INES Mapper 088: Difference between revisions

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[[Category:iNES Mappers]][[Category:MMC3-like mappers]]
[[Category:iNES Mappers|088]][[Category:MMC3-like mappers|088]][[Category:in NesCartDB|088]]
  Here are Disch's original notes:
[[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.
  =  Mapper 088         =
 
  ========================
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.
  Example Games:
 
  --------------------------
If the CHR ROM is 64K or smaller, it is identical to mapper 206.
  Quinty (J)
 
  Namcot Mahjong 3
There are three games known to use this mapper:
  Dragon Spirit - Aratanaru Densetsu
* [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]
  Registers:
  ---------------------------
 
  Range,Mask:  $8000-FFFF, $8001
 
 
    $8000:  [.... .AAA] Address for use with $8001
 
 
    $8001:  [DDDD DDDD]
      Data port:
        R:0 ->  CHR reg 0
        R:1 ->  CHR reg 1
        R:2 ->  CHR reg 2
        R:3 ->  CHR reg 3
        R:4 ->  CHR reg 4
        R:5 ->  CHR reg 5
        R:6 ->  PRG reg 0
        R:7 ->  PRG reg 1
 
 
  CHR Setup:
  ---------------------------
 
  CHR is split into two halves. $0xxx can only have CHR from the first 64k, $1xxx can only have CHR from the
  second 64k.
 
 
 
        $0000  $0400  $0800  $0C00  $1000  $1400  $1800  $1C00
      +---------------+---------------+-------+-------+-------+-------+
      |    <R:0>    |    <R:1>    |  R:2 |  R:3 |  R:4 |  R:5 |
      +---------------+---------------+-------+-------+-------+-------+
      |                              |                              |
      |  AND written values with $3F  |  OR written values with $40  |
 
 
  PRG Setup:
  ---------------------------
 
        $8000  $A000  $C000  $E000 
      +-------+-------+-------+-------+
      |  R:6  |  R:7  | { -2} | { -1} |
      +-------+-------+-------+-------+

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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