3-Axis GYRO.ino

/*
    3-Axis GYRO
   
 Sample codes functions 
 for Gyroscope ITG3205.
 
 Codes by;
 e-Gizmo Mechatronix Central
 http://www.e-gizmo.com
 
from http://www.varesano.net//

*/

#include <Wire.h> // I2C library, gyroscope
// Gyroscope ITG3200 
#define GYRO 0x68 //  when AD0 is connected to GND ,gyro address is 0x68.
//#define GYRO 0x69   when AD0 is connected to VCC ,gyro address is 0x69  
#define G_SMPLRT_DIV 0x15
#define G_DLPF_FS 0x16
#define G_INT_CFG 0x17
#define G_PWR_MGM 0x3E
#define G_TO_READ 8 // 2 bytes for each axis x, y, z
// offsets are chip specific. 
int g_offx = 120;
int g_offy = 20;
int g_offz = 93;
int hx, hy, hz, turetemp;
//initializes the gyroscope
void initGyro()
{
 /*
 * ITG 3200
 * power management set to:
 * clock select = internal oscillator
 * no reset, no sleep mode
 * no standby mode
 * sample rate to = 125Hz
 * parameter to +/- 2000 degrees/sec
 * low pass filter = 5Hz
 * no interrupt
 */
 writeTo(GYRO, G_PWR_MGM, 0x00);
 writeTo(GYRO, G_SMPLRT_DIV, 0x07); // EB, 50, 80, 7F, DE, 23, 20, FF
 writeTo(GYRO, G_DLPF_FS, 0x1E);    // +/- 2000 dgrs/sec, 1KHz, 1E, 19
 writeTo(GYRO, G_INT_CFG, 0x00);
}
void getGyroscopeData(int * result)
{
 /*
 Gyro ITG-3200 I2C
 registers:
 temp MSB = 1B, temp LSB = 1C
 x axis MSB = 1D, x axis LSB = 1E
 y axis MSB = 1F, y axis LSB = 20
 z axis MSB = 21, z axis LSB = 22
*/
 int regAddress = 0x1B;
 int temp, x, y, z;
 byte buff[G_TO_READ];
 readFrom(GYRO, regAddress, G_TO_READ, buff); //read the gyro data from the ITG3200
 result[0] = ((buff[2] << 8) | buff[3]) + g_offx;
 result[1] = ((buff[4] << 8) | buff[5]) + g_offy;
 result[2] = ((buff[6] << 8) | buff[7]) + g_offz;
 result[3] = (buff[0] << 8) | buff[1];       // temperature
 }

void setup()
{
 Serial.begin(9600);
 Wire.begin();
 initGyro();
}

void loop()
{
 byte addr;
 int gyro[4];
 getGyroscopeData(gyro);
 hx = gyro[0] / 14.375;
 hy = gyro[1] / 14.375;
 hz = gyro[2] / 14.375;
 turetemp = 35+ ((double) (gyro[3] + 13200)) / 280; // temperature
 Serial.print(" X=");
 Serial.print(hx);
 Serial.print(" Y=");
 Serial.print(hy);
 Serial.print(" Z=");
 Serial.print(hz);
 Serial.print(" F=");
 Serial.print(turetemp);
 Serial.print((char)223);
 Serial.println("C");
 delay(100); 
}
//---------------- Functions
//Writes val to address register on ACC
void writeTo(int DEVICE, byte address, byte val) {
  Wire.beginTransmission(DEVICE); //start transmission to ACC 
  Wire.write(address);        // send register address
  Wire.write(val);        // send value to write
  Wire.endTransmission(); //end transmission
}
//reads num bytes starting from address register on ACC in to buff array
 void readFrom(int DEVICE, byte address, int num, byte buff[]) {
 Wire.beginTransmission(DEVICE); //start transmission to ACC 
 Wire.write(address);        //sends address to read from
 Wire.endTransmission(); //end transmission
 
 Wire.beginTransmission(DEVICE); //start transmission to ACC
 Wire.requestFrom(DEVICE, num);    // request 6 bytes from ACC
 
 int i = 0;
 while(Wire.available())    //ACC may send less than requested (abnormal)
 { 
   buff[i] = Wire.read(); // receive a byte
   i++;
 }
 Wire.endTransmission(); //end transmission
}