INES Mapper 034: Difference between revisions
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{{DEFAULTSORT:034}}[[Category:iNES Mappers]][[Category:Mappers with CHR RAM]][[Category:Mappers with bus conflicts]] | {{DEFAULTSORT:034}}[[Category:iNES Mappers]][[Category:Mappers with CHR RAM]][[Category:Mappers with bus conflicts]] | ||
[[iNES Mapper 034]] is used to designate both the [[BNROM]] | [[iNES Mapper 034]] is used to designate both the [[BNROM]] and [[NINA-001]] boards. These two boards are unrelated, but have unfortunately been grouped into the same mapper. | ||
Emulator authors are suggested to distinguish between these two by checking the number of CHR banks present - BNROM should be used when there is 0 to 8 KiB of CHR, and NINA-001 should be used otherwise. | Emulator authors are suggested to distinguish between these two by checking the number of CHR banks present - BNROM should be used when there is 0 to 8 KiB of CHR, and NINA-001 should be used otherwise. | ||
Revision as of 15:33, 17 March 2014
iNES Mapper 034 is used to designate both the BNROM and NINA-001 boards. These two boards are unrelated, but have unfortunately been grouped into the same mapper.
Emulator authors are suggested to distinguish between these two by checking the number of CHR banks present - BNROM should be used when there is 0 to 8 KiB of CHR, and NINA-001 should be used otherwise. The NES 2.0 header with a submapper can be used to force use of NINA-001 behavior even with 8 KiB of CHR ROM or CHR RAM.
BNROM
See: BNROM
- PRG ROM size: 128 KB (mapper implementations may support up to 512 KB or 8 MB)
- PRG ROM bank size: 32 KB
- PRG RAM: None
- CHR capacity: 8 KB RAM
- CHR bank size: Not bankswitched
- Nametable mirroring: Solder pads select vertical or horizontal mirroring
- Subject to bus conflicts: Yes
Games:
- Deadly Towers (Mashou)
- Darkseed
Registers:
7 bit 0
---------
$8000-FFFF: .... ..PP - Select 32 KB PRG ROM bank
Emulators commonly support either a 4-bit or 8-bit register, enabling up to 512 KB or 8 MB PRG ROM. This variant may be referred to as BxROM.
NINA-001
See: NINA-001
- PRG ROM size: 64 KB
- PRG ROM bank size: 32 KB
- PRG RAM: 8 KB, not battery backed
- CHR ROM capacity: 32 KB ROM
- CHR bank size: 4 KB
- Nametable mirroring: hardwired to horizontal mirroring
- Subject to bus conflicts: No
Games:
- Impossible Mission 2
Registers::
7 bit 0
---------
$7FFD: .... ...P - Select 32 KB PRG ROM bank
$7FFE: .... CCCC - Select 4 KB CHR bank at $0000
$7FFF: .... CCCC - Select 4 KB CHR bank at $1000
