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
Mask: $8000
A~FEDC BA98 7654 3210
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.... .... ...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