Planet Arduino

There is a boring part of every computer introduction class that shows how a computer is made up of input, output, and processing. Maybe it wouldn’t be so boring if the input device was a nunchuck. [Brian Lough] thinks so and he belligerently asserts that nunchucks are the best input device ever. With a simple connection to a Wii controller and an associated library, you get access to an analog joystick, two buttons, and an accelerometer.

The nunchuck is meant to plug into a Wii controller and the connection is I²C, so that’s trivial to interface to an Arduino or other small microcontroller. The only issue is making the connection. We might have just snipped the wires, but [Brian] prefers to use a small breakout board that plugs into the stock connector and provides solder points for your own cable. There are options for the breakout boards, and [Brian] has his own design that you can get from OSHPark for about a buck for three boards. You can also just jam wire into the connector, but that’s not always robust.

The controllers use 3.3V which isn’t unusual these days. There’s an available library that makes reading them easy. Obviously, not all applications will be a natural fit, but we did like them on the Tetris game [Brian] created. It is also natural for any kind of motion control like his gimbal mount example.

Even if you don’t have junk Wii controllers hanging around, they are common enough on the resale market and you can buy new third-party controllers without spending much. Makes us sorry we threw away ours in the last move.

If you want to get serious hacking a nunchuck, you can go full custom. Or, just give up, and turn one into a Raspberry Pi.

[Dan], admirably rose to the occasion when his son wanted a new toy. Being a dedicated father — and instead of buying something new — he took the opportunity to abscond to his workbench to convert a Wiimote Nunchuck into a fully wireless controller for his son’s old r/c car — itself, gutted and rebuilt some years earlier.

Unpacking the nunchuck and corralling the I2C wires was simply done. From there, he combined a bit of code, an Arduino pro mini, and two 1K Ohm resistors to make use of an Aurel RTX-MID transceiver that had been lying around. Waste not, want not.

A TI Stellaris Launchpad is the smarts of the car itself, in concordance with a TB6612FNG motor controller. The two Solarbotics GM9 motors with some 3D printed gears give the car some much needed gusto.

In Dan’s own humble words: “nothing out of the ordinary, just a nice example of what one can do with parts mostly gathering dust around any hacker’s house.” If any new parents out there have a spare Wiimote stashed away, you can use the infrared LEDs to make a fairly effective baby monitor.

Just a quick update to let you all know that the code for the Video Game Shield has been updated to support knock-off Nunchucks! What does this mean? Well, for a long time the standard way of interfacing with the Nintendo Wii Nunchucks from an Arduino (using the I2C two-wire protocol) didn’t really work with the cheap knock-off (off-brand) Nunchucks for sale at places like Deal Extreme and Ebay. Fortunately, we recently stumbled upon some updated code that works with all Nunchucks, official as well as knock-off, so we’ve tested it out and updated the Video Game Shield code.

The new code can be found on our download page as well as the Video Game Shield repository at GitHub.

We are shopping around trying to find the best of the cheap knock-off Nunchucks, so look forward to us adding them to the Wayne & Layne store in the near future!