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MPU9250.cpp@1:b36bbc1c6d27, 2020-04-11 (annotated)
- Committer:
- demayer
- Date:
- Sat Apr 11 08:15:48 2020 +0000
- Revision:
- 1:b36bbc1c6d27
- Child:
- 2:c7897a3f5f11
IMU-library in .h und .cpp file aufgeteilt
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
demayer | 1:b36bbc1c6d27 | 1 | #include "MPU9250.h" |
demayer | 1:b36bbc1c6d27 | 2 | |
demayer | 1:b36bbc1c6d27 | 3 | |
demayer | 1:b36bbc1c6d27 | 4 | |
demayer | 1:b36bbc1c6d27 | 5 | uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G |
demayer | 1:b36bbc1c6d27 | 6 | uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS |
demayer | 1:b36bbc1c6d27 | 7 | uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution |
demayer | 1:b36bbc1c6d27 | 8 | uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR |
demayer | 1:b36bbc1c6d27 | 9 | float aRes, gRes, mRes; // scale resolutions per LSB for the sensors |
demayer | 1:b36bbc1c6d27 | 10 | |
demayer | 1:b36bbc1c6d27 | 11 | //Set up I2C, (SDA,SCL) |
demayer | 1:b36bbc1c6d27 | 12 | I2C i2c(PB_9, PB_8); |
demayer | 1:b36bbc1c6d27 | 13 | |
demayer | 1:b36bbc1c6d27 | 14 | DigitalOut myled(LED1); |
demayer | 1:b36bbc1c6d27 | 15 | |
demayer | 1:b36bbc1c6d27 | 16 | // Pin definitions |
demayer | 1:b36bbc1c6d27 | 17 | int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins |
demayer | 1:b36bbc1c6d27 | 18 | |
demayer | 1:b36bbc1c6d27 | 19 | int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output |
demayer | 1:b36bbc1c6d27 | 20 | int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output |
demayer | 1:b36bbc1c6d27 | 21 | int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output |
demayer | 1:b36bbc1c6d27 | 22 | float magCalibration[3] = {0, 0, 0}, magbias[3] = {0, 0, 0}; // Factory mag calibration and mag bias |
demayer | 1:b36bbc1c6d27 | 23 | float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer |
demayer | 1:b36bbc1c6d27 | 24 | float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values |
demayer | 1:b36bbc1c6d27 | 25 | int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius |
demayer | 1:b36bbc1c6d27 | 26 | float temperature; |
demayer | 1:b36bbc1c6d27 | 27 | float SelfTest[6]; |
demayer | 1:b36bbc1c6d27 | 28 | |
demayer | 1:b36bbc1c6d27 | 29 | int delt_t = 0; // used to control display output rate |
demayer | 1:b36bbc1c6d27 | 30 | int _count = 0; // used to control display output rate |
demayer | 1:b36bbc1c6d27 | 31 | |
demayer | 1:b36bbc1c6d27 | 32 | // parameters for 6 DoF sensor fusion calculations |
demayer | 1:b36bbc1c6d27 | 33 | float PI = 3.14159265358979323846f; |
demayer | 1:b36bbc1c6d27 | 34 | float GyroMeasError = PI * (60.0f / 180.0f); // gyroscope measurement error in rads/s (start at 60 deg/s), then reduce after ~10 s to 3 |
demayer | 1:b36bbc1c6d27 | 35 | float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta |
demayer | 1:b36bbc1c6d27 | 36 | float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s) |
demayer | 1:b36bbc1c6d27 | 37 | float zeta = sqrt(3.0f / 4.0f) * GyroMeasDrift; // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value |
demayer | 1:b36bbc1c6d27 | 38 | #define Kp 2.0f * 5.0f // these are the free parameters in the Mahony filter and fusion scheme, Kp for proportional feedback, Ki for integral |
demayer | 1:b36bbc1c6d27 | 39 | #define Ki 0.0f |
demayer | 1:b36bbc1c6d27 | 40 | |
demayer | 1:b36bbc1c6d27 | 41 | float pitch, yaw, roll; |
demayer | 1:b36bbc1c6d27 | 42 | float vx, vy, vz; |
demayer | 1:b36bbc1c6d27 | 43 | float deltat = 0.0f; // integration interval for both filter schemes |
demayer | 1:b36bbc1c6d27 | 44 | int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval |
demayer | 1:b36bbc1c6d27 | 45 | float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion |
demayer | 1:b36bbc1c6d27 | 46 | float v_trans[3] = {0.0f, 0.0f, 0.0f}; // vector to hold translative velocities |
demayer | 1:b36bbc1c6d27 | 47 | float a_old[3] = {0.00f, 0.00f, 0.00f}; |
demayer | 1:b36bbc1c6d27 | 48 | float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method |
demayer | 1:b36bbc1c6d27 | 49 | |
demayer | 1:b36bbc1c6d27 | 50 | |
demayer | 1:b36bbc1c6d27 | 51 | accData_t myData; |
demayer | 1:b36bbc1c6d27 | 52 | MPU9250 mpu9250; |
demayer | 1:b36bbc1c6d27 | 53 | Timer t; |
demayer | 1:b36bbc1c6d27 | 54 | Serial pc(USBTX, USBRX); // tx, rx |
demayer | 1:b36bbc1c6d27 | 55 | |
demayer | 1:b36bbc1c6d27 | 56 | #define SAMPLE_TIME 100 |
demayer | 1:b36bbc1c6d27 | 57 | |
demayer | 1:b36bbc1c6d27 | 58 | |
demayer | 1:b36bbc1c6d27 | 59 | float sum = 0; |
demayer | 1:b36bbc1c6d27 | 60 | uint32_t sumCount = 0; |
demayer | 1:b36bbc1c6d27 | 61 | char buffer[14]; |
demayer | 1:b36bbc1c6d27 | 62 | |
demayer | 1:b36bbc1c6d27 | 63 | |
demayer | 1:b36bbc1c6d27 | 64 | //=================================================================================================================== |
demayer | 1:b36bbc1c6d27 | 65 | //====== Set of useful function to access acceleratio, gyroscope, and temperature data |
demayer | 1:b36bbc1c6d27 | 66 | //=================================================================================================================== |
demayer | 1:b36bbc1c6d27 | 67 | |
demayer | 1:b36bbc1c6d27 | 68 | void MPU9250::writeByte(uint8_t address, uint8_t subAddress, uint8_t data) |
demayer | 1:b36bbc1c6d27 | 69 | { |
demayer | 1:b36bbc1c6d27 | 70 | char data_write[2]; |
demayer | 1:b36bbc1c6d27 | 71 | data_write[0] = subAddress; |
demayer | 1:b36bbc1c6d27 | 72 | data_write[1] = data; |
demayer | 1:b36bbc1c6d27 | 73 | i2c.write(address, data_write, 2, 0); |
demayer | 1:b36bbc1c6d27 | 74 | } |
demayer | 1:b36bbc1c6d27 | 75 | |
demayer | 1:b36bbc1c6d27 | 76 | char MPU9250::readByte(uint8_t address, uint8_t subAddress) |
demayer | 1:b36bbc1c6d27 | 77 | { |
demayer | 1:b36bbc1c6d27 | 78 | char data[1]; // `data` will store the register data |
demayer | 1:b36bbc1c6d27 | 79 | char data_write[1]; |
demayer | 1:b36bbc1c6d27 | 80 | data_write[0] = subAddress; |
demayer | 1:b36bbc1c6d27 | 81 | i2c.write(address, data_write, 1, 1); // no stop |
demayer | 1:b36bbc1c6d27 | 82 | i2c.read(address, data, 1, 0); |
demayer | 1:b36bbc1c6d27 | 83 | return data[0]; |
demayer | 1:b36bbc1c6d27 | 84 | } |
demayer | 1:b36bbc1c6d27 | 85 | |
demayer | 1:b36bbc1c6d27 | 86 | void MPU9250::readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) |
demayer | 1:b36bbc1c6d27 | 87 | { |
demayer | 1:b36bbc1c6d27 | 88 | char data[14]; |
demayer | 1:b36bbc1c6d27 | 89 | char data_write[1]; |
demayer | 1:b36bbc1c6d27 | 90 | data_write[0] = subAddress; |
demayer | 1:b36bbc1c6d27 | 91 | i2c.write(address, data_write, 1, 1); // no stop |
demayer | 1:b36bbc1c6d27 | 92 | i2c.read(address, data, count, 0); |
demayer | 1:b36bbc1c6d27 | 93 | for(int ii = 0; ii < count; ii++) { |
demayer | 1:b36bbc1c6d27 | 94 | dest[ii] = data[ii]; |
demayer | 1:b36bbc1c6d27 | 95 | } |
demayer | 1:b36bbc1c6d27 | 96 | } |
demayer | 1:b36bbc1c6d27 | 97 | |
demayer | 1:b36bbc1c6d27 | 98 | |
demayer | 1:b36bbc1c6d27 | 99 | void MPU9250::getMres() |
demayer | 1:b36bbc1c6d27 | 100 | { |
demayer | 1:b36bbc1c6d27 | 101 | switch (Mscale) { |
demayer | 1:b36bbc1c6d27 | 102 | // Possible magnetometer scales (and their register bit settings) are: |
demayer | 1:b36bbc1c6d27 | 103 | // 14 bit resolution (0) and 16 bit resolution (1) |
demayer | 1:b36bbc1c6d27 | 104 | case MFS_14BITS: |
demayer | 1:b36bbc1c6d27 | 105 | mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss |
demayer | 1:b36bbc1c6d27 | 106 | break; |
demayer | 1:b36bbc1c6d27 | 107 | case MFS_16BITS: |
demayer | 1:b36bbc1c6d27 | 108 | mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss |
demayer | 1:b36bbc1c6d27 | 109 | break; |
demayer | 1:b36bbc1c6d27 | 110 | } |
demayer | 1:b36bbc1c6d27 | 111 | } |
demayer | 1:b36bbc1c6d27 | 112 | |
demayer | 1:b36bbc1c6d27 | 113 | |
demayer | 1:b36bbc1c6d27 | 114 | void MPU9250::getGres() |
demayer | 1:b36bbc1c6d27 | 115 | { |
demayer | 1:b36bbc1c6d27 | 116 | switch (Gscale) { |
demayer | 1:b36bbc1c6d27 | 117 | // Possible gyro scales (and their register bit settings) are: |
demayer | 1:b36bbc1c6d27 | 118 | // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11). |
demayer | 1:b36bbc1c6d27 | 119 | // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: |
demayer | 1:b36bbc1c6d27 | 120 | case GFS_250DPS: |
demayer | 1:b36bbc1c6d27 | 121 | gRes = 250.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 122 | break; |
demayer | 1:b36bbc1c6d27 | 123 | case GFS_500DPS: |
demayer | 1:b36bbc1c6d27 | 124 | gRes = 500.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 125 | break; |
demayer | 1:b36bbc1c6d27 | 126 | case GFS_1000DPS: |
demayer | 1:b36bbc1c6d27 | 127 | gRes = 1000.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 128 | break; |
demayer | 1:b36bbc1c6d27 | 129 | case GFS_2000DPS: |
demayer | 1:b36bbc1c6d27 | 130 | gRes = 2000.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 131 | break; |
demayer | 1:b36bbc1c6d27 | 132 | } |
demayer | 1:b36bbc1c6d27 | 133 | } |
demayer | 1:b36bbc1c6d27 | 134 | |
demayer | 1:b36bbc1c6d27 | 135 | |
demayer | 1:b36bbc1c6d27 | 136 | void MPU9250::getAres() |
demayer | 1:b36bbc1c6d27 | 137 | { |
demayer | 1:b36bbc1c6d27 | 138 | switch (Ascale) { |
demayer | 1:b36bbc1c6d27 | 139 | // Possible accelerometer scales (and their register bit settings) are: |
demayer | 1:b36bbc1c6d27 | 140 | // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11). |
demayer | 1:b36bbc1c6d27 | 141 | // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: |
demayer | 1:b36bbc1c6d27 | 142 | case AFS_2G: |
demayer | 1:b36bbc1c6d27 | 143 | aRes = 2.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 144 | break; |
demayer | 1:b36bbc1c6d27 | 145 | case AFS_4G: |
demayer | 1:b36bbc1c6d27 | 146 | aRes = 4.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 147 | break; |
demayer | 1:b36bbc1c6d27 | 148 | case AFS_8G: |
demayer | 1:b36bbc1c6d27 | 149 | aRes = 8.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 150 | break; |
demayer | 1:b36bbc1c6d27 | 151 | case AFS_16G: |
demayer | 1:b36bbc1c6d27 | 152 | aRes = 16.0/32768.0; |
demayer | 1:b36bbc1c6d27 | 153 | break; |
demayer | 1:b36bbc1c6d27 | 154 | } |
demayer | 1:b36bbc1c6d27 | 155 | } |
demayer | 1:b36bbc1c6d27 | 156 | |
demayer | 1:b36bbc1c6d27 | 157 | |
demayer | 1:b36bbc1c6d27 | 158 | void MPU9250::readAccelData(int16_t * destination) |
demayer | 1:b36bbc1c6d27 | 159 | { |
demayer | 1:b36bbc1c6d27 | 160 | uint8_t rawData[6]; // x/y/z accel register data stored here |
demayer | 1:b36bbc1c6d27 | 161 | readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array |
demayer | 1:b36bbc1c6d27 | 162 | destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value |
demayer | 1:b36bbc1c6d27 | 163 | destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; |
demayer | 1:b36bbc1c6d27 | 164 | destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; |
demayer | 1:b36bbc1c6d27 | 165 | } |
demayer | 1:b36bbc1c6d27 | 166 | |
demayer | 1:b36bbc1c6d27 | 167 | void MPU9250::readGyroData(int16_t * destination) |
demayer | 1:b36bbc1c6d27 | 168 | { |
demayer | 1:b36bbc1c6d27 | 169 | uint8_t rawData[6]; // x/y/z gyro register data stored here |
demayer | 1:b36bbc1c6d27 | 170 | readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array |
demayer | 1:b36bbc1c6d27 | 171 | destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value |
demayer | 1:b36bbc1c6d27 | 172 | destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; |
demayer | 1:b36bbc1c6d27 | 173 | destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; |
demayer | 1:b36bbc1c6d27 | 174 | } |
demayer | 1:b36bbc1c6d27 | 175 | |
demayer | 1:b36bbc1c6d27 | 176 | void MPU9250::readMagData(int16_t * destination) |
demayer | 1:b36bbc1c6d27 | 177 | { |
demayer | 1:b36bbc1c6d27 | 178 | uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition |
demayer | 1:b36bbc1c6d27 | 179 | if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set |
demayer | 1:b36bbc1c6d27 | 180 | readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array |
demayer | 1:b36bbc1c6d27 | 181 | uint8_t c = rawData[6]; // End data read by reading ST2 register |
demayer | 1:b36bbc1c6d27 | 182 | if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data |
demayer | 1:b36bbc1c6d27 | 183 | destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value |
demayer | 1:b36bbc1c6d27 | 184 | destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian |
demayer | 1:b36bbc1c6d27 | 185 | destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ; |
demayer | 1:b36bbc1c6d27 | 186 | } |
demayer | 1:b36bbc1c6d27 | 187 | } |
demayer | 1:b36bbc1c6d27 | 188 | } |
demayer | 1:b36bbc1c6d27 | 189 | |
demayer | 1:b36bbc1c6d27 | 190 | int16_t MPU9250::readTempData() |
demayer | 1:b36bbc1c6d27 | 191 | { |
demayer | 1:b36bbc1c6d27 | 192 | uint8_t rawData[2]; // x/y/z gyro register data stored here |
demayer | 1:b36bbc1c6d27 | 193 | readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array |
demayer | 1:b36bbc1c6d27 | 194 | return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value |
demayer | 1:b36bbc1c6d27 | 195 | } |
demayer | 1:b36bbc1c6d27 | 196 | |
demayer | 1:b36bbc1c6d27 | 197 | |
demayer | 1:b36bbc1c6d27 | 198 | void MPU9250::resetMPU9250() |
demayer | 1:b36bbc1c6d27 | 199 | { |
demayer | 1:b36bbc1c6d27 | 200 | // reset device |
demayer | 1:b36bbc1c6d27 | 201 | writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device |
demayer | 1:b36bbc1c6d27 | 202 | wait(0.1); |
demayer | 1:b36bbc1c6d27 | 203 | } |
demayer | 1:b36bbc1c6d27 | 204 | |
demayer | 1:b36bbc1c6d27 | 205 | void MPU9250::initAK8963(float * destination) |
demayer | 1:b36bbc1c6d27 | 206 | { |
demayer | 1:b36bbc1c6d27 | 207 | // First extract the factory calibration for each magnetometer axis |
demayer | 1:b36bbc1c6d27 | 208 | uint8_t rawData[3]; // x/y/z gyro calibration data stored here |
demayer | 1:b36bbc1c6d27 | 209 | writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer |
demayer | 1:b36bbc1c6d27 | 210 | wait(0.01); |
demayer | 1:b36bbc1c6d27 | 211 | writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode |
demayer | 1:b36bbc1c6d27 | 212 | wait(0.01); |
demayer | 1:b36bbc1c6d27 | 213 | readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values |
demayer | 1:b36bbc1c6d27 | 214 | destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc. |
demayer | 1:b36bbc1c6d27 | 215 | destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f; |
demayer | 1:b36bbc1c6d27 | 216 | destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f; |
demayer | 1:b36bbc1c6d27 | 217 | writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer |
demayer | 1:b36bbc1c6d27 | 218 | wait(0.01); |
demayer | 1:b36bbc1c6d27 | 219 | // Configure the magnetometer for continuous read and highest resolution |
demayer | 1:b36bbc1c6d27 | 220 | // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register, |
demayer | 1:b36bbc1c6d27 | 221 | // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates |
demayer | 1:b36bbc1c6d27 | 222 | writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR |
demayer | 1:b36bbc1c6d27 | 223 | wait(0.01); |
demayer | 1:b36bbc1c6d27 | 224 | } |
demayer | 1:b36bbc1c6d27 | 225 | |
demayer | 1:b36bbc1c6d27 | 226 | |
demayer | 1:b36bbc1c6d27 | 227 | void MPU9250::initMPU9250() |
demayer | 1:b36bbc1c6d27 | 228 | { |
demayer | 1:b36bbc1c6d27 | 229 | // Initialize MPU9250 device |
demayer | 1:b36bbc1c6d27 | 230 | // wake up device |
demayer | 1:b36bbc1c6d27 | 231 | writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors |
demayer | 1:b36bbc1c6d27 | 232 | wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt |
demayer | 1:b36bbc1c6d27 | 233 | |
demayer | 1:b36bbc1c6d27 | 234 | // get stable time source |
demayer | 1:b36bbc1c6d27 | 235 | writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001 |
demayer | 1:b36bbc1c6d27 | 236 | |
demayer | 1:b36bbc1c6d27 | 237 | // Configure Gyro and Accelerometer |
demayer | 1:b36bbc1c6d27 | 238 | // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively; |
demayer | 1:b36bbc1c6d27 | 239 | // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both |
demayer | 1:b36bbc1c6d27 | 240 | // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate |
demayer | 1:b36bbc1c6d27 | 241 | writeByte(MPU9250_ADDRESS, CONFIG, 0x03); |
demayer | 1:b36bbc1c6d27 | 242 | |
demayer | 1:b36bbc1c6d27 | 243 | // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV) |
demayer | 1:b36bbc1c6d27 | 244 | writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above |
demayer | 1:b36bbc1c6d27 | 245 | |
demayer | 1:b36bbc1c6d27 | 246 | // Set gyroscope full scale range |
demayer | 1:b36bbc1c6d27 | 247 | // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3 |
demayer | 1:b36bbc1c6d27 | 248 | uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG); |
demayer | 1:b36bbc1c6d27 | 249 | writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5] |
demayer | 1:b36bbc1c6d27 | 250 | writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3] |
demayer | 1:b36bbc1c6d27 | 251 | writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro |
demayer | 1:b36bbc1c6d27 | 252 | |
demayer | 1:b36bbc1c6d27 | 253 | // Set accelerometer configuration |
demayer | 1:b36bbc1c6d27 | 254 | c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG); |
demayer | 1:b36bbc1c6d27 | 255 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5] |
demayer | 1:b36bbc1c6d27 | 256 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3] |
demayer | 1:b36bbc1c6d27 | 257 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer |
demayer | 1:b36bbc1c6d27 | 258 | |
demayer | 1:b36bbc1c6d27 | 259 | // Set accelerometer sample rate configuration |
demayer | 1:b36bbc1c6d27 | 260 | // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for |
demayer | 1:b36bbc1c6d27 | 261 | // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz |
demayer | 1:b36bbc1c6d27 | 262 | c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2); |
demayer | 1:b36bbc1c6d27 | 263 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0]) |
demayer | 1:b36bbc1c6d27 | 264 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz |
demayer | 1:b36bbc1c6d27 | 265 | |
demayer | 1:b36bbc1c6d27 | 266 | // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates, |
demayer | 1:b36bbc1c6d27 | 267 | // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting |
demayer | 1:b36bbc1c6d27 | 268 | |
demayer | 1:b36bbc1c6d27 | 269 | // Configure Interrupts and Bypass Enable |
demayer | 1:b36bbc1c6d27 | 270 | // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips |
demayer | 1:b36bbc1c6d27 | 271 | // can join the I2C bus and all can be controlled by the Arduino as master |
demayer | 1:b36bbc1c6d27 | 272 | writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22); |
demayer | 1:b36bbc1c6d27 | 273 | writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt |
demayer | 1:b36bbc1c6d27 | 274 | } |
demayer | 1:b36bbc1c6d27 | 275 | |
demayer | 1:b36bbc1c6d27 | 276 | // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average |
demayer | 1:b36bbc1c6d27 | 277 | // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers. |
demayer | 1:b36bbc1c6d27 | 278 | void MPU9250::calibrateMPU9250(float * dest1, float * dest2) |
demayer | 1:b36bbc1c6d27 | 279 | { |
demayer | 1:b36bbc1c6d27 | 280 | uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data |
demayer | 1:b36bbc1c6d27 | 281 | uint16_t ii, packet_count, fifo_count; |
demayer | 1:b36bbc1c6d27 | 282 | int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0}; |
demayer | 1:b36bbc1c6d27 | 283 | |
demayer | 1:b36bbc1c6d27 | 284 | // reset device, reset all registers, clear gyro and accelerometer bias registers |
demayer | 1:b36bbc1c6d27 | 285 | writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device |
demayer | 1:b36bbc1c6d27 | 286 | wait(0.1); |
demayer | 1:b36bbc1c6d27 | 287 | |
demayer | 1:b36bbc1c6d27 | 288 | // get stable time source |
demayer | 1:b36bbc1c6d27 | 289 | // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001 |
demayer | 1:b36bbc1c6d27 | 290 | writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); |
demayer | 1:b36bbc1c6d27 | 291 | writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00); |
demayer | 1:b36bbc1c6d27 | 292 | wait(0.2); |
demayer | 1:b36bbc1c6d27 | 293 | |
demayer | 1:b36bbc1c6d27 | 294 | // Configure device for bias calculation |
demayer | 1:b36bbc1c6d27 | 295 | writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts |
demayer | 1:b36bbc1c6d27 | 296 | writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO |
demayer | 1:b36bbc1c6d27 | 297 | writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source |
demayer | 1:b36bbc1c6d27 | 298 | writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master |
demayer | 1:b36bbc1c6d27 | 299 | writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes |
demayer | 1:b36bbc1c6d27 | 300 | writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP |
demayer | 1:b36bbc1c6d27 | 301 | wait(0.015); |
demayer | 1:b36bbc1c6d27 | 302 | |
demayer | 1:b36bbc1c6d27 | 303 | // Configure MPU9250 gyro and accelerometer for bias calculation |
demayer | 1:b36bbc1c6d27 | 304 | writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz |
demayer | 1:b36bbc1c6d27 | 305 | writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz |
demayer | 1:b36bbc1c6d27 | 306 | writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity |
demayer | 1:b36bbc1c6d27 | 307 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity |
demayer | 1:b36bbc1c6d27 | 308 | |
demayer | 1:b36bbc1c6d27 | 309 | uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec |
demayer | 1:b36bbc1c6d27 | 310 | uint16_t accelsensitivity = 16384; // = 16384 LSB/g |
demayer | 1:b36bbc1c6d27 | 311 | |
demayer | 1:b36bbc1c6d27 | 312 | // Configure FIFO to capture accelerometer and gyro data for bias calculation |
demayer | 1:b36bbc1c6d27 | 313 | writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO |
demayer | 1:b36bbc1c6d27 | 314 | writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250) |
demayer | 1:b36bbc1c6d27 | 315 | wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes |
demayer | 1:b36bbc1c6d27 | 316 | |
demayer | 1:b36bbc1c6d27 | 317 | // At end of sample accumulation, turn off FIFO sensor read |
demayer | 1:b36bbc1c6d27 | 318 | writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO |
demayer | 1:b36bbc1c6d27 | 319 | readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count |
demayer | 1:b36bbc1c6d27 | 320 | fifo_count = ((uint16_t)data[0] << 8) | data[1]; |
demayer | 1:b36bbc1c6d27 | 321 | packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging |
demayer | 1:b36bbc1c6d27 | 322 | |
demayer | 1:b36bbc1c6d27 | 323 | for (ii = 0; ii < packet_count; ii++) { |
demayer | 1:b36bbc1c6d27 | 324 | int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0}; |
demayer | 1:b36bbc1c6d27 | 325 | readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging |
demayer | 1:b36bbc1c6d27 | 326 | accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO |
demayer | 1:b36bbc1c6d27 | 327 | accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ; |
demayer | 1:b36bbc1c6d27 | 328 | accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ; |
demayer | 1:b36bbc1c6d27 | 329 | gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ; |
demayer | 1:b36bbc1c6d27 | 330 | gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ; |
demayer | 1:b36bbc1c6d27 | 331 | gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ; |
demayer | 1:b36bbc1c6d27 | 332 | |
demayer | 1:b36bbc1c6d27 | 333 | accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases |
demayer | 1:b36bbc1c6d27 | 334 | accel_bias[1] += (int32_t) accel_temp[1]; |
demayer | 1:b36bbc1c6d27 | 335 | accel_bias[2] += (int32_t) accel_temp[2]; |
demayer | 1:b36bbc1c6d27 | 336 | gyro_bias[0] += (int32_t) gyro_temp[0]; |
demayer | 1:b36bbc1c6d27 | 337 | gyro_bias[1] += (int32_t) gyro_temp[1]; |
demayer | 1:b36bbc1c6d27 | 338 | gyro_bias[2] += (int32_t) gyro_temp[2]; |
demayer | 1:b36bbc1c6d27 | 339 | |
demayer | 1:b36bbc1c6d27 | 340 | } |
demayer | 1:b36bbc1c6d27 | 341 | accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases |
demayer | 1:b36bbc1c6d27 | 342 | accel_bias[1] /= (int32_t) packet_count; |
demayer | 1:b36bbc1c6d27 | 343 | accel_bias[2] /= (int32_t) packet_count; |
demayer | 1:b36bbc1c6d27 | 344 | gyro_bias[0] /= (int32_t) packet_count; |
demayer | 1:b36bbc1c6d27 | 345 | gyro_bias[1] /= (int32_t) packet_count; |
demayer | 1:b36bbc1c6d27 | 346 | gyro_bias[2] /= (int32_t) packet_count; |
demayer | 1:b36bbc1c6d27 | 347 | |
demayer | 1:b36bbc1c6d27 | 348 | if(accel_bias[2] > 0L) { |
demayer | 1:b36bbc1c6d27 | 349 | accel_bias[2] -= (int32_t) accelsensitivity; // Remove gravity from the z-axis accelerometer bias calculation |
demayer | 1:b36bbc1c6d27 | 350 | } else { |
demayer | 1:b36bbc1c6d27 | 351 | accel_bias[2] += (int32_t) accelsensitivity; |
demayer | 1:b36bbc1c6d27 | 352 | } |
demayer | 1:b36bbc1c6d27 | 353 | |
demayer | 1:b36bbc1c6d27 | 354 | // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup |
demayer | 1:b36bbc1c6d27 | 355 | data[0] = (-gyro_bias[0]/4 >> 8) & 0xFF; // Divide by 4 to get 32.9 LSB per deg/s to conform to expected bias input format |
demayer | 1:b36bbc1c6d27 | 356 | data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases |
demayer | 1:b36bbc1c6d27 | 357 | data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 358 | data[3] = (-gyro_bias[1]/4) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 359 | data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 360 | data[5] = (-gyro_bias[2]/4) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 361 | |
demayer | 1:b36bbc1c6d27 | 362 | /// Push gyro biases to hardware registers |
demayer | 1:b36bbc1c6d27 | 363 | /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]); |
demayer | 1:b36bbc1c6d27 | 364 | writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]); |
demayer | 1:b36bbc1c6d27 | 365 | writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]); |
demayer | 1:b36bbc1c6d27 | 366 | writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]); |
demayer | 1:b36bbc1c6d27 | 367 | writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]); |
demayer | 1:b36bbc1c6d27 | 368 | writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]); |
demayer | 1:b36bbc1c6d27 | 369 | */ |
demayer | 1:b36bbc1c6d27 | 370 | dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction |
demayer | 1:b36bbc1c6d27 | 371 | dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity; |
demayer | 1:b36bbc1c6d27 | 372 | dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity; |
demayer | 1:b36bbc1c6d27 | 373 | |
demayer | 1:b36bbc1c6d27 | 374 | // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain |
demayer | 1:b36bbc1c6d27 | 375 | // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold |
demayer | 1:b36bbc1c6d27 | 376 | // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature |
demayer | 1:b36bbc1c6d27 | 377 | // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that |
demayer | 1:b36bbc1c6d27 | 378 | // the accelerometer biases calculated above must be divided by 8. |
demayer | 1:b36bbc1c6d27 | 379 | |
demayer | 1:b36bbc1c6d27 | 380 | int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases |
demayer | 1:b36bbc1c6d27 | 381 | readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values |
demayer | 1:b36bbc1c6d27 | 382 | accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1]; |
demayer | 1:b36bbc1c6d27 | 383 | readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]); |
demayer | 1:b36bbc1c6d27 | 384 | accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1]; |
demayer | 1:b36bbc1c6d27 | 385 | readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]); |
demayer | 1:b36bbc1c6d27 | 386 | accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1]; |
demayer | 1:b36bbc1c6d27 | 387 | |
demayer | 1:b36bbc1c6d27 | 388 | uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers |
demayer | 1:b36bbc1c6d27 | 389 | uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis |
demayer | 1:b36bbc1c6d27 | 390 | |
demayer | 1:b36bbc1c6d27 | 391 | for(ii = 0; ii < 3; ii++) { |
demayer | 1:b36bbc1c6d27 | 392 | if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit |
demayer | 1:b36bbc1c6d27 | 393 | } |
demayer | 1:b36bbc1c6d27 | 394 | |
demayer | 1:b36bbc1c6d27 | 395 | // Construct total accelerometer bias, including calculated average accelerometer bias from above |
demayer | 1:b36bbc1c6d27 | 396 | accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale) |
demayer | 1:b36bbc1c6d27 | 397 | accel_bias_reg[1] -= (accel_bias[1]/8); |
demayer | 1:b36bbc1c6d27 | 398 | accel_bias_reg[2] -= (accel_bias[2]/8); |
demayer | 1:b36bbc1c6d27 | 399 | |
demayer | 1:b36bbc1c6d27 | 400 | data[0] = (accel_bias_reg[0] >> 8) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 401 | data[1] = (accel_bias_reg[0]) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 402 | data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers |
demayer | 1:b36bbc1c6d27 | 403 | data[2] = (accel_bias_reg[1] >> 8) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 404 | data[3] = (accel_bias_reg[1]) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 405 | data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers |
demayer | 1:b36bbc1c6d27 | 406 | data[4] = (accel_bias_reg[2] >> 8) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 407 | data[5] = (accel_bias_reg[2]) & 0xFF; |
demayer | 1:b36bbc1c6d27 | 408 | data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers |
demayer | 1:b36bbc1c6d27 | 409 | |
demayer | 1:b36bbc1c6d27 | 410 | // Apparently this is not working for the acceleration biases in the MPU-9250 |
demayer | 1:b36bbc1c6d27 | 411 | // Are we handling the temperature correction bit properly? |
demayer | 1:b36bbc1c6d27 | 412 | // Push accelerometer biases to hardware registers |
demayer | 1:b36bbc1c6d27 | 413 | /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]); |
demayer | 1:b36bbc1c6d27 | 414 | writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]); |
demayer | 1:b36bbc1c6d27 | 415 | writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]); |
demayer | 1:b36bbc1c6d27 | 416 | writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]); |
demayer | 1:b36bbc1c6d27 | 417 | writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]); |
demayer | 1:b36bbc1c6d27 | 418 | writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]); |
demayer | 1:b36bbc1c6d27 | 419 | */ |
demayer | 1:b36bbc1c6d27 | 420 | // Output scaled accelerometer biases for manual subtraction in the main program |
demayer | 1:b36bbc1c6d27 | 421 | dest2[0] = (float)accel_bias[0]/(float)accelsensitivity; |
demayer | 1:b36bbc1c6d27 | 422 | dest2[1] = (float)accel_bias[1]/(float)accelsensitivity; |
demayer | 1:b36bbc1c6d27 | 423 | dest2[2] = (float)accel_bias[2]/(float)accelsensitivity; |
demayer | 1:b36bbc1c6d27 | 424 | } |
demayer | 1:b36bbc1c6d27 | 425 | |
demayer | 1:b36bbc1c6d27 | 426 | |
demayer | 1:b36bbc1c6d27 | 427 | // Accelerometer and gyroscope self test; check calibration wrt factory settings |
demayer | 1:b36bbc1c6d27 | 428 | void MPU9250::MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass |
demayer | 1:b36bbc1c6d27 | 429 | { |
demayer | 1:b36bbc1c6d27 | 430 | uint8_t rawData[6] = {0, 0, 0, 0, 0, 0}; |
demayer | 1:b36bbc1c6d27 | 431 | uint8_t selfTest[6]; |
demayer | 1:b36bbc1c6d27 | 432 | int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3]; |
demayer | 1:b36bbc1c6d27 | 433 | float factoryTrim[6]; |
demayer | 1:b36bbc1c6d27 | 434 | uint8_t FS = 0; |
demayer | 1:b36bbc1c6d27 | 435 | |
demayer | 1:b36bbc1c6d27 | 436 | writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz |
demayer | 1:b36bbc1c6d27 | 437 | writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz |
demayer | 1:b36bbc1c6d27 | 438 | writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps |
demayer | 1:b36bbc1c6d27 | 439 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz |
demayer | 1:b36bbc1c6d27 | 440 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g |
demayer | 1:b36bbc1c6d27 | 441 | |
demayer | 1:b36bbc1c6d27 | 442 | for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer |
demayer | 1:b36bbc1c6d27 | 443 | |
demayer | 1:b36bbc1c6d27 | 444 | readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array |
demayer | 1:b36bbc1c6d27 | 445 | aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value |
demayer | 1:b36bbc1c6d27 | 446 | aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; |
demayer | 1:b36bbc1c6d27 | 447 | aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; |
demayer | 1:b36bbc1c6d27 | 448 | |
demayer | 1:b36bbc1c6d27 | 449 | readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array |
demayer | 1:b36bbc1c6d27 | 450 | gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value |
demayer | 1:b36bbc1c6d27 | 451 | gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; |
demayer | 1:b36bbc1c6d27 | 452 | gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; |
demayer | 1:b36bbc1c6d27 | 453 | } |
demayer | 1:b36bbc1c6d27 | 454 | |
demayer | 1:b36bbc1c6d27 | 455 | for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings |
demayer | 1:b36bbc1c6d27 | 456 | aAvg[ii] /= 200; |
demayer | 1:b36bbc1c6d27 | 457 | gAvg[ii] /= 200; |
demayer | 1:b36bbc1c6d27 | 458 | } |
demayer | 1:b36bbc1c6d27 | 459 | |
demayer | 1:b36bbc1c6d27 | 460 | // Configure the accelerometer for self-test |
demayer | 1:b36bbc1c6d27 | 461 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g |
demayer | 1:b36bbc1c6d27 | 462 | writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s |
demayer | 1:b36bbc1c6d27 | 463 | wait(0.025); // Delay a while to let the device stabilize |
demayer | 1:b36bbc1c6d27 | 464 | |
demayer | 1:b36bbc1c6d27 | 465 | for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer |
demayer | 1:b36bbc1c6d27 | 466 | |
demayer | 1:b36bbc1c6d27 | 467 | readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array |
demayer | 1:b36bbc1c6d27 | 468 | aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value |
demayer | 1:b36bbc1c6d27 | 469 | aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; |
demayer | 1:b36bbc1c6d27 | 470 | aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; |
demayer | 1:b36bbc1c6d27 | 471 | |
demayer | 1:b36bbc1c6d27 | 472 | readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array |
demayer | 1:b36bbc1c6d27 | 473 | gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value |
demayer | 1:b36bbc1c6d27 | 474 | gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; |
demayer | 1:b36bbc1c6d27 | 475 | gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; |
demayer | 1:b36bbc1c6d27 | 476 | } |
demayer | 1:b36bbc1c6d27 | 477 | |
demayer | 1:b36bbc1c6d27 | 478 | for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings |
demayer | 1:b36bbc1c6d27 | 479 | aSTAvg[ii] /= 200; |
demayer | 1:b36bbc1c6d27 | 480 | gSTAvg[ii] /= 200; |
demayer | 1:b36bbc1c6d27 | 481 | } |
demayer | 1:b36bbc1c6d27 | 482 | |
demayer | 1:b36bbc1c6d27 | 483 | // Configure the gyro and accelerometer for normal operation |
demayer | 1:b36bbc1c6d27 | 484 | writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); |
demayer | 1:b36bbc1c6d27 | 485 | writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); |
demayer | 1:b36bbc1c6d27 | 486 | wait(0.025); // Delay a while to let the device stabilize |
demayer | 1:b36bbc1c6d27 | 487 | |
demayer | 1:b36bbc1c6d27 | 488 | // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg |
demayer | 1:b36bbc1c6d27 | 489 | selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results |
demayer | 1:b36bbc1c6d27 | 490 | selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results |
demayer | 1:b36bbc1c6d27 | 491 | selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results |
demayer | 1:b36bbc1c6d27 | 492 | selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results |
demayer | 1:b36bbc1c6d27 | 493 | selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results |
demayer | 1:b36bbc1c6d27 | 494 | selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results |
demayer | 1:b36bbc1c6d27 | 495 | |
demayer | 1:b36bbc1c6d27 | 496 | // Retrieve factory self-test value from self-test code reads |
demayer | 1:b36bbc1c6d27 | 497 | factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01, ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation |
demayer | 1:b36bbc1c6d27 | 498 | factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01, ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation |
demayer | 1:b36bbc1c6d27 | 499 | factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01, ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation |
demayer | 1:b36bbc1c6d27 | 500 | factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01, ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation |
demayer | 1:b36bbc1c6d27 | 501 | factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01, ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation |
demayer | 1:b36bbc1c6d27 | 502 | factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01, ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation |
demayer | 1:b36bbc1c6d27 | 503 | |
demayer | 1:b36bbc1c6d27 | 504 | // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response |
demayer | 1:b36bbc1c6d27 | 505 | // To get percent, must multiply by 100 |
demayer | 1:b36bbc1c6d27 | 506 | for (int i = 0; i < 3; i++) { |
demayer | 1:b36bbc1c6d27 | 507 | destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences |
demayer | 1:b36bbc1c6d27 | 508 | destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences |
demayer | 1:b36bbc1c6d27 | 509 | } |
demayer | 1:b36bbc1c6d27 | 510 | |
demayer | 1:b36bbc1c6d27 | 511 | } |
demayer | 1:b36bbc1c6d27 | 512 | |
demayer | 1:b36bbc1c6d27 | 513 | |
demayer | 1:b36bbc1c6d27 | 514 | |
demayer | 1:b36bbc1c6d27 | 515 | // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays" |
demayer | 1:b36bbc1c6d27 | 516 | // (see http://www.x-io.co.uk/category/open-source/ for examples and more details) |
demayer | 1:b36bbc1c6d27 | 517 | // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute |
demayer | 1:b36bbc1c6d27 | 518 | // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc. |
demayer | 1:b36bbc1c6d27 | 519 | // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms |
demayer | 1:b36bbc1c6d27 | 520 | // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz! |
demayer | 1:b36bbc1c6d27 | 521 | void MPU9250::MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) |
demayer | 1:b36bbc1c6d27 | 522 | { |
demayer | 1:b36bbc1c6d27 | 523 | float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability |
demayer | 1:b36bbc1c6d27 | 524 | float norm; |
demayer | 1:b36bbc1c6d27 | 525 | float hx, hy, _2bx, _2bz; |
demayer | 1:b36bbc1c6d27 | 526 | float s1, s2, s3, s4; |
demayer | 1:b36bbc1c6d27 | 527 | float qDot1, qDot2, qDot3, qDot4; |
demayer | 1:b36bbc1c6d27 | 528 | |
demayer | 1:b36bbc1c6d27 | 529 | // Auxiliary variables to avoid repeated arithmetic |
demayer | 1:b36bbc1c6d27 | 530 | float _2q1mx; |
demayer | 1:b36bbc1c6d27 | 531 | float _2q1my; |
demayer | 1:b36bbc1c6d27 | 532 | float _2q1mz; |
demayer | 1:b36bbc1c6d27 | 533 | float _2q2mx; |
demayer | 1:b36bbc1c6d27 | 534 | float _4bx; |
demayer | 1:b36bbc1c6d27 | 535 | float _4bz; |
demayer | 1:b36bbc1c6d27 | 536 | float _2q1 = 2.0f * q1; |
demayer | 1:b36bbc1c6d27 | 537 | float _2q2 = 2.0f * q2; |
demayer | 1:b36bbc1c6d27 | 538 | float _2q3 = 2.0f * q3; |
demayer | 1:b36bbc1c6d27 | 539 | float _2q4 = 2.0f * q4; |
demayer | 1:b36bbc1c6d27 | 540 | float _2q1q3 = 2.0f * q1 * q3; |
demayer | 1:b36bbc1c6d27 | 541 | float _2q3q4 = 2.0f * q3 * q4; |
demayer | 1:b36bbc1c6d27 | 542 | float q1q1 = q1 * q1; |
demayer | 1:b36bbc1c6d27 | 543 | float q1q2 = q1 * q2; |
demayer | 1:b36bbc1c6d27 | 544 | float q1q3 = q1 * q3; |
demayer | 1:b36bbc1c6d27 | 545 | float q1q4 = q1 * q4; |
demayer | 1:b36bbc1c6d27 | 546 | float q2q2 = q2 * q2; |
demayer | 1:b36bbc1c6d27 | 547 | float q2q3 = q2 * q3; |
demayer | 1:b36bbc1c6d27 | 548 | float q2q4 = q2 * q4; |
demayer | 1:b36bbc1c6d27 | 549 | float q3q3 = q3 * q3; |
demayer | 1:b36bbc1c6d27 | 550 | float q3q4 = q3 * q4; |
demayer | 1:b36bbc1c6d27 | 551 | float q4q4 = q4 * q4; |
demayer | 1:b36bbc1c6d27 | 552 | |
demayer | 1:b36bbc1c6d27 | 553 | // Normalise accelerometer measurement |
demayer | 1:b36bbc1c6d27 | 554 | norm = sqrt(ax * ax + ay * ay + az * az); |
demayer | 1:b36bbc1c6d27 | 555 | if (norm == 0.0f) return; // handle NaN |
demayer | 1:b36bbc1c6d27 | 556 | norm = 1.0f/norm; |
demayer | 1:b36bbc1c6d27 | 557 | ax *= norm; |
demayer | 1:b36bbc1c6d27 | 558 | ay *= norm; |
demayer | 1:b36bbc1c6d27 | 559 | az *= norm; |
demayer | 1:b36bbc1c6d27 | 560 | |
demayer | 1:b36bbc1c6d27 | 561 | // Normalise magnetometer measurement |
demayer | 1:b36bbc1c6d27 | 562 | norm = sqrt(mx * mx + my * my + mz * mz); |
demayer | 1:b36bbc1c6d27 | 563 | if (norm == 0.0f) return; // handle NaN |
demayer | 1:b36bbc1c6d27 | 564 | norm = 1.0f/norm; |
demayer | 1:b36bbc1c6d27 | 565 | mx *= norm; |
demayer | 1:b36bbc1c6d27 | 566 | my *= norm; |
demayer | 1:b36bbc1c6d27 | 567 | mz *= norm; |
demayer | 1:b36bbc1c6d27 | 568 | |
demayer | 1:b36bbc1c6d27 | 569 | // Reference direction of Earth's magnetic field |
demayer | 1:b36bbc1c6d27 | 570 | _2q1mx = 2.0f * q1 * mx; |
demayer | 1:b36bbc1c6d27 | 571 | _2q1my = 2.0f * q1 * my; |
demayer | 1:b36bbc1c6d27 | 572 | _2q1mz = 2.0f * q1 * mz; |
demayer | 1:b36bbc1c6d27 | 573 | _2q2mx = 2.0f * q2 * mx; |
demayer | 1:b36bbc1c6d27 | 574 | hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4; |
demayer | 1:b36bbc1c6d27 | 575 | hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4; |
demayer | 1:b36bbc1c6d27 | 576 | _2bx = sqrt(hx * hx + hy * hy); |
demayer | 1:b36bbc1c6d27 | 577 | _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4; |
demayer | 1:b36bbc1c6d27 | 578 | _4bx = 2.0f * _2bx; |
demayer | 1:b36bbc1c6d27 | 579 | _4bz = 2.0f * _2bz; |
demayer | 1:b36bbc1c6d27 | 580 | |
demayer | 1:b36bbc1c6d27 | 581 | // Gradient decent algorithm corrective step |
demayer | 1:b36bbc1c6d27 | 582 | s1 = -_2q3 * (2.0f * q2q4 - _2q1q3 - ax) + _2q2 * (2.0f * q1q2 + _2q3q4 - ay) - _2bz * q3 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q4 + _2bz * q2) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q3 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
demayer | 1:b36bbc1c6d27 | 583 | s2 = _2q4 * (2.0f * q2q4 - _2q1q3 - ax) + _2q1 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q2 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + _2bz * q4 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q3 + _2bz * q1) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q4 - _4bz * q2) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
demayer | 1:b36bbc1c6d27 | 584 | s3 = -_2q1 * (2.0f * q2q4 - _2q1q3 - ax) + _2q4 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q3 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + (-_4bx * q3 - _2bz * q1) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q2 + _2bz * q4) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q1 - _4bz * q3) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
demayer | 1:b36bbc1c6d27 | 585 | s4 = _2q2 * (2.0f * q2q4 - _2q1q3 - ax) + _2q3 * (2.0f * q1q2 + _2q3q4 - ay) + (-_4bx * q4 + _2bz * q2) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q1 + _2bz * q3) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q2 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |
demayer | 1:b36bbc1c6d27 | 586 | norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude |
demayer | 1:b36bbc1c6d27 | 587 | norm = 1.0f/norm; |
demayer | 1:b36bbc1c6d27 | 588 | s1 *= norm; |
demayer | 1:b36bbc1c6d27 | 589 | s2 *= norm; |
demayer | 1:b36bbc1c6d27 | 590 | s3 *= norm; |
demayer | 1:b36bbc1c6d27 | 591 | s4 *= norm; |
demayer | 1:b36bbc1c6d27 | 592 | |
demayer | 1:b36bbc1c6d27 | 593 | // Compute rate of change of quaternion |
demayer | 1:b36bbc1c6d27 | 594 | qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1; |
demayer | 1:b36bbc1c6d27 | 595 | qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2; |
demayer | 1:b36bbc1c6d27 | 596 | qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3; |
demayer | 1:b36bbc1c6d27 | 597 | qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4; |
demayer | 1:b36bbc1c6d27 | 598 | |
demayer | 1:b36bbc1c6d27 | 599 | // Integrate to yield quaternion |
demayer | 1:b36bbc1c6d27 | 600 | q1 += qDot1 * deltat; |
demayer | 1:b36bbc1c6d27 | 601 | q2 += qDot2 * deltat; |
demayer | 1:b36bbc1c6d27 | 602 | q3 += qDot3 * deltat; |
demayer | 1:b36bbc1c6d27 | 603 | q4 += qDot4 * deltat; |
demayer | 1:b36bbc1c6d27 | 604 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion |
demayer | 1:b36bbc1c6d27 | 605 | norm = 1.0f/norm; |
demayer | 1:b36bbc1c6d27 | 606 | q[0] = q1 * norm; |
demayer | 1:b36bbc1c6d27 | 607 | q[1] = q2 * norm; |
demayer | 1:b36bbc1c6d27 | 608 | q[2] = q3 * norm; |
demayer | 1:b36bbc1c6d27 | 609 | q[3] = q4 * norm; |
demayer | 1:b36bbc1c6d27 | 610 | |
demayer | 1:b36bbc1c6d27 | 611 | } |
demayer | 1:b36bbc1c6d27 | 612 | |
demayer | 1:b36bbc1c6d27 | 613 | |
demayer | 1:b36bbc1c6d27 | 614 | |
demayer | 1:b36bbc1c6d27 | 615 | // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and |
demayer | 1:b36bbc1c6d27 | 616 | // measured ones. |
demayer | 1:b36bbc1c6d27 | 617 | void MPU9250::MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) |
demayer | 1:b36bbc1c6d27 | 618 | { |
demayer | 1:b36bbc1c6d27 | 619 | float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability |
demayer | 1:b36bbc1c6d27 | 620 | float norm; |
demayer | 1:b36bbc1c6d27 | 621 | float hx, hy, bx, bz; |
demayer | 1:b36bbc1c6d27 | 622 | float vx, vy, vz, wx, wy, wz; |
demayer | 1:b36bbc1c6d27 | 623 | float ex, ey, ez; |
demayer | 1:b36bbc1c6d27 | 624 | float pa, pb, pc; |
demayer | 1:b36bbc1c6d27 | 625 | |
demayer | 1:b36bbc1c6d27 | 626 | // Auxiliary variables to avoid repeated arithmetic |
demayer | 1:b36bbc1c6d27 | 627 | float q1q1 = q1 * q1; |
demayer | 1:b36bbc1c6d27 | 628 | float q1q2 = q1 * q2; |
demayer | 1:b36bbc1c6d27 | 629 | float q1q3 = q1 * q3; |
demayer | 1:b36bbc1c6d27 | 630 | float q1q4 = q1 * q4; |
demayer | 1:b36bbc1c6d27 | 631 | float q2q2 = q2 * q2; |
demayer | 1:b36bbc1c6d27 | 632 | float q2q3 = q2 * q3; |
demayer | 1:b36bbc1c6d27 | 633 | float q2q4 = q2 * q4; |
demayer | 1:b36bbc1c6d27 | 634 | float q3q3 = q3 * q3; |
demayer | 1:b36bbc1c6d27 | 635 | float q3q4 = q3 * q4; |
demayer | 1:b36bbc1c6d27 | 636 | float q4q4 = q4 * q4; |
demayer | 1:b36bbc1c6d27 | 637 | |
demayer | 1:b36bbc1c6d27 | 638 | // Normalise accelerometer measurement |
demayer | 1:b36bbc1c6d27 | 639 | norm = sqrt(ax * ax + ay * ay + az * az); |
demayer | 1:b36bbc1c6d27 | 640 | if (norm == 0.0f) return; // handle NaN |
demayer | 1:b36bbc1c6d27 | 641 | norm = 1.0f / norm; // use reciprocal for division |
demayer | 1:b36bbc1c6d27 | 642 | ax *= norm; |
demayer | 1:b36bbc1c6d27 | 643 | ay *= norm; |
demayer | 1:b36bbc1c6d27 | 644 | az *= norm; |
demayer | 1:b36bbc1c6d27 | 645 | |
demayer | 1:b36bbc1c6d27 | 646 | // Normalise magnetometer measurement |
demayer | 1:b36bbc1c6d27 | 647 | norm = sqrt(mx * mx + my * my + mz * mz); |
demayer | 1:b36bbc1c6d27 | 648 | if (norm == 0.0f) return; // handle NaN |
demayer | 1:b36bbc1c6d27 | 649 | norm = 1.0f / norm; // use reciprocal for division |
demayer | 1:b36bbc1c6d27 | 650 | mx *= norm; |
demayer | 1:b36bbc1c6d27 | 651 | my *= norm; |
demayer | 1:b36bbc1c6d27 | 652 | mz *= norm; |
demayer | 1:b36bbc1c6d27 | 653 | |
demayer | 1:b36bbc1c6d27 | 654 | // Reference direction of Earth's magnetic field |
demayer | 1:b36bbc1c6d27 | 655 | hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3); |
demayer | 1:b36bbc1c6d27 | 656 | hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2); |
demayer | 1:b36bbc1c6d27 | 657 | bx = sqrt((hx * hx) + (hy * hy)); |
demayer | 1:b36bbc1c6d27 | 658 | bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3); |
demayer | 1:b36bbc1c6d27 | 659 | |
demayer | 1:b36bbc1c6d27 | 660 | // Estimated direction of gravity and magnetic field |
demayer | 1:b36bbc1c6d27 | 661 | vx = 2.0f * (q2q4 - q1q3); |
demayer | 1:b36bbc1c6d27 | 662 | vy = 2.0f * (q1q2 + q3q4); |
demayer | 1:b36bbc1c6d27 | 663 | vz = q1q1 - q2q2 - q3q3 + q4q4; |
demayer | 1:b36bbc1c6d27 | 664 | wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3); |
demayer | 1:b36bbc1c6d27 | 665 | wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4); |
demayer | 1:b36bbc1c6d27 | 666 | wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3); |
demayer | 1:b36bbc1c6d27 | 667 | |
demayer | 1:b36bbc1c6d27 | 668 | // Error is cross product between estimated direction and measured direction of gravity |
demayer | 1:b36bbc1c6d27 | 669 | ex = (ay * vz - az * vy) + (my * wz - mz * wy); |
demayer | 1:b36bbc1c6d27 | 670 | ey = (az * vx - ax * vz) + (mz * wx - mx * wz); |
demayer | 1:b36bbc1c6d27 | 671 | ez = (ax * vy - ay * vx) + (mx * wy - my * wx); |
demayer | 1:b36bbc1c6d27 | 672 | if (Ki > 0.0f) { |
demayer | 1:b36bbc1c6d27 | 673 | eInt[0] += ex; // accumulate integral error |
demayer | 1:b36bbc1c6d27 | 674 | eInt[1] += ey; |
demayer | 1:b36bbc1c6d27 | 675 | eInt[2] += ez; |
demayer | 1:b36bbc1c6d27 | 676 | } else { |
demayer | 1:b36bbc1c6d27 | 677 | eInt[0] = 0.0f; // prevent integral wind up |
demayer | 1:b36bbc1c6d27 | 678 | eInt[1] = 0.0f; |
demayer | 1:b36bbc1c6d27 | 679 | eInt[2] = 0.0f; |
demayer | 1:b36bbc1c6d27 | 680 | } |
demayer | 1:b36bbc1c6d27 | 681 | |
demayer | 1:b36bbc1c6d27 | 682 | // Apply feedback terms |
demayer | 1:b36bbc1c6d27 | 683 | gx = gx + Kp * ex + Ki * eInt[0]; |
demayer | 1:b36bbc1c6d27 | 684 | gy = gy + Kp * ey + Ki * eInt[1]; |
demayer | 1:b36bbc1c6d27 | 685 | gz = gz + Kp * ez + Ki * eInt[2]; |
demayer | 1:b36bbc1c6d27 | 686 | |
demayer | 1:b36bbc1c6d27 | 687 | // Integrate rate of change of quaternion |
demayer | 1:b36bbc1c6d27 | 688 | pa = q2; |
demayer | 1:b36bbc1c6d27 | 689 | pb = q3; |
demayer | 1:b36bbc1c6d27 | 690 | pc = q4; |
demayer | 1:b36bbc1c6d27 | 691 | q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat); |
demayer | 1:b36bbc1c6d27 | 692 | q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat); |
demayer | 1:b36bbc1c6d27 | 693 | q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat); |
demayer | 1:b36bbc1c6d27 | 694 | q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat); |
demayer | 1:b36bbc1c6d27 | 695 | |
demayer | 1:b36bbc1c6d27 | 696 | // Normalise quaternion |
demayer | 1:b36bbc1c6d27 | 697 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); |
demayer | 1:b36bbc1c6d27 | 698 | norm = 1.0f / norm; |
demayer | 1:b36bbc1c6d27 | 699 | q[0] = q1 * norm; |
demayer | 1:b36bbc1c6d27 | 700 | q[1] = q2 * norm; |
demayer | 1:b36bbc1c6d27 | 701 | q[2] = q3 * norm; |
demayer | 1:b36bbc1c6d27 | 702 | q[3] = q4 * norm; |
demayer | 1:b36bbc1c6d27 | 703 | |
demayer | 1:b36bbc1c6d27 | 704 | } |
demayer | 1:b36bbc1c6d27 | 705 | |
demayer | 1:b36bbc1c6d27 | 706 | // Integrates the acceleration to get the boards translative velocity |
demayer | 1:b36bbc1c6d27 | 707 | void MPU9250::velocityUpdate(float ax, float ay, float az) |
demayer | 1:b36bbc1c6d27 | 708 | { |
demayer | 1:b36bbc1c6d27 | 709 | // short name local variable for readability |
demayer | 1:b36bbc1c6d27 | 710 | |
demayer | 1:b36bbc1c6d27 | 711 | v_trans[0] = deltat*0.5*(a_old[0] + ax*GRAVITATION) + v_trans[0]; |
demayer | 1:b36bbc1c6d27 | 712 | v_trans[1] = deltat*0.5*(a_old[1] + ay*GRAVITATION) + v_trans[1]; |
demayer | 1:b36bbc1c6d27 | 713 | v_trans[2] = deltat*0.5*(a_old[2] + az*GRAVITATION + GRAVITATION) + v_trans[2]; |
demayer | 1:b36bbc1c6d27 | 714 | |
demayer | 1:b36bbc1c6d27 | 715 | a_old[0] = ax*GRAVITATION; |
demayer | 1:b36bbc1c6d27 | 716 | a_old[1] = ay*GRAVITATION; |
demayer | 1:b36bbc1c6d27 | 717 | a_old[2] = az*GRAVITATION; |
demayer | 1:b36bbc1c6d27 | 718 | } |
demayer | 1:b36bbc1c6d27 | 719 | |
demayer | 1:b36bbc1c6d27 | 720 | void MPU9250::readIMU() |
demayer | 1:b36bbc1c6d27 | 721 | { |
demayer | 1:b36bbc1c6d27 | 722 | // If intPin goes high, all data registers have new data |
demayer | 1:b36bbc1c6d27 | 723 | if(mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt |
demayer | 1:b36bbc1c6d27 | 724 | |
demayer | 1:b36bbc1c6d27 | 725 | mpu9250.readAccelData(accelCount); // Read the x/y/z adc values |
demayer | 1:b36bbc1c6d27 | 726 | // Now we'll calculate the accleration value into actual g's |
demayer | 1:b36bbc1c6d27 | 727 | ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set |
demayer | 1:b36bbc1c6d27 | 728 | ay = (float)accelCount[1]*aRes - accelBias[1]; |
demayer | 1:b36bbc1c6d27 | 729 | az = (float)accelCount[2]*aRes - accelBias[2]; |
demayer | 1:b36bbc1c6d27 | 730 | |
demayer | 1:b36bbc1c6d27 | 731 | mpu9250.readGyroData(gyroCount); // Read the x/y/z adc values |
demayer | 1:b36bbc1c6d27 | 732 | // Calculate the gyro value into actual degrees per second |
demayer | 1:b36bbc1c6d27 | 733 | gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set |
demayer | 1:b36bbc1c6d27 | 734 | gy = (float)gyroCount[1]*gRes - gyroBias[1]; |
demayer | 1:b36bbc1c6d27 | 735 | gz = (float)gyroCount[2]*gRes - gyroBias[2]; |
demayer | 1:b36bbc1c6d27 | 736 | |
demayer | 1:b36bbc1c6d27 | 737 | mpu9250.readMagData(magCount); // Read the x/y/z adc values |
demayer | 1:b36bbc1c6d27 | 738 | // Calculate the magnetometer values in milliGauss |
demayer | 1:b36bbc1c6d27 | 739 | // Include factory calibration per data sheet and user environmental corrections |
demayer | 1:b36bbc1c6d27 | 740 | mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]; // get actual magnetometer value, this depends on scale being set |
demayer | 1:b36bbc1c6d27 | 741 | my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1]; |
demayer | 1:b36bbc1c6d27 | 742 | mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2]; |
demayer | 1:b36bbc1c6d27 | 743 | } |
demayer | 1:b36bbc1c6d27 | 744 | |
demayer | 1:b36bbc1c6d27 | 745 | pc.printf("ax, ay, az, delta_t;%f;%f;%f;%f\n\r", ax, ay, az*GRAVITATION + GRAVITATION, deltat); |
demayer | 1:b36bbc1c6d27 | 746 | |
demayer | 1:b36bbc1c6d27 | 747 | Now = t.read_us(); |
demayer | 1:b36bbc1c6d27 | 748 | |
demayer | 1:b36bbc1c6d27 | 749 | deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update |
demayer | 1:b36bbc1c6d27 | 750 | lastUpdate = Now; |
demayer | 1:b36bbc1c6d27 | 751 | |
demayer | 1:b36bbc1c6d27 | 752 | sum += deltat; |
demayer | 1:b36bbc1c6d27 | 753 | sumCount++; |
demayer | 1:b36bbc1c6d27 | 754 | |
demayer | 1:b36bbc1c6d27 | 755 | |
demayer | 1:b36bbc1c6d27 | 756 | mpu9250.velocityUpdate(ax, ay, az); |
demayer | 1:b36bbc1c6d27 | 757 | |
demayer | 1:b36bbc1c6d27 | 758 | // Pass gyro rate as rad/s |
demayer | 1:b36bbc1c6d27 | 759 | mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz); |
demayer | 1:b36bbc1c6d27 | 760 | //mpu9250.MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz); |
demayer | 1:b36bbc1c6d27 | 761 | |
demayer | 1:b36bbc1c6d27 | 762 | // Serial print and/or display at 0.5 s rate independent of data rates |
demayer | 1:b36bbc1c6d27 | 763 | delt_t = t.read_ms() - _count; |
demayer | 1:b36bbc1c6d27 | 764 | |
demayer | 1:b36bbc1c6d27 | 765 | //----------------------------------------- |
demayer | 1:b36bbc1c6d27 | 766 | // Update displayed value |
demayer | 1:b36bbc1c6d27 | 767 | if (delt_t > SAMPLE_TIME) { |
demayer | 1:b36bbc1c6d27 | 768 | |
demayer | 1:b36bbc1c6d27 | 769 | |
demayer | 1:b36bbc1c6d27 | 770 | |
demayer | 1:b36bbc1c6d27 | 771 | //pc.printf("vx, vy, vz: %f %f %f\n\r", v_trans[0], v_trans[1], v_trans[2]); |
demayer | 1:b36bbc1c6d27 | 772 | |
demayer | 1:b36bbc1c6d27 | 773 | |
demayer | 1:b36bbc1c6d27 | 774 | yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]); |
demayer | 1:b36bbc1c6d27 | 775 | pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2])); |
demayer | 1:b36bbc1c6d27 | 776 | roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]); |
demayer | 1:b36bbc1c6d27 | 777 | pitch *= 180.0f / PI; |
demayer | 1:b36bbc1c6d27 | 778 | yaw *= 180.0f / PI; |
demayer | 1:b36bbc1c6d27 | 779 | yaw -= 2.93f; // Declination at 8572 Berg TG: +2° 56' |
demayer | 1:b36bbc1c6d27 | 780 | roll *= 180.0f / PI; |
demayer | 1:b36bbc1c6d27 | 781 | |
demayer | 1:b36bbc1c6d27 | 782 | myData.ax = yaw; |
demayer | 1:b36bbc1c6d27 | 783 | myData.ay = pitch; |
demayer | 1:b36bbc1c6d27 | 784 | myData.az = roll; |
demayer | 1:b36bbc1c6d27 | 785 | |
demayer | 1:b36bbc1c6d27 | 786 | |
demayer | 1:b36bbc1c6d27 | 787 | myled= !myled; |
demayer | 1:b36bbc1c6d27 | 788 | _count = t.read_ms(); |
demayer | 1:b36bbc1c6d27 | 789 | |
demayer | 1:b36bbc1c6d27 | 790 | if(_count > 1<<21) { |
demayer | 1:b36bbc1c6d27 | 791 | t.start(); // start the timer over again if ~30 minutes has passed |
demayer | 1:b36bbc1c6d27 | 792 | _count = 0; |
demayer | 1:b36bbc1c6d27 | 793 | deltat= 0; |
demayer | 1:b36bbc1c6d27 | 794 | lastUpdate = t.read_us(); |
demayer | 1:b36bbc1c6d27 | 795 | } |
demayer | 1:b36bbc1c6d27 | 796 | sum = 0; |
demayer | 1:b36bbc1c6d27 | 797 | sumCount = 0; |
demayer | 1:b36bbc1c6d27 | 798 | } |
demayer | 1:b36bbc1c6d27 | 799 | } |
demayer | 1:b36bbc1c6d27 | 800 | |
demayer | 1:b36bbc1c6d27 | 801 | |
demayer | 1:b36bbc1c6d27 | 802 | void MPU9250::imuSetup() |
demayer | 1:b36bbc1c6d27 | 803 | { |
demayer | 1:b36bbc1c6d27 | 804 | //Set up I2C |
demayer | 1:b36bbc1c6d27 | 805 | i2c.frequency(400000); // use fast (400 kHz) I2C |
demayer | 1:b36bbc1c6d27 | 806 | |
demayer | 1:b36bbc1c6d27 | 807 | pc.printf("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock); |
demayer | 1:b36bbc1c6d27 | 808 | |
demayer | 1:b36bbc1c6d27 | 809 | t.start(); |
demayer | 1:b36bbc1c6d27 | 810 | // lcd.setBrightness(0.05); |
demayer | 1:b36bbc1c6d27 | 811 | |
demayer | 1:b36bbc1c6d27 | 812 | |
demayer | 1:b36bbc1c6d27 | 813 | // Read the WHO_AM_I register, this is a good test of communication |
demayer | 1:b36bbc1c6d27 | 814 | uint8_t whoami = mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250 |
demayer | 1:b36bbc1c6d27 | 815 | pc.printf("I AM 0x%x\n\r", whoami); |
demayer | 1:b36bbc1c6d27 | 816 | pc.printf("I SHOULD BE 0x71\n\r"); |
demayer | 1:b36bbc1c6d27 | 817 | |
demayer | 1:b36bbc1c6d27 | 818 | if (whoami == 0x71) { // WHO_AM_I should always be 0x68 |
demayer | 1:b36bbc1c6d27 | 819 | pc.printf("MPU9250 WHO_AM_I is 0x%x\n\r", whoami); |
demayer | 1:b36bbc1c6d27 | 820 | pc.printf("MPU9250 is online...\n\r"); |
demayer | 1:b36bbc1c6d27 | 821 | sprintf(buffer, "0x%x", whoami); |
demayer | 1:b36bbc1c6d27 | 822 | wait(1); |
demayer | 1:b36bbc1c6d27 | 823 | |
demayer | 1:b36bbc1c6d27 | 824 | mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration |
demayer | 1:b36bbc1c6d27 | 825 | mpu9250.MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values |
demayer | 1:b36bbc1c6d27 | 826 | pc.printf("x-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[0]); |
demayer | 1:b36bbc1c6d27 | 827 | pc.printf("y-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[1]); |
demayer | 1:b36bbc1c6d27 | 828 | pc.printf("z-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[2]); |
demayer | 1:b36bbc1c6d27 | 829 | pc.printf("x-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[3]); |
demayer | 1:b36bbc1c6d27 | 830 | pc.printf("y-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[4]); |
demayer | 1:b36bbc1c6d27 | 831 | pc.printf("z-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[5]); |
demayer | 1:b36bbc1c6d27 | 832 | mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers |
demayer | 1:b36bbc1c6d27 | 833 | pc.printf("x gyro bias = %f\n\r", gyroBias[0]); |
demayer | 1:b36bbc1c6d27 | 834 | pc.printf("y gyro bias = %f\n\r", gyroBias[1]); |
demayer | 1:b36bbc1c6d27 | 835 | pc.printf("z gyro bias = %f\n\r", gyroBias[2]); |
demayer | 1:b36bbc1c6d27 | 836 | pc.printf("x accel bias = %f\n\r", accelBias[0]); |
demayer | 1:b36bbc1c6d27 | 837 | pc.printf("y accel bias = %f\n\r", accelBias[1]); |
demayer | 1:b36bbc1c6d27 | 838 | pc.printf("z accel bias = %f\n\r", accelBias[2]); |
demayer | 1:b36bbc1c6d27 | 839 | wait(2); |
demayer | 1:b36bbc1c6d27 | 840 | mpu9250.initMPU9250(); |
demayer | 1:b36bbc1c6d27 | 841 | pc.printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature |
demayer | 1:b36bbc1c6d27 | 842 | mpu9250.initAK8963(magCalibration); |
demayer | 1:b36bbc1c6d27 | 843 | pc.printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer |
demayer | 1:b36bbc1c6d27 | 844 | pc.printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale)); |
demayer | 1:b36bbc1c6d27 | 845 | pc.printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale)); |
demayer | 1:b36bbc1c6d27 | 846 | if(Mscale == 0) pc.printf("Magnetometer resolution = 14 bits\n\r"); |
demayer | 1:b36bbc1c6d27 | 847 | if(Mscale == 1) pc.printf("Magnetometer resolution = 16 bits\n\r"); |
demayer | 1:b36bbc1c6d27 | 848 | if(Mmode == 2) pc.printf("Magnetometer ODR = 8 Hz\n\r"); |
demayer | 1:b36bbc1c6d27 | 849 | if(Mmode == 6) pc.printf("Magnetometer ODR = 100 Hz\n\r"); |
demayer | 1:b36bbc1c6d27 | 850 | wait(1); |
demayer | 1:b36bbc1c6d27 | 851 | } else { |
demayer | 1:b36bbc1c6d27 | 852 | pc.printf("Could not connect to MPU9250: \n\r"); |
demayer | 1:b36bbc1c6d27 | 853 | pc.printf("%#x \n", whoami); |
demayer | 1:b36bbc1c6d27 | 854 | sprintf(buffer, "WHO_AM_I 0x%x", whoami); |
demayer | 1:b36bbc1c6d27 | 855 | |
demayer | 1:b36bbc1c6d27 | 856 | while(1) { |
demayer | 1:b36bbc1c6d27 | 857 | // Loop forever if communication doesn't happen |
demayer | 1:b36bbc1c6d27 | 858 | pc.printf("no IMU detected (verify if it's plugged in)\n\r"); |
demayer | 1:b36bbc1c6d27 | 859 | } |
demayer | 1:b36bbc1c6d27 | 860 | } |
demayer | 1:b36bbc1c6d27 | 861 | |
demayer | 1:b36bbc1c6d27 | 862 | mpu9250.getAres(); // Get accelerometer sensitivity |
demayer | 1:b36bbc1c6d27 | 863 | mpu9250.getGres(); // Get gyro sensitivity |
demayer | 1:b36bbc1c6d27 | 864 | mpu9250.getMres(); // Get magnetometer sensitivity |
demayer | 1:b36bbc1c6d27 | 865 | pc.printf("Accelerometer sensitivity is %f LSB/g \n\r", 1.0f/aRes); |
demayer | 1:b36bbc1c6d27 | 866 | pc.printf("Gyroscope sensitivity is %f LSB/deg/s \n\r", 1.0f/gRes); |
demayer | 1:b36bbc1c6d27 | 867 | pc.printf("Magnetometer sensitivity is %f LSB/G \n\r", 1.0f/mRes); |
demayer | 1:b36bbc1c6d27 | 868 | magbias[0] = +470.; // User environmental x-axis correction in milliGauss, should be automatically calculated |
demayer | 1:b36bbc1c6d27 | 869 | magbias[1] = +120.; // User environmental x-axis correction in milliGauss |
demayer | 1:b36bbc1c6d27 | 870 | magbias[2] = +125.; // User environmental x-axis correction in milliGauss |
demayer | 1:b36bbc1c6d27 | 871 | } |
demayer | 1:b36bbc1c6d27 | 872 | |
demayer | 1:b36bbc1c6d27 | 873 | accData_t MPU9250::getVelocityFromIMU(){ |
demayer | 1:b36bbc1c6d27 | 874 | readIMU(); |
demayer | 1:b36bbc1c6d27 | 875 | |
demayer | 1:b36bbc1c6d27 | 876 | return myData; |
demayer | 1:b36bbc1c6d27 | 877 | } |