INES Mapper 066

iNES Mapper 066 refers to GxROM cartridge boards.

 Here are Disch's original notes:
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 =  Mapper 066          =
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 aka
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 GxROM and compatible
 
 
 Example Games:
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 Doraemon
 Dragon Power
 Gumshoe
 Thunder & Lightning
 Super Mario Bros. + Duck Hunt
 
 
 Notes:
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 I do not know whether or not this mapper suffers from bus conflicts.  Use caution!
 
 This mapper is INFAMOUS for having bad headers.  Probably 80% or more of these ROMs floating around out
 there have the wrong mirroring mode set in the header.
 
 Some games are marked as mapper 066 that are really mapper 140.  See mapper 140 for info.
 
 
 Registers:
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   $8000-FFFF:  [..PP ..CC]
     P = Selects 32k PRG @ $8000
     C = Selects 8k CHR @ $0000