NES 2.0 Mapper 300

NES 2.0 Mapper 300 is used for Golden 190-in-1 multicart. Its UNIF board name is BMC-190in1. It is similar to INES Mapper 214 except that mirroring is selectable

Address latch ($8000-$FFFF)

Mask: $8000

A~FEDC BA98 7654 3210
  -------------------
  .... .... ...G GG.M
               | || +- Select nametable mirroring type
               | ||     0: Vertical
               | ||     1: Horizontal
               +-++--- Select 16 KiB PRG-ROM bank at CPU $8000-$BFFF mirrored at $C000-$FFFF
                       and 8 KiB CHR-ROM bank at PPU $0000-$1FFF