NES 2.0 Mapper 525

NES 2.0 Mapper 525 is used for the Kaiser bootleg versions of Contra and 月風魔伝 (Getsu Fūma Den). It's a VRC2 clone (with chip A0=CPU A0 chip A1=CPU A1, i.e. VRC2b, Mapper 23 Submapper 3) with non-nibblized CHR-ROM bank registers. Its UNIF board name is UNL-KS7021A.

CHR-ROM Bank Registers ($B000-$B007)

Mask: Probably $F007

• $B000: Select 1 KiB CHR-ROM bank at PPU $0000-$03FF
• $B001: Select 1 KiB CHR-ROM bank at PPU $0400-$07FF
• $B002: Select 1 KiB CHR-ROM bank at PPU $0800-$0BFF
• $B003: Select 1 KiB CHR-ROM bank at PPU $0C00-$0FFF
• $B004: Select 1 KiB CHR-ROM bank at PPU $1000-$13FF
• $B005: Select 1 KiB CHR-ROM bank at PPU $1400-$17FF
• $B006: Select 1 KiB CHR-ROM bank at PPU $1800-$1BFF
• $B007: Select 1 KiB CHR-ROM bank at PPU $1C00-$1FFF

PRG/Mirroring Registers ($8000-$AFFF)

See VRC2.

Getsu Fūma Den doesn't have a VRC2, but instead implements UNROM-style banking and the mirroring control in discrete logic.

Notes

• PCB images and analysis: BBS