Make Your Own NES Style ColecoVision Controller

After fiddling with a broken ColecoVision "Hand Controller" I saw how simple the wiring was and decided to see if I could re-purpose a cheap aftermarket NES Classic controller to make a more comfortable control option for my ColecoVision.  It actually worked pretty easily so I decided to turn my scribbled diagrams into something that might be easier for others to use.

Just a disclaimer, this diagram and instructions are provided freely and without warranty.  It's not my fault if you damage anything by following these diagrams/instructions.

The original ColecoVision hand controller uses diodes between all of the connections to make it possible to register multiple button presses.  Because the direction buttons each have a dedicated address line this isn't so important for them, however without using diodes it will not be possible to register simultaneous presses of the other buttons.    I tried incorporating the same IN14148 diodes into my controller mod, but I could never get the thing to work properly until I removed them and just made direct connections. 

If you follow the diagram the way I have it depicted the NES-style pad will have the "Start" button mapped to "1".  All of the games I have require this in order to start so that seemed appropriate.  Evidently some games (which I don't have) require "*" to start, so that is mapped to "Select" on the NES-style gamepad.

I used a very cheap aftermarket NES Classic controller for this.  Please don't use a genuine NES controller for this, or at least not the PCB from one as I would hate to think of a genuine piece of classic gaming hardware being damaged to make one of these.

Materials:

• Cheap aftermarket NES-style control pad (like this for example or this)
• A DE9 Controller cable (like this). You could salvage a cable from an old aftermarket controller, but keep in mind not all controllers that use this connector use all its pins.  It needs to have at least pins 1, 2, 3, 4, 5, 6, and 8 populated in order to work for this.
• 30-gauge wrapping wire
• Soldering Iron
• Razor or Craft Knife
• Multi-meter with continuity check feature

Process:

1. Disassemble the control pad

2. Disconnect or de-solder the existing cable

3.  If your new DE9 cable came with strain relief on the controller end, you'll need to remove it, then cut open the outer cable and strip the ends of the 9 wires inside.  Give yourself about 3 inches of length to work with.

4. Use your multi-meter continuity test to figure out which pin each wire is connected to and write down the color and pin-number using the diagram below. 

5. Pre-tin the wires.  You don't need to pre-tin the wires connected to pins 7 or 9 as they are not used.

6. Locate the common/ground circuit.   One of the wires from the original cable was connected to one side of every one of the button pads on the controller - that's your common wire.  Also note which side of each button pad is connected to the common wire - in the diagram below the left side of each button pad is shown connected to the common wire, but this won't necessarily be the case with the PCB from your game pad.

4. Solder the wire from pin 8 of the DE9 plug to the common/ground part of the circuit.  In my case I just used the solder point from the control pad's original cable.

5. Solder the wire from Pin 1 to the non-common side of the Up button.

6. Solder the wire from Pin 2 to the non-common side of the Down button.

7. Solder the wire from Pin 3 to the non-common side of the Left button.

8. Solder the wire from Pin 4 to the non-common side of the Right button.

9. Solder the wire from Pin 6 to the non-common side of the A button.

10. Use a razor or X-acto knife to sever the connection between the B button and the common wire. Use your multi-meter's continuity function to verify they are no longer connected.

11. Solder a small length of wrapping wire between the non-common side of the A button and the non-common side of the B button (shown in yellow in the diagram).

12. Solder the wire from Pin 5 to the common-side of the B button (which is no longer attached to the common wire).

13. Use a razor or X-acto knife to sever the connection between the Start button and the common wire. Verify with your meter.

14. Solder a small length of wrapping wire between the common side of the B button and the non-common side of the Start button.

15. Solder a small length of wrapping wire between the (disconnected) common side of the Start button and the non-common side of the Right button. (shown in yellow in the diagram)

16. Use a razor or X-acto knife to sever the connection between the Select button and the common wire.  Verify with your meter.

17. Solder a small length of wrapping wire between the non-common side of the Start button and the non-common side of the Select button.

18. Solder a small length of wrapping wire between the (disconnected) common side of the Select button and the non-common side of the Right button.

19. Solder a small length of wrapping wire between the (disconnected) common side of the Select button and the non-common side of the Down button.

20. Double-check all of the connections with your meter, give the wires a gentle tug to make sure nothing has come loose or has a cold solder joint.

21. Assemble and test.