WRAM pinout

Pinout
____________________              |                    |        +5V -- | 01. 64 | -- GND CPU D4 <> | 02             63 | <> CPU D3     CPU D5 <> | 03              62 | <> CPU D2     CPU D6 <> | 04              61 | <> CPU D1     CPU D7 <> | 05              60 | <> CPU D0 SYSTEM CLK -> | 06              59 | <- CPU /WR REFRESH -> | 07             58 | <- /PWR /RESET -> | 08             57 | <- CPU /RD NC -- | 09             56 | <- /PRD CS1 -> | 10             55 | ?? G       CS2 -> | 11              54 | <- PA1 CS3 -> | 12             53 | <- PA0 /CS1 (GND) -> | 13             52 | <- PS3 (PA7) /CS2 (GND) -> | 14             51 | <- PS2 (+5V) /CS3 -> | 15  Nintendo   50 | <- PS1 (+5V)                    Orientation: +5V -- | 16   S-WRAM    49 | -- +5V GND -- | 17             48 | -- GND                       64         33 NC -- | 18             47 | <- /PS5                       |         | NC -- | 19             46 | <- /PS4                      .---. NC -- | 20             45 | <- /PS3                      | Nintendo  | NC -- | 21             44 | <- /PS2                      |  S-WRAM  O|         NC -- | 22              43 | <- /PS1                      |. |    CPU A0 -> | 23              42 | <- ENABLE                    '---' CPU A9 -> | 24             41 | <- CPU A8                     |         | CPU A1 -> | 25             40 | <- CPU A16                   01         32 CPU A10 -> | 26             39 | <- CPU A7     CPU A2 -> | 27              38 | <- CPU A15               Legend: CPU A11 -> | 28             37 | <- CPU A6                     CPU A3 -> | 29              36 | <- CPU A14               --[S-WRAM]-- Power, n/a CPU A12 -> | 30     O       35 | <- CPU A5                ->[S-WRAM]<- S-WRAM input CPU A4 -> | 31             34 | <- CPU A13               <-[S-WRAM]-> S-WRAM output +5V -- | 32             33 | -- GND                   <>[S-WRAM]<> Bidirectional |____________________|                         ??[S-WRAM]?? Unknown

Signal descriptions

 * PS3, /PS5..1: These are peripheral bus enables and are connected to PA7..2 to map S-WRAM to $80-83.