INES Mapper 071

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iNES Mapper 071 is assigned to games developed by Codemasters and published by Camerica. It's largely a clone of UNROM, and Camerica games were initially emulated under iNES Mapper 002 before 071 was assigned.

Overview

  • PRG ROM size: 128 or 256 KiB
  • PRG ROM bank size: 16 KiB inner; ( 64 KiB outer in iNES Mapper 232 )
  • PRG RAM: None
  • CHR capacity: 8 KiB RAM
  • CHR bank size: Not bankswitched
  • Nametable mirroring: Hardwired H or V (most) or mapper controlled 1-screen (Fire Hawk)
  • Subject to bus conflicts: No

Banks

  • $8000-$BFFF: Switchable
  • $C000-$FFFF: Fixed to last bank
  • $8000-$FFFF: In the "Quattro" games, A16 and A17 are controlled by a separate register, allowing 64 KiB super-banks.

Registers

Outer bank select ($8000-$BFFF) (Only on iNES Mapper 232)

This register is present only on the Quattro carts, which use the BF9096 IC, and on the CCU in the Aladdin adapter (per KH)

7  bit  0
---- ----
xxxB Bxxx
   | |
   +-+--- Select 64 KiB PRG ROM bank for CPU $8000-$FFFF

Mirroring ($8000-$9FFF)

This register is present only on Fire Hawk, which uses the BF9097 IC. A submapper has been allocated for this difference.

7  bit  0
---- ----
xxxM xxxx
   |
   +----- Select 1 KiB CIRAM bank for PPU $2000-$2FFF

Bank select ($C000-$FFFF)

This register is present on all games: BF9093 (most common), BF9096, BF9097, and CCU. The number of bits available vary: 4 for the BF9093, 3 for the BF9097, and 2 for the BF9096.

7  bit  0
---- ----
xxxx PPPP
     ||||
     ++++- Select 16 KiB PRG ROM bank for CPU $8000-$BFFF

CIC stun control ($E000-$FFFF)

This register is present on all games. A0 controls a latch going to the CIC stun circuit.

See also