INES Mapper 243

iNES Mapper 243 denotes the Sachen SA-020A circuit board. Using an eight-register ASIC with a fake "74LS374N" marking, it supports up to 128 KiB PRG-ROM, and 128 KiB of CHR-ROM. It is used for only one game, 美女拳 - Honey Peach (SA-006).

Banks

• CPU $8000-$FFFF: switchable 32 KiB PRG-ROM bank
• PPU $0000-$1FFF: switchable 8 KiB CHR-ROM bank
• Nametable mirroring: switchable H/V/L-shaped/One-screen

Registers

Register Index ($4100, write)

Mask: $C101

D~7654 3210
  ---------
  .... .RRR
        +++- Select register number (Rx)

Register Data ($4101, write)

Mask: $C101

D~7654 3210
  ---------
  .... .RRR
        +++- Register data

D~7654 3210
  ---------
  .... ...A  R2: CHR A13
  .... ...C  R4: CHR A14
  .... ..PP  R5: PRG A16..A15
  .... ..DC  R6: CHR A16..A15
  ...  .MM.  R7: Nametable mirroring
              0: Vertical
              1: Horizontal
              2: L-shaped: S0-S1-S1-S1
              3: Single-screen: S0

Registers 0/1/3 are completely unused.

Protection ($4100, read)

Mask: $C100

D~7654 3210
  ---------
  .... .RRR
        +++- Inverse of previous index

Errata

The SA-150 PCB, denoted by INES Mapper 150, connects the same ASIC differently, changing the meaning of the CHR-bank-related register bits.

See also

• Box, Cart, and PCB picture of Honey Peach