Ender, Believe it or not, the pro micro and MMJoy will let you work with the diode either way. You just need to reverse your switch rows and columns if they don't work. I soldered the diode with the stripe towards the board. Ended up with rows and columns switched versus what it was in my mind. Lesson learned. The diode just keeps current from feeding back through the lines and hopefully prevents one switch from firing multiple switches.

Connectors - use the existing cable if you can. This gives you a nice looking, stress relieved cable at the joystick. Who cares if there is a weird looking splice way down the cable. It's under the table right? By re-using the existing cable, you get a pretty and tough cable at the end you're going to be messing with it.


Cut off the original joystick port connector as far away from the joystick as you can get it. This will give you a very long cord. From there, buy a 3 foot standard micro USB cable. Cut the USB cord about a foot from the micro USB connector. Inside the microUSB cable, you'll find four colored wires and sometimes a bare ground wire. Red is 5 volt, black is ground and then white/ green are your USB data lines. You can wire black and ground together if you want. Find conductors in the original cable and match them up - Color1 to black, color2 to red and so on. Whatever colors you choose, just don't cross them. You want to make a straight up splice into the USB cable.


For splices that hold up and are fairly fast, take 2 or 3 zip ties, hold the wires together and zip tie off about 2 inches. From there, solder and heat shrink your individual wire splices. Cover the whole thing with heat shrink again, over the zip ties. I've never had a splice fail using this method.