NES 2.0 Mapper 525

NES 2.0 Mapper 525 is used for mapper hacks of VRC2-using games. Specific known games include Kaiser bootleg versions of Contra and 月風魔伝 (Getsu Fūma Den). Its UNIF board name is UNL-KS7021A.

Registers

Mask: $F000

 $8000: [.... PPP.] - Select 16KiB PRG bank at $8000-$BFFF
 $9000: [.... ...M] - like VRC2, 0: Vertical Mirroring (PPU A10); 1: Horizontal Mirroring (PPU A11)

Mask: $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

Hardware

The 7021A PCB contains a 7400, a 7427, a 7432, a 7474, a 74139, a 74157, a 74174, two 74189s, and the two ROMs.

Notes

• Getsu Fūma Den PCB images and analysis: BBS