INES Mapper 088: Difference between revisions
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(reduce mapper088 docs to a reference to mapper206 and hopefully concise description of the wiring difference.) |
(refile, add cat:nescartdb, also reorder the entire page to put a standard "this mapper exists because X" at the beginning) |
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[[Category:iNES Mappers]][[Category:MMC3-like mappers]] | [[Category:iNES Mappers|088]][[Category:MMC3-like mappers|088]][[Category:in NesCartDB|088]] | ||
[[iNES Mapper 088]] is the same as [[INES Mapper 206|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: | Example Games: | ||
Line 6: | Line 12: | ||
Namcot Mahjong 3 | Namcot Mahjong 3 | ||
Dragon Spirit - Aratanaru Densetsu | Dragon Spirit - Aratanaru Densetsu | ||
Revision as of 20:24, 2 August 2012
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: -------------------------- Quinty (J) Namcot Mahjong 3 Dragon Spirit - Aratanaru Densetsu