NES 2.0 Mapper 432
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
- Submapper 4: 940702 PCB
Mask: $E001
D~7654 3210
---------
.... ...S
+- 1=Replace PRG-ROM with solder pad value
in the CPU $8000-$FFFF address range
- Submapper 1 selects the solder pad via 6001.5 instead, and this register has no function.
- Submapper 4 just disables PRG-ROM when S=1 and the solder pad is connected.
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.
Mask: $E001
See MMC3.