NES 2.0 Mapper 332

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NES 2.0 mapper 332 is used for the Super 40-in-1 and Super 500-in-1 multicarts. Its UNIF board name is BMC-WS.

PRG/Mirroring Register ($6000)

Mask: probably $E001

D~7654 3210
  ---------
  .H.M BPPp
   | | |+++- PRG A14..A16 for CPU $8000-$BFFF and $C000-$FFFF
   | | +---- Select PRG A14 Mode
   | |        0: PRG A14=CPU A14 (NROM-256)
   | |        1: PRG A14=p (NROM-128)
   | +------ Select nametable mirroring mode
   |          0: Vertical
   |          1: Horizontal
   +-------- Select PRG A17 and CHR A16
Reset value: $00

CHR/Solder Pad Register ($6001)

Mask: probably $E001

D~7654 3210
  ---------
  DDMM .Cdc
  ||||  |++- CHR A13..A14 for PPU $0000-$1FFF if MM=11
  ||||  +--- CHR A15
  ||++------ 00: CNROM-256 mode: CHR A13..A14 from CNROM latch
  ||         10: CNROM-128 mode: CHR A13 from CNROM latch, CHR A14 from d
  ||         11: NROM mode: CHR A13..A14 from dc
  ++-------- Solder pad check
Reset value: $00

The solder pads connect the latch output directly to PRG-ROM /CE. The menu code, executing from RAM, sets either bit to check whether CPU $8000-$FFFF now returns open bus, and selects a menu with different game counts depending on the result.

CNROM latch ($8000-$FFFF)

D~7654 3210
  ---------
  .... ..CC
         ++- CHR A13..A14 for PPU $0000-$1FFF if MM=00
Reset value: $00