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@ansarid
Last active March 23, 2018 01:02
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#include <Wire.h>
static uint8_t nunchuck_buf[6]; // array to store nunchuck data,
void setup(){
Serial.begin(115200);
nunchuck_setpowerpins(); // use analog pins 2&3 as fake gnd & pwr
nunchuck_init(); // send the initilization handshake
}
void loop(){
nunchuck_get_data();
// map nunchuk data to a servo data point
int x_axis = map(nunchuck_buf[0], 23, 222, 180, 0);
int y_axis = map(nunchuck_buf[1], 32, 231, 0, 180);
nunchuck_print_data();
}
static void nunchuck_setpowerpins(){
#define pwrpin PORTC3
#define gndpin PORTC2
DDRC |= _BV(pwrpin) | _BV(gndpin);
PORTC &= ~ _BV(gndpin);
PORTC |= _BV(pwrpin);
delay(100); // wait for things to stabilize
}
// initialize the I2C system, join the I2C bus,
// and tell the nunchuck we're talking to it
void nunchuck_init(){
Wire.begin(); // join i2c bus as master
Wire.beginTransmission(0x52); // transmit to device 0x52
Wire.write(0x40); // sends memory address
Wire.write(0x00); // sends sent a zero.
Wire.endTransmission(); // stop transmitting
}
// Send a request for data to the nunchuck
// was "send_zero()"
void nunchuck_send_request(){
Wire.beginTransmission(0x52); // transmit to device 0x52
Wire.write(0x00); // sends one byte
Wire.endTransmission(); // stop transmitting
}
// Receive data back from the nunchuck,
int nunchuck_get_data(){
int cnt = 0;
Wire.requestFrom (0x52, 6); // request data from nunchuck
while (Wire.available ()) {
// receive byte as an integer
nunchuck_buf[cnt] = nunchuk_decode_byte(Wire.read());
cnt++;
}
nunchuck_send_request(); // send request for next data payload
// If we recieved the 6 bytes, then go print them
if (cnt >= 5) {
return 1; // success
}
return 0; //failure
}
// Print the input data we have recieved
// accel data is 10 bits long
// so we read 8 bits, then we have to add
// on the last 2 bits. That is why I
// multiply them by 2 * 2
void nunchuck_print_data(){
static int i = 0;
int joy_x_axis = nunchuck_buf[0];
int joy_y_axis = nunchuck_buf[1];
int z_button = 1;
int c_button = 1;
// byte nunchuck_buf[5] contains bits for z and c buttons
// it also contains the least significant bits for the accelerometer data
// so we have to check each bit of byte outbuf[5]
if ((nunchuck_buf[5] >> 0) & 1)
z_button = 0;
if ((nunchuck_buf[5] >> 1) & 1)
c_button = 0;
Serial.print("joy:");
Serial.print(joy_x_axis, DEC);
Serial.print(",");
Serial.print(joy_y_axis, DEC);
Serial.print(" \t");
Serial.print("c:");
Serial.print(c_button, DEC);
Serial.print(" \t");
Serial.print("z:");
Serial.print(z_button, DEC);
Serial.print("\r\n");
i++;
}
// Encode data to format that most wiimote drivers except
// only needed if you use one of the regular wiimote drivers
char nunchuk_decode_byte (char x){
x = (x ^ 0x17) + 0x17;
return x;
}
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