The following schematic shows the PlayStation 2 Controller Cable Connector Pinout Diagram. Here is the description (click image to enlarge):
- Pin 1 for Data/Signal transfer from Controller to PSX, this signal is an 8 bit serial transmission synchronous to the falling edge of clock.
- Pin 2, Command, is the counter part of DATA. It is again an 8 bit serial transmission on the falling edge of clock.
- Pin 3 is unused.
- Pin 4 for Ground.
- Pin 5, VCC, this can vary from 5V down to 3V and the official SONY Controllers will still operate.
- Pin 6, is used to get the attention of the controller, this signal will go low for the duration of a transmission.
- Pin 7, Clock, is used to keep units in sync.
- Pin 8, is not connected or N/C.
- Pin 9, ACK, is acknowledge signal from Controller to PSX.