NES 2.0 Mapper 261: Difference between revisions

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[[Category:Multicart mappers|261]]
{{DEFAULTSORT:261}}[[Category:Multicart mappers]]
NES 2.0 Mapper 261 was assigned by FCEUX for the ''200-in-1 - Elfland'' multicart. Its UNIF board name is '''BMC-810544-C-A1'''.
'''NES 2.0 Mapper 261''' was assigned by FCEUX for the '''810544-C-A1''' and '''NTDEC 2746''' multicart circuit boards. Its UNIF board name is '''BMC-810544-C-A1'''.
* ''200-in-1 - Elfland''
* ''14-in-1'' (NTDEC)


=Address latch=
=Address latch=

Latest revision as of 15:02, 18 December 2021

NES 2.0 Mapper 261 was assigned by FCEUX for the 810544-C-A1 and NTDEC 2746 multicart circuit boards. Its UNIF board name is BMC-810544-C-A1.

  • 200-in-1 - Elfland
  • 14-in-1 (NTDEC)

Address latch

A~1... ..PP PmpM CCCC
         || |||| ++++- Select 8 KiB CHR-ROM bank at PPU $0000-$1FFF
         || |||+------ Select nametable mirroring type
         || |||         0: Vertical
         || |||         1: Horizontal
         || ||+------- Lowest bit of 16 KiB PRG-ROM bank number
         || ||         at CPU $8000-$BFFF/$C000-$FFF in NROM-128 mode
         || |+-------- PRG-ROM banking mode
         || |           0: NROM-128 (16 KiB PRG-ROM at $8000-$BFFF, mirrored)
         || |           1: NROM-256 (32 KiB PRG-ROM at $8000-$FFFF)
         ++-+--------- Select 32 KiB PRG-ROM bank in NROM-256 mode/
                       bits 1-3 of 16 KiB PRG-ROM bank in NROM-128 mode

The first game on that multicart, Elfland, is actually a CNROM game that writes to the multicart address latch to switch CHR-ROM banks.