Want to hook up a Wii Nunchuck to an Arduino but don’t want to cut up the cord on your Nunchuck? Yeah me too. So I made some of these:
It’s a small PCB that adapts the Wii Nunchuck connector to standard 4-pin header. I call it the “wiichuck adapter”. It plugs directly into the Arduino, no wiring necessary. You can get one too for $4.
Available from the following wonderful shops:
– FunGizmos.com. FREE DOMESTIC SHIPPING. International shipping for $1 more.
– Little Bird Electronics (Australia)
– SparkFun. Ships domestic & internationally. Be sure to order header pins too!
– and just about any SparkFun distributor
This is a BlinkM:
BlinkMs are “smart LEDs”, a type of smart interface component. A BlinkM consists of an ultrabirght RGB LED backed with a microcontroller with built-in knowledge about 24-bit color spaces, color fading, and color pattern generation. All in a package 0.6” wide. You talk to it over I2C, a serial protocol spoken by many different things. (Arduino speaks it, as do Basic Stamps, and your PC) And you can have over 100 BlinkMs on the same serial bus, each individually addressable. Here’s how they can hook up to an Arduino:
BlinkMs are available from SparkFun (US) and Little Bird Electronics (AU). It’s hard to show in just static pictures how fun and easy it is to play with BlinkMs, so here’s a few quick video guides.
A demonstration of one of the example Arduino sketches “BlinkMTester”, which lets you exercise a BlinkM by typing simple commands to the Arduino.
Exampe Code
There are a couple of examples of how to talk to BlinkMs all zipped up in BlinkM_Examples.zip. You can also peruse them unzipped if you like. The examples are predominately for Arduino currently, but any I2C master will work. Some of the examples so far:
BlinkMCommunicator
A simple serial-to-i2c gateway for PC controlling of BlinkM (for instance via Processing or the BlinkM Sequencer)
BlinkMTester
A general tool to play with a single BlinkM
BlinkMMulti
An example showing how to communicate with multiple BlinkMs
BlinkMScriptWriter
A demonstration of how to write BlinkM light scripts with Arduino
BlinkMChuck
Control the hue & brightness of a BlinkM with a Wii Nunchuck
More examples will be added periodically.
For the Arduino examples, a convenience library called BlinkM_funcs.h has been created. Just drop this .h file into your sketch folder and call the functions to start playing with BlinkM.
The complete list of functions is below, though you’ll probably only use a few of them for a particular project.
Mark Allen of Machine Project is teaching an Arduino course using some of the notes from my Bionic Arduino class. He and his students were seeing in Windows XP & 2000, when trying to getting Processing to talk to Arduino, the cryptic error:
gnu.io.PortInUseException: Unknown Application
at
gnu.io.CommPortIdentifier.open(CommPortIdentifier.java:354)
Both his class and Mark and I separately spent a lot of time trying to figure out what the problem was. Eventually we discovered that it’s because the sketch I had written had a setup() like this:
void setup() {
port = new Serial(this, portname, 19200);
size(400,400);
}
but instead should have been like this:
void setup() {
size(400,400);
port = new Serial(this, portname, 19200);
}
Yes, size() must come before new Serial() on Windows or it will not work. There is a bug report describing a similar problem and is marked RESOLVED, INVALID because as the reference documentation for size() states, “The size() function must be the first line in setup()”.
I’ve been using Processing for a long time and I found this feature of size() surprising. I always figured size() to be just a dimensioning function, not a critical part of sketch startup. I’ve seen many sketches that apparently function correctly where size() is located outside of setup() or is not the first statement in setup(). Perhaps the Processing sketch parser should check the sketch before running it to make sure not statements come before size().
I apologize to any Windows users attempting to use the Processing sketches I wrote for Bionic Arduino. I’ve updated the sketches appropriately so the above issue doesn’t come up.
It will cover many of the same topics covered in my previous Spooky Arduino and Bionic Arduino courses. So if you’re near L.A. and want to have some fun programming computers the size of your finger, sign up now! Machine Project classes usually sell out in a day or so.
The variousprototyping shields available for Arduino are a great, sturdy way to add a breadboard. The Boarduino is another nice way to securely attach an Arduino-like device to a breadboard. But if you already have an Arduino and a solderless breadboard, you can attach the two together with an amazing bit of open source technology called a rubber band.
