IMU 10dof MEMS from DR Robot adapted from HK10DOF Changed gyro to ITG3200
Fork of HK10DOF by
WARNING: This project is not complete, but this library seems ok so far.
I have the module DFRobotics.com 10DOF MEMS IMU. I wanted a concise module for resolving direction and movement.
I found HK10DOF library (http://developer.mbed.org/users/pommzorz/code/HK10DOF/) with quaternions. But it used a different gyro. So I modified that code to use the same higher level calls but use the ITG3200 low level calls.
Diff: L3G4200D.cpp
- Revision:
- 0:9a1682a09c50
diff -r 000000000000 -r 9a1682a09c50 L3G4200D.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/L3G4200D.cpp Wed Jul 17 18:50:28 2013 +0000 @@ -0,0 +1,165 @@ +/** + * Copyright (c) 2011 Pololu Corporation. For more information, see + * + * http://www.pololu.com/ + * http://forum.pololu.com/ + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, + * copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following + * conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES + * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT + * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#include "mbed.h" +#include "L3G4200D.h" +#include <math.h> + +// Defines //////////////////////////////////////////////////////////////// + +// The Arduino two-wire interface uses a 7-bit number for the address, +// and sets the last bit correctly based on reads and writes +// mbed I2C libraries take the 7-bit address shifted left 1 bit +// #define GYR_ADDRESS (0xD2 >> 1) +#define GYR_ADDRESS 0xD2 + +// Public Methods ////////////////////////////////////////////////////////////// + +// Constructor +L3G4200D::L3G4200D(PinName sda, PinName scl): + _device(sda, scl) +{ + _device.frequency(400000); + // Turns on the L3G4200D's gyro and places it in normal mode. + // 0x0F = 0b00001111 + // Normal power mode, all axes enabled + writeReg(L3G4200D_CTRL_REG1, 0x0F); + writeReg(L3G4200D_CTRL_REG4, 0x20); // 2000 dps full scale + + setGains(1.0,1.0,1.0); + setOffsets(0.0,0.0,0.0); + +} + +// Writes a gyro register +void L3G4200D::writeReg(byte reg, byte value) +{ + data[0] = reg; + data[1] = value; + + _device.write(GYR_ADDRESS, data, 2); +} + +// Reads a gyro register +byte L3G4200D::readReg(byte reg) +{ + byte value = 0; + + _device.write(GYR_ADDRESS, ®, 1); + _device.read(GYR_ADDRESS, &value, 1); + + return value; +} + +void L3G4200D::setGains(float _Xgain, float _Ygain, float _Zgain) { + gains[0] = _Xgain; + gains[1] = _Ygain; + gains[2] = _Zgain; +} + +void L3G4200D::setOffsets(int _Xoffset, int _Yoffset, int _Zoffset) { + offsets[0] = _Xoffset; + offsets[1] = _Yoffset; + offsets[2] = _Zoffset; +} + +void L3G4200D::setRevPolarity(bool _Xpol, bool _Ypol, bool _Zpol) { + polarities[0] = _Xpol ? -1 : 1; + polarities[1] = _Ypol ? -1 : 1; + polarities[2] = _Zpol ? -1 : 1; +} + + +void L3G4200D::zeroCalibrate(unsigned int totSamples, unsigned int sampleDelayMS) { + int xyz[3]; + float tmpOffsets[] = {0,0,0}; + + for (int i = 0;i < totSamples;i++){ + wait_ms(sampleDelayMS); + read(xyz); + tmpOffsets[0] += xyz[0]; + tmpOffsets[1] += xyz[1]; + tmpOffsets[2] += xyz[2]; + } + setOffsets(-tmpOffsets[0] / totSamples, -tmpOffsets[1] / totSamples, -tmpOffsets[2] / totSamples); +} + + +// Reads the 3 gyro channels and stores them in vector g +void L3G4200D::read(int *g) +{ + // assert the MSB of the address to get the gyro + // to do slave-transmit subaddress updating. + data[0] = L3G4200D_OUT_X_L | (1 << 7); + _device.write(GYR_ADDRESS, data, 1); + +// Wire.requestFrom(GYR_ADDRESS, 6); +// while (Wire.available() < 6); + + _device.read(GYR_ADDRESS, data, 6); + + uint8_t xla = data[0]; + uint8_t xha = data[1]; + uint8_t yla = data[2]; + uint8_t yha = data[3]; + uint8_t zla = data[4]; + uint8_t zha = data[5]; + + g[0] = (short) (yha << 8 | yla); + g[1] = (short) (xha << 8 | xla); + g[2] = (short) (zha << 8 | zla); +} + +void L3G4200D::readRawCal(int *_GyroXYZ) { + read(_GyroXYZ); + _GyroXYZ[0] += offsets[0]; + _GyroXYZ[1] += offsets[1]; + _GyroXYZ[2] += offsets[2]; +} + + + +void L3G4200D::read3(int x, int y, int z) { + int* readings; + read(readings); + + // each axis reading comes in 10 bit resolution, ie 2 bytes. Least Significat Byte first!! + // thus we are converting both bytes in to one int + x = readings[0]; + y = readings[1]; + z = readings[2]; +} + +void L3G4200D::readFin(float *_GyroXYZ){ + int xyz[3]; + + readRawCal(xyz); // x,y,z will contain calibrated integer values from the sensor + _GyroXYZ[0] = xyz[0] / 14.375 * polarities[0] * gains[0]; + _GyroXYZ[1] = xyz[1]/ 14.375 * polarities[1] * gains[1]; + _GyroXYZ[2] = xyz[2] / 14.375 * polarities[2] * gains[2]; +}