NES 2.0 Mapper 261: Difference between revisions
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[[Category:Multicart mappers]] | {{DEFAULTSORT:261}}[[Category:Multicart mappers]] | ||
NES 2.0 Mapper 261 was assigned by FCEUX for the '' | '''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= | ||
| Line 13: | Line 15: | ||
|| | 0: NROM-128 (16 KiB PRG-ROM at $8000-$BFFF, mirrored) | || | 0: NROM-128 (16 KiB PRG-ROM at $8000-$BFFF, mirrored) | ||
|| | 1: NROM-256 (32 KiB PRG-ROM at $8000-$FFFF) | || | 1: NROM-256 (32 KiB PRG-ROM at $8000-$FFFF) | ||
++-+--------- Select 32 KiB | ++-+--------- Select 32 KiB PRG-ROM bank in NROM-256 mode/ | ||
bits 1-3 of 16 KiB PRG-ROM bank in NROM-128 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. | The first game on that multicart, ''Elfland'', is actually a CNROM game that writes to the multicart address latch to switch CHR-ROM banks. | ||
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.
