NES 2.0 Mapper 403

NES 2.0 Mapper 403 denotes the 89433 circuit board with up to 1 MiB PRG-ROM and 32 KiB of CHR-RAM, bankable with 8 KiB granularity.

• Tetris Family - 玩家 19-in-1 智瑟實典 (NO-1683)
• Sachen Superpack (versions A-C)

PRG bank register ($4100)

Mask: $E103

D~[.PPP PPp.]
    +++-+++--- PRG A19..A14

Power-on value: $00

CHR bank register ($4101, $8000-$FFFF)

Mask: $E103, $8000

D~[.... ..CC]
          ++-- CHR A14..A13

Power-on value: $00

The latch at $8000-$FFFF is enabled/disabled via the Mode register's C bit.

Mode register ($4102)

Mask: $E103

D~[...H .C.N]
      |  | +- 0: PRG A14=CPU A14 (NROM-256)
      |  |    1: PRG A14=p (NROM-128)
      |  +--- 0: Latch at $8000-$FFFF disabled
      |       1: Latch at $8000-$FFFF enabled
      +------ 0: Vertical mirroring
              1: Horizontal mirroring

Power-on value: $00