NES 2.0 Mapper 432: Difference between revisions

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(Created page with "'''NES 2.0 Mapper 432''' denotes the '''Realtec 8090''' PCB, used for the MMC3-based ''3-in-1 High Standerd [sic] (DP-33)'' multicart.")
 
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'''NES 2.0 Mapper 432''' denotes the '''Realtec 8090''' PCB, used for the [[MMC3]]-based ''3-in-1 High Standerd [sic] (DP-33)'' multicart.
{{DEFAULTSORT:432}}[[Category:Multicart mappers]][[Category:MMC3-like mappers]][[Category:Mappers with scanline IRQs]][[Category:NES 2.0 mappers with submappers]]
'''NES 2.0 Mapper 432''' denotes a series of MMC3-based Realtec multicart circuit boards.
* Submapper 0: Realtec 8043, 8086, 8090, GN-30C PCB
* Submapper 1: Realtec 8023 PCB
* Submapper 2: Realtec 8085 PCB
* Submapper 3: Realtec 8145 PCB
 
==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
  ---------
  pNQP 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
  ||+------- Submapper-specific functionality
  ||        Submapper 0: PRG+CHR A19
  ||        Submapper 1: Read solder pad
  ||        Submapper 2: NROM-256 mode
  ||        Submapper 3: 512 KiB MMC3 CHR mode (like [[INES Mapper 197]] Submapper 2)
  |+-------- NROM-128 mode (1=enabled)
  +--------- Submapper 0/1: NROM-256 mode
              Submapper 2/3: Lock Outer Bank 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)==
Mask: $E001
 
See [[MMC3]].

Latest revision as of 10:49, 22 February 2025

NES 2.0 Mapper 432 denotes a series of MMC3-based Realtec multicart circuit boards.

  • Submapper 0: Realtec 8043, 8086, 8090, GN-30C PCB
  • Submapper 1: Realtec 8023 PCB
  • Submapper 2: Realtec 8085 PCB
  • Submapper 3: Realtec 8145 PCB

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
  ---------
  pNQP 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
  ||+------- Submapper-specific functionality
  ||         Submapper 0: PRG+CHR A19
  ||         Submapper 1: Read solder pad
  ||         Submapper 2: NROM-256 mode
  ||         Submapper 3: 512 KiB MMC3 CHR mode (like INES Mapper 197 Submapper 2)
  |+-------- NROM-128 mode (1=enabled)
  +--------- Submapper 0/1: NROM-256 mode
             Submapper 2/3: Lock Outer Bank 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)

Mask: $E001

See MMC3.