NES 2.0 Mapper 302

From NESdev Wiki
Jump to navigationJump to search

NES 2.0 Mapper 302 is used for Kaiser's ROM cartridge conversion of the Japanese Famicom Disk System version of Gyruss. Its UNIF board name is UNL-KS7057.

Banks

  • CPU $6000-$67FF: 2 KiB switchable PRG-ROM bank
  • CPU $6800-$6FFF: 2 KiB switchable PRG-ROM bank
  • CPU $7000-$77FF: 2 KiB switchable PRG-ROM bank
  • CPU $7800-$7FFF: 2 KiB switchable PRG-ROM bank
  • CPU $8000-$87FF: 2 KiB switchable PRG-ROM bank
  • CPU $8800-$8FFF: 2 KiB switchable PRG-ROM bank
  • CPU $9000-$97FF: 2 KiB switchable PRG-ROM bank
  • CPU $9800-$9FFF: 2 KiB switchable PRG-ROM bank
  • CPU $A000-$BFFF: 8 KiB fixed PRG-ROM bank #$0D
  • CPU $C000-$FFFF: 16 KiB fixed PRG-ROM bank #$07
  • PPU $0000-$1FFF: 8 KiB unbanked CHR-RAM

Registers

Mirroring select ($8000-$9FFF)

Mask: unknown, probably $E000

D~7654 3210
  ---------
  .... ...M
          +- Select nametable mirroring type
             0: Vertical
             1: Horizontal

PRG-ROM Bank ($B000-$E003)

Mask: unknown, probably $F003

A~FEDC BA98 7654 3210
  -------------------
  1RRR .... .... ..RN
   |||             |+- 0: Select low nibble
   |||             |   1: Select high nibble
   +++-------------+-- Select register number
                       $B000/$B001: Set 2 KiB PRG-ROM bank at CPU $8000-$87FF
                       $B002/$B003: Set 2 KiB PRG-ROM bank at CPU $8800-$8FFF
                       $C000/$C001: Set 2 KiB PRG-ROM bank at CPU $9000-$97FF
                       $C002/$C003: Set 2 KiB PRG-ROM bank at CPU $9800-$9FFF
                       $D000/$D001: Set 2 KiB PRG-ROM bank at CPU $6000-$67FF
                       $D002/$D003: Set 2 KiB PRG-ROM bank at CPU $6800-$6FFF
                       $E000/$E001: Set 2 KiB PRG-ROM bank at CPU $7000-$77FF
                       $E002/$E003: Set 2 KiB PRG-ROM bank at CPU $7800-$7FFF