INES Mapper 088

iNES Mapper 088 is the same as mapper 206 with the following exception:

• CHR support is increased to 128KB by connecting PPU's A12 line to the CHR ROM's A16 line.

Consequently, CHR is split into two halves. $0xxx can only have CHR from the first 64K, $1xxx can only have CHR from the second 64K.

A possible way to implement this would be to mask the CHR ROM 1K bank output from the mapper by ANDing with $3F, and then OR it with $40 if the PPU address was >= $1000.

 Example Games:
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 Quinty (J)
 Namcot Mahjong 3
 Dragon Spirit - Aratanaru Densetsu