NES 2.0 Mapper 535

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NES 2.0 Mapper 535 is used for Whirlwind Manu's cartridge conversion (cartrige code LH53) of the Famicom Disk System Game 謎の村雨城 (Nazo no Murasamejō). Its UNIF board name is UNL-LH53.

Banks

  • CPU $6000-$7FFF: 8 KiB switchable PRG-ROM bank
  • CPU $8000-$FFFF: 32 KiB fixed PRG-ROM bank #3, except where overlaid by PRG-RAM
  • CPU $B800-$D7FF: 8 KiB fixed PRG-RAM bank
  • PPU $0000-$1FFF: 8 KiB unbanked CHR-RAM

Registers

IRQ register ($E000-$EFFF, write)

Mask: probably $F000

D~7654 3210
  ---------
  .... ..E.
         +-- 1= Enable counting

Writing to this register acknowledges a pending IRQ, and resets the counter to zero. When counting is enabled, the counter increases on every M2 cycle; upon reaching a value of 7560, an IRQ is generated (according to FCEUX source code).

PRG bank register ($F000-$FFFF, write)

Mask: probably $F000

Sets the 8 KiB PRG-ROM bank at CPU $6000-$7FFF.

Notes

  • The conversion retains all writes to the FDS sound channel registers, so an emulator could provide the expansion sound channel even though the original Whirlwind Manu cartridge did not.
  • Game progress cannot be saved.