INES Mapper 111

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Mapper 111 is used by Memblers' Cheapocabra GT-ROM 512k self-flashable board.

It is only well-defined for 512KiB PRG, 32 KiB CHR-RAM, and 4-screen nametables.

Mask: $D000
$5000: [grnc pppp]
        |||| ||||
        |||| ++++- Select 32 KiB PRG at CPU $8000-$FFFF
        |||+------ Select 8 KiB CHR RAM at PPU $0000-$1FFF
        ||+------- Select 8 KiB nametable and scratch RAM at PPU $2000-$3EFF
        |+-------- 0: red LED is lit, 1: off
        +--------- 0: green LED is lit, 1: off

Like iNES Mapper 030, the specific flash used on this board is the SST39SF040. Games are expected to use the chip's self-erase and self-write abilities for game saves.

The specific hardware on this board is a 74377, a 7402, and a 7410. The exact connectivity is not known, but the functions evaluated by the logic must include:

  • CHRRAMA14 = if (PPUA13==1) { n } else { c }
  • Latch on M2, /ROMSEL, A14, A12 high, and maybe on R/W low

Information: Membler Industries in 2015 - forum post describing the board.