the PRG Reg come from $8000, high bit comes from $8001 $8000 $A000 $C000 $E000 +-------------------------------+ PRG Mode 0: | <Reg> | +-------------------------------+ PRG Mode 1: | Reg | Reg | +---------------+---------------+
The original describing document states the 2s bit of the register at $8001 disables CHRRAM writes. No games seem to rely on it, though. It also says that the mapper hardware is made of a 74LS74A, 74LS273, 74LS139, 74LS02, and 74LS153.
The multicart reportedly relies on the value of uninitialized memory to determine exactly how many games are available.
The multicart clears both registers on soft reset.
See also: Repair of one such cartridge
At least three different games using this mapper exists: 42 in 1 (1MB) 63 in 1 (1.5MB) 76 in 1 (2MB)
They appear in different ROM package and count configurations: