Wiichuck Adaptor

One of the coolest things about the Wii (to me) is that the expansion port on the bottom of the Wii remote is an I2C serial connection. This means that anything that plugs into that port can work with microcontrollers like the Arduino or Basic Stamp or others. Of the available peripherals, the Wii Nunchuck is one of the best. It contains a 3-axis accelerometer, a 2-axis joystick, and two buttons. Hooking up a Wii Nunchuck to Arduino is easy and I have class notes describing how to do it. But cutting off the connector of the Nunchuck to get at the wires is a little drastic.

This is what it looks like with Arduino plugged into the Nunchuck.

This “wiichuck adapter” let’s you play with the Wii Nunchuck and other Wii remote peripherals without needing you to cut cables. Just plug it into the Wii Nunchuck, then into the Arduino, in to Analog In pins 2,3,4,5. Pins 4&5 are the I2C communication pins and Pins 2&3 can act as the power supply for the Nunchuck.

WiichuckDemo.pde Arduino Code

/*
 * WiiChuckDemo -- 
 *
 * 2008 Tod E. Kurt, http://thingm.com/
 *
 */

#include <Wire.h>
#include "nunchuck_funcs.h"

int loop_cnt=0;

byte accx,accy,zbut,cbut;
int ledPin = 13;


void setup()
{
    Serial.begin(19200);
    nunchuck_setpowerpins();
    nunchuck_init(); // send the initilization handshake
    
    Serial.print("WiiChuckDemo ready\n");
}

void loop()
{
    if( loop_cnt > 100 ) { // every 100 msecs get new data
        loop_cnt = 0;

        nunchuck_get_data();

        accx  = nunchuck_accelx(); // ranges from approx 70 - 182
        accy  = nunchuck_accely(); // ranges from approx 65 - 173
        zbut = nunchuck_zbutton();
        cbut = nunchuck_cbutton(); 
            
        Serial.print("accx: "); Serial.print((byte)accx,DEC);
        Serial.print("\taccy: "); Serial.print((byte)accy,DEC);
        Serial.print("\tzbut: "); Serial.print((byte)zbut,DEC);
        Serial.print("\tcbut: "); Serial.println((byte)cbut,DEC);
    }
    loop_cnt++;
    delay(1);
}