Namcot 108 family pinout
Namcot 108, 109, 118, 119: 28-pin shrink PDIP, also Tengen 337001 or MIMIC-1: 28-pin 0.6" PDIP (Canonically mapper 206).
.--\/--. (f) CPU A14 -> |01 28| -> PRG A15 (r) (fr) CPU A0 -> |02 27| -> PRG A14 (r) (fr) CPU D5 -> |03 26| <- M2 (f) (fr) CPU D0 -> |04 25| -> PRG A13 (r) (fr) CPU D4 -> |05 24| <- CPU A13 (f) (fr) CPU D1 -> |06 23| -> PRG A16 (r) Gnd -- |07 22| -> PRG /CE (r) (fr) CPU D3 -> |08 21| -- +5V (fr) CPU D2 -> |09 20| -> CHR A13 (r) (f) /ROMSEL*-> |10 19| -> CHR A11 (r) (f) R/W -> |11 18| -> CHR A10 (r) (r) CHR A15 <- |12 17| <- PPU A10 (f) (r) CHR A14 <- |13 16| <- PPU A11 (f) (r) CHR A12 <- |14 15| <- PPU A12 (f) `------' 10: on the Vs. System daughterboards, this is instead CPU /A15
No behavioral differences are known between the five different part numbers; several games were released on the same board with identical code and different mapper ICs.
Functional Variations
Many boards (and thus iNES mappers) redefined parts of the pinout for various extensions, mostly to increase the amount of addressable CHR ROM.
3446
Mapper 76: Rewires CHR banking to be able to address more total CHR with coarser CHR banks.
(fr) CPU D2 -> |09 20| -> CHR A14 (r) (f) /ROMSEL -> |10 19| -> CHR A12 (r) (f) R/W -> |11 18| -> CHR A11 (r) (r) CHR A16 <- |12 17| <- PPU A11 (f) (r) CHR A15 <- |13 16| <- PPU A12 (f) (r) CHR A13 <- |14 15| <- +5V `------' (f) PPU A10 -> CHR A10 (r)
3433, 3443, 3453
Mappers 88 and 154 connect (f) PPU A12 -> CHR A16 (r), skipping the mapper IC altogether.
3425
Mapper 95: Repurposes CHR A15 to control nametable banking
(f) CIRAM A10 <- |12 17| <- PPU A10 (f) (r) CHR A14 <- |13 16| <- PPU A11 (f) (r) CHR A12 <- |14 15| <- PPU A12 (f) `------'
Pirate clones
AX-24G or NTDEC8701: 28-pin 0.6" PDIP
.--\/--. .--\/--. (r) PRG A13 <- |01 28| <- CPU A14 (f) M2 -> |01 28| -- +5V (r) PRG A14 <- |02 27| <- CPU A13 (f) CPU R/!W -> |02 27| <- RESET (r) PRG A16 <- |03 26| <- CPU A0 (fr) MODE/CPU A14 -> |03 26| <- CPU D3 (r) PRG A15 <- |04 25| -- VCC CPU A13 -> |04 25| -> CHR A15 (r) CHR A14 <- |05 24| <- /ROMSEL (f) CPU D1 -> |05 24| -> CHR A14 (r) CHR A11 <- |06 23| -> PRG /OE (r) CPU D0 -> |06 23| -> CHR A13 (r) CHR A13 <- |07 22| <- M2 (f) CPU !RMS -> |07 22| -> CHR A12 (r) CHR A12 <- |08 21| <- R/W (f) CPU D4 -> |08 21| -> CHR A11 (fr) CPU D2 -> |09 20| <- CPU-D0 (fr) CPU A0 -> |09 20| -> CHR A10 (fr) CPU D3 -> |10 19| <- CPU-D5 (fr) PRG A16 <- |10 19| <- CPU D5 (fr) CPU D1 -> |11 18| <- CPU-D4 (fr) PRG A15 <- |11 18| <- PPU A12 Gnd -- |12 17| <- PPU-A12 (f) PRG A14 <- |12 17| <- PPU A11 (r) CHR A15 <- |13 16| <- PPU-A11 (f) PRG A13 <- |13 16| <- PPU A10 (r) CHR A10 <- |14 15| <- PPU-A10 (f) GND -- |14 15| <- CPU D2 `------' `------' AX-24G or NTDEC8701 KS 204
KS204 MODE: If pin 3 is low on a falling edge of RESET, it operates in N108 mode. If it's high, or before the first falling edge of RESET, it operates in VRC2 mode. [1]
Functional variations
KS7037
Mapper 307 (UNIF "KS7037"): repurpose CHR banking for nametable control. Moves second switchable bank.
.--\/--. M2 -> |01 28| -- +5V R/W -> |02 27| <- RESET CPU A13 -> |03 26| <- CPU D3 CPU A14 -> |04 25| -> n/c CPU D1 -> |05 24| -> n/c CPU D0 -> |06 23| -> n/c /ROMSEL -> |07 22| -> n/c CPU D4 -> |08 21| -> n/c CPU A0 -> |09 20| -> CIRAM A10 PRG A16* <- |10 19| <- CPU D5 PRG A15 <- |11 18| <- +5V PRG A14 <- |12 17| <- PPU A11 PRG A13 <- |13 16| <- PPU A10 GND -- |14 15| <- CPU D2 `------' KS 204
External hardware further modifies the exact memory map.
Sachen 3009
Redundant variation of mapper 133: obfuscatory GNROM-style banking.
.--\/--. n/c <- |01 28| <- CPU A14 (f) n/c <- |02 27| <- CPU A13 (f) n/c <- |03 26| <- CPU A0 (fr) n/c <- |04 25| -- VCC feedback#1 <- |05 24| <- /ROMSEL (f) (r) PRG A15 <- |06 23| -> PRG /OE (r) (r) CHR A14 <- |07 22| <- M2 (f) (r) CHR A13 <- |08 21| <- R/W (f) (fr) CPU D0 -> |09 20| <- CPU D3 (fr) (fr) CPU D1 -> |10 19| <- CPU D4 (fr) (fr) CPU D2 -> |11 18| <- CPU D5 (fr) Gnd -- |12 17| <- Vcc feedback#2 <- |13 16| <- feedback#2 n/c <- |14 15| <- feedback#1 `------' AX-24G