NES 2.0 Mapper 288

NES 2.0 Mapper 288 is used for two GKCX1 21-in-1 multicarts. Oddly, GoodNES 3.23b has them set to INES Mapper 133 even though it is entirely incompatible with that mapper.

Address latch

A~1... .... ..MP PCCC
              || |+++- Select 8 KiB CHR-ROM bank at PPU $0000-$1FFF
              |+-+---- Select 32 KiB CHR-ROM bank at CPU $8000-$FFFF
              -------- 0=V mirroring, 1=H mirroring