INES Mapper 088: Difference between revisions

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m (Add cat:MMC3-like)
(reduce mapper088 docs to a reference to mapper206 and hopefully concise description of the wiring difference.)
Line 1: Line 1:
[[Category:iNES Mappers]][[Category:MMC3-like mappers]]
[[Category:iNES Mappers]][[Category:MMC3-like mappers]]
  Here are Disch's original notes: 
 
  ========================
  =  Mapper 088          =
  ========================
 
 
   Example Games:
   Example Games:
   --------------------------
   --------------------------
Line 12: Line 7:
   Dragon Spirit - Aratanaru Densetsu
   Dragon Spirit - Aratanaru Densetsu
    
    
 
This is the same as [[INES Mapper 206|Mapper206]] with the following exception:
  Registers:
* 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.
  Range,Mask:  $8000-FFFF, $8001
 
 
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.
 
    $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} |
      +-------+-------+-------+-------+

Revision as of 22:35, 15 July 2012


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

This is the same as 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.

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.

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