INES Mapper 095

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Mapper 95 represents NAMCOT-3425, a board that is to the ordinary Namco 108 family boards (mapper 206) as TKSROM and TLSROM (mapper 118) is to ordinary MMC3 boards (mapper 4). Instead of having hardwired mirroring like mapper 206, it has CHR A15 directly controlling CIRAM A10, just as CHR A17 controls CIRAM A10 on TxSROM. Only horizontal mirroring and 1-screen mirroring are possible because the Namco 108 lacks the C bit of MMC3. It is used for Dragon Buster (J), which has 32 KiB of CHR ROM. The mapper could be extended to 64 KiB through careful arrangement of CHR ROM to put game background tiles in one half (which would always use one nametable) and status bar and menu tiles in the other half (which would always use the other nametable).

Some emulators may support an extended version of this mapper with a full MMC3, described below in Disch's notes. This extended version is identical to mapper 118, except CHR A15 (bank bit 5) controls CIRAM A10 instead of CHR A17 (bank bit 7).

 ========================
 =  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.