INES Mapper 074

iNES Mapper 074 is a MMC3 clone used in Eastern games. It's identical to iNES Mapper 192 and used for the same reason, except that only pages 8 and 9 are RAM. If the NES 2.0 header is present, 74 and 192 should be emulated identically, as NES 2.0 specifies CHR RAM size elsewhere.

 Here are Disch's original notes:
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 =  Mapper 074          =
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 aka:
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 Pirate MMC3 variant
 
 
 Example Games:
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 Di 4 Ci - Ji Qi Ren Dai Zhan
 Ji Jia Zhan Shi
 
 
 Notes:
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 This mapper is a modified MMC3 (or is based on MMC3?).
 
 In addition to any CHR-ROM present, there is also an additional 2k of CHR-RAM which is selectable.  CHR pages
 $08 and $09 select CHR-RAM, other pages select CHR-ROM
 
 Apart from that, this mapper behaves exactly like your typical MMC3.  See mapper 004 for details.