Notes

• You can only use true switch-based joysticks with this circuit.
• PPJoy, unlike Linux, will not allow you to use this interface on the same parallel port as another interface type.
• The pull-up resistors are 10k Ohm.
• The original diagram only specifies "Power"; we source it from Pin 1 (nStrobe). PPJoy drives pin 1, 14, 16 and 17 high; any one of these can be used as power source.
• General notes about interface construction

Credits