NES 2.0 Mapper 305

NES 2.0 Mapper 305 is used for Kaiser's ROM cartridge conversion of the Japanese Famicom Disk System version of ドラキュラII 呪いの封印 (Dracula II: Noroi no Fūin). Its UNIF board name is KS7031 (without any prefix).

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 fixed PRG-ROM bank #15
• CPU $8800-$8FFF: 2 KiB fixed PRG-ROM bank #14
• CPU $9000-$97FF: 2 KiB fixed PRG-ROM bank #13
• CPU $9800-$9FFF: 2 KiB fixed PRG-ROM bank #12
• CPU $A000-$A7FF: 2 KiB fixed PRG-ROM bank #11
• CPU $A800-$AFFF: 2 KiB fixed PRG-ROM bank #10
• CPU $B000-$B7FF: 2 KiB fixed PRG-ROM bank #9
• CPU $B800-$BFFF: 2 KiB fixed PRG-ROM bank #8
• CPU $C000-$C7FF: 2 KiB fixed PRG-ROM bank #7
• CPU $C800-$CFFF: 2 KiB fixed PRG-ROM bank #6
• CPU $D000-$D7FF: 2 KiB fixed PRG-ROM bank #5
• CPU $D800-$DFFF: 2 KiB fixed PRG-ROM bank #4
• CPU $E000-$E7FF: 2 KiB fixed PRG-ROM bank #3
• CPU $E800-$EFFF: 2 KiB fixed PRG-ROM bank #2
• CPU $F000-$F7FF: 2 KiB fixed PRG-ROM bank #1
• CPU $F800-$FFFF: 2 KiB fixed PRG-ROM bank #0
• PPU $0000-$1FFF: 8 KiB unbanked CHR-RAM

Registers

PRG-ROM Bank ($8000-$FFFF)

Mask: $8000

A~FEDC BA98 7654 3210
  -------------------
  1..R R... .... ....
     + +-------------- Select register number
                       $8000: Set 2 KiB PRG-ROM bank at CPU $6000-$67FF
                       $8800: Set 2 KiB PRG-ROM bank at CPU $6800-$6FFF
                       $9000: Set 2 KiB PRG-ROM bank at CPU $7000-$77FF
                       $9800: Set 2 KiB PRG-ROM bank at CPU $7800-$7FFF

Notes

• Mirroring is hard-wired to Vertical. One of the two common UNIF ROM images of this game has no MIRR chunk.
• Save data is not retained, even as one of the two common UNIF ROM images has a BATT chunk.
• The conversion retains all writes to the FDS sound channel registers, so an emulator could provide the expansion sound channel even though the original Kaiser cartridge did not.