NES 2.0 Mapper 432: Difference between revisions

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{{DEFAULTSORT:432}}[[Category:Multicart mappers]][[Category:MMC3-like mappers]][[Category:Mappers with scanline IRQs]]
{{DEFAULTSORT:432}}[[Category:Multicart mappers]][[Category:MMC3-like mappers]][[Category:Mappers with scanline IRQs]]
'''NES 2.0 Mapper 430''' denotes the MMC3-based Realtec '''8090''' multicart circuit board, used for the ''3-in-1 High Standerd [sic] (DP-33)'' multicart.
'''NES 2.0 Mapper 430''' denotes the MMC3-based Realtec '''8090''' multicart circuit board.
* ''3-in-1 High Standerd [sic] (DP-33)''
* ''160000000-in-1'' (unknown cartridge code)


==Outer Bank Register ($6000-$7FFF, write)==
==Solder Pad Enable Register ($6000-$7FFE, even)==
  Mask: $E000
  Mask: $E001
   
   
  D~7654 3210
  D~7654 3210
   ---------
   ---------
   ...B .M.b
   .... ...S
      | | +-- PRG/CHR A17
          +- 1=Replace PRG-ROM with solder pad value
      | +---- 0: PRG/CHR A17=MMC3 PRG/CHR A17 (256 KiB inner PRG/CHR bank)
                in the CPU $8000-$FFFF address range
      |       1: PRG/CHR A17=b (128 KiB inner PRG/CHR bank)
 
      +------- PRG/CHR A18
==Outer Bank Register ($6001-$7FFF, odd)==
Mask: $E001
D~7654 3210
  ---------
  ?NQP CmMb
    ||| |||+- PRG/CHR A17 if M=1
    ||| ||+-- PRG A17 mode
    ||| ||    0: from MMC3 (256 KiB inner bank)
    ||| ||    1: from b (128 KiB inner bank)
    ||| |+--- CHR A17 mode
    ||| |      0: from MMC3 (256 KiB inner bank)
    ||| |      1: from b (128 KiB inner bank)
    ||| +---- CHR A18
    ||+------ PRG A18
    |+------- PRG+CHR A19
    +-------- NROM-128 mode (1=enabled)
 
As it uses the MMC3 clones's WRAM interface, writing to the outer bank register requires enabling and not write-protecting WRAM in the MMC's $A001 register.
As it uses the MMC3 clones's WRAM interface, writing to the outer bank register requires enabling and not write-protecting WRAM in the MMC's $A001 register.
NROM-128 mode forces the MMC3 clone's CPU A14 input low, causing MMC3 register 6 to select both the bank at $8000 and $C000, and register 7 to select both the bank at $A000 and $E000.
==MMC3-compatible registers ($8000-$FFFF)==
==MMC3-compatible registers ($8000-$FFFF)==
Mask: $E001
Mask: $E001


See [[MMC3]].
See [[MMC3]].

Latest revision as of 19:45, 4 August 2022

NES 2.0 Mapper 430 denotes the MMC3-based Realtec 8090 multicart circuit board.

  • 3-in-1 High Standerd [sic] (DP-33)
  • 160000000-in-1 (unknown cartridge code)

Solder Pad Enable Register ($6000-$7FFE, even)

Mask: $E001

D~7654 3210
  ---------
  .... ...S
          +- 1=Replace PRG-ROM with solder pad value
               in the CPU $8000-$FFFF address range

Outer Bank Register ($6001-$7FFF, odd)

Mask: $E001

D~7654 3210
  ---------
  ?NQP CmMb
   ||| |||+- PRG/CHR A17 if M=1
   ||| ||+-- PRG A17 mode
   ||| ||     0: from MMC3 (256 KiB inner bank)
   ||| ||     1: from b (128 KiB inner bank)
   ||| |+--- CHR A17 mode
   ||| |      0: from MMC3 (256 KiB inner bank)
   ||| |      1: from b (128 KiB inner bank)
   ||| +---- CHR A18
   ||+------ PRG A18
   |+------- PRG+CHR A19
   +-------- NROM-128 mode (1=enabled)

As it uses the MMC3 clones's WRAM interface, writing to the outer bank register requires enabling and not write-protecting WRAM in the MMC's $A001 register. NROM-128 mode forces the MMC3 clone's CPU A14 input low, causing MMC3 register 6 to select both the bank at $8000 and $C000, and register 7 to select both the bank at $A000 and $E000.

MMC3-compatible registers ($8000-$FFFF)

Mask: $E001

See MMC3.