Nilli Martínez / Mbed 2 deprecated F-CubeSatKit4

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Dependencies:   BMP180 INA219 JPEGCamera SDFileSystem ST7735_TFT Si7021 TSL2561 mbed

MPU9250.h@0:7fa3463671dd, 2017-03-25 (annotated)

Committer:
NilliM
Date:
Sat Mar 25 01:45:20 2017 +0000
Revision:
0:7fa3463671dd
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Who changed what in which revision?

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NilliM 0:7fa3463671dd 1 #ifndef MPU9250_H
NilliM 0:7fa3463671dd 2 #define MPU9250_H
NilliM 0:7fa3463671dd 3
NilliM 0:7fa3463671dd 4 #include "mbed.h"
NilliM 0:7fa3463671dd 5 #include "math.h"
NilliM 0:7fa3463671dd 6
NilliM 0:7fa3463671dd 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
NilliM 0:7fa3463671dd 8 // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map
NilliM 0:7fa3463671dd 9 //
NilliM 0:7fa3463671dd 10 //Magnetometer Registers
NilliM 0:7fa3463671dd 11 #define AK8963_ADDRESS 0x0C<<1
NilliM 0:7fa3463671dd 12 #define WHO_AM_I_AK8963 0x00 // should return 0x48
NilliM 0:7fa3463671dd 13 #define INFO 0x01
NilliM 0:7fa3463671dd 14 #define AK8963_ST1 0x02 // data ready status bit 0
NilliM 0:7fa3463671dd 15 #define AK8963_XOUT_L 0x03 // data
NilliM 0:7fa3463671dd 16 #define AK8963_XOUT_H 0x04
NilliM 0:7fa3463671dd 17 #define AK8963_YOUT_L 0x05
NilliM 0:7fa3463671dd 18 #define AK8963_YOUT_H 0x06
NilliM 0:7fa3463671dd 19 #define AK8963_ZOUT_L 0x07
NilliM 0:7fa3463671dd 20 #define AK8963_ZOUT_H 0x08
NilliM 0:7fa3463671dd 21 #define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status bit 2
NilliM 0:7fa3463671dd 22 #define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001), self-test (1000) and Fuse ROM (1111) modes on bits 3:0
NilliM 0:7fa3463671dd 23 #define AK8963_ASTC 0x0C // Self test control
NilliM 0:7fa3463671dd 24 #define AK8963_I2CDIS 0x0F // I2C disable
NilliM 0:7fa3463671dd 25 #define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value
NilliM 0:7fa3463671dd 26 #define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value
NilliM 0:7fa3463671dd 27 #define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value
NilliM 0:7fa3463671dd 28
NilliM 0:7fa3463671dd 29 #define SELF_TEST_X_GYRO 0x00
NilliM 0:7fa3463671dd 30 #define SELF_TEST_Y_GYRO 0x01
NilliM 0:7fa3463671dd 31 #define SELF_TEST_Z_GYRO 0x02
NilliM 0:7fa3463671dd 32
NilliM 0:7fa3463671dd 33 /*#define X_FINE_GAIN 0x03 // [7:0] fine gain
NilliM 0:7fa3463671dd 34 #define Y_FINE_GAIN 0x04
NilliM 0:7fa3463671dd 35 #define Z_FINE_GAIN 0x05
NilliM 0:7fa3463671dd 36 #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer
NilliM 0:7fa3463671dd 37 #define XA_OFFSET_L_TC 0x07
NilliM 0:7fa3463671dd 38 #define YA_OFFSET_H 0x08
NilliM 0:7fa3463671dd 39 #define YA_OFFSET_L_TC 0x09
NilliM 0:7fa3463671dd 40 #define ZA_OFFSET_H 0x0A
NilliM 0:7fa3463671dd 41 #define ZA_OFFSET_L_TC 0x0B */
NilliM 0:7fa3463671dd 42
NilliM 0:7fa3463671dd 43 #define SELF_TEST_X_ACCEL 0x0D
NilliM 0:7fa3463671dd 44 #define SELF_TEST_Y_ACCEL 0x0E
NilliM 0:7fa3463671dd 45 #define SELF_TEST_Z_ACCEL 0x0F
NilliM 0:7fa3463671dd 46
NilliM 0:7fa3463671dd 47 #define SELF_TEST_A 0x10
NilliM 0:7fa3463671dd 48
NilliM 0:7fa3463671dd 49 #define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope
NilliM 0:7fa3463671dd 50 #define XG_OFFSET_L 0x14
NilliM 0:7fa3463671dd 51 #define YG_OFFSET_H 0x15
NilliM 0:7fa3463671dd 52 #define YG_OFFSET_L 0x16
NilliM 0:7fa3463671dd 53 #define ZG_OFFSET_H 0x17
NilliM 0:7fa3463671dd 54 #define ZG_OFFSET_L 0x18
NilliM 0:7fa3463671dd 55 #define SMPLRT_DIV 0x19
NilliM 0:7fa3463671dd 56 #define CONFIG 0x1A
NilliM 0:7fa3463671dd 57 #define GYRO_CONFIG 0x1B
NilliM 0:7fa3463671dd 58 #define ACCEL_CONFIG 0x1C
NilliM 0:7fa3463671dd 59 #define ACCEL_CONFIG2 0x1D
NilliM 0:7fa3463671dd 60 #define LP_ACCEL_ODR 0x1E
NilliM 0:7fa3463671dd 61 #define WOM_THR 0x1F
NilliM 0:7fa3463671dd 62
NilliM 0:7fa3463671dd 63 #define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms
NilliM 0:7fa3463671dd 64 #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]
NilliM 0:7fa3463671dd 65 #define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms
NilliM 0:7fa3463671dd 66
NilliM 0:7fa3463671dd 67 #define FIFO_EN 0x23
NilliM 0:7fa3463671dd 68 #define I2C_MST_CTRL 0x24
NilliM 0:7fa3463671dd 69 #define I2C_SLV0_ADDR 0x25
NilliM 0:7fa3463671dd 70 #define I2C_SLV0_REG 0x26
NilliM 0:7fa3463671dd 71 #define I2C_SLV0_CTRL 0x27
NilliM 0:7fa3463671dd 72 #define I2C_SLV1_ADDR 0x28
NilliM 0:7fa3463671dd 73 #define I2C_SLV1_REG 0x29
NilliM 0:7fa3463671dd 74 #define I2C_SLV1_CTRL 0x2A
NilliM 0:7fa3463671dd 75 #define I2C_SLV2_ADDR 0x2B
NilliM 0:7fa3463671dd 76 #define I2C_SLV2_REG 0x2C
NilliM 0:7fa3463671dd 77 #define I2C_SLV2_CTRL 0x2D
NilliM 0:7fa3463671dd 78 #define I2C_SLV3_ADDR 0x2E
NilliM 0:7fa3463671dd 79 #define I2C_SLV3_REG 0x2F
NilliM 0:7fa3463671dd 80 #define I2C_SLV3_CTRL 0x30
NilliM 0:7fa3463671dd 81 #define I2C_SLV4_ADDR 0x31
NilliM 0:7fa3463671dd 82 #define I2C_SLV4_REG 0x32
NilliM 0:7fa3463671dd 83 #define I2C_SLV4_DO 0x33
NilliM 0:7fa3463671dd 84 #define I2C_SLV4_CTRL 0x34
NilliM 0:7fa3463671dd 85 #define I2C_SLV4_DI 0x35
NilliM 0:7fa3463671dd 86 #define I2C_MST_STATUS 0x36
NilliM 0:7fa3463671dd 87 #define INT_PIN_CFG 0x37
NilliM 0:7fa3463671dd 88 #define INT_ENABLE 0x38
NilliM 0:7fa3463671dd 89 #define DMP_INT_STATUS 0x39 // Check DMP interrupt
NilliM 0:7fa3463671dd 90 #define INT_STATUS 0x3A
NilliM 0:7fa3463671dd 91 #define ACCEL_XOUT_H 0x3B
NilliM 0:7fa3463671dd 92 #define ACCEL_XOUT_L 0x3C
NilliM 0:7fa3463671dd 93 #define ACCEL_YOUT_H 0x3D
NilliM 0:7fa3463671dd 94 #define ACCEL_YOUT_L 0x3E
NilliM 0:7fa3463671dd 95 #define ACCEL_ZOUT_H 0x3F
NilliM 0:7fa3463671dd 96 #define ACCEL_ZOUT_L 0x40
NilliM 0:7fa3463671dd 97 #define TEMP_OUT_H 0x41
NilliM 0:7fa3463671dd 98 #define TEMP_OUT_L 0x42
NilliM 0:7fa3463671dd 99 #define GYRO_XOUT_H 0x43
NilliM 0:7fa3463671dd 100 #define GYRO_XOUT_L 0x44
NilliM 0:7fa3463671dd 101 #define GYRO_YOUT_H 0x45
NilliM 0:7fa3463671dd 102 #define GYRO_YOUT_L 0x46
NilliM 0:7fa3463671dd 103 #define GYRO_ZOUT_H 0x47
NilliM 0:7fa3463671dd 104 #define GYRO_ZOUT_L 0x48
NilliM 0:7fa3463671dd 105 #define EXT_SENS_DATA_00 0x49
NilliM 0:7fa3463671dd 106 #define EXT_SENS_DATA_01 0x4A
NilliM 0:7fa3463671dd 107 #define EXT_SENS_DATA_02 0x4B
NilliM 0:7fa3463671dd 108 #define EXT_SENS_DATA_03 0x4C
NilliM 0:7fa3463671dd 109 #define EXT_SENS_DATA_04 0x4D
NilliM 0:7fa3463671dd 110 #define EXT_SENS_DATA_05 0x4E
NilliM 0:7fa3463671dd 111 #define EXT_SENS_DATA_06 0x4F
NilliM 0:7fa3463671dd 112 #define EXT_SENS_DATA_07 0x50
NilliM 0:7fa3463671dd 113 #define EXT_SENS_DATA_08 0x51
NilliM 0:7fa3463671dd 114 #define EXT_SENS_DATA_09 0x52
NilliM 0:7fa3463671dd 115 #define EXT_SENS_DATA_10 0x53
NilliM 0:7fa3463671dd 116 #define EXT_SENS_DATA_11 0x54
NilliM 0:7fa3463671dd 117 #define EXT_SENS_DATA_12 0x55
NilliM 0:7fa3463671dd 118 #define EXT_SENS_DATA_13 0x56
NilliM 0:7fa3463671dd 119 #define EXT_SENS_DATA_14 0x57
NilliM 0:7fa3463671dd 120 #define EXT_SENS_DATA_15 0x58
NilliM 0:7fa3463671dd 121 #define EXT_SENS_DATA_16 0x59
NilliM 0:7fa3463671dd 122 #define EXT_SENS_DATA_17 0x5A
NilliM 0:7fa3463671dd 123 #define EXT_SENS_DATA_18 0x5B
NilliM 0:7fa3463671dd 124 #define EXT_SENS_DATA_19 0x5C
NilliM 0:7fa3463671dd 125 #define EXT_SENS_DATA_20 0x5D
NilliM 0:7fa3463671dd 126 #define EXT_SENS_DATA_21 0x5E
NilliM 0:7fa3463671dd 127 #define EXT_SENS_DATA_22 0x5F
NilliM 0:7fa3463671dd 128 #define EXT_SENS_DATA_23 0x60
NilliM 0:7fa3463671dd 129 #define MOT_DETECT_STATUS 0x61
NilliM 0:7fa3463671dd 130 #define I2C_SLV0_DO 0x63
NilliM 0:7fa3463671dd 131 #define I2C_SLV1_DO 0x64
NilliM 0:7fa3463671dd 132 #define I2C_SLV2_DO 0x65
NilliM 0:7fa3463671dd 133 #define I2C_SLV3_DO 0x66
NilliM 0:7fa3463671dd 134 #define I2C_MST_DELAY_CTRL 0x67
NilliM 0:7fa3463671dd 135 #define SIGNAL_PATH_RESET 0x68
NilliM 0:7fa3463671dd 136 #define MOT_DETECT_CTRL 0x69
NilliM 0:7fa3463671dd 137 #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP
NilliM 0:7fa3463671dd 138 #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode
NilliM 0:7fa3463671dd 139 #define PWR_MGMT_2 0x6C
NilliM 0:7fa3463671dd 140 #define DMP_BANK 0x6D // Activates a specific bank in the DMP
NilliM 0:7fa3463671dd 141 #define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank
NilliM 0:7fa3463671dd 142 #define DMP_REG 0x6F // Register in DMP from which to read or to which to write
NilliM 0:7fa3463671dd 143 #define DMP_REG_1 0x70
NilliM 0:7fa3463671dd 144 #define DMP_REG_2 0x71
NilliM 0:7fa3463671dd 145 #define FIFO_COUNTH 0x72
NilliM 0:7fa3463671dd 146 #define FIFO_COUNTL 0x73
NilliM 0:7fa3463671dd 147 #define FIFO_R_W 0x74
NilliM 0:7fa3463671dd 148 #define WHO_AM_I_MPU9250 0x75 // Should return 0x71
NilliM 0:7fa3463671dd 149 #define XA_OFFSET_H 0x77
NilliM 0:7fa3463671dd 150 #define XA_OFFSET_L 0x78
NilliM 0:7fa3463671dd 151 #define YA_OFFSET_H 0x7A
NilliM 0:7fa3463671dd 152 #define YA_OFFSET_L 0x7B
NilliM 0:7fa3463671dd 153 #define ZA_OFFSET_H 0x7D
NilliM 0:7fa3463671dd 154 #define ZA_OFFSET_L 0x7E
NilliM 0:7fa3463671dd 155
NilliM 0:7fa3463671dd 156 // Using the MSENSR-9250 breakout board, ADO is set to 0
NilliM 0:7fa3463671dd 157 // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1
NilliM 0:7fa3463671dd 158 //mbed uses the eight-bit device address, so shift seven-bit addresses left by one!
NilliM 0:7fa3463671dd 159 #define ADO 0
NilliM 0:7fa3463671dd 160 #if ADO
NilliM 0:7fa3463671dd 161 #define MPU9250_ADDRESS 0x69<<1 // Device address when ADO = 1
NilliM 0:7fa3463671dd 162 #else
NilliM 0:7fa3463671dd 163 #define MPU9250_ADDRESS 0x68<<1 // Device address when ADO = 0
NilliM 0:7fa3463671dd 164 #endif
NilliM 0:7fa3463671dd 165
NilliM 0:7fa3463671dd 166 // Set initial input parameters
NilliM 0:7fa3463671dd 167 enum Ascale {
NilliM 0:7fa3463671dd 168 AFS_2G = 0,
NilliM 0:7fa3463671dd 169 AFS_4G,
NilliM 0:7fa3463671dd 170 AFS_8G,
NilliM 0:7fa3463671dd 171 AFS_16G
NilliM 0:7fa3463671dd 172 };
NilliM 0:7fa3463671dd 173
NilliM 0:7fa3463671dd 174 enum Gscale {
NilliM 0:7fa3463671dd 175 GFS_250DPS = 0,
NilliM 0:7fa3463671dd 176 GFS_500DPS,
NilliM 0:7fa3463671dd 177 GFS_1000DPS,
NilliM 0:7fa3463671dd 178 GFS_2000DPS
NilliM 0:7fa3463671dd 179 };
NilliM 0:7fa3463671dd 180
NilliM 0:7fa3463671dd 181 enum Mscale {
NilliM 0:7fa3463671dd 182 MFS_14BITS = 0, // 0.6 mG per LSB
NilliM 0:7fa3463671dd 183 MFS_16BITS // 0.15 mG per LSB
NilliM 0:7fa3463671dd 184 };
NilliM 0:7fa3463671dd 185
NilliM 0:7fa3463671dd 186 uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G
NilliM 0:7fa3463671dd 187 uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS
NilliM 0:7fa3463671dd 188 uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution
NilliM 0:7fa3463671dd 189 uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR
NilliM 0:7fa3463671dd 190 float aRes, gRes, mRes; // scale resolutions per LSB for the sensors
NilliM 0:7fa3463671dd 191
NilliM 0:7fa3463671dd 192 //Set up I2C, (SDA,SCL)
NilliM 0:7fa3463671dd 193 I2C i2c(p9, p10);
NilliM 0:7fa3463671dd 194
NilliM 0:7fa3463671dd 195 DigitalOut myled(LED1);
NilliM 0:7fa3463671dd 196
NilliM 0:7fa3463671dd 197 // Pin definitions
NilliM 0:7fa3463671dd 198 int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins
NilliM 0:7fa3463671dd 199
NilliM 0:7fa3463671dd 200 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
NilliM 0:7fa3463671dd 201 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
NilliM 0:7fa3463671dd 202 int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output
NilliM 0:7fa3463671dd 203 float magCalibration[3] = {0, 0, 0}, magbias[3] = {0, 0, 0}; // Factory mag calibration and mag bias
NilliM 0:7fa3463671dd 204 float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer
NilliM 0:7fa3463671dd 205 float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
NilliM 0:7fa3463671dd 206 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
NilliM 0:7fa3463671dd 207 float temperature;
NilliM 0:7fa3463671dd 208 float SelfTest[6];
NilliM 0:7fa3463671dd 209
NilliM 0:7fa3463671dd 210 int delt_t = 0; // used to control display output rate
NilliM 0:7fa3463671dd 211 int count = 0; // used to control display output rate
NilliM 0:7fa3463671dd 212
NilliM 0:7fa3463671dd 213 // parameters for 6 DoF sensor fusion calculations
NilliM 0:7fa3463671dd 214 float PI = 3.14159265358979323846f;
NilliM 0:7fa3463671dd 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
NilliM 0:7fa3463671dd 216 float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
NilliM 0:7fa3463671dd 217 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
NilliM 0:7fa3463671dd 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
NilliM 0:7fa3463671dd 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
NilliM 0:7fa3463671dd 220 #define Ki 0.0f
NilliM 0:7fa3463671dd 221
NilliM 0:7fa3463671dd 222 float pitch, yaw, roll;
NilliM 0:7fa3463671dd 223 float deltat = 0.0f; // integration interval for both filter schemes
NilliM 0:7fa3463671dd 224 int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval
NilliM 0:7fa3463671dd 225 float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion
NilliM 0:7fa3463671dd 226 float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method
NilliM 0:7fa3463671dd 227
NilliM 0:7fa3463671dd 228 class MPU9250 {
NilliM 0:7fa3463671dd 229
NilliM 0:7fa3463671dd 230 protected:
NilliM 0:7fa3463671dd 231
NilliM 0:7fa3463671dd 232 public:
NilliM 0:7fa3463671dd 233 //===================================================================================================================
NilliM 0:7fa3463671dd 234 //====== Set of useful function to access acceleratio, gyroscope, and temperature data
NilliM 0:7fa3463671dd 235 //===================================================================================================================
NilliM 0:7fa3463671dd 236
NilliM 0:7fa3463671dd 237 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
NilliM 0:7fa3463671dd 238 {
NilliM 0:7fa3463671dd 239 char data_write[2];
NilliM 0:7fa3463671dd 240 data_write[0] = subAddress;
NilliM 0:7fa3463671dd 241 data_write[1] = data;
NilliM 0:7fa3463671dd 242 i2c.write(address, data_write, 2, 0);
NilliM 0:7fa3463671dd 243 }
NilliM 0:7fa3463671dd 244
NilliM 0:7fa3463671dd 245 char readByte(uint8_t address, uint8_t subAddress)
NilliM 0:7fa3463671dd 246 {
NilliM 0:7fa3463671dd 247 char data[1]; // `data` will store the register data
NilliM 0:7fa3463671dd 248 char data_write[1];
NilliM 0:7fa3463671dd 249 data_write[0] = subAddress;
NilliM 0:7fa3463671dd 250 i2c.write(address, data_write, 1, 1); // no stop
NilliM 0:7fa3463671dd 251 i2c.read(address, data, 1, 0);
NilliM 0:7fa3463671dd 252 return data[0];
NilliM 0:7fa3463671dd 253 }
NilliM 0:7fa3463671dd 254
NilliM 0:7fa3463671dd 255 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
NilliM 0:7fa3463671dd 256 {
NilliM 0:7fa3463671dd 257 char data[14];
NilliM 0:7fa3463671dd 258 char data_write[1];
NilliM 0:7fa3463671dd 259 data_write[0] = subAddress;
NilliM 0:7fa3463671dd 260 i2c.write(address, data_write, 1, 1); // no stop
NilliM 0:7fa3463671dd 261 i2c.read(address, data, count, 0);
NilliM 0:7fa3463671dd 262 for(int ii = 0; ii < count; ii++) {
NilliM 0:7fa3463671dd 263 dest[ii] = data[ii];
NilliM 0:7fa3463671dd 264 }
NilliM 0:7fa3463671dd 265 }
NilliM 0:7fa3463671dd 266
NilliM 0:7fa3463671dd 267
NilliM 0:7fa3463671dd 268 void getMres() {
NilliM 0:7fa3463671dd 269 switch (Mscale)
NilliM 0:7fa3463671dd 270 {
NilliM 0:7fa3463671dd 271 // Possible magnetometer scales (and their register bit settings) are:
NilliM 0:7fa3463671dd 272 // 14 bit resolution (0) and 16 bit resolution (1)
NilliM 0:7fa3463671dd 273 case MFS_14BITS:
NilliM 0:7fa3463671dd 274 mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss
NilliM 0:7fa3463671dd 275 break;
NilliM 0:7fa3463671dd 276 case MFS_16BITS:
NilliM 0:7fa3463671dd 277 mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss
NilliM 0:7fa3463671dd 278 break;
NilliM 0:7fa3463671dd 279 }
NilliM 0:7fa3463671dd 280 }
NilliM 0:7fa3463671dd 281
NilliM 0:7fa3463671dd 282
NilliM 0:7fa3463671dd 283 void getGres() {
NilliM 0:7fa3463671dd 284 switch (Gscale)
NilliM 0:7fa3463671dd 285 {
NilliM 0:7fa3463671dd 286 // Possible gyro scales (and their register bit settings) are:
NilliM 0:7fa3463671dd 287 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
NilliM 0:7fa3463671dd 288 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
NilliM 0:7fa3463671dd 289 case GFS_250DPS:
NilliM 0:7fa3463671dd 290 gRes = 250.0/32768.0;
NilliM 0:7fa3463671dd 291 break;
NilliM 0:7fa3463671dd 292 case GFS_500DPS:
NilliM 0:7fa3463671dd 293 gRes = 500.0/32768.0;
NilliM 0:7fa3463671dd 294 break;
NilliM 0:7fa3463671dd 295 case GFS_1000DPS:
NilliM 0:7fa3463671dd 296 gRes = 1000.0/32768.0;
NilliM 0:7fa3463671dd 297 break;
NilliM 0:7fa3463671dd 298 case GFS_2000DPS:
NilliM 0:7fa3463671dd 299 gRes = 2000.0/32768.0;
NilliM 0:7fa3463671dd 300 break;
NilliM 0:7fa3463671dd 301 }
NilliM 0:7fa3463671dd 302 }
NilliM 0:7fa3463671dd 303
NilliM 0:7fa3463671dd 304
NilliM 0:7fa3463671dd 305 void getAres() {
NilliM 0:7fa3463671dd 306 switch (Ascale)
NilliM 0:7fa3463671dd 307 {
NilliM 0:7fa3463671dd 308 // Possible accelerometer scales (and their register bit settings) are:
NilliM 0:7fa3463671dd 309 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
NilliM 0:7fa3463671dd 310 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
NilliM 0:7fa3463671dd 311 case AFS_2G:
NilliM 0:7fa3463671dd 312 aRes = 2.0/32768.0;
NilliM 0:7fa3463671dd 313 break;
NilliM 0:7fa3463671dd 314 case AFS_4G:
NilliM 0:7fa3463671dd 315 aRes = 4.0/32768.0;
NilliM 0:7fa3463671dd 316 break;
NilliM 0:7fa3463671dd 317 case AFS_8G:
NilliM 0:7fa3463671dd 318 aRes = 8.0/32768.0;
NilliM 0:7fa3463671dd 319 break;
NilliM 0:7fa3463671dd 320 case AFS_16G:
NilliM 0:7fa3463671dd 321 aRes = 16.0/32768.0;
NilliM 0:7fa3463671dd 322 break;
NilliM 0:7fa3463671dd 323 }
NilliM 0:7fa3463671dd 324 }
NilliM 0:7fa3463671dd 325
NilliM 0:7fa3463671dd 326
NilliM 0:7fa3463671dd 327 void readAccelData(int16_t * destination)
NilliM 0:7fa3463671dd 328 {
NilliM 0:7fa3463671dd 329 uint8_t rawData[6]; // x/y/z accel register data stored here
NilliM 0:7fa3463671dd 330 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
NilliM 0:7fa3463671dd 331 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
NilliM 0:7fa3463671dd 332 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
NilliM 0:7fa3463671dd 333 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
NilliM 0:7fa3463671dd 334 }
NilliM 0:7fa3463671dd 335
NilliM 0:7fa3463671dd 336 void readGyroData(int16_t * destination)
NilliM 0:7fa3463671dd 337 {
NilliM 0:7fa3463671dd 338 uint8_t rawData[6]; // x/y/z gyro register data stored here
NilliM 0:7fa3463671dd 339 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
NilliM 0:7fa3463671dd 340 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
NilliM 0:7fa3463671dd 341 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
NilliM 0:7fa3463671dd 342 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
NilliM 0:7fa3463671dd 343 }
NilliM 0:7fa3463671dd 344
NilliM 0:7fa3463671dd 345 void readMagData(int16_t * destination)
NilliM 0:7fa3463671dd 346 {
NilliM 0:7fa3463671dd 347 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
NilliM 0:7fa3463671dd 348 if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set
NilliM 0:7fa3463671dd 349 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
NilliM 0:7fa3463671dd 350 uint8_t c = rawData[6]; // End data read by reading ST2 register
NilliM 0:7fa3463671dd 351 if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data
NilliM 0:7fa3463671dd 352 destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value
NilliM 0:7fa3463671dd 353 destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian
NilliM 0:7fa3463671dd 354 destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ;
NilliM 0:7fa3463671dd 355 }
NilliM 0:7fa3463671dd 356 }
NilliM 0:7fa3463671dd 357 }
NilliM 0:7fa3463671dd 358
NilliM 0:7fa3463671dd 359 int16_t readTempData()
NilliM 0:7fa3463671dd 360 {
NilliM 0:7fa3463671dd 361 uint8_t rawData[2]; // x/y/z gyro register data stored here
NilliM 0:7fa3463671dd 362 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
NilliM 0:7fa3463671dd 363 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
NilliM 0:7fa3463671dd 364 }
NilliM 0:7fa3463671dd 365
NilliM 0:7fa3463671dd 366
NilliM 0:7fa3463671dd 367 void resetMPU9250() {
NilliM 0:7fa3463671dd 368 // reset device
NilliM 0:7fa3463671dd 369 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
NilliM 0:7fa3463671dd 370 wait(0.1);
NilliM 0:7fa3463671dd 371 }
NilliM 0:7fa3463671dd 372
NilliM 0:7fa3463671dd 373 void initAK8963(float * destination)
NilliM 0:7fa3463671dd 374 {
NilliM 0:7fa3463671dd 375 // First extract the factory calibration for each magnetometer axis
NilliM 0:7fa3463671dd 376 uint8_t rawData[3]; // x/y/z gyro calibration data stored here
NilliM 0:7fa3463671dd 377 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
NilliM 0:7fa3463671dd 378 wait(0.01);
NilliM 0:7fa3463671dd 379 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
NilliM 0:7fa3463671dd 380 wait(0.01);
NilliM 0:7fa3463671dd 381 readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
NilliM 0:7fa3463671dd 382 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
NilliM 0:7fa3463671dd 383 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
NilliM 0:7fa3463671dd 384 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
NilliM 0:7fa3463671dd 385 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
NilliM 0:7fa3463671dd 386 wait(0.01);
NilliM 0:7fa3463671dd 387 // Configure the magnetometer for continuous read and highest resolution
NilliM 0:7fa3463671dd 388 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
NilliM 0:7fa3463671dd 389 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
NilliM 0:7fa3463671dd 390 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
NilliM 0:7fa3463671dd 391 wait(0.01);
NilliM 0:7fa3463671dd 392 }
NilliM 0:7fa3463671dd 393
NilliM 0:7fa3463671dd 394
NilliM 0:7fa3463671dd 395 void initMPU9250()
NilliM 0:7fa3463671dd 396 {
NilliM 0:7fa3463671dd 397 // Initialize MPU9250 device
NilliM 0:7fa3463671dd 398 // wake up device
NilliM 0:7fa3463671dd 399 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
NilliM 0:7fa3463671dd 400 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
NilliM 0:7fa3463671dd 401
NilliM 0:7fa3463671dd 402 // get stable time source
NilliM 0:7fa3463671dd 403 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
NilliM 0:7fa3463671dd 404
NilliM 0:7fa3463671dd 405 // Configure Gyro and Accelerometer
NilliM 0:7fa3463671dd 406 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
NilliM 0:7fa3463671dd 407 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
NilliM 0:7fa3463671dd 408 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
NilliM 0:7fa3463671dd 409 writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
NilliM 0:7fa3463671dd 410
NilliM 0:7fa3463671dd 411 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
NilliM 0:7fa3463671dd 412 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
NilliM 0:7fa3463671dd 413
NilliM 0:7fa3463671dd 414 // Set gyroscope full scale range
NilliM 0:7fa3463671dd 415 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
NilliM 0:7fa3463671dd 416 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
NilliM 0:7fa3463671dd 417 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
NilliM 0:7fa3463671dd 418 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
NilliM 0:7fa3463671dd 419 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
NilliM 0:7fa3463671dd 420
NilliM 0:7fa3463671dd 421 // Set accelerometer configuration
NilliM 0:7fa3463671dd 422 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
NilliM 0:7fa3463671dd 423 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
NilliM 0:7fa3463671dd 424 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
NilliM 0:7fa3463671dd 425 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
NilliM 0:7fa3463671dd 426
NilliM 0:7fa3463671dd 427 // Set accelerometer sample rate configuration
NilliM 0:7fa3463671dd 428 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
NilliM 0:7fa3463671dd 429 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
NilliM 0:7fa3463671dd 430 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
NilliM 0:7fa3463671dd 431 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
NilliM 0:7fa3463671dd 432 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
NilliM 0:7fa3463671dd 433
NilliM 0:7fa3463671dd 434 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
NilliM 0:7fa3463671dd 435 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
NilliM 0:7fa3463671dd 436
NilliM 0:7fa3463671dd 437 // Configure Interrupts and Bypass Enable
NilliM 0:7fa3463671dd 438 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
NilliM 0:7fa3463671dd 439 // can join the I2C bus and all can be controlled by the Arduino as master
NilliM 0:7fa3463671dd 440 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
NilliM 0:7fa3463671dd 441 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
NilliM 0:7fa3463671dd 442 }
NilliM 0:7fa3463671dd 443
NilliM 0:7fa3463671dd 444 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
NilliM 0:7fa3463671dd 445 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
NilliM 0:7fa3463671dd 446 void calibrateMPU9250(float * dest1, float * dest2)
NilliM 0:7fa3463671dd 447 {
NilliM 0:7fa3463671dd 448 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
NilliM 0:7fa3463671dd 449 uint16_t ii, packet_count, fifo_count;
NilliM 0:7fa3463671dd 450 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
NilliM 0:7fa3463671dd 451
NilliM 0:7fa3463671dd 452 // reset device, reset all registers, clear gyro and accelerometer bias registers
NilliM 0:7fa3463671dd 453 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
NilliM 0:7fa3463671dd 454 wait(0.1);
NilliM 0:7fa3463671dd 455
NilliM 0:7fa3463671dd 456 // get stable time source
NilliM 0:7fa3463671dd 457 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
NilliM 0:7fa3463671dd 458 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
NilliM 0:7fa3463671dd 459 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
NilliM 0:7fa3463671dd 460 wait(0.2);
NilliM 0:7fa3463671dd 461
NilliM 0:7fa3463671dd 462 // Configure device for bias calculation
NilliM 0:7fa3463671dd 463 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
NilliM 0:7fa3463671dd 464 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
NilliM 0:7fa3463671dd 465 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
NilliM 0:7fa3463671dd 466 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
NilliM 0:7fa3463671dd 467 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
NilliM 0:7fa3463671dd 468 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
NilliM 0:7fa3463671dd 469 wait(0.015);
NilliM 0:7fa3463671dd 470
NilliM 0:7fa3463671dd 471 // Configure MPU9250 gyro and accelerometer for bias calculation
NilliM 0:7fa3463671dd 472 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
NilliM 0:7fa3463671dd 473 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
NilliM 0:7fa3463671dd 474 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
NilliM 0:7fa3463671dd 475 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
NilliM 0:7fa3463671dd 476
NilliM 0:7fa3463671dd 477 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
NilliM 0:7fa3463671dd 478 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
NilliM 0:7fa3463671dd 479
NilliM 0:7fa3463671dd 480 // Configure FIFO to capture accelerometer and gyro data for bias calculation
NilliM 0:7fa3463671dd 481 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
NilliM 0:7fa3463671dd 482 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
NilliM 0:7fa3463671dd 483 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
NilliM 0:7fa3463671dd 484
NilliM 0:7fa3463671dd 485 // At end of sample accumulation, turn off FIFO sensor read
NilliM 0:7fa3463671dd 486 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
NilliM 0:7fa3463671dd 487 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
NilliM 0:7fa3463671dd 488 fifo_count = ((uint16_t)data[0] << 8) | data[1];
NilliM 0:7fa3463671dd 489 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
NilliM 0:7fa3463671dd 490
NilliM 0:7fa3463671dd 491 for (ii = 0; ii < packet_count; ii++) {
NilliM 0:7fa3463671dd 492 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
NilliM 0:7fa3463671dd 493 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
NilliM 0:7fa3463671dd 494 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
NilliM 0:7fa3463671dd 495 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
NilliM 0:7fa3463671dd 496 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
NilliM 0:7fa3463671dd 497 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
NilliM 0:7fa3463671dd 498 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
NilliM 0:7fa3463671dd 499 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
NilliM 0:7fa3463671dd 500
NilliM 0:7fa3463671dd 501 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
NilliM 0:7fa3463671dd 502 accel_bias[1] += (int32_t) accel_temp[1];
NilliM 0:7fa3463671dd 503 accel_bias[2] += (int32_t) accel_temp[2];
NilliM 0:7fa3463671dd 504 gyro_bias[0] += (int32_t) gyro_temp[0];
NilliM 0:7fa3463671dd 505 gyro_bias[1] += (int32_t) gyro_temp[1];
NilliM 0:7fa3463671dd 506 gyro_bias[2] += (int32_t) gyro_temp[2];
NilliM 0:7fa3463671dd 507
NilliM 0:7fa3463671dd 508 }
NilliM 0:7fa3463671dd 509 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
NilliM 0:7fa3463671dd 510 accel_bias[1] /= (int32_t) packet_count;
NilliM 0:7fa3463671dd 511 accel_bias[2] /= (int32_t) packet_count;
NilliM 0:7fa3463671dd 512 gyro_bias[0] /= (int32_t) packet_count;
NilliM 0:7fa3463671dd 513 gyro_bias[1] /= (int32_t) packet_count;
NilliM 0:7fa3463671dd 514 gyro_bias[2] /= (int32_t) packet_count;
NilliM 0:7fa3463671dd 515
NilliM 0:7fa3463671dd 516 if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation
NilliM 0:7fa3463671dd 517 else {accel_bias[2] += (int32_t) accelsensitivity;}
NilliM 0:7fa3463671dd 518
NilliM 0:7fa3463671dd 519 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
NilliM 0:7fa3463671dd 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
NilliM 0:7fa3463671dd 521 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
NilliM 0:7fa3463671dd 522 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
NilliM 0:7fa3463671dd 523 data[3] = (-gyro_bias[1]/4) & 0xFF;
NilliM 0:7fa3463671dd 524 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
NilliM 0:7fa3463671dd 525 data[5] = (-gyro_bias[2]/4) & 0xFF;
NilliM 0:7fa3463671dd 526
NilliM 0:7fa3463671dd 527 /// Push gyro biases to hardware registers
NilliM 0:7fa3463671dd 528 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
NilliM 0:7fa3463671dd 529 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
NilliM 0:7fa3463671dd 530 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
NilliM 0:7fa3463671dd 531 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
NilliM 0:7fa3463671dd 532 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
NilliM 0:7fa3463671dd 533 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);
NilliM 0:7fa3463671dd 534 */
NilliM 0:7fa3463671dd 535 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
NilliM 0:7fa3463671dd 536 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
NilliM 0:7fa3463671dd 537 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
NilliM 0:7fa3463671dd 538
NilliM 0:7fa3463671dd 539 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
NilliM 0:7fa3463671dd 540 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
NilliM 0:7fa3463671dd 541 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
NilliM 0:7fa3463671dd 542 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
NilliM 0:7fa3463671dd 543 // the accelerometer biases calculated above must be divided by 8.
NilliM 0:7fa3463671dd 544
NilliM 0:7fa3463671dd 545 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
NilliM 0:7fa3463671dd 546 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
NilliM 0:7fa3463671dd 547 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
NilliM 0:7fa3463671dd 548 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
NilliM 0:7fa3463671dd 549 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
NilliM 0:7fa3463671dd 550 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
NilliM 0:7fa3463671dd 551 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
NilliM 0:7fa3463671dd 552
NilliM 0:7fa3463671dd 553 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
NilliM 0:7fa3463671dd 554 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
NilliM 0:7fa3463671dd 555
NilliM 0:7fa3463671dd 556 for(ii = 0; ii < 3; ii++) {
NilliM 0:7fa3463671dd 557 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
NilliM 0:7fa3463671dd 558 }
NilliM 0:7fa3463671dd 559
NilliM 0:7fa3463671dd 560 // Construct total accelerometer bias, including calculated average accelerometer bias from above
NilliM 0:7fa3463671dd 561 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
NilliM 0:7fa3463671dd 562 accel_bias_reg[1] -= (accel_bias[1]/8);
NilliM 0:7fa3463671dd 563 accel_bias_reg[2] -= (accel_bias[2]/8);
NilliM 0:7fa3463671dd 564
NilliM 0:7fa3463671dd 565 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
NilliM 0:7fa3463671dd 566 data[1] = (accel_bias_reg[0]) & 0xFF;
NilliM 0:7fa3463671dd 567 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
NilliM 0:7fa3463671dd 568 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
NilliM 0:7fa3463671dd 569 data[3] = (accel_bias_reg[1]) & 0xFF;
NilliM 0:7fa3463671dd 570 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
NilliM 0:7fa3463671dd 571 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
NilliM 0:7fa3463671dd 572 data[5] = (accel_bias_reg[2]) & 0xFF;
NilliM 0:7fa3463671dd 573 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
NilliM 0:7fa3463671dd 574
NilliM 0:7fa3463671dd 575 // Apparently this is not working for the acceleration biases in the MPU-9250
NilliM 0:7fa3463671dd 576 // Are we handling the temperature correction bit properly?
NilliM 0:7fa3463671dd 577 // Push accelerometer biases to hardware registers
NilliM 0:7fa3463671dd 578 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
NilliM 0:7fa3463671dd 579 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
NilliM 0:7fa3463671dd 580 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
NilliM 0:7fa3463671dd 581 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
NilliM 0:7fa3463671dd 582 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
NilliM 0:7fa3463671dd 583 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);
NilliM 0:7fa3463671dd 584 */
NilliM 0:7fa3463671dd 585 // Output scaled accelerometer biases for manual subtraction in the main program
NilliM 0:7fa3463671dd 586 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity;
NilliM 0:7fa3463671dd 587 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity;
NilliM 0:7fa3463671dd 588 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
NilliM 0:7fa3463671dd 589 }
NilliM 0:7fa3463671dd 590
NilliM 0:7fa3463671dd 591
NilliM 0:7fa3463671dd 592 // Accelerometer and gyroscope self test; check calibration wrt factory settings
NilliM 0:7fa3463671dd 593 void MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
NilliM 0:7fa3463671dd 594 {
NilliM 0:7fa3463671dd 595 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
NilliM 0:7fa3463671dd 596 uint8_t selfTest[6];
NilliM 0:7fa3463671dd 597 int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3];
NilliM 0:7fa3463671dd 598 float factoryTrim[6];
NilliM 0:7fa3463671dd 599 uint8_t FS = 0;
NilliM 0:7fa3463671dd 600
NilliM 0:7fa3463671dd 601 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
NilliM 0:7fa3463671dd 602 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
NilliM 0:7fa3463671dd 603 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
NilliM 0:7fa3463671dd 604 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
NilliM 0:7fa3463671dd 605 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
NilliM 0:7fa3463671dd 606
NilliM 0:7fa3463671dd 607 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
NilliM 0:7fa3463671dd 608
NilliM 0:7fa3463671dd 609 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
NilliM 0:7fa3463671dd 610 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
NilliM 0:7fa3463671dd 611 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
NilliM 0:7fa3463671dd 612 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
NilliM 0:7fa3463671dd 613
NilliM 0:7fa3463671dd 614 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
NilliM 0:7fa3463671dd 615 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
NilliM 0:7fa3463671dd 616 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
NilliM 0:7fa3463671dd 617 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
NilliM 0:7fa3463671dd 618 }
NilliM 0:7fa3463671dd 619
NilliM 0:7fa3463671dd 620 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
NilliM 0:7fa3463671dd 621 aAvg[ii] /= 200;
NilliM 0:7fa3463671dd 622 gAvg[ii] /= 200;
NilliM 0:7fa3463671dd 623 }
NilliM 0:7fa3463671dd 624
NilliM 0:7fa3463671dd 625 // Configure the accelerometer for self-test
NilliM 0:7fa3463671dd 626 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
NilliM 0:7fa3463671dd 627 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
NilliM 0:7fa3463671dd 628 wait_ms(25); // Delay a while to let the device stabilize
NilliM 0:7fa3463671dd 629
NilliM 0:7fa3463671dd 630 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
NilliM 0:7fa3463671dd 631
NilliM 0:7fa3463671dd 632 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
NilliM 0:7fa3463671dd 633 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
NilliM 0:7fa3463671dd 634 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
NilliM 0:7fa3463671dd 635 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
NilliM 0:7fa3463671dd 636
NilliM 0:7fa3463671dd 637 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
NilliM 0:7fa3463671dd 638 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
NilliM 0:7fa3463671dd 639 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
NilliM 0:7fa3463671dd 640 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
NilliM 0:7fa3463671dd 641 }
NilliM 0:7fa3463671dd 642
NilliM 0:7fa3463671dd 643 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
NilliM 0:7fa3463671dd 644 aSTAvg[ii] /= 200;
NilliM 0:7fa3463671dd 645 gSTAvg[ii] /= 200;
NilliM 0:7fa3463671dd 646 }
NilliM 0:7fa3463671dd 647
NilliM 0:7fa3463671dd 648 // Configure the gyro and accelerometer for normal operation
NilliM 0:7fa3463671dd 649 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
NilliM 0:7fa3463671dd 650 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
NilliM 0:7fa3463671dd 651 wait_ms(25); // Delay a while to let the device stabilize
NilliM 0:7fa3463671dd 652
NilliM 0:7fa3463671dd 653 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
NilliM 0:7fa3463671dd 654 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
NilliM 0:7fa3463671dd 655 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
NilliM 0:7fa3463671dd 656 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
NilliM 0:7fa3463671dd 657 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
NilliM 0:7fa3463671dd 658 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
NilliM 0:7fa3463671dd 659 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
NilliM 0:7fa3463671dd 660
NilliM 0:7fa3463671dd 661 // Retrieve factory self-test value from self-test code reads
NilliM 0:7fa3463671dd 662 factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation
NilliM 0:7fa3463671dd 663 factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation
NilliM 0:7fa3463671dd 664 factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation
NilliM 0:7fa3463671dd 665 factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation
NilliM 0:7fa3463671dd 666 factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation
NilliM 0:7fa3463671dd 667 factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation
NilliM 0:7fa3463671dd 668
NilliM 0:7fa3463671dd 669 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
NilliM 0:7fa3463671dd 670 // To get percent, must multiply by 100
NilliM 0:7fa3463671dd 671 for (int i = 0; i < 3; i++) {
NilliM 0:7fa3463671dd 672 destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences
NilliM 0:7fa3463671dd 673 destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences
NilliM 0:7fa3463671dd 674 }
NilliM 0:7fa3463671dd 675
NilliM 0:7fa3463671dd 676 }
NilliM 0:7fa3463671dd 677
NilliM 0:7fa3463671dd 678
NilliM 0:7fa3463671dd 679
NilliM 0:7fa3463671dd 680 // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
NilliM 0:7fa3463671dd 681 // (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
NilliM 0:7fa3463671dd 682 // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute
NilliM 0:7fa3463671dd 683 // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
NilliM 0:7fa3463671dd 684 // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
NilliM 0:7fa3463671dd 685 // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
NilliM 0:7fa3463671dd 686 void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
NilliM 0:7fa3463671dd 687 {
NilliM 0:7fa3463671dd 688 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
NilliM 0:7fa3463671dd 689 float norm;
NilliM 0:7fa3463671dd 690 float hx, hy, _2bx, _2bz;
NilliM 0:7fa3463671dd 691 float s1, s2, s3, s4;
NilliM 0:7fa3463671dd 692 float qDot1, qDot2, qDot3, qDot4;
NilliM 0:7fa3463671dd 693
NilliM 0:7fa3463671dd 694 // Auxiliary variables to avoid repeated arithmetic
NilliM 0:7fa3463671dd 695 float _2q1mx;
NilliM 0:7fa3463671dd 696 float _2q1my;
NilliM 0:7fa3463671dd 697 float _2q1mz;
NilliM 0:7fa3463671dd 698 float _2q2mx;
NilliM 0:7fa3463671dd 699 float _4bx;
NilliM 0:7fa3463671dd 700 float _4bz;
NilliM 0:7fa3463671dd 701 float _2q1 = 2.0f * q1;
NilliM 0:7fa3463671dd 702 float _2q2 = 2.0f * q2;
NilliM 0:7fa3463671dd 703 float _2q3 = 2.0f * q3;
NilliM 0:7fa3463671dd 704 float _2q4 = 2.0f * q4;
NilliM 0:7fa3463671dd 705 float _2q1q3 = 2.0f * q1 * q3;
NilliM 0:7fa3463671dd 706 float _2q3q4 = 2.0f * q3 * q4;
NilliM 0:7fa3463671dd 707 float q1q1 = q1 * q1;
NilliM 0:7fa3463671dd 708 float q1q2 = q1 * q2;
NilliM 0:7fa3463671dd 709 float q1q3 = q1 * q3;
NilliM 0:7fa3463671dd 710 float q1q4 = q1 * q4;
NilliM 0:7fa3463671dd 711 float q2q2 = q2 * q2;
NilliM 0:7fa3463671dd 712 float q2q3 = q2 * q3;
NilliM 0:7fa3463671dd 713 float q2q4 = q2 * q4;
NilliM 0:7fa3463671dd 714 float q3q3 = q3 * q3;
NilliM 0:7fa3463671dd 715 float q3q4 = q3 * q4;
NilliM 0:7fa3463671dd 716 float q4q4 = q4 * q4;
NilliM 0:7fa3463671dd 717
NilliM 0:7fa3463671dd 718 // Normalise accelerometer measurement
NilliM 0:7fa3463671dd 719 norm = sqrt(ax * ax + ay * ay + az * az);
NilliM 0:7fa3463671dd 720 if (norm == 0.0f) return; // handle NaN
NilliM 0:7fa3463671dd 721 norm = 1.0f/norm;
NilliM 0:7fa3463671dd 722 ax *= norm;
NilliM 0:7fa3463671dd 723 ay *= norm;
NilliM 0:7fa3463671dd 724 az *= norm;
NilliM 0:7fa3463671dd 725
NilliM 0:7fa3463671dd 726 // Normalise magnetometer measurement
NilliM 0:7fa3463671dd 727 norm = sqrt(mx * mx + my * my + mz * mz);
NilliM 0:7fa3463671dd 728 if (norm == 0.0f) return; // handle NaN
NilliM 0:7fa3463671dd 729 norm = 1.0f/norm;
NilliM 0:7fa3463671dd 730 mx *= norm;
NilliM 0:7fa3463671dd 731 my *= norm;
NilliM 0:7fa3463671dd 732 mz *= norm;
NilliM 0:7fa3463671dd 733
NilliM 0:7fa3463671dd 734 // Reference direction of Earth's magnetic field
NilliM 0:7fa3463671dd 735 _2q1mx = 2.0f * q1 * mx;
NilliM 0:7fa3463671dd 736 _2q1my = 2.0f * q1 * my;
NilliM 0:7fa3463671dd 737 _2q1mz = 2.0f * q1 * mz;
NilliM 0:7fa3463671dd 738 _2q2mx = 2.0f * q2 * mx;
NilliM 0:7fa3463671dd 739 hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4;
NilliM 0:7fa3463671dd 740 hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4;
NilliM 0:7fa3463671dd 741 _2bx = sqrt(hx * hx + hy * hy);
NilliM 0:7fa3463671dd 742 _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4;
NilliM 0:7fa3463671dd 743 _4bx = 2.0f * _2bx;
NilliM 0:7fa3463671dd 744 _4bz = 2.0f * _2bz;
NilliM 0:7fa3463671dd 745
NilliM 0:7fa3463671dd 746 // Gradient decent algorithm corrective step
NilliM 0:7fa3463671dd 747 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);
NilliM 0:7fa3463671dd 748 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);
NilliM 0:7fa3463671dd 749 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);
NilliM 0:7fa3463671dd 750 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);
NilliM 0:7fa3463671dd 751 norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude
NilliM 0:7fa3463671dd 752 norm = 1.0f/norm;
NilliM 0:7fa3463671dd 753 s1 *= norm;
NilliM 0:7fa3463671dd 754 s2 *= norm;
NilliM 0:7fa3463671dd 755 s3 *= norm;
NilliM 0:7fa3463671dd 756 s4 *= norm;
NilliM 0:7fa3463671dd 757
NilliM 0:7fa3463671dd 758 // Compute rate of change of quaternion
NilliM 0:7fa3463671dd 759 qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1;
NilliM 0:7fa3463671dd 760 qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2;
NilliM 0:7fa3463671dd 761 qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3;
NilliM 0:7fa3463671dd 762 qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4;
NilliM 0:7fa3463671dd 763
NilliM 0:7fa3463671dd 764 // Integrate to yield quaternion
NilliM 0:7fa3463671dd 765 q1 += qDot1 * deltat;
NilliM 0:7fa3463671dd 766 q2 += qDot2 * deltat;
NilliM 0:7fa3463671dd 767 q3 += qDot3 * deltat;
NilliM 0:7fa3463671dd 768 q4 += qDot4 * deltat;
NilliM 0:7fa3463671dd 769 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
NilliM 0:7fa3463671dd 770 norm = 1.0f/norm;
NilliM 0:7fa3463671dd 771 q[0] = q1 * norm;
NilliM 0:7fa3463671dd 772 q[1] = q2 * norm;
NilliM 0:7fa3463671dd 773 q[2] = q3 * norm;
NilliM 0:7fa3463671dd 774 q[3] = q4 * norm;
NilliM 0:7fa3463671dd 775
NilliM 0:7fa3463671dd 776 }
NilliM 0:7fa3463671dd 777
NilliM 0:7fa3463671dd 778
NilliM 0:7fa3463671dd 779
NilliM 0:7fa3463671dd 780 // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and
NilliM 0:7fa3463671dd 781 // measured ones.
NilliM 0:7fa3463671dd 782 void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
NilliM 0:7fa3463671dd 783 {
NilliM 0:7fa3463671dd 784 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
NilliM 0:7fa3463671dd 785 float norm;
NilliM 0:7fa3463671dd 786 float hx, hy, bx, bz;
NilliM 0:7fa3463671dd 787 float vx, vy, vz, wx, wy, wz;
NilliM 0:7fa3463671dd 788 float ex, ey, ez;
NilliM 0:7fa3463671dd 789 float pa, pb, pc;
NilliM 0:7fa3463671dd 790
NilliM 0:7fa3463671dd 791 // Auxiliary variables to avoid repeated arithmetic
NilliM 0:7fa3463671dd 792 float q1q1 = q1 * q1;
NilliM 0:7fa3463671dd 793 float q1q2 = q1 * q2;
NilliM 0:7fa3463671dd 794 float q1q3 = q1 * q3;
NilliM 0:7fa3463671dd 795 float q1q4 = q1 * q4;
NilliM 0:7fa3463671dd 796 float q2q2 = q2 * q2;
NilliM 0:7fa3463671dd 797 float q2q3 = q2 * q3;
NilliM 0:7fa3463671dd 798 float q2q4 = q2 * q4;
NilliM 0:7fa3463671dd 799 float q3q3 = q3 * q3;
NilliM 0:7fa3463671dd 800 float q3q4 = q3 * q4;
NilliM 0:7fa3463671dd 801 float q4q4 = q4 * q4;
NilliM 0:7fa3463671dd 802
NilliM 0:7fa3463671dd 803 // Normalise accelerometer measurement
NilliM 0:7fa3463671dd 804 norm = sqrt(ax * ax + ay * ay + az * az);
NilliM 0:7fa3463671dd 805 if (norm == 0.0f) return; // handle NaN
NilliM 0:7fa3463671dd 806 norm = 1.0f / norm; // use reciprocal for division
NilliM 0:7fa3463671dd 807 ax *= norm;
NilliM 0:7fa3463671dd 808 ay *= norm;
NilliM 0:7fa3463671dd 809 az *= norm;
NilliM 0:7fa3463671dd 810
NilliM 0:7fa3463671dd 811 // Normalise magnetometer measurement
NilliM 0:7fa3463671dd 812 norm = sqrt(mx * mx + my * my + mz * mz);
NilliM 0:7fa3463671dd 813 if (norm == 0.0f) return; // handle NaN
NilliM 0:7fa3463671dd 814 norm = 1.0f / norm; // use reciprocal for division
NilliM 0:7fa3463671dd 815 mx *= norm;
NilliM 0:7fa3463671dd 816 my *= norm;
NilliM 0:7fa3463671dd 817 mz *= norm;
NilliM 0:7fa3463671dd 818
NilliM 0:7fa3463671dd 819 // Reference direction of Earth's magnetic field
NilliM 0:7fa3463671dd 820 hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3);
NilliM 0:7fa3463671dd 821 hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2);
NilliM 0:7fa3463671dd 822 bx = sqrt((hx * hx) + (hy * hy));
NilliM 0:7fa3463671dd 823 bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3);
NilliM 0:7fa3463671dd 824
NilliM 0:7fa3463671dd 825 // Estimated direction of gravity and magnetic field
NilliM 0:7fa3463671dd 826 vx = 2.0f * (q2q4 - q1q3);
NilliM 0:7fa3463671dd 827 vy = 2.0f * (q1q2 + q3q4);
NilliM 0:7fa3463671dd 828 vz = q1q1 - q2q2 - q3q3 + q4q4;
NilliM 0:7fa3463671dd 829 wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3);
NilliM 0:7fa3463671dd 830 wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4);
NilliM 0:7fa3463671dd 831 wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3);
NilliM 0:7fa3463671dd 832
NilliM 0:7fa3463671dd 833 // Error is cross product between estimated direction and measured direction of gravity
NilliM 0:7fa3463671dd 834 ex = (ay * vz - az * vy) + (my * wz - mz * wy);
NilliM 0:7fa3463671dd 835 ey = (az * vx - ax * vz) + (mz * wx - mx * wz);
NilliM 0:7fa3463671dd 836 ez = (ax * vy - ay * vx) + (mx * wy - my * wx);
NilliM 0:7fa3463671dd 837 if (Ki > 0.0f)
NilliM 0:7fa3463671dd 838 {
NilliM 0:7fa3463671dd 839 eInt[0] += ex; // accumulate integral error
NilliM 0:7fa3463671dd 840 eInt[1] += ey;
NilliM 0:7fa3463671dd 841 eInt[2] += ez;
NilliM 0:7fa3463671dd 842 }
NilliM 0:7fa3463671dd 843 else
NilliM 0:7fa3463671dd 844 {
NilliM 0:7fa3463671dd 845 eInt[0] = 0.0f; // prevent integral wind up
NilliM 0:7fa3463671dd 846 eInt[1] = 0.0f;
NilliM 0:7fa3463671dd 847 eInt[2] = 0.0f;
NilliM 0:7fa3463671dd 848 }
NilliM 0:7fa3463671dd 849
NilliM 0:7fa3463671dd 850 // Apply feedback terms
NilliM 0:7fa3463671dd 851 gx = gx + Kp * ex + Ki * eInt[0];
NilliM 0:7fa3463671dd 852 gy = gy + Kp * ey + Ki * eInt[1];
NilliM 0:7fa3463671dd 853 gz = gz + Kp * ez + Ki * eInt[2];
NilliM 0:7fa3463671dd 854
NilliM 0:7fa3463671dd 855 // Integrate rate of change of quaternion
NilliM 0:7fa3463671dd 856 pa = q2;
NilliM 0:7fa3463671dd 857 pb = q3;
NilliM 0:7fa3463671dd 858 pc = q4;
NilliM 0:7fa3463671dd 859 q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat);
NilliM 0:7fa3463671dd 860 q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat);
NilliM 0:7fa3463671dd 861 q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat);
NilliM 0:7fa3463671dd 862 q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat);
NilliM 0:7fa3463671dd 863
NilliM 0:7fa3463671dd 864 // Normalise quaternion
NilliM 0:7fa3463671dd 865 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);
NilliM 0:7fa3463671dd 866 norm = 1.0f / norm;
NilliM 0:7fa3463671dd 867 q[0] = q1 * norm;
NilliM 0:7fa3463671dd 868 q[1] = q2 * norm;
NilliM 0:7fa3463671dd 869 q[2] = q3 * norm;
NilliM 0:7fa3463671dd 870 q[3] = q4 * norm;
NilliM 0:7fa3463671dd 871
NilliM 0:7fa3463671dd 872 }
NilliM 0:7fa3463671dd 873 };
NilliM 0:7fa3463671dd 874 #endif