Arduino Study

Gyro1

#include <Wire.h>

#define CTRL_REG1 0x20
#define CTRL_REG2 0x21
#define CTRL_REG3 0x22
#define CTRL_REG4 0x23
#define CTRL_REG5 0x24

// I2C address of the L3G4200D.
// Use I2C scanner to find this value!
int L3G4200D_Address = 105;


// Delta angles (raw input from gyro)
int x = 0;
int y = 0;
int z = 0;




void setup()
{
  Wire.begin();
  Serial.begin(9600);
  Serial.println("Starting up L3G4200D");
  setupL3G4200D(2000); // Configure L3G4200  - 250, 500 or 2000 deg/sec
  delay(1500); // wait for the sensor to be ready 
 
}

void loop()
{
  getGyroValues();

  Serial.print("X=");
  Serial.print(x,DEC);
  Serial.print("\t");
  Serial.print("y=");
  Serial.print(y,DEC);
  Serial.print("\t");
  Serial.print("z=");
  Serial.print(z,DEC);
  Serial.print("\t");
  Serial.println();
   
  delay(100);
}





void getGyroValues() {
  byte xMSB = readRegister(L3G4200D_Address, 0x29);
  byte xLSB = readRegister(L3G4200D_Address, 0x28);
  x = ((xMSB << 8) | xLSB);

  byte yMSB = readRegister(L3G4200D_Address, 0x2B);
  byte yLSB = readRegister(L3G4200D_Address, 0x2A);
  y = ((yMSB << 8) | yLSB);

  byte zMSB = readRegister(L3G4200D_Address, 0x2D);
  byte zLSB = readRegister(L3G4200D_Address, 0x2C);
  z = ((zMSB << 8) | zLSB);
}

int setupL3G4200D(int scale) {
  //From  Jim Lindblom of Sparkfun's code

  // Enable x, y, z and turn off power down:
  writeRegister(L3G4200D_Address, CTRL_REG1, 0b00001111);

  // If you'd like to adjust/use the HPF, you can edit the line below to configure CTRL_REG2:
  writeRegister(L3G4200D_Address, CTRL_REG2, 0b00000000);

  // Configure CTRL_REG3 to generate data ready interrupt on INT2
  // No interrupts used on INT1, if you'd like to configure INT1
  // or INT2 otherwise, consult the datasheet:
  writeRegister(L3G4200D_Address, CTRL_REG3, 0b00001000);

  // CTRL_REG4 controls the full-scale range, among other things:

  if(scale == 250) {
    writeRegister(L3G4200D_Address, CTRL_REG4, 0b00000000);
  } else if(scale == 500) {
    writeRegister(L3G4200D_Address, CTRL_REG4, 0b00010000);
  } else {
    writeRegister(L3G4200D_Address, CTRL_REG4, 0b00110000);
  }

  // CTRL_REG5 controls high-pass filtering of outputs, use it
  // if you'd like:
  writeRegister(L3G4200D_Address, CTRL_REG5, 0b00000000);
}

void writeRegister(int deviceAddress, byte address, byte val)
{
    Wire.beginTransmission(deviceAddress); // start transmission to device 
    Wire.write(address);       // send register address
    Wire.write(val);         // send value to write
    Wire.endTransmission();     // end transmission
}

int readRegister(int deviceAddress, byte address)
{
    int v;
    Wire.beginTransmission(deviceAddress);
    Wire.write(address); // register to read
    Wire.endTransmission();

    Wire.requestFrom(deviceAddress, 1); // read a byte

    while(!Wire.available()) {
        // waiting
    }
    v = Wire.read();
    return v;
}