Color Dreams: Difference between revisions

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m (replacing self redirect with bold)
(what was i smoking when i added the oversize section? you should just use oversize gnrom anyway.)
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   I have no idea how this works.  [http://kevtris.org/mappers/lockout/ Kevtris's page makes mention of it].  From an emulation standpoint, it's not all
   I have no idea how this works.  [http://kevtris.org/mappers/lockout/ Kevtris's page makes mention of it].  From an emulation standpoint, it's not all
   that important.
   that important.
== Emulator oversize support ==
FCEUX's implementation:
    $8000-FFFF:  [CCCC PPPP]
Nestopia's implementation:
    $8000-FFFF:  [PPPP PPPP]
                [CCCC ....]
''See also:'' [[Oversize]]


== Sources ==
== Sources ==
*[http://kevtris.org/mappers/cdreams/ Color Dreams doc by Kevin Horton]
*[http://kevtris.org/mappers/cdreams/ Color Dreams doc by Kevin Horton]

Revision as of 21:32, 24 April 2014

Color Dreams was a company that developed and published unlicensed NES games. The later Color Dreams games were Christianity-themed games, published under the Wisdom Tree label and sold through Christian bookstores.

Color Dreams games used a board with a discrete logic mapper that provide up to four 32 KB banks of PRG ROM and up to sixteen 8 KB banks of CHR ROM and controls a charge pump to defeat the CIC lockout chip. The iNES format assigns mapper 11 to these boards.

Overview

  • PRG ROM size: Up to 128 KB
  • PRG ROM bank size: 32 KB
  • PRG RAM: None
  • CHR capacity: Up to 128 KB ROM
  • CHR bank size: 8 KB
  • Nametable mirroring: Solder pads select vertical or horizontal mirroring
  • Subject to bus conflicts: Yes

Banks

  • CPU $8000-$FFFF: 32 KB switchable PRG ROM bank
  • PPU $0000-$1FFF: 8 KB switchable CHR ROM bank

Registers

Bank select ($8000-$FFFF)

7  bit  0
---- ----
CCCC LLPP
|||| ||||
|||| ||++- Select 32 KB PRG ROM bank for CPU $8000-$FFFF
|||| ++--- Used for lockout defeat
++++------ Select 8 KB CHR ROM bank for PPU $0000-$1FFF

Hardware

The Color Dreams board contains a 74LS377 octal D latch (8-bit register) to select the current PRG and CHR banks.

Variants

Nintendo's own GxROM family of boards is nearly identical in function to the Color Dreams board.

A multicart mapper based on this mapper is iNES Mapper 046, with an outer bank register at $6000-$7FFF.

Disch's Notes

 Here are Disch's original notes:
 ========================
 =  Mapper 011          =
 ========================
 
 Example Games:
 --------------------------
 Crystal Mines
 Metal Fighter
 
 Notes:
 --------------------------
 This mapper suffers from bus conflicts!
 
 
 Registers **BUS CONFLICTS**:
 --------------------------
   $8000-FFFF:  [CCCC LLPP]
     P = Select 32k PRG page @ $8000-FFFF
     L = Lockout defeat usage
     C = Select 8k CHR page @ $0000-1FFF
 
 
 Lockout defeat:
 --------------------------
 I have no idea how this works.  Kevtris's page makes mention of it.  From an emulation standpoint, it's not all
 that important.

Sources