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.)
m (Updated deprecated bootgod links to redirect to their NESCartDB equivalents.)
 
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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.


  Example Games:
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.
  --------------------------
 
  Quinty (J)
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 for N108 registers 2, 3, 4, and 5.
  Namcot Mahjong 3
  Dragon Spirit - Aratanaru Densetsu
 
This is the same as [[INES Mapper 206|Mapper206]] with the following exception:
* CHR support is increased to 128KB by connecting PPU's A12 line to the CHR ROM's A16 line.


For example, mask the CHR ROM 1K bank output from the mapper by $3F, and then OR it with $40 if the PPU address was >= $1000.
If the CHR ROM is 64K or smaller, it is identical to mapper 206.


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.
There are three games known to use this mapper:
* [https://nescartdb.com/profile/view/1576/quinty Quinty (J)]
* [https://nescartdb.com/profile/view/1828/namco-mahjong-iii-mahjong-tengoku Namcot Mahjong 3 - Mahjong Tengoku]
* [https://nescartdb.com/profile/view/2307/dragon-spirit-aratanaru-densetsu Dragon Spirit - Aratanaru Densetsu]

Latest revision as of 01:33, 14 September 2023

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 for N108 registers 2, 3, 4, and 5.

If the CHR ROM is 64K or smaller, it is identical to mapper 206.

There are three games known to use this mapper:

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