INES Mapper 071

From NESdev Wiki
Revision as of 01:34, 25 January 2011 by Zepper (talk | contribs)
Jump to navigationJump to search

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 KB
  • PRG ROM bank size: 16 KB inner
  • PRG RAM: None
  • CHR capacity: 8 KB RAM
  • CHR bank size: Not bankswitched
  • Nametable mirroring: Hardwired H or V (most) or mapper controlled 1-screen (Fire Hawk)
  • Subject to bus conflicts: ???

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.

Solder pad config

To do

Registers

Outer bank select ($8000-$BFFF)

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
---- ----
xxBB xxxx
  ||
  ++----- Select 64 KB PRG ROM bank for CPU $8000-$FFFF

Mirroring ($8000-$9FFF)

This register is present only on Fire Hawk, which uses the BF9097 IC.

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

Bank select ($C000-$FFFF)

This register is present on all games: BF9093 (most common), BF9096, BF9097, and CCU. On BF9096, only the low two bits are implemented. On BF9097, only the low three bits are implemented.

7  bit  0
---- ----
xxxx PPPP
     ||||
     ++++- Select 16 KB 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.

Pinout

                    BF9093
                    BF9096   BF9097
             ,-v-.
        +5V -|   |- CPU A14  CPU A14
NES /ROMSEL -|   |- A13      A13
    PRG /CE -|   |- PRG A15  PRG A15
    PRG A14 -|   |- PRG A16  CIRAM A10
         M2 -|   |- GND      PRG A16
         A0 -|   |- R/W      GND
         D0 -|   |- PRG A17  R/W
         D1 -|   |- CIC      CIC
         D2 -|   |- D4       D4
        GND -|   |- D3       D3
             `---'

References