MMC2 pinout

MMC2 Chip: (40/42 pin shrink-DIP)

Modern revisions of the chip are labelled MMC2-L and are 42 pin instead of 40 pin.

                                  .----\/----.
                           GND  - |XX      XX| -  +5V
                        M2 (n) -> |01      40| -  +5V
                   CPU A14 (n) -> |02      39| -  GND
                   CPU A13 (n) -> |03      38| -> CIRAM A10 (n)
                   PRG A15 (r) <- |04      37| -> CHR A15 (r)
                   PRG A14 (r) <- |05      36| -> CHR A12 (r)
                   CPU A12 (s) -> |06      35| -> CHR A14 (r)
                   PRG A13 (r) <- |07      34| <- PPU A12 (n)
                   PRG A16 (r) <- |08      33| -> CHR A13 (r)
                   PRG /CE (r) <- |09      32| -> CHR A16 (r)
                    CPU D4 (s) -> |10      31| <- PPU A8 (s)
                    CPU D3 (s) -> |11      30| <- PPU A5 (s)
                    CPU D0 (s) -> |12      29| <- PPU A9 (s)
                    CPU D1 (s) -> |13      28| <- PPU A4 (s)
                    CPU D2 (s) -> |14      27| <- PPU A11 (s)
                   CPU R/W (n) -> |15      26| <- PPU A3 (s)
                   /ROMSEL (n) -> |16      25| <- PPU A7 (s)
                   PPU /RD (s) -> |17      24| <- PPU A2 (s)
                    PPU A0 (s) -> |18      23| <- PPU A10 (s)
                    PPU A6 (s) -> |19      22| <- PPU A1 (s)
                           GND  - |20      21| <- PPU A13 (s)
                                  `----------'

(r) - this pin connects to the ROM chips only
(n) - this pin connects to the NES connector only
(s) - this pin is shared with the NES connector and ROM chips
(w) - this pin connects to the WRAM only