OX / Mbed 2 deprecated Ox_ver_function

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Dependencies:   mbed

MPU9250.h@2:ce3ee4bc8cf7, 2016-12-06 (annotated)

Committer:
siwakon
Date:
Tue Dec 06 12:19:49 2016 +0000
Revision:
2:ce3ee4bc8cf7
Parent:
0:a291977ec0b1 
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arthicha 0:a291977ec0b1 1 #ifndef MPU9250_H
arthicha 0:a291977ec0b1 2 #define MPU9250_H
arthicha 0:a291977ec0b1 3
arthicha 0:a291977ec0b1 4 #include "mbed.h"
arthicha 0:a291977ec0b1 5 #include "math.h"
arthicha 0:a291977ec0b1 6
arthicha 0:a291977ec0b1 7 // See also MPU-9250 Register Map and Descriptions, Revision 4.0, RM-MPU-9250A-00, Rev. 1.4, 9/9/2013 for registers not listed in
arthicha 0:a291977ec0b1 8 // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map
arthicha 0:a291977ec0b1 9 //
arthicha 0:a291977ec0b1 10 //Magnetometer Registers
arthicha 0:a291977ec0b1 11 #define AK8963_ADDRESS 0x0C<<1
arthicha 0:a291977ec0b1 12 #define WHO_AM_I_AK8963 0x00 // should return 0x48
arthicha 0:a291977ec0b1 13 #define INFO 0x01
arthicha 0:a291977ec0b1 14 #define AK8963_ST1 0x02 // data ready status bit 0
arthicha 0:a291977ec0b1 15 #define AK8963_XOUT_L 0x03 // data
arthicha 0:a291977ec0b1 16 #define AK8963_XOUT_H 0x04
arthicha 0:a291977ec0b1 17 #define AK8963_YOUT_L 0x05
arthicha 0:a291977ec0b1 18 #define AK8963_YOUT_H 0x06
arthicha 0:a291977ec0b1 19 #define AK8963_ZOUT_L 0x07
arthicha 0:a291977ec0b1 20 #define AK8963_ZOUT_H 0x08
arthicha 0:a291977ec0b1 21 #define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status bit 2
arthicha 0:a291977ec0b1 22 #define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001), self-test (1000) and Fuse ROM (1111) modes on bits 3:0
arthicha 0:a291977ec0b1 23 #define AK8963_ASTC 0x0C // Self test control
arthicha 0:a291977ec0b1 24 #define AK8963_I2CDIS 0x0F // I2C disable
arthicha 0:a291977ec0b1 25 #define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value
arthicha 0:a291977ec0b1 26 #define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value
arthicha 0:a291977ec0b1 27 #define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value
arthicha 0:a291977ec0b1 28
arthicha 0:a291977ec0b1 29 #define SELF_TEST_X_GYRO 0x00
arthicha 0:a291977ec0b1 30 #define SELF_TEST_Y_GYRO 0x01
arthicha 0:a291977ec0b1 31 #define SELF_TEST_Z_GYRO 0x02
arthicha 0:a291977ec0b1 32
arthicha 0:a291977ec0b1 33 /*#define X_FINE_GAIN 0x03 // [7:0] fine gain
arthicha 0:a291977ec0b1 34 #define Y_FINE_GAIN 0x04
arthicha 0:a291977ec0b1 35 #define Z_FINE_GAIN 0x05
arthicha 0:a291977ec0b1 36 #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer
arthicha 0:a291977ec0b1 37 #define XA_OFFSET_L_TC 0x07
arthicha 0:a291977ec0b1 38 #define YA_OFFSET_H 0x08
arthicha 0:a291977ec0b1 39 #define YA_OFFSET_L_TC 0x09
arthicha 0:a291977ec0b1 40 #define ZA_OFFSET_H 0x0A
arthicha 0:a291977ec0b1 41 #define ZA_OFFSET_L_TC 0x0B */
arthicha 0:a291977ec0b1 42
arthicha 0:a291977ec0b1 43 #define SELF_TEST_X_ACCEL 0x0D
arthicha 0:a291977ec0b1 44 #define SELF_TEST_Y_ACCEL 0x0E
arthicha 0:a291977ec0b1 45 #define SELF_TEST_Z_ACCEL 0x0F
arthicha 0:a291977ec0b1 46
arthicha 0:a291977ec0b1 47 #define SELF_TEST_A 0x10
arthicha 0:a291977ec0b1 48
arthicha 0:a291977ec0b1 49 #define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope
arthicha 0:a291977ec0b1 50 #define XG_OFFSET_L 0x14
arthicha 0:a291977ec0b1 51 #define YG_OFFSET_H 0x15
arthicha 0:a291977ec0b1 52 #define YG_OFFSET_L 0x16
arthicha 0:a291977ec0b1 53 #define ZG_OFFSET_H 0x17
arthicha 0:a291977ec0b1 54 #define ZG_OFFSET_L 0x18
arthicha 0:a291977ec0b1 55 #define SMPLRT_DIV 0x19
arthicha 0:a291977ec0b1 56 #define CONFIG 0x1A
arthicha 0:a291977ec0b1 57 #define GYRO_CONFIG 0x1B
arthicha 0:a291977ec0b1 58 #define ACCEL_CONFIG 0x1C
arthicha 0:a291977ec0b1 59 #define ACCEL_CONFIG2 0x1D
arthicha 0:a291977ec0b1 60 #define LP_ACCEL_ODR 0x1E
arthicha 0:a291977ec0b1 61 #define WOM_THR 0x1F
arthicha 0:a291977ec0b1 62
arthicha 0:a291977ec0b1 63 #define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms
arthicha 0:a291977ec0b1 64 #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]
arthicha 0:a291977ec0b1 65 #define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms
arthicha 0:a291977ec0b1 66
arthicha 0:a291977ec0b1 67 #define FIFO_EN 0x23
arthicha 0:a291977ec0b1 68 #define I2C_MST_CTRL 0x24
arthicha 0:a291977ec0b1 69 #define I2C_SLV0_ADDR 0x25
arthicha 0:a291977ec0b1 70 #define I2C_SLV0_REG 0x26
arthicha 0:a291977ec0b1 71 #define I2C_SLV0_CTRL 0x27
arthicha 0:a291977ec0b1 72 #define I2C_SLV1_ADDR 0x28
arthicha 0:a291977ec0b1 73 #define I2C_SLV1_REG 0x29
arthicha 0:a291977ec0b1 74 #define I2C_SLV1_CTRL 0x2A
arthicha 0:a291977ec0b1 75 #define I2C_SLV2_ADDR 0x2B
arthicha 0:a291977ec0b1 76 #define I2C_SLV2_REG 0x2C
arthicha 0:a291977ec0b1 77 #define I2C_SLV2_CTRL 0x2D
arthicha 0:a291977ec0b1 78 #define I2C_SLV3_ADDR 0x2E
arthicha 0:a291977ec0b1 79 #define I2C_SLV3_REG 0x2F
arthicha 0:a291977ec0b1 80 #define I2C_SLV3_CTRL 0x30
arthicha 0:a291977ec0b1 81 #define I2C_SLV4_ADDR 0x31
arthicha 0:a291977ec0b1 82 #define I2C_SLV4_REG 0x32
arthicha 0:a291977ec0b1 83 #define I2C_SLV4_DO 0x33
arthicha 0:a291977ec0b1 84 #define I2C_SLV4_CTRL 0x34
arthicha 0:a291977ec0b1 85 #define I2C_SLV4_DI 0x35
arthicha 0:a291977ec0b1 86 #define I2C_MST_STATUS 0x36
arthicha 0:a291977ec0b1 87 #define INT_PIN_CFG 0x37
arthicha 0:a291977ec0b1 88 #define INT_ENABLE 0x38
arthicha 0:a291977ec0b1 89 #define DMP_INT_STATUS 0x39 // Check DMP interrupt
arthicha 0:a291977ec0b1 90 #define INT_STATUS 0x3A
arthicha 0:a291977ec0b1 91 #define ACCEL_XOUT_H 0x3B
arthicha 0:a291977ec0b1 92 #define ACCEL_XOUT_L 0x3C
arthicha 0:a291977ec0b1 93 #define ACCEL_YOUT_H 0x3D
arthicha 0:a291977ec0b1 94 #define ACCEL_YOUT_L 0x3E
arthicha 0:a291977ec0b1 95 #define ACCEL_ZOUT_H 0x3F
arthicha 0:a291977ec0b1 96 #define ACCEL_ZOUT_L 0x40
arthicha 0:a291977ec0b1 97 #define TEMP_OUT_H 0x41
arthicha 0:a291977ec0b1 98 #define TEMP_OUT_L 0x42
arthicha 0:a291977ec0b1 99 #define GYRO_XOUT_H 0x43
arthicha 0:a291977ec0b1 100 #define GYRO_XOUT_L 0x44
arthicha 0:a291977ec0b1 101 #define GYRO_YOUT_H 0x45
arthicha 0:a291977ec0b1 102 #define GYRO_YOUT_L 0x46
arthicha 0:a291977ec0b1 103 #define GYRO_ZOUT_H 0x47
arthicha 0:a291977ec0b1 104 #define GYRO_ZOUT_L 0x48
arthicha 0:a291977ec0b1 105 #define EXT_SENS_DATA_00 0x49
arthicha 0:a291977ec0b1 106 #define EXT_SENS_DATA_01 0x4A
arthicha 0:a291977ec0b1 107 #define EXT_SENS_DATA_02 0x4B
arthicha 0:a291977ec0b1 108 #define EXT_SENS_DATA_03 0x4C
arthicha 0:a291977ec0b1 109 #define EXT_SENS_DATA_04 0x4D
arthicha 0:a291977ec0b1 110 #define EXT_SENS_DATA_05 0x4E
arthicha 0:a291977ec0b1 111 #define EXT_SENS_DATA_06 0x4F
arthicha 0:a291977ec0b1 112 #define EXT_SENS_DATA_07 0x50
arthicha 0:a291977ec0b1 113 #define EXT_SENS_DATA_08 0x51
arthicha 0:a291977ec0b1 114 #define EXT_SENS_DATA_09 0x52
arthicha 0:a291977ec0b1 115 #define EXT_SENS_DATA_10 0x53
arthicha 0:a291977ec0b1 116 #define EXT_SENS_DATA_11 0x54
arthicha 0:a291977ec0b1 117 #define EXT_SENS_DATA_12 0x55
arthicha 0:a291977ec0b1 118 #define EXT_SENS_DATA_13 0x56
arthicha 0:a291977ec0b1 119 #define EXT_SENS_DATA_14 0x57
arthicha 0:a291977ec0b1 120 #define EXT_SENS_DATA_15 0x58
arthicha 0:a291977ec0b1 121 #define EXT_SENS_DATA_16 0x59
arthicha 0:a291977ec0b1 122 #define EXT_SENS_DATA_17 0x5A
arthicha 0:a291977ec0b1 123 #define EXT_SENS_DATA_18 0x5B
arthicha 0:a291977ec0b1 124 #define EXT_SENS_DATA_19 0x5C
arthicha 0:a291977ec0b1 125 #define EXT_SENS_DATA_20 0x5D
arthicha 0:a291977ec0b1 126 #define EXT_SENS_DATA_21 0x5E
arthicha 0:a291977ec0b1 127 #define EXT_SENS_DATA_22 0x5F
arthicha 0:a291977ec0b1 128 #define EXT_SENS_DATA_23 0x60
arthicha 0:a291977ec0b1 129 #define MOT_DETECT_STATUS 0x61
arthicha 0:a291977ec0b1 130 #define I2C_SLV0_DO 0x63
arthicha 0:a291977ec0b1 131 #define I2C_SLV1_DO 0x64
arthicha 0:a291977ec0b1 132 #define I2C_SLV2_DO 0x65
arthicha 0:a291977ec0b1 133 #define I2C_SLV3_DO 0x66
arthicha 0:a291977ec0b1 134 #define I2C_MST_DELAY_CTRL 0x67
arthicha 0:a291977ec0b1 135 #define SIGNAL_PATH_RESET 0x68
arthicha 0:a291977ec0b1 136 #define MOT_DETECT_CTRL 0x69
arthicha 0:a291977ec0b1 137 #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP
arthicha 0:a291977ec0b1 138 #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode
arthicha 0:a291977ec0b1 139 #define PWR_MGMT_2 0x6C
arthicha 0:a291977ec0b1 140 #define DMP_BANK 0x6D // Activates a specific bank in the DMP
arthicha 0:a291977ec0b1 141 #define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank
arthicha 0:a291977ec0b1 142 #define DMP_REG 0x6F // Register in DMP from which to read or to which to write
arthicha 0:a291977ec0b1 143 #define DMP_REG_1 0x70
arthicha 0:a291977ec0b1 144 #define DMP_REG_2 0x71
arthicha 0:a291977ec0b1 145 #define FIFO_COUNTH 0x72
arthicha 0:a291977ec0b1 146 #define FIFO_COUNTL 0x73
arthicha 0:a291977ec0b1 147 #define FIFO_R_W 0x74
arthicha 0:a291977ec0b1 148 #define WHO_AM_I_MPU9250 0x75 // Should return 0x71
arthicha 0:a291977ec0b1 149 #define XA_OFFSET_H 0x77
arthicha 0:a291977ec0b1 150 #define XA_OFFSET_L 0x78
arthicha 0:a291977ec0b1 151 #define YA_OFFSET_H 0x7A
arthicha 0:a291977ec0b1 152 #define YA_OFFSET_L 0x7B
arthicha 0:a291977ec0b1 153 #define ZA_OFFSET_H 0x7D
arthicha 0:a291977ec0b1 154 #define ZA_OFFSET_L 0x7E
arthicha 0:a291977ec0b1 155
arthicha 0:a291977ec0b1 156 // Using the MSENSR-9250 breakout board, ADO is set to 0
arthicha 0:a291977ec0b1 157 // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1
arthicha 0:a291977ec0b1 158 //mbed uses the eight-bit device address, so shift seven-bit addresses left by one!
arthicha 0:a291977ec0b1 159 #define ADO 0
arthicha 0:a291977ec0b1 160 #if ADO
arthicha 0:a291977ec0b1 161 #define MPU9250_ADDRESS 0x69<<1 // Device address when ADO = 1
arthicha 0:a291977ec0b1 162 #else
arthicha 0:a291977ec0b1 163 #define MPU9250_ADDRESS 0x68<<1 // Device address when ADO = 0
arthicha 0:a291977ec0b1 164 #endif
arthicha 0:a291977ec0b1 165
arthicha 0:a291977ec0b1 166 // Set initial input parameters
arthicha 0:a291977ec0b1 167 enum Ascale {
arthicha 0:a291977ec0b1 168 AFS_2G = 0,
arthicha 0:a291977ec0b1 169 AFS_4G,
arthicha 0:a291977ec0b1 170 AFS_8G,
arthicha 0:a291977ec0b1 171 AFS_16G
arthicha 0:a291977ec0b1 172 };
arthicha 0:a291977ec0b1 173
arthicha 0:a291977ec0b1 174 enum Gscale {
arthicha 0:a291977ec0b1 175 GFS_250DPS = 0,
arthicha 0:a291977ec0b1 176 GFS_500DPS,
arthicha 0:a291977ec0b1 177 GFS_1000DPS,
arthicha 0:a291977ec0b1 178 GFS_2000DPS
arthicha 0:a291977ec0b1 179 };
arthicha 0:a291977ec0b1 180
arthicha 0:a291977ec0b1 181 enum Mscale {
arthicha 0:a291977ec0b1 182 MFS_14BITS = 0, // 0.6 mG per LSB
arthicha 0:a291977ec0b1 183 MFS_16BITS // 0.15 mG per LSB
arthicha 0:a291977ec0b1 184 };
arthicha 0:a291977ec0b1 185
arthicha 0:a291977ec0b1 186 uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G
arthicha 0:a291977ec0b1 187 uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS
arthicha 0:a291977ec0b1 188 uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution
arthicha 0:a291977ec0b1 189 uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR
arthicha 0:a291977ec0b1 190 float aRes, gRes, mRes; // scale resolutions per LSB for the sensors
arthicha 0:a291977ec0b1 191
arthicha 0:a291977ec0b1 192 //Set up I2C, (SDA,SCL)
arthicha 0:a291977ec0b1 193 I2C i2c(I2C_SDA, I2C_SCL);
arthicha 0:a291977ec0b1 194
arthicha 0:a291977ec0b1 195 DigitalOut myled(LED1);
arthicha 0:a291977ec0b1 196
arthicha 0:a291977ec0b1 197 // Pin definitions
arthicha 0:a291977ec0b1 198 int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins
arthicha 0:a291977ec0b1 199
arthicha 0:a291977ec0b1 200 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
arthicha 0:a291977ec0b1 201 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
arthicha 0:a291977ec0b1 202 int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output
arthicha 0:a291977ec0b1 203 float magCalibration[3] = {0, 0, 0}, magbias[3] = {0, 0, 0}; // Factory mag calibration and mag bias
arthicha 0:a291977ec0b1 204 float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer
arthicha 0:a291977ec0b1 205 float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
arthicha 0:a291977ec0b1 206 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
arthicha 0:a291977ec0b1 207 float temperature;
arthicha 0:a291977ec0b1 208 float SelfTest[6];
arthicha 0:a291977ec0b1 209
arthicha 0:a291977ec0b1 210 int delt_t = 0; // used to control display output rate
arthicha 0:a291977ec0b1 211 int count = 0; // used to control display output rate
arthicha 0:a291977ec0b1 212
arthicha 0:a291977ec0b1 213 // parameters for 6 DoF sensor fusion calculations
arthicha 0:a291977ec0b1 214 float PI = 3.14159265358979323846f;
arthicha 0:a291977ec0b1 215 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
arthicha 0:a291977ec0b1 216 float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
arthicha 0:a291977ec0b1 217 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
arthicha 0:a291977ec0b1 218 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
arthicha 0:a291977ec0b1 219 #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
arthicha 0:a291977ec0b1 220 #define Ki 0.0f
arthicha 0:a291977ec0b1 221
arthicha 0:a291977ec0b1 222 float pitch, yaw, roll;
arthicha 0:a291977ec0b1 223 float deltat = 0.0f; // integration interval for both filter schemes
arthicha 0:a291977ec0b1 224 int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval
arthicha 0:a291977ec0b1 225 float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion
arthicha 0:a291977ec0b1 226 float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method
arthicha 0:a291977ec0b1 227
arthicha 0:a291977ec0b1 228 class MPU9250 {
arthicha 0:a291977ec0b1 229
arthicha 0:a291977ec0b1 230 protected:
arthicha 0:a291977ec0b1 231
arthicha 0:a291977ec0b1 232 public:
arthicha 0:a291977ec0b1 233 //===================================================================================================================
arthicha 0:a291977ec0b1 234 //====== Set of useful function to access acceleratio, gyroscope, and temperature data
arthicha 0:a291977ec0b1 235 //===================================================================================================================
arthicha 0:a291977ec0b1 236
arthicha 0:a291977ec0b1 237 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
arthicha 0:a291977ec0b1 238 {
arthicha 0:a291977ec0b1 239 char data_write[2];
arthicha 0:a291977ec0b1 240 data_write[0] = subAddress;
arthicha 0:a291977ec0b1 241 data_write[1] = data;
arthicha 0:a291977ec0b1 242 i2c.write(address, data_write, 2, 0);
arthicha 0:a291977ec0b1 243 }
arthicha 0:a291977ec0b1 244
arthicha 0:a291977ec0b1 245 char readByte(uint8_t address, uint8_t subAddress)
arthicha 0:a291977ec0b1 246 {
arthicha 0:a291977ec0b1 247 char data[1]; // `data` will store the register data
arthicha 0:a291977ec0b1 248 char data_write[1];
arthicha 0:a291977ec0b1 249 data_write[0] = subAddress;
arthicha 0:a291977ec0b1 250 i2c.write(address, data_write, 1, 1); // no stop
siwakon 2:ce3ee4bc8cf7 251 i2c.read(address, data, 1, 0);
arthicha 0:a291977ec0b1 252 return data[0];
arthicha 0:a291977ec0b1 253 }
arthicha 0:a291977ec0b1 254
arthicha 0:a291977ec0b1 255 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
arthicha 0:a291977ec0b1 256 {
arthicha 0:a291977ec0b1 257 char data[14];
arthicha 0:a291977ec0b1 258 char data_write[1];
arthicha 0:a291977ec0b1 259 data_write[0] = subAddress;
arthicha 0:a291977ec0b1 260 i2c.write(address, data_write, 1, 1); // no stop
arthicha 0:a291977ec0b1 261 i2c.read(address, data, count, 0);
arthicha 0:a291977ec0b1 262 for(int ii = 0; ii < count; ii++) {
arthicha 0:a291977ec0b1 263 dest[ii] = data[ii];
arthicha 0:a291977ec0b1 264 }
arthicha 0:a291977ec0b1 265 }
arthicha 0:a291977ec0b1 266
arthicha 0:a291977ec0b1 267
arthicha 0:a291977ec0b1 268 void getMres() {
arthicha 0:a291977ec0b1 269 switch (Mscale)
arthicha 0:a291977ec0b1 270 {
arthicha 0:a291977ec0b1 271 // Possible magnetometer scales (and their register bit settings) are:
arthicha 0:a291977ec0b1 272 // 14 bit resolution (0) and 16 bit resolution (1)
arthicha 0:a291977ec0b1 273 case MFS_14BITS:
arthicha 0:a291977ec0b1 274 mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss
arthicha 0:a291977ec0b1 275 break;
arthicha 0:a291977ec0b1 276 case MFS_16BITS:
arthicha 0:a291977ec0b1 277 mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss
arthicha 0:a291977ec0b1 278 break;
arthicha 0:a291977ec0b1 279 }
arthicha 0:a291977ec0b1 280 }
arthicha 0:a291977ec0b1 281
arthicha 0:a291977ec0b1 282
arthicha 0:a291977ec0b1 283 void getGres() {
arthicha 0:a291977ec0b1 284 switch (Gscale)
arthicha 0:a291977ec0b1 285 {
arthicha 0:a291977ec0b1 286 // Possible gyro scales (and their register bit settings) are:
arthicha 0:a291977ec0b1 287 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
arthicha 0:a291977ec0b1 288 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
arthicha 0:a291977ec0b1 289 case GFS_250DPS:
arthicha 0:a291977ec0b1 290 gRes = 250.0/32768.0;
arthicha 0:a291977ec0b1 291 break;
arthicha 0:a291977ec0b1 292 case GFS_500DPS:
arthicha 0:a291977ec0b1 293 gRes = 500.0/32768.0;
arthicha 0:a291977ec0b1 294 break;
arthicha 0:a291977ec0b1 295 case GFS_1000DPS:
arthicha 0:a291977ec0b1 296 gRes = 1000.0/32768.0;
arthicha 0:a291977ec0b1 297 break;
arthicha 0:a291977ec0b1 298 case GFS_2000DPS:
arthicha 0:a291977ec0b1 299 gRes = 2000.0/32768.0;
arthicha 0:a291977ec0b1 300 break;
arthicha 0:a291977ec0b1 301 }
arthicha 0:a291977ec0b1 302 }
arthicha 0:a291977ec0b1 303
arthicha 0:a291977ec0b1 304
arthicha 0:a291977ec0b1 305 void getAres() {
arthicha 0:a291977ec0b1 306 switch (Ascale)
arthicha 0:a291977ec0b1 307 {
arthicha 0:a291977ec0b1 308 // Possible accelerometer scales (and their register bit settings) are:
arthicha 0:a291977ec0b1 309 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
arthicha 0:a291977ec0b1 310 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
arthicha 0:a291977ec0b1 311 case AFS_2G:
arthicha 0:a291977ec0b1 312 aRes = 2.0/32768.0;
arthicha 0:a291977ec0b1 313 break;
arthicha 0:a291977ec0b1 314 case AFS_4G:
arthicha 0:a291977ec0b1 315 aRes = 4.0/32768.0;
arthicha 0:a291977ec0b1 316 break;
arthicha 0:a291977ec0b1 317 case AFS_8G:
arthicha 0:a291977ec0b1 318 aRes = 8.0/32768.0;
arthicha 0:a291977ec0b1 319 break;
arthicha 0:a291977ec0b1 320 case AFS_16G:
arthicha 0:a291977ec0b1 321 aRes = 16.0/32768.0;
arthicha 0:a291977ec0b1 322 break;
arthicha 0:a291977ec0b1 323 }
arthicha 0:a291977ec0b1 324 }
arthicha 0:a291977ec0b1 325
arthicha 0:a291977ec0b1 326
arthicha 0:a291977ec0b1 327 void readAccelData(int16_t * destination)
arthicha 0:a291977ec0b1 328 {
arthicha 0:a291977ec0b1 329 uint8_t rawData[6]; // x/y/z accel register data stored here
arthicha 0:a291977ec0b1 330 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
arthicha 0:a291977ec0b1 331 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
arthicha 0:a291977ec0b1 332 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
arthicha 0:a291977ec0b1 333 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
arthicha 0:a291977ec0b1 334 }
arthicha 0:a291977ec0b1 335
arthicha 0:a291977ec0b1 336 void readGyroData(int16_t * destination)
arthicha 0:a291977ec0b1 337 {
arthicha 0:a291977ec0b1 338 uint8_t rawData[6]; // x/y/z gyro register data stored here
arthicha 0:a291977ec0b1 339 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
arthicha 0:a291977ec0b1 340 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
arthicha 0:a291977ec0b1 341 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
arthicha 0:a291977ec0b1 342 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
arthicha 0:a291977ec0b1 343 }
arthicha 0:a291977ec0b1 344
arthicha 0:a291977ec0b1 345 void readMagData(int16_t * destination)
arthicha 0:a291977ec0b1 346 {
arthicha 0:a291977ec0b1 347 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
arthicha 0:a291977ec0b1 348 if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set
arthicha 0:a291977ec0b1 349 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
arthicha 0:a291977ec0b1 350 uint8_t c = rawData[6]; // End data read by reading ST2 register
arthicha 0:a291977ec0b1 351 if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data
arthicha 0:a291977ec0b1 352 destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value
arthicha 0:a291977ec0b1 353 destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian
arthicha 0:a291977ec0b1 354 destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ;
arthicha 0:a291977ec0b1 355 }
arthicha 0:a291977ec0b1 356 }
arthicha 0:a291977ec0b1 357 }
arthicha 0:a291977ec0b1 358
arthicha 0:a291977ec0b1 359 int16_t readTempData()
arthicha 0:a291977ec0b1 360 {
arthicha 0:a291977ec0b1 361 uint8_t rawData[2]; // x/y/z gyro register data stored here
arthicha 0:a291977ec0b1 362 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
arthicha 0:a291977ec0b1 363 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
arthicha 0:a291977ec0b1 364 }
arthicha 0:a291977ec0b1 365
arthicha 0:a291977ec0b1 366
arthicha 0:a291977ec0b1 367 void resetMPU9250() {
arthicha 0:a291977ec0b1 368 // reset device
arthicha 0:a291977ec0b1 369 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
arthicha 0:a291977ec0b1 370 wait(0.1);
arthicha 0:a291977ec0b1 371 }
arthicha 0:a291977ec0b1 372
arthicha 0:a291977ec0b1 373 void initAK8963(float * destination)
arthicha 0:a291977ec0b1 374 {
arthicha 0:a291977ec0b1 375 // First extract the factory calibration for each magnetometer axis
arthicha 0:a291977ec0b1 376 uint8_t rawData[3]; // x/y/z gyro calibration data stored here
arthicha 0:a291977ec0b1 377 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
arthicha 0:a291977ec0b1 378 wait(0.01);
arthicha 0:a291977ec0b1 379 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
arthicha 0:a291977ec0b1 380 wait(0.01);
arthicha 0:a291977ec0b1 381 readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
arthicha 0:a291977ec0b1 382 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
arthicha 0:a291977ec0b1 383 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
arthicha 0:a291977ec0b1 384 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
arthicha 0:a291977ec0b1 385 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
arthicha 0:a291977ec0b1 386 wait(0.01);
arthicha 0:a291977ec0b1 387 // Configure the magnetometer for continuous read and highest resolution
arthicha 0:a291977ec0b1 388 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
arthicha 0:a291977ec0b1 389 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
arthicha 0:a291977ec0b1 390 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
arthicha 0:a291977ec0b1 391 wait(0.01);
arthicha 0:a291977ec0b1 392 }
arthicha 0:a291977ec0b1 393
arthicha 0:a291977ec0b1 394
arthicha 0:a291977ec0b1 395 void initMPU9250()
arthicha 0:a291977ec0b1 396 {
arthicha 0:a291977ec0b1 397 // Initialize MPU9250 device
arthicha 0:a291977ec0b1 398 // wake up device
arthicha 0:a291977ec0b1 399 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
arthicha 0:a291977ec0b1 400 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
arthicha 0:a291977ec0b1 401
arthicha 0:a291977ec0b1 402 // get stable time source
arthicha 0:a291977ec0b1 403 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
arthicha 0:a291977ec0b1 404
arthicha 0:a291977ec0b1 405 // Configure Gyro and Accelerometer
arthicha 0:a291977ec0b1 406 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
arthicha 0:a291977ec0b1 407 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
arthicha 0:a291977ec0b1 408 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
arthicha 0:a291977ec0b1 409 writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
arthicha 0:a291977ec0b1 410
arthicha 0:a291977ec0b1 411 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
arthicha 0:a291977ec0b1 412 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
arthicha 0:a291977ec0b1 413
arthicha 0:a291977ec0b1 414 // Set gyroscope full scale range
arthicha 0:a291977ec0b1 415 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
arthicha 0:a291977ec0b1 416 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
arthicha 0:a291977ec0b1 417 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
arthicha 0:a291977ec0b1 418 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
arthicha 0:a291977ec0b1 419 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
arthicha 0:a291977ec0b1 420
arthicha 0:a291977ec0b1 421 // Set accelerometer configuration
arthicha 0:a291977ec0b1 422 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
arthicha 0:a291977ec0b1 423 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
arthicha 0:a291977ec0b1 424 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
arthicha 0:a291977ec0b1 425 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
arthicha 0:a291977ec0b1 426
arthicha 0:a291977ec0b1 427 // Set accelerometer sample rate configuration
arthicha 0:a291977ec0b1 428 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
arthicha 0:a291977ec0b1 429 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
arthicha 0:a291977ec0b1 430 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
arthicha 0:a291977ec0b1 431 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
arthicha 0:a291977ec0b1 432 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
arthicha 0:a291977ec0b1 433
arthicha 0:a291977ec0b1 434 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
arthicha 0:a291977ec0b1 435 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
arthicha 0:a291977ec0b1 436
arthicha 0:a291977ec0b1 437 // Configure Interrupts and Bypass Enable
arthicha 0:a291977ec0b1 438 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
arthicha 0:a291977ec0b1 439 // can join the I2C bus and all can be controlled by the Arduino as master
arthicha 0:a291977ec0b1 440 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
arthicha 0:a291977ec0b1 441 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
arthicha 0:a291977ec0b1 442 }
arthicha 0:a291977ec0b1 443
arthicha 0:a291977ec0b1 444 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
arthicha 0:a291977ec0b1 445 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
arthicha 0:a291977ec0b1 446 void calibrateMPU9250(float * dest1, float * dest2)
arthicha 0:a291977ec0b1 447 {
arthicha 0:a291977ec0b1 448 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
arthicha 0:a291977ec0b1 449 uint16_t ii, packet_count, fifo_count;
arthicha 0:a291977ec0b1 450 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
arthicha 0:a291977ec0b1 451
arthicha 0:a291977ec0b1 452 // reset device, reset all registers, clear gyro and accelerometer bias registers
arthicha 0:a291977ec0b1 453 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
arthicha 0:a291977ec0b1 454 wait(0.1);
arthicha 0:a291977ec0b1 455
arthicha 0:a291977ec0b1 456 // get stable time source
arthicha 0:a291977ec0b1 457 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
arthicha 0:a291977ec0b1 458 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
arthicha 0:a291977ec0b1 459 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
arthicha 0:a291977ec0b1 460 wait(0.2);
arthicha 0:a291977ec0b1 461
arthicha 0:a291977ec0b1 462 // Configure device for bias calculation
arthicha 0:a291977ec0b1 463 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
arthicha 0:a291977ec0b1 464 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
arthicha 0:a291977ec0b1 465 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
arthicha 0:a291977ec0b1 466 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
arthicha 0:a291977ec0b1 467 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
arthicha 0:a291977ec0b1 468 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
arthicha 0:a291977ec0b1 469 wait(0.015);
arthicha 0:a291977ec0b1 470
arthicha 0:a291977ec0b1 471 // Configure MPU9250 gyro and accelerometer for bias calculation
arthicha 0:a291977ec0b1 472 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
arthicha 0:a291977ec0b1 473 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
arthicha 0:a291977ec0b1 474 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
arthicha 0:a291977ec0b1 475 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
arthicha 0:a291977ec0b1 476
arthicha 0:a291977ec0b1 477 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
arthicha 0:a291977ec0b1 478 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
arthicha 0:a291977ec0b1 479
arthicha 0:a291977ec0b1 480 // Configure FIFO to capture accelerometer and gyro data for bias calculation
arthicha 0:a291977ec0b1 481 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
arthicha 0:a291977ec0b1 482 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
arthicha 0:a291977ec0b1 483 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
arthicha 0:a291977ec0b1 484
arthicha 0:a291977ec0b1 485 // At end of sample accumulation, turn off FIFO sensor read
arthicha 0:a291977ec0b1 486 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
arthicha 0:a291977ec0b1 487 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
arthicha 0:a291977ec0b1 488 fifo_count = ((uint16_t)data[0] << 8) | data[1];
arthicha 0:a291977ec0b1 489 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
arthicha 0:a291977ec0b1 490
arthicha 0:a291977ec0b1 491 for (ii = 0; ii < packet_count; ii++) {
arthicha 0:a291977ec0b1 492 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
arthicha 0:a291977ec0b1 493 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
arthicha 0:a291977ec0b1 494 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
arthicha 0:a291977ec0b1 495 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
arthicha 0:a291977ec0b1 496 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
arthicha 0:a291977ec0b1 497 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
arthicha 0:a291977ec0b1 498 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
arthicha 0:a291977ec0b1 499 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
arthicha 0:a291977ec0b1 500
arthicha 0:a291977ec0b1 501 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
arthicha 0:a291977ec0b1 502 accel_bias[1] += (int32_t) accel_temp[1];
arthicha 0:a291977ec0b1 503 accel_bias[2] += (int32_t) accel_temp[2];
arthicha 0:a291977ec0b1 504 gyro_bias[0] += (int32_t) gyro_temp[0];
arthicha 0:a291977ec0b1 505 gyro_bias[1] += (int32_t) gyro_temp[1];
arthicha 0:a291977ec0b1 506 gyro_bias[2] += (int32_t) gyro_temp[2];
arthicha 0:a291977ec0b1 507
arthicha 0:a291977ec0b1 508 }
arthicha 0:a291977ec0b1 509 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
arthicha 0:a291977ec0b1 510 accel_bias[1] /= (int32_t) packet_count;
arthicha 0:a291977ec0b1 511 accel_bias[2] /= (int32_t) packet_count;
arthicha 0:a291977ec0b1 512 gyro_bias[0] /= (int32_t) packet_count;
arthicha 0:a291977ec0b1 513 gyro_bias[1] /= (int32_t) packet_count;
arthicha 0:a291977ec0b1 514 gyro_bias[2] /= (int32_t) packet_count;
arthicha 0:a291977ec0b1 515
arthicha 0:a291977ec0b1 516 if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation
arthicha 0:a291977ec0b1 517 else {accel_bias[2] += (int32_t) accelsensitivity;}
arthicha 0:a291977ec0b1 518
arthicha 0:a291977ec0b1 519 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
arthicha 0:a291977ec0b1 520 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
arthicha 0:a291977ec0b1 521 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
arthicha 0:a291977ec0b1 522 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
arthicha 0:a291977ec0b1 523 data[3] = (-gyro_bias[1]/4) & 0xFF;
arthicha 0:a291977ec0b1 524 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
arthicha 0:a291977ec0b1 525 data[5] = (-gyro_bias[2]/4) & 0xFF;
arthicha 0:a291977ec0b1 526
arthicha 0:a291977ec0b1 527 /// Push gyro biases to hardware registers
arthicha 0:a291977ec0b1 528 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
arthicha 0:a291977ec0b1 529 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
arthicha 0:a291977ec0b1 530 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
arthicha 0:a291977ec0b1 531 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
arthicha 0:a291977ec0b1 532 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
arthicha 0:a291977ec0b1 533 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);
arthicha 0:a291977ec0b1 534 */
arthicha 0:a291977ec0b1 535 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
arthicha 0:a291977ec0b1 536 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
arthicha 0:a291977ec0b1 537 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
arthicha 0:a291977ec0b1 538
arthicha 0:a291977ec0b1 539 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
arthicha 0:a291977ec0b1 540 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
arthicha 0:a291977ec0b1 541 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
arthicha 0:a291977ec0b1 542 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
arthicha 0:a291977ec0b1 543 // the accelerometer biases calculated above must be divided by 8.
arthicha 0:a291977ec0b1 544
arthicha 0:a291977ec0b1 545 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
arthicha 0:a291977ec0b1 546 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
arthicha 0:a291977ec0b1 547 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
arthicha 0:a291977ec0b1 548 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
arthicha 0:a291977ec0b1 549 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
arthicha 0:a291977ec0b1 550 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
arthicha 0:a291977ec0b1 551 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
arthicha 0:a291977ec0b1 552
arthicha 0:a291977ec0b1 553 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
arthicha 0:a291977ec0b1 554 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
arthicha 0:a291977ec0b1 555
arthicha 0:a291977ec0b1 556 for(ii = 0; ii < 3; ii++) {
arthicha 0:a291977ec0b1 557 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
arthicha 0:a291977ec0b1 558 }
arthicha 0:a291977ec0b1 559
arthicha 0:a291977ec0b1 560 // Construct total accelerometer bias, including calculated average accelerometer bias from above
arthicha 0:a291977ec0b1 561 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
arthicha 0:a291977ec0b1 562 accel_bias_reg[1] -= (accel_bias[1]/8);
arthicha 0:a291977ec0b1 563 accel_bias_reg[2] -= (accel_bias[2]/8);
arthicha 0:a291977ec0b1 564
arthicha 0:a291977ec0b1 565 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
arthicha 0:a291977ec0b1 566 data[1] = (accel_bias_reg[0]) & 0xFF;
arthicha 0:a291977ec0b1 567 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
arthicha 0:a291977ec0b1 568 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
arthicha 0:a291977ec0b1 569 data[3] = (accel_bias_reg[1]) & 0xFF;
arthicha 0:a291977ec0b1 570 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
arthicha 0:a291977ec0b1 571 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
arthicha 0:a291977ec0b1 572 data[5] = (accel_bias_reg[2]) & 0xFF;
arthicha 0:a291977ec0b1 573 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
arthicha 0:a291977ec0b1 574
arthicha 0:a291977ec0b1 575 // Apparently this is not working for the acceleration biases in the MPU-9250
arthicha 0:a291977ec0b1 576 // Are we handling the temperature correction bit properly?
arthicha 0:a291977ec0b1 577 // Push accelerometer biases to hardware registers
arthicha 0:a291977ec0b1 578 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
arthicha 0:a291977ec0b1 579 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
arthicha 0:a291977ec0b1 580 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
arthicha 0:a291977ec0b1 581 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
arthicha 0:a291977ec0b1 582 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
arthicha 0:a291977ec0b1 583 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);
arthicha 0:a291977ec0b1 584 */
arthicha 0:a291977ec0b1 585 // Output scaled accelerometer biases for manual subtraction in the main program
arthicha 0:a291977ec0b1 586 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity;
arthicha 0:a291977ec0b1 587 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity;
arthicha 0:a291977ec0b1 588 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
arthicha 0:a291977ec0b1 589 }
arthicha 0:a291977ec0b1 590
arthicha 0:a291977ec0b1 591
arthicha 0:a291977ec0b1 592 // Accelerometer and gyroscope self test; check calibration wrt factory settings
arthicha 0:a291977ec0b1 593 void MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
arthicha 0:a291977ec0b1 594 {
arthicha 0:a291977ec0b1 595 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
arthicha 0:a291977ec0b1 596 uint8_t selfTest[6];
arthicha 0:a291977ec0b1 597 int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3];
arthicha 0:a291977ec0b1 598 float factoryTrim[6];
arthicha 0:a291977ec0b1 599 uint8_t FS = 0;
arthicha 0:a291977ec0b1 600
arthicha 0:a291977ec0b1 601 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
arthicha 0:a291977ec0b1 602 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
arthicha 0:a291977ec0b1 603 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
arthicha 0:a291977ec0b1 604 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
arthicha 0:a291977ec0b1 605 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
arthicha 0:a291977ec0b1 606
arthicha 0:a291977ec0b1 607 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
arthicha 0:a291977ec0b1 608
arthicha 0:a291977ec0b1 609 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
arthicha 0:a291977ec0b1 610 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
arthicha 0:a291977ec0b1 611 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
arthicha 0:a291977ec0b1 612 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
arthicha 0:a291977ec0b1 613
arthicha 0:a291977ec0b1 614 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
arthicha 0:a291977ec0b1 615 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
arthicha 0:a291977ec0b1 616 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
arthicha 0:a291977ec0b1 617 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
arthicha 0:a291977ec0b1 618 }
arthicha 0:a291977ec0b1 619
arthicha 0:a291977ec0b1 620 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
arthicha 0:a291977ec0b1 621 aAvg[ii] /= 200;
arthicha 0:a291977ec0b1 622 gAvg[ii] /= 200;
arthicha 0:a291977ec0b1 623 }
arthicha 0:a291977ec0b1 624
arthicha 0:a291977ec0b1 625 // Configure the accelerometer for self-test
arthicha 0:a291977ec0b1 626 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
arthicha 0:a291977ec0b1 627 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
arthicha 0:a291977ec0b1 628 wait_ms(25); // Delay a while to let the device stabilize
arthicha 0:a291977ec0b1 629
arthicha 0:a291977ec0b1 630 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
arthicha 0:a291977ec0b1 631
arthicha 0:a291977ec0b1 632 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
arthicha 0:a291977ec0b1 633 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
arthicha 0:a291977ec0b1 634 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
arthicha 0:a291977ec0b1 635 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
arthicha 0:a291977ec0b1 636
arthicha 0:a291977ec0b1 637 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
arthicha 0:a291977ec0b1 638 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
arthicha 0:a291977ec0b1 639 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
arthicha 0:a291977ec0b1 640 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
arthicha 0:a291977ec0b1 641 }
arthicha 0:a291977ec0b1 642
arthicha 0:a291977ec0b1 643 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
arthicha 0:a291977ec0b1 644 aSTAvg[ii] /= 200;
arthicha 0:a291977ec0b1 645 gSTAvg[ii] /= 200;
arthicha 0:a291977ec0b1 646 }
arthicha 0:a291977ec0b1 647
arthicha 0:a291977ec0b1 648 // Configure the gyro and accelerometer for normal operation
arthicha 0:a291977ec0b1 649 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
arthicha 0:a291977ec0b1 650 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
arthicha 0:a291977ec0b1 651 wait_ms(25); // Delay a while to let the device stabilize
arthicha 0:a291977ec0b1 652
arthicha 0:a291977ec0b1 653 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
arthicha 0:a291977ec0b1 654 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
arthicha 0:a291977ec0b1 655 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
arthicha 0:a291977ec0b1 656 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
arthicha 0:a291977ec0b1 657 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
arthicha 0:a291977ec0b1 658 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
arthicha 0:a291977ec0b1 659 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
arthicha 0:a291977ec0b1 660
arthicha 0:a291977ec0b1 661 // Retrieve factory self-test value from self-test code reads
arthicha 0:a291977ec0b1 662 factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation
arthicha 0:a291977ec0b1 663 factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation
arthicha 0:a291977ec0b1 664 factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation
arthicha 0:a291977ec0b1 665 factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation
arthicha 0:a291977ec0b1 666 factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation
arthicha 0:a291977ec0b1 667 factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation
arthicha 0:a291977ec0b1 668
arthicha 0:a291977ec0b1 669 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
arthicha 0:a291977ec0b1 670 // To get percent, must multiply by 100
arthicha 0:a291977ec0b1 671 for (int i = 0; i < 3; i++) {
arthicha 0:a291977ec0b1 672 destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences
arthicha 0:a291977ec0b1 673 destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences
arthicha 0:a291977ec0b1 674 }
arthicha 0:a291977ec0b1 675
arthicha 0:a291977ec0b1 676 }
arthicha 0:a291977ec0b1 677
arthicha 0:a291977ec0b1 678
arthicha 0:a291977ec0b1 679
arthicha 0:a291977ec0b1 680 // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
arthicha 0:a291977ec0b1 681 // (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
arthicha 0:a291977ec0b1 682 // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute
arthicha 0:a291977ec0b1 683 // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
arthicha 0:a291977ec0b1 684 // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
arthicha 0:a291977ec0b1 685 // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
arthicha 0:a291977ec0b1 686 void Mad_Update(float ax, float ay, float az, float gx, float gy, float gz)
arthicha 0:a291977ec0b1 687 {
arthicha 0:a291977ec0b1 688 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
arthicha 0:a291977ec0b1 689 float norm; // vector norm
arthicha 0:a291977ec0b1 690 float f1, f2, f3; // objective funcyion elements
arthicha 0:a291977ec0b1 691 float J_11or24, J_12or23, J_13or22, J_14or21, J_32, J_33; // objective function Jacobian elements
arthicha 0:a291977ec0b1 692 float qDot1, qDot2, qDot3, qDot4;
arthicha 0:a291977ec0b1 693 float hatDot1, hatDot2, hatDot3, hatDot4;
arthicha 0:a291977ec0b1 694 float gerrx, gerry, gerrz, gbiasx, gbiasy, gbiasz; // gyro bias error
arthicha 0:a291977ec0b1 695
arthicha 0:a291977ec0b1 696 // Auxiliary variables to avoid repeated arithmetic
arthicha 0:a291977ec0b1 697 float _halfq1 = 0.5f * q1;
arthicha 0:a291977ec0b1 698 float _halfq2 = 0.5f * q2;
arthicha 0:a291977ec0b1 699 float _halfq3 = 0.5f * q3;
arthicha 0:a291977ec0b1 700 float _halfq4 = 0.5f * q4;
arthicha 0:a291977ec0b1 701 float _2q1 = 2.0f * q1;
arthicha 0:a291977ec0b1 702 float _2q2 = 2.0f * q2;
arthicha 0:a291977ec0b1 703 float _2q3 = 2.0f * q3;
arthicha 0:a291977ec0b1 704 float _2q4 = 2.0f * q4;
arthicha 0:a291977ec0b1 705 // float _2q1q3 = 2.0f * q1 * q3;
arthicha 0:a291977ec0b1 706 // float _2q3q4 = 2.0f * q3 * q4;
arthicha 0:a291977ec0b1 707
arthicha 0:a291977ec0b1 708 // Normalise accelerometer measurement
arthicha 0:a291977ec0b1 709 norm = sqrt(ax * ax + ay * ay + az * az);
arthicha 0:a291977ec0b1 710 if (norm == 0.0f) return; // handle NaN
arthicha 0:a291977ec0b1 711 norm = 1.0f/norm;
arthicha 0:a291977ec0b1 712 ax *= norm;
arthicha 0:a291977ec0b1 713 ay *= norm;
arthicha 0:a291977ec0b1 714 az *= norm;
arthicha 0:a291977ec0b1 715
arthicha 0:a291977ec0b1 716 // Compute the objective function and Jacobian
arthicha 0:a291977ec0b1 717 f1 = _2q2 * q4 - _2q1 * q3 - ax;
arthicha 0:a291977ec0b1 718 f2 = _2q1 * q2 + _2q3 * q4 - ay;
arthicha 0:a291977ec0b1 719 f3 = 1.0f - _2q2 * q2 - _2q3 * q3 - az;
arthicha 0:a291977ec0b1 720 J_11or24 = _2q3;
arthicha 0:a291977ec0b1 721 J_12or23 = _2q4;
arthicha 0:a291977ec0b1 722 J_13or22 = _2q1;
arthicha 0:a291977ec0b1 723 J_14or21 = _2q2;
arthicha 0:a291977ec0b1 724 J_32 = 2.0f * J_14or21;
arthicha 0:a291977ec0b1 725 J_33 = 2.0f * J_11or24;
arthicha 0:a291977ec0b1 726
arthicha 0:a291977ec0b1 727 // Compute the gradient (matrix multiplication)
arthicha 0:a291977ec0b1 728 hatDot1 = J_14or21 * f2 - J_11or24 * f1;
arthicha 0:a291977ec0b1 729 hatDot2 = J_12or23 * f1 + J_13or22 * f2 - J_32 * f3;
arthicha 0:a291977ec0b1 730 hatDot3 = J_12or23 * f2 - J_33 *f3 - J_13or22 * f1;
arthicha 0:a291977ec0b1 731 hatDot4 = J_14or21 * f1 + J_11or24 * f2;
arthicha 0:a291977ec0b1 732
arthicha 0:a291977ec0b1 733 // Normalize the gradient
arthicha 0:a291977ec0b1 734 norm = sqrt(hatDot1 * hatDot1 + hatDot2 * hatDot2 + hatDot3 * hatDot3 + hatDot4 * hatDot4);
arthicha 0:a291977ec0b1 735 hatDot1 /= norm;
arthicha 0:a291977ec0b1 736 hatDot2 /= norm;
arthicha 0:a291977ec0b1 737 hatDot3 /= norm;
arthicha 0:a291977ec0b1 738 hatDot4 /= norm;
arthicha 0:a291977ec0b1 739
arthicha 0:a291977ec0b1 740 // Compute estimated gyroscope biases
arthicha 0:a291977ec0b1 741 gerrx = _2q1 * hatDot2 - _2q2 * hatDot1 - _2q3 * hatDot4 + _2q4 * hatDot3;
arthicha 0:a291977ec0b1 742 gerry = _2q1 * hatDot3 + _2q2 * hatDot4 - _2q3 * hatDot1 - _2q4 * hatDot2;
arthicha 0:a291977ec0b1 743 gerrz = _2q1 * hatDot4 - _2q2 * hatDot3 + _2q3 * hatDot2 - _2q4 * hatDot1;
arthicha 0:a291977ec0b1 744
arthicha 0:a291977ec0b1 745 // Compute and remove gyroscope biases
arthicha 0:a291977ec0b1 746 gbiasx += gerrx * deltat * zeta;
arthicha 0:a291977ec0b1 747 gbiasy += gerry * deltat * zeta;
arthicha 0:a291977ec0b1 748 gbiasz += gerrz * deltat * zeta;
arthicha 0:a291977ec0b1 749 // gx -= gbiasx;
arthicha 0:a291977ec0b1 750 // gy -= gbiasy;
arthicha 0:a291977ec0b1 751 // gz -= gbiasz;
arthicha 0:a291977ec0b1 752
arthicha 0:a291977ec0b1 753 // Compute the quaternion derivative
arthicha 0:a291977ec0b1 754 qDot1 = -_halfq2 * gx - _halfq3 * gy - _halfq4 * gz;
arthicha 0:a291977ec0b1 755 qDot2 = _halfq1 * gx + _halfq3 * gz - _halfq4 * gy;
arthicha 0:a291977ec0b1 756 qDot3 = _halfq1 * gy - _halfq2 * gz + _halfq4 * gx;
arthicha 0:a291977ec0b1 757 qDot4 = _halfq1 * gz + _halfq2 * gy - _halfq3 * gx;
arthicha 0:a291977ec0b1 758
arthicha 0:a291977ec0b1 759 // Compute then integrate estimated quaternion derivative
arthicha 0:a291977ec0b1 760 q1 += (qDot1 -(beta * hatDot1)) * deltat;
arthicha 0:a291977ec0b1 761 q2 += (qDot2 -(beta * hatDot2)) * deltat;
arthicha 0:a291977ec0b1 762 q3 += (qDot3 -(beta * hatDot3)) * deltat;
arthicha 0:a291977ec0b1 763 q4 += (qDot4 -(beta * hatDot4)) * deltat;
arthicha 0:a291977ec0b1 764
arthicha 0:a291977ec0b1 765 // Normalize the quaternion
arthicha 0:a291977ec0b1 766 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
arthicha 0:a291977ec0b1 767 norm = 1.0f/norm;
arthicha 0:a291977ec0b1 768 q[0] = q1 * norm;
arthicha 0:a291977ec0b1 769 q[1] = q2 * norm;
arthicha 0:a291977ec0b1 770 q[2] = q3 * norm;
arthicha 0:a291977ec0b1 771 q[3] = q4 * norm;
arthicha 0:a291977ec0b1 772
arthicha 0:a291977ec0b1 773 }
arthicha 0:a291977ec0b1 774
arthicha 0:a291977ec0b1 775 void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
arthicha 0:a291977ec0b1 776 {
arthicha 0:a291977ec0b1 777 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
arthicha 0:a291977ec0b1 778 float norm;
arthicha 0:a291977ec0b1 779 float hx, hy, _2bx, _2bz;
arthicha 0:a291977ec0b1 780 float s1, s2, s3, s4;
arthicha 0:a291977ec0b1 781 float qDot1, qDot2, qDot3, qDot4;
arthicha 0:a291977ec0b1 782
arthicha 0:a291977ec0b1 783 // Auxiliary variables to avoid repeated arithmetic
arthicha 0:a291977ec0b1 784 float _2q1mx;
arthicha 0:a291977ec0b1 785 float _2q1my;
arthicha 0:a291977ec0b1 786 float _2q1mz;
arthicha 0:a291977ec0b1 787 float _2q2mx;
arthicha 0:a291977ec0b1 788 float _4bx;
arthicha 0:a291977ec0b1 789 float _4bz;
arthicha 0:a291977ec0b1 790 float _2q1 = 2.0f * q1;
arthicha 0:a291977ec0b1 791 float _2q2 = 2.0f * q2;
arthicha 0:a291977ec0b1 792 float _2q3 = 2.0f * q3;
arthicha 0:a291977ec0b1 793 float _2q4 = 2.0f * q4;
arthicha 0:a291977ec0b1 794 float _2q1q3 = 2.0f * q1 * q3;
arthicha 0:a291977ec0b1 795 float _2q3q4 = 2.0f * q3 * q4;
arthicha 0:a291977ec0b1 796 float q1q1 = q1 * q1;
arthicha 0:a291977ec0b1 797 float q1q2 = q1 * q2;
arthicha 0:a291977ec0b1 798 float q1q3 = q1 * q3;
arthicha 0:a291977ec0b1 799 float q1q4 = q1 * q4;
arthicha 0:a291977ec0b1 800 float q2q2 = q2 * q2;
arthicha 0:a291977ec0b1 801 float q2q3 = q2 * q3;
arthicha 0:a291977ec0b1 802 float q2q4 = q2 * q4;
arthicha 0:a291977ec0b1 803 float q3q3 = q3 * q3;
arthicha 0:a291977ec0b1 804 float q3q4 = q3 * q4;
arthicha 0:a291977ec0b1 805 float q4q4 = q4 * q4;
arthicha 0:a291977ec0b1 806
arthicha 0:a291977ec0b1 807 // Normalise accelerometer measurement
arthicha 0:a291977ec0b1 808 norm = sqrt(ax * ax + ay * ay + az * az);
arthicha 0:a291977ec0b1 809 if (norm == 0.0f) return; // handle NaN
arthicha 0:a291977ec0b1 810 norm = 1.0f/norm;
arthicha 0:a291977ec0b1 811 ax *= norm;
arthicha 0:a291977ec0b1 812 ay *= norm;
arthicha 0:a291977ec0b1 813 az *= norm;
arthicha 0:a291977ec0b1 814
arthicha 0:a291977ec0b1 815 // Normalise magnetometer measurement
arthicha 0:a291977ec0b1 816 norm = sqrt(mx * mx + my * my + mz * mz);
arthicha 0:a291977ec0b1 817 if (norm == 0.0f) return; // handle NaN
arthicha 0:a291977ec0b1 818 norm = 1.0f/norm;
arthicha 0:a291977ec0b1 819 mx *= norm;
arthicha 0:a291977ec0b1 820 my *= norm;
arthicha 0:a291977ec0b1 821 mz *= norm;
arthicha 0:a291977ec0b1 822
arthicha 0:a291977ec0b1 823 // Reference direction of Earth's magnetic field
arthicha 0:a291977ec0b1 824 _2q1mx = 2.0f * q1 * mx;
arthicha 0:a291977ec0b1 825 _2q1my = 2.0f * q1 * my;
arthicha 0:a291977ec0b1 826 _2q1mz = 2.0f * q1 * mz;
arthicha 0:a291977ec0b1 827 _2q2mx = 2.0f * q2 * mx;
arthicha 0:a291977ec0b1 828 hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4;
arthicha 0:a291977ec0b1 829 hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4;
arthicha 0:a291977ec0b1 830 _2bx = sqrt(hx * hx + hy * hy);
arthicha 0:a291977ec0b1 831 _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4;
arthicha 0:a291977ec0b1 832 _4bx = 2.0f * _2bx;
arthicha 0:a291977ec0b1 833 _4bz = 2.0f * _2bz;
arthicha 0:a291977ec0b1 834
arthicha 0:a291977ec0b1 835 // Gradient decent algorithm corrective step
arthicha 0:a291977ec0b1 836 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);
arthicha 0:a291977ec0b1 837 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);
arthicha 0:a291977ec0b1 838 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);
arthicha 0:a291977ec0b1 839 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);
arthicha 0:a291977ec0b1 840 norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude
arthicha 0:a291977ec0b1 841 norm = 1.0f/norm;
arthicha 0:a291977ec0b1 842 s1 *= norm;
arthicha 0:a291977ec0b1 843 s2 *= norm;
arthicha 0:a291977ec0b1 844 s3 *= norm;
arthicha 0:a291977ec0b1 845 s4 *= norm;
arthicha 0:a291977ec0b1 846
arthicha 0:a291977ec0b1 847 // Compute rate of change of quaternion
arthicha 0:a291977ec0b1 848 qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1;
arthicha 0:a291977ec0b1 849 qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2;
arthicha 0:a291977ec0b1 850 qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3;
arthicha 0:a291977ec0b1 851 qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4;
arthicha 0:a291977ec0b1 852
arthicha 0:a291977ec0b1 853 // Integrate to yield quaternion
arthicha 0:a291977ec0b1 854 q1 += qDot1 * deltat;
arthicha 0:a291977ec0b1 855 q2 += qDot2 * deltat;
arthicha 0:a291977ec0b1 856 q3 += qDot3 * deltat;
arthicha 0:a291977ec0b1 857 q4 += qDot4 * deltat;
arthicha 0:a291977ec0b1 858 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
arthicha 0:a291977ec0b1 859 norm = 1.0f/norm;
arthicha 0:a291977ec0b1 860 q[0] = q1 * norm;
arthicha 0:a291977ec0b1 861 q[1] = q2 * norm;
arthicha 0:a291977ec0b1 862 q[2] = q3 * norm;
arthicha 0:a291977ec0b1 863 q[3] = q4 * norm;
arthicha 0:a291977ec0b1 864
arthicha 0:a291977ec0b1 865 }
arthicha 0:a291977ec0b1 866
arthicha 0:a291977ec0b1 867
arthicha 0:a291977ec0b1 868
arthicha 0:a291977ec0b1 869 // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and
arthicha 0:a291977ec0b1 870 // measured ones.
arthicha 0:a291977ec0b1 871 void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
arthicha 0:a291977ec0b1 872 {
arthicha 0:a291977ec0b1 873 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
arthicha 0:a291977ec0b1 874 float norm;
arthicha 0:a291977ec0b1 875 float hx, hy, bx, bz;
arthicha 0:a291977ec0b1 876 float vx, vy, vz, wx, wy, wz;
arthicha 0:a291977ec0b1 877 float ex, ey, ez;
arthicha 0:a291977ec0b1 878 float pa, pb, pc;
arthicha 0:a291977ec0b1 879
arthicha 0:a291977ec0b1 880 // Auxiliary variables to avoid repeated arithmetic
arthicha 0:a291977ec0b1 881 float q1q1 = q1 * q1;
arthicha 0:a291977ec0b1 882 float q1q2 = q1 * q2;
arthicha 0:a291977ec0b1 883 float q1q3 = q1 * q3;
arthicha 0:a291977ec0b1 884 float q1q4 = q1 * q4;
arthicha 0:a291977ec0b1 885 float q2q2 = q2 * q2;
arthicha 0:a291977ec0b1 886 float q2q3 = q2 * q3;
arthicha 0:a291977ec0b1 887 float q2q4 = q2 * q4;
arthicha 0:a291977ec0b1 888 float q3q3 = q3 * q3;
arthicha 0:a291977ec0b1 889 float q3q4 = q3 * q4;
arthicha 0:a291977ec0b1 890 float q4q4 = q4 * q4;
arthicha 0:a291977ec0b1 891
arthicha 0:a291977ec0b1 892 // Normalise accelerometer measurement
arthicha 0:a291977ec0b1 893 norm = sqrt(ax * ax + ay * ay + az * az);
arthicha 0:a291977ec0b1 894 if (norm == 0.0f) return; // handle NaN
arthicha 0:a291977ec0b1 895 norm = 1.0f / norm; // use reciprocal for division
arthicha 0:a291977ec0b1 896 ax *= norm;
arthicha 0:a291977ec0b1 897 ay *= norm;
arthicha 0:a291977ec0b1 898 az *= norm;
arthicha 0:a291977ec0b1 899
arthicha 0:a291977ec0b1 900 // Normalise magnetometer measurement
arthicha 0:a291977ec0b1 901 norm = sqrt(mx * mx + my * my + mz * mz);
arthicha 0:a291977ec0b1 902 if (norm == 0.0f) return; // handle NaN
arthicha 0:a291977ec0b1 903 norm = 1.0f / norm; // use reciprocal for division
arthicha 0:a291977ec0b1 904 mx *= norm;
arthicha 0:a291977ec0b1 905 my *= norm;
arthicha 0:a291977ec0b1 906 mz *= norm;
arthicha 0:a291977ec0b1 907
arthicha 0:a291977ec0b1 908 // Reference direction of Earth's magnetic field
arthicha 0:a291977ec0b1 909 hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3);
arthicha 0:a291977ec0b1 910 hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2);
arthicha 0:a291977ec0b1 911 bx = sqrt((hx * hx) + (hy * hy));
arthicha 0:a291977ec0b1 912 bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3);
arthicha 0:a291977ec0b1 913
arthicha 0:a291977ec0b1 914 // Estimated direction of gravity and magnetic field
arthicha 0:a291977ec0b1 915 vx = 2.0f * (q2q4 - q1q3);
arthicha 0:a291977ec0b1 916 vy = 2.0f * (q1q2 + q3q4);
arthicha 0:a291977ec0b1 917 vz = q1q1 - q2q2 - q3q3 + q4q4;
arthicha 0:a291977ec0b1 918 wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3);
arthicha 0:a291977ec0b1 919 wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4);
arthicha 0:a291977ec0b1 920 wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3);
arthicha 0:a291977ec0b1 921
arthicha 0:a291977ec0b1 922 // Error is cross product between estimated direction and measured direction of gravity
arthicha 0:a291977ec0b1 923 ex = (ay * vz - az * vy) + (my * wz - mz * wy);
arthicha 0:a291977ec0b1 924 ey = (az * vx - ax * vz) + (mz * wx - mx * wz);
arthicha 0:a291977ec0b1 925 ez = (ax * vy - ay * vx) + (mx * wy - my * wx);
arthicha 0:a291977ec0b1 926 if (Ki > 0.0f)
arthicha 0:a291977ec0b1 927 {
arthicha 0:a291977ec0b1 928 eInt[0] += ex; // accumulate integral error
arthicha 0:a291977ec0b1 929 eInt[1] += ey;
arthicha 0:a291977ec0b1 930 eInt[2] += ez;
arthicha 0:a291977ec0b1 931 }
arthicha 0:a291977ec0b1 932 else
arthicha 0:a291977ec0b1 933 {
arthicha 0:a291977ec0b1 934 eInt[0] = 0.0f; // prevent integral wind up
arthicha 0:a291977ec0b1 935 eInt[1] = 0.0f;
arthicha 0:a291977ec0b1 936 eInt[2] = 0.0f;
arthicha 0:a291977ec0b1 937 }
arthicha 0:a291977ec0b1 938
arthicha 0:a291977ec0b1 939 // Apply feedback terms
arthicha 0:a291977ec0b1 940 gx = gx + Kp * ex + Ki * eInt[0];
arthicha 0:a291977ec0b1 941 gy = gy + Kp * ey + Ki * eInt[1];
arthicha 0:a291977ec0b1 942 gz = gz + Kp * ez + Ki * eInt[2];
arthicha 0:a291977ec0b1 943
arthicha 0:a291977ec0b1 944 // Integrate rate of change of quaternion
arthicha 0:a291977ec0b1 945 pa = q2;
arthicha 0:a291977ec0b1 946 pb = q3;
arthicha 0:a291977ec0b1 947 pc = q4;
arthicha 0:a291977ec0b1 948 q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat);
arthicha 0:a291977ec0b1 949 q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat);
arthicha 0:a291977ec0b1 950 q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat);
arthicha 0:a291977ec0b1 951 q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat);
arthicha 0:a291977ec0b1 952
arthicha 0:a291977ec0b1 953 // Normalise quaternion
arthicha 0:a291977ec0b1 954 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);
arthicha 0:a291977ec0b1 955 norm = 1.0f / norm;
arthicha 0:a291977ec0b1 956 q[0] = q1 * norm;
arthicha 0:a291977ec0b1 957 q[1] = q2 * norm;
arthicha 0:a291977ec0b1 958 q[2] = q3 * norm;
arthicha 0:a291977ec0b1 959 q[3] = q4 * norm;
arthicha 0:a291977ec0b1 960
arthicha 0:a291977ec0b1 961 }
arthicha 0:a291977ec0b1 962 };
arthicha 0:a291977ec0b1 963 #endif