Next we’ll solder the other ribbon cable. Now we’ll solder all the wires to the Teensy, starting with the first ribbon, to do this you’ll need a vise or helping hands to hold the Teensy while you do the soldering. You can do this by cutting it or pulling each wire off after heating it with a soldering iron.
Cut around 12cm of ribbon cable, split the ends and strip them.Carefully take out the PCB, noting how all the buttons parts are fitted.Take off the screws that hold the case together.You should be able to use these instructions as a guide for any SNES gamepad. There are many variants of the SNES gamepad so the images here might not exactly match your controller physically. You can then map this to the controls of any game. Each button will output a different letter. The gamepad will be recognised as a keyboard by your computer.
This project shows you how to convert a SNES gamepad to USB controller.