I hacked an N64 controller, so the player has to scream instead of pressing 'B'.

What?

I used a relay and microphone to hijack the Nintendo controller's 'B' button. If a player wants to press 'B' they need to make noise loud enough to trigger the relay.

NO ARDUINO OR PROGRAMMING REQUIRED just super janky electronics.

Why?

Arin Hanson of GameGrumps invited us to visit their office, and it's not proper to show up empty handed.

As for where 'scream sensor' came from, I've got this box of 'Arduino sensor modules' and we dug through it imagining how you'd play old N64 games with inputs other than buttons.

Video

Filming by cameramanjohn

 Instructions

There are much better ways to do this, but here are modules similar to what I used:

• Relay Module
• Microphone Module
• Resistor somewhere around 100-220 ohms (I tried to mimic the button circuit)

Connect 5v and groud to both modules, then the digital pin of the microphone (labeled 'D0' I think) to the relay module input (labeled 'S' I think).

Pull the controller PCB out.

N64 controller PCB

I back-traced the button pad and found two exposed pads to solder to.

Solder points

Each of those solder points touches one half of the 'B' button. Normally that circuit is completed when the button bridges the weird squiggly black traces next to the hack wires.

Solder points, better angle

I'm not sure how important the resistor is, but I measured the resistance between the two hack wires when pressing the 'B' button down and it was somewhere between 100-200ohms. The relay is basically a short, so I added a 220ohm resistor in line just to be safe. It doesn't matter which wire you put the resistor on.

Then connect the two hack wires to the 'normally-open' screw terminals of the relay module. When the microphone signal peaks, the relay turns on and the N64 thinks the 'B' button was pressed.

All that's left to do is adjust the potentiometer on the microphone module.

Microphone module

Adjust the little brass screw until the relay clicks on or off. Adjust it a little more so that the relay is off, but turns on when you scream into the mic. Try blowing into the mic if you don't want to yell, that's an easy way to generate a large signal.

Conclusion

This project was pretty easy, but is relatively invasive for the N64 controller. There's some Arduino code online that lets you read the controller commands so you could probably intercept the commands, modify them, and send them to the console without ever disassembling the controller.

A relay is totally overkill for this project, but they're cheap and more importantly all I had at the time. An optoisolator might be a better choice..

The End

For now... I have plans to modify another controller with different sensors.