NOT FINISHED YET!!! My first try to get a self built fully working Quadrocopter based on an mbed, a self built frame and some other more or less cheap parts.
Sensors/Gyro/L3G4200D.cpp
- Committer:
- maetugr
- Date:
- 2012-10-29
- Revision:
- 15:753c5d6a63b3
- Parent:
- 14:cf260677ecde
- Child:
- 16:74a6531350b5
File content as of revision 15:753c5d6a63b3:
#include "mbed.h" #include "L3G4200D.h" #include <math.h> #define L3G4200D_I2C_ADDRESS 0xD0 L3G4200D::L3G4200D(PinName sda, PinName scl) : i2c(sda, scl) { i2c.frequency(400000); // Turns on the L3G4200D's gyro and places it in normal mode. // Normal power mode, all axes enabled //writeReg(L3G4200D_CTRL_REG2, 0x05); // control filter writeReg(L3G4200D_CTRL_REG2, 0x00); // highpass filter disabled writeReg(L3G4200D_CTRL_REG3, 0x00); writeReg(L3G4200D_CTRL_REG4, 0x20); // acuracy 2000 dps writeReg(L3G4200D_REFERENCE, 0x00); //writeReg(L3G4200D_STATUS_REG, 0x0F); writeReg(L3G4200D_INT1_THS_XH, 0x2C); writeReg(L3G4200D_INT1_THS_XL, 0xA4); writeReg(L3G4200D_INT1_THS_YH, 0x2C); writeReg(L3G4200D_INT1_THS_YL, 0xA4); writeReg(L3G4200D_INT1_THS_ZH, 0x2C); writeReg(L3G4200D_INT1_THS_ZL, 0xA4); //writeReg(L3G4200D_INT1_DURATION, 0x00); //writeReg(L3G4200D_CTRL_REG5, 0x12); // Filter einschalten //writeReg(L3G4200D_CTRL_REG5, 0x01); // hochpass Filter einschalten writeReg(L3G4200D_CTRL_REG5, 0x00); // Filter ausschalten writeReg(L3G4200D_CTRL_REG1, 0x0F); // Gogo // calibrate gyro with an average of count samples (result to offset) #define count 50 for (int j = 0; j < 3; j++) offset[j] = 0; float Gyro_calib[3] = {0,0,0}; // temporary to sum up for (int i = 0; i < count; i++) { read(); for (int j = 0; j < 3; j++) Gyro_calib[j] += data[j]; wait(0.001); // maybe less or no wait !! } for (int j = 0; j < 3; j++) offset[j] = Gyro_calib[j]/count; } // Writes a gyro register void L3G4200D::writeReg(byte reg, byte value) { byte buffer[2]; buffer[0] = reg; buffer[1] = value; i2c.write(L3G4200D_I2C_ADDRESS, buffer, 2); } // Reads a gyro register byte L3G4200D::readReg(byte reg) { byte value = 0; i2c.write(L3G4200D_I2C_ADDRESS, ®, 1); i2c.read(L3G4200D_I2C_ADDRESS, &value, 1); return value; } // Reads the 3 gyro channels and stores them in vector g void L3G4200D::read() { byte buffer[6]; // 8-Bit pieces of axis data // assert the MSB of the address to get the gyro // to do slave-transmit subaddress updating. buffer[0] = L3G4200D_OUT_X_L | (1 << 7); i2c.write(L3G4200D_I2C_ADDRESS, buffer, 1, true); i2c.read(L3G4200D_I2C_ADDRESS, buffer, 6, true); data[0] = (short) (buffer[1] << 8 | buffer[0]); data[1] = (short) (buffer[3] << 8 | buffer[2]); data[2] = (short) (buffer[5] << 8 | buffer[4]); //with offset of calibration for (int j = 0; j < 3; j++) data[j] -= offset[j]; } // Reads the gyros Temperature int L3G4200D::readTemp() { return (short) readReg(L3G4200D_OUT_TEMP); }