VRC1 pinout

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There isn't a consistent pinout for the VRC1 and its clones; here are two. The pins are mostly in the same order, but power and ground definitely move.

Anything with a ? next to it is uncertain; these pinouts were deduced solely based on images of the PCB.

VRC-1: 28-pin 0.6" DIP (canonically mapper 75)

Labeled "Konami 8626K7 007422 VRC 075" on PCB labeled "Konami 302114A":

                .--\/--.
 (r) PRG A15 <- |01  28| -- +5V
 (r) PRG A14 <- |02  27| <- CPU A14 (f)
(fr) CPU A12 -> |03  26| <- CPU A13 (f)
 (r) PRG A13 <- |04  25| <- PPU A12 (f)
 (r) PRG A16 <- |05  24| <- PPU A11 (fr)
 (fr) CPU D0 -> |06  23| <- PPU A10 (fr)
 (fr) CPU D1 -> |07  22| -> PRG nSEL (r)
 (fr) CPU D2 -> |08  21| <- CPU R/W (f)
 (fr) CPU D3 -> |09  20| -> CHR nSEL (r)
 (r) CHR A12 <- |10  19| <- PPU A13 (f)
 (r) CHR A14 <- |11  18| <- PPU nRD (f)
 (r) CHR A13 <- |12  17| -> CIRAM A10?
 (r) CHR A15 <- |13  16| <- CPU nROMSEL (f)
         Gnd -- |14  15| -> CHR A16 (r)
                `------'

Labeled "VRC 007421 8805 Z04" on PCB labeled "JALECO-20":

               .--\/--.
(r) PRG A15 <- |01  28| <- CPU A14 (f)
   ?PRG A14 <- |02  27| <- CPU A13 (f)
   ?CPU A12 -> |03  26| <- CPU nROMSEL? 
   ?PRG A13 <- |04  25| <- PPU A12?		 
(r) PRG A16 <- |05  24| <- PPU A11?		 
(fr) CPU D0 -> |06  23| <- CPU RnW (f)
        Gnd -- |07  22| -> PRG nSEL (r)
(fr) CPU D1 -> |08  21| -- +5V
(fr) CPU D2 -> |09  20| -> CHR nSEL?
(fr) CPU D3 -> |10  19| <- PPU A10?
   ?CHR A12 <- |11  18| <- PPU nRD (f)
(r) CHR A14 <- |12  17| -> CIRAM A10 (f)
   ?CHR A13 <- |13  16| <- (CPU nROMSEL OR CPU RnW)?
(r) CHR A15 <- |14  15| -> CHR A16 (r)
               `------'