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184 | #include "GY_85.h"
void GY_85::SetAccelerometer()
{
//Put the ADXL345 into +/- 4G range by writing the value 0x01 to the DATA_FORMAT register.
Wire.beginTransmission( ADXL345 ); // start transmission to device
Wire.write( 0x31 ); // send register address
Wire.write( 0x01 ); // send value to write
Wire.endTransmission(); // end transmission
//Put the ADXL345 into Measurement Mode by writing 0x08 to the POWER_CTL register.
Wire.beginTransmission( ADXL345 ); // start transmission to device
Wire.write( 0x2D ); // send register address //Power Control Register
Wire.write( 0x08 ); // send value to write
Wire.endTransmission(); // end transmission
}
float* GY_85::readFromAccelerometer()
{
static float axis[3];
int buff[6];
Wire.beginTransmission( ADXL345 ); // start transmission to device
Wire.write( DATAX0 ); // sends address to read from
Wire.endTransmission(); // end transmission
Wire.beginTransmission( ADXL345 ); // start transmission to device
Wire.requestFrom( ADXL345, 6 ); // request 6 bytes from device
uint8_t i = 0;
while(Wire.available()) // device may send less than requested (abnormal)
{
buff[i] = Wire.read(); // receive a byte
i++;
}
Wire.endTransmission(); // end transmission
axis[0] = (((buff[1]) << 8) | buff[0]);
axis[1] = (((buff[3]) << 8) | buff[2]);
axis[2] = (((buff[5]) << 8) | buff[4]);
return axis;
}
//----------------------------------------
void GY_85::SetCompass()
{
Wire.beginTransmission( HMC5883 ); //open communication with HMC5883
Wire.write( 0x00 ); //select mode register
Wire.write( 0x10 ); //15Hz, 1 sample avg, positive bias
Wire.endTransmission();
Wire.beginTransmission( HMC5883 ); //open communication with HMC5883
Wire.write( 0x01 ); //select mode register
Wire.write( 0x20 ); //+- 1.3Ga -> 0.92 mg/LSb
Wire.endTransmission();
Wire.beginTransmission( HMC5883 ); //open communication with HMC5883
Wire.write( 0x02 ); //select mode register
Wire.write( 0x00 ); //continuous measurement mode
Wire.endTransmission();
}
float* GY_85::readFromCompass()
{
static float axis[3];
//Tell the HMC5883 where to begin reading data
Wire.beginTransmission( HMC5883 );
Wire.write( 0x03 ); //select register 3, X MSB register
Wire.endTransmission();
delay(67);
//Read data from each axis, 2 registers per axis
Wire.beginTransmission( HMC5883 );
Wire.requestFrom( HMC5883, 6 );
if(6<=Wire.available()){
axis[0] = (Wire.read() << 8) | Wire.read();
axis[2] = (Wire.read() << 8) | Wire.read();
axis[1] = (Wire.read() << 8) | Wire.read();
}
return axis;
}
//----------------------------------------
int g_offx = 0;
int g_offy = 0;
int g_offz = 0;
void GY_85::SetGyro()
{
Wire.beginTransmission( ITG3200 );
Wire.write( 0x3E );
Wire.write( 0x00 );
Wire.endTransmission();
delay(10);
Wire.beginTransmission( ITG3200 );
Wire.write( 0x15 );
Wire.write( 0x07 );
Wire.endTransmission();
delay(10);
Wire.beginTransmission( ITG3200 );
Wire.write( 0x16 );
Wire.write( 0x1E ); // +/- 2000 dgrs/sec, 1KHz, 1E, 19
Wire.endTransmission();
delay(10);
Wire.beginTransmission( ITG3200 );
Wire.write( 0x17 );
Wire.write( 0x00 );
Wire.endTransmission();
delay(10);
GyroCalibrate();
}
void GY_85::GyroCalibrate()
{
static int tmpx = 0;
static int tmpy = 0;
static int tmpz = 0;
g_offx = 0;
g_offy = 0;
g_offz = 0;
for( uint8_t i = 0; i < 100; i ++ ) //take the mean from 10 gyro probes and divide it from the current probe
{
delay(10);
float* gp = readGyro();
tmpx += *( gp);
tmpy += *(++gp);
tmpz += *(++gp);
}
g_offx = tmpx/100;
g_offy = tmpy/100;
g_offz = tmpz/100;
}
float* GY_85::readGyro()
{
static float axis[4];
Wire.beginTransmission( ITG3200 );
Wire.write( 0x1B );
Wire.endTransmission();
Wire.beginTransmission( ITG3200 );
Wire.requestFrom( ITG3200, 8 ); // request 8 bytes from ITG3200
int i = 0;
uint8_t buff[8];
while(Wire.available())
{
buff[i] = Wire.read();
i++;
}
Wire.endTransmission();
axis[0] = ((buff[4] << 8) | buff[5]) - g_offx;
axis[1] = ((buff[2] << 8) | buff[3]) - g_offy;
axis[2] = ((buff[6] << 8) | buff[7]) - g_offz;
axis[3] = ((buff[0] << 8) | buff[1]); // temperature
return axis;
}
void GY_85::init()
{
SetAccelerometer();
SetCompass();
SetGyro();
}
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