INES Mapper 095: Difference between revisions

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m (add complaint)
(Shades of TKSROM/TLSROM)
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[[Category:iNES Mappers]][[Category:MMC3-like mappers]]
[[Category:iNES Mappers]][[Category:MMC3-like mappers]]
What's written below is suspect, because the Namco 108 mapper does not have C or P bits, and sacrificing 32kB of CHR ROM just for the ability to swap between 1ScA/1ScB/horizontal mirroring seems like a weird tradeoff.
What's written below is suspect, because the Namco 108 mapper does not have C or P bits, and sacrificing 32kB of CHR ROM just for the [[iNES Mapper 118|TxSROM-like]] ability to swap between 1ScA/1ScB/horizontal mirroring seems like a weird tradeoff.


   Here are Disch's original notes:
   Here are Disch's original notes:

Revision as of 21:28, 13 June 2012

What's written below is suspect, because the Namco 108 mapper does not have C or P bits, and sacrificing 32kB of CHR ROM just for the TxSROM-like ability to swap between 1ScA/1ScB/horizontal mirroring seems like a weird tradeoff.

 Here are Disch's original notes:
 ========================
 =  Mapper 095          =
 ========================
 
 aka
 --------------------------
 MMC3  (modified)
 
 
 Example Game:
 --------------------------
 Dragon Buster (J)
 
 
 Notes:
 ---------------------------
 This mapper is a modified MMC3.  It behaves exactly like your normal MMC3, only mirroring is handled
 differently.  For details on MMC3, refer to mapper 004.
 
 
 Regs:
 ---------------------------
 
 $8000:  [CP.. .AAA]
    C = CHR Mode
    P = PRG Mode
    A = Address for $8001
 
 
 This register operates exactly like it does on your normal MMC3.  It is mentioned here because the 'C' bit
 has another usage for mirroring.
 
 
 
 The normal mirroring reg ($A000) is totally ignored, and the CHR regs select nametables:
 
 When 'C' is set:
    [ R:2 ][ R:3 ]
    [ R:4 ][ R:5 ]
 
 When 'C' is clear:
    [ R:0 ][ R:0 ]
    [ R:1 ][ R:1 ]
 
 
 For mirroring, only bit 5 of the CHR regs is significant.  Bit 5 of the appropriate reg selects either NTA or
 NTB.