Sunsoft 4 pinout
Sunsoft 4: 40-pin 0.6" PDIP
.---\/---.
M2 -> | 01 40 | -- +5V
/ROMSEL -> | 02 39 | <- R/W
CPU A14 -> | 03 38 | <- CPU D6
CPU A13 -> | 04 37 | <- CPU D5
CPU A12 -> | 05 36 | <- CPU D4
PPU /A13 -> | 06 35 | <- CPU D3
PPU A12 -> | 07 34 | <- CPU D2
PPU A11 -> | 08 33 | <- CPU D1
PPU A10 -> | 09 32 | <- CPU D0
?GND -> | 10 31 | <- OR A (PPU /RD)
PRG /CE <- | 11 30 | <- OR B (SS4 /CHRSEL)
CHR A17 <- | 12 29 | -> OR Y (CHR /CS)
CHR A16 <- | 13 28 | -> CIRAM /CS
CHR A15 <- | 14 27 | -> SS4 /CHRSEL
CHR A14 <- | 15 26 | -> WRAM /CE
CHR A13 <- | 16 25 | -> PRG A14
CHR A12 <- | 17 24 | -> PRG A15
CHR A11 <- | 18 23 | -> PRG A16
CHR A10 <- | 19 22 | -> PRG A17
GND -- | 20 21 | -> WRAM +CE
`--------'
10 probably actually some control, not a supply pin
19 also connects to CIRAM A10
29,30,31 actually just an OR gate; for use with a 28-pin 128KB CHR-ROM
Reference: Naruko’s notes
“NEC 65006-389” is legible on the die, indicating that this is a µPD65006 NEC CMOS-4A 1.5µ gate array with 504 pairs of 2P+2N MOSFETs.
Tengen’s Sunsoft-4 seems to have a little modified pinout: [1]
.. |
31 | <- OR A (PPU /RD)
30 | <- OR B (PPU A13)
29 | -> (NC?)
28 | -> CIRAM /CS
27 | -> (NC?)
26 | -> goes to NOR gate CHR roms decoder
.. |