TurtleBot / Mbed 2 deprecated Pre-hormone

Pre-test

Dependencies:   LinkedList mbed-rtos mbed

MPU9250.h@0:d98bd8b7dc46, 2018-04-09 (annotated)

Committer:
Khanchana
Date:
Mon Apr 09 15:57:36 2018 +0000
Revision:
0:d98bd8b7dc46
Pre-test

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Khanchana 0:d98bd8b7dc46 1 #ifndef MPU9250_H
Khanchana 0:d98bd8b7dc46 2 #define MPU9250_H
Khanchana 0:d98bd8b7dc46 3
Khanchana 0:d98bd8b7dc46 4 #include "mbed.h"
Khanchana 0:d98bd8b7dc46 5 #include "math.h"
Khanchana 0:d98bd8b7dc46 6
Khanchana 0:d98bd8b7dc46 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
Khanchana 0:d98bd8b7dc46 8 // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map
Khanchana 0:d98bd8b7dc46 9 //
Khanchana 0:d98bd8b7dc46 10 //Magnetometer Registers
Khanchana 0:d98bd8b7dc46 11 #define AK8963_ADDRESS 0x0C<<1
Khanchana 0:d98bd8b7dc46 12 #define WHO_AM_I_AK8963 0x00 // should return 0x48
Khanchana 0:d98bd8b7dc46 13 #define INFO 0x01
Khanchana 0:d98bd8b7dc46 14 #define AK8963_ST1 0x02 // data ready status bit 0
Khanchana 0:d98bd8b7dc46 15 #define AK8963_XOUT_L 0x03 // data
Khanchana 0:d98bd8b7dc46 16 #define AK8963_XOUT_H 0x04
Khanchana 0:d98bd8b7dc46 17 #define AK8963_YOUT_L 0x05
Khanchana 0:d98bd8b7dc46 18 #define AK8963_YOUT_H 0x06
Khanchana 0:d98bd8b7dc46 19 #define AK8963_ZOUT_L 0x07
Khanchana 0:d98bd8b7dc46 20 #define AK8963_ZOUT_H 0x08
Khanchana 0:d98bd8b7dc46 21 #define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status bit 2
Khanchana 0:d98bd8b7dc46 22 #define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001), self-test (1000) and Fuse ROM (1111) modes on bits 3:0
Khanchana 0:d98bd8b7dc46 23 #define AK8963_ASTC 0x0C // Self test control
Khanchana 0:d98bd8b7dc46 24 #define AK8963_I2CDIS 0x0F // I2C disable
Khanchana 0:d98bd8b7dc46 25 #define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value
Khanchana 0:d98bd8b7dc46 26 #define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value
Khanchana 0:d98bd8b7dc46 27 #define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value
Khanchana 0:d98bd8b7dc46 28
Khanchana 0:d98bd8b7dc46 29 #define SELF_TEST_X_GYRO 0x00
Khanchana 0:d98bd8b7dc46 30 #define SELF_TEST_Y_GYRO 0x01
Khanchana 0:d98bd8b7dc46 31 #define SELF_TEST_Z_GYRO 0x02
Khanchana 0:d98bd8b7dc46 32
Khanchana 0:d98bd8b7dc46 33 /*#define X_FINE_GAIN 0x03 // [7:0] fine gain
Khanchana 0:d98bd8b7dc46 34 #define Y_FINE_GAIN 0x04
Khanchana 0:d98bd8b7dc46 35 #define Z_FINE_GAIN 0x05
Khanchana 0:d98bd8b7dc46 36 #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer
Khanchana 0:d98bd8b7dc46 37 #define XA_OFFSET_L_TC 0x07
Khanchana 0:d98bd8b7dc46 38 #define YA_OFFSET_H 0x08
Khanchana 0:d98bd8b7dc46 39 #define YA_OFFSET_L_TC 0x09
Khanchana 0:d98bd8b7dc46 40 #define ZA_OFFSET_H 0x0A
Khanchana 0:d98bd8b7dc46 41 #define ZA_OFFSET_L_TC 0x0B */
Khanchana 0:d98bd8b7dc46 42
Khanchana 0:d98bd8b7dc46 43 #define SELF_TEST_X_ACCEL 0x0D
Khanchana 0:d98bd8b7dc46 44 #define SELF_TEST_Y_ACCEL 0x0E
Khanchana 0:d98bd8b7dc46 45 #define SELF_TEST_Z_ACCEL 0x0F
Khanchana 0:d98bd8b7dc46 46
Khanchana 0:d98bd8b7dc46 47 #define SELF_TEST_A 0x10
Khanchana 0:d98bd8b7dc46 48
Khanchana 0:d98bd8b7dc46 49 #define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope
Khanchana 0:d98bd8b7dc46 50 #define XG_OFFSET_L 0x14
Khanchana 0:d98bd8b7dc46 51 #define YG_OFFSET_H 0x15
Khanchana 0:d98bd8b7dc46 52 #define YG_OFFSET_L 0x16
Khanchana 0:d98bd8b7dc46 53 #define ZG_OFFSET_H 0x17
Khanchana 0:d98bd8b7dc46 54 #define ZG_OFFSET_L 0x18
Khanchana 0:d98bd8b7dc46 55 #define SMPLRT_DIV 0x19
Khanchana 0:d98bd8b7dc46 56 #define CONFIG 0x1A
Khanchana 0:d98bd8b7dc46 57 #define GYRO_CONFIG 0x1B
Khanchana 0:d98bd8b7dc46 58 #define ACCEL_CONFIG 0x1C
Khanchana 0:d98bd8b7dc46 59 #define ACCEL_CONFIG2 0x1D
Khanchana 0:d98bd8b7dc46 60 #define LP_ACCEL_ODR 0x1E
Khanchana 0:d98bd8b7dc46 61 #define WOM_THR 0x1F
Khanchana 0:d98bd8b7dc46 62
Khanchana 0:d98bd8b7dc46 63 #define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms
Khanchana 0:d98bd8b7dc46 64 #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]
Khanchana 0:d98bd8b7dc46 65 #define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms
Khanchana 0:d98bd8b7dc46 66
Khanchana 0:d98bd8b7dc46 67 #define FIFO_EN 0x23
Khanchana 0:d98bd8b7dc46 68 #define I2C_MST_CTRL 0x24
Khanchana 0:d98bd8b7dc46 69 #define I2C_SLV0_ADDR 0x25
Khanchana 0:d98bd8b7dc46 70 #define I2C_SLV0_REG 0x26
Khanchana 0:d98bd8b7dc46 71 #define I2C_SLV0_CTRL 0x27
Khanchana 0:d98bd8b7dc46 72 #define I2C_SLV1_ADDR 0x28
Khanchana 0:d98bd8b7dc46 73 #define I2C_SLV1_REG 0x29
Khanchana 0:d98bd8b7dc46 74 #define I2C_SLV1_CTRL 0x2A
Khanchana 0:d98bd8b7dc46 75 #define I2C_SLV2_ADDR 0x2B
Khanchana 0:d98bd8b7dc46 76 #define I2C_SLV2_REG 0x2C
Khanchana 0:d98bd8b7dc46 77 #define I2C_SLV2_CTRL 0x2D
Khanchana 0:d98bd8b7dc46 78 #define I2C_SLV3_ADDR 0x2E
Khanchana 0:d98bd8b7dc46 79 #define I2C_SLV3_REG 0x2F
Khanchana 0:d98bd8b7dc46 80 #define I2C_SLV3_CTRL 0x30
Khanchana 0:d98bd8b7dc46 81 #define I2C_SLV4_ADDR 0x31
Khanchana 0:d98bd8b7dc46 82 #define I2C_SLV4_REG 0x32
Khanchana 0:d98bd8b7dc46 83 #define I2C_SLV4_DO 0x33
Khanchana 0:d98bd8b7dc46 84 #define I2C_SLV4_CTRL 0x34
Khanchana 0:d98bd8b7dc46 85 #define I2C_SLV4_DI 0x35
Khanchana 0:d98bd8b7dc46 86 #define I2C_MST_STATUS 0x36
Khanchana 0:d98bd8b7dc46 87 #define INT_PIN_CFG 0x37
Khanchana 0:d98bd8b7dc46 88 #define INT_ENABLE 0x38
Khanchana 0:d98bd8b7dc46 89 #define DMP_INT_STATUS 0x39 // Check DMP interrupt
Khanchana 0:d98bd8b7dc46 90 #define INT_STATUS 0x3A
Khanchana 0:d98bd8b7dc46 91 #define ACCEL_XOUT_H 0x3B
Khanchana 0:d98bd8b7dc46 92 #define ACCEL_XOUT_L 0x3C
Khanchana 0:d98bd8b7dc46 93 #define ACCEL_YOUT_H 0x3D
Khanchana 0:d98bd8b7dc46 94 #define ACCEL_YOUT_L 0x3E
Khanchana 0:d98bd8b7dc46 95 #define ACCEL_ZOUT_H 0x3F
Khanchana 0:d98bd8b7dc46 96 #define ACCEL_ZOUT_L 0x40
Khanchana 0:d98bd8b7dc46 97 #define TEMP_OUT_H 0x41
Khanchana 0:d98bd8b7dc46 98 #define TEMP_OUT_L 0x42
Khanchana 0:d98bd8b7dc46 99 #define GYRO_XOUT_H 0x43
Khanchana 0:d98bd8b7dc46 100 #define GYRO_XOUT_L 0x44
Khanchana 0:d98bd8b7dc46 101 #define GYRO_YOUT_H 0x45
Khanchana 0:d98bd8b7dc46 102 #define GYRO_YOUT_L 0x46
Khanchana 0:d98bd8b7dc46 103 #define GYRO_ZOUT_H 0x47
Khanchana 0:d98bd8b7dc46 104 #define GYRO_ZOUT_L 0x48
Khanchana 0:d98bd8b7dc46 105 #define EXT_SENS_DATA_00 0x49
Khanchana 0:d98bd8b7dc46 106 #define EXT_SENS_DATA_01 0x4A
Khanchana 0:d98bd8b7dc46 107 #define EXT_SENS_DATA_02 0x4B
Khanchana 0:d98bd8b7dc46 108 #define EXT_SENS_DATA_03 0x4C
Khanchana 0:d98bd8b7dc46 109 #define EXT_SENS_DATA_04 0x4D
Khanchana 0:d98bd8b7dc46 110 #define EXT_SENS_DATA_05 0x4E
Khanchana 0:d98bd8b7dc46 111 #define EXT_SENS_DATA_06 0x4F
Khanchana 0:d98bd8b7dc46 112 #define EXT_SENS_DATA_07 0x50
Khanchana 0:d98bd8b7dc46 113 #define EXT_SENS_DATA_08 0x51
Khanchana 0:d98bd8b7dc46 114 #define EXT_SENS_DATA_09 0x52
Khanchana 0:d98bd8b7dc46 115 #define EXT_SENS_DATA_10 0x53
Khanchana 0:d98bd8b7dc46 116 #define EXT_SENS_DATA_11 0x54
Khanchana 0:d98bd8b7dc46 117 #define EXT_SENS_DATA_12 0x55
Khanchana 0:d98bd8b7dc46 118 #define EXT_SENS_DATA_13 0x56
Khanchana 0:d98bd8b7dc46 119 #define EXT_SENS_DATA_14 0x57
Khanchana 0:d98bd8b7dc46 120 #define EXT_SENS_DATA_15 0x58
Khanchana 0:d98bd8b7dc46 121 #define EXT_SENS_DATA_16 0x59
Khanchana 0:d98bd8b7dc46 122 #define EXT_SENS_DATA_17 0x5A
Khanchana 0:d98bd8b7dc46 123 #define EXT_SENS_DATA_18 0x5B
Khanchana 0:d98bd8b7dc46 124 #define EXT_SENS_DATA_19 0x5C
Khanchana 0:d98bd8b7dc46 125 #define EXT_SENS_DATA_20 0x5D
Khanchana 0:d98bd8b7dc46 126 #define EXT_SENS_DATA_21 0x5E
Khanchana 0:d98bd8b7dc46 127 #define EXT_SENS_DATA_22 0x5F
Khanchana 0:d98bd8b7dc46 128 #define EXT_SENS_DATA_23 0x60
Khanchana 0:d98bd8b7dc46 129 #define MOT_DETECT_STATUS 0x61
Khanchana 0:d98bd8b7dc46 130 #define I2C_SLV0_DO 0x63
Khanchana 0:d98bd8b7dc46 131 #define I2C_SLV1_DO 0x64
Khanchana 0:d98bd8b7dc46 132 #define I2C_SLV2_DO 0x65
Khanchana 0:d98bd8b7dc46 133 #define I2C_SLV3_DO 0x66
Khanchana 0:d98bd8b7dc46 134 #define I2C_MST_DELAY_CTRL 0x67
Khanchana 0:d98bd8b7dc46 135 #define SIGNAL_PATH_RESET 0x68
Khanchana 0:d98bd8b7dc46 136 #define MOT_DETECT_CTRL 0x69
Khanchana 0:d98bd8b7dc46 137 #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP
Khanchana 0:d98bd8b7dc46 138 #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode
Khanchana 0:d98bd8b7dc46 139 #define PWR_MGMT_2 0x6C
Khanchana 0:d98bd8b7dc46 140 #define DMP_BANK 0x6D // Activates a specific bank in the DMP
Khanchana 0:d98bd8b7dc46 141 #define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank
Khanchana 0:d98bd8b7dc46 142 #define DMP_REG 0x6F // Register in DMP from which to read or to which to write
Khanchana 0:d98bd8b7dc46 143 #define DMP_REG_1 0x70
Khanchana 0:d98bd8b7dc46 144 #define DMP_REG_2 0x71
Khanchana 0:d98bd8b7dc46 145 #define FIFO_COUNTH 0x72
Khanchana 0:d98bd8b7dc46 146 #define FIFO_COUNTL 0x73
Khanchana 0:d98bd8b7dc46 147 #define FIFO_R_W 0x74
Khanchana 0:d98bd8b7dc46 148 #define WHO_AM_I_MPU9250 0x75 // Should return 0x71
Khanchana 0:d98bd8b7dc46 149 #define XA_OFFSET_H 0x77
Khanchana 0:d98bd8b7dc46 150 #define XA_OFFSET_L 0x78
Khanchana 0:d98bd8b7dc46 151 #define YA_OFFSET_H 0x7A
Khanchana 0:d98bd8b7dc46 152 #define YA_OFFSET_L 0x7B
Khanchana 0:d98bd8b7dc46 153 #define ZA_OFFSET_H 0x7D
Khanchana 0:d98bd8b7dc46 154 #define ZA_OFFSET_L 0x7E
Khanchana 0:d98bd8b7dc46 155
Khanchana 0:d98bd8b7dc46 156 // Using the MSENSR-9250 breakout board, ADO is set to 0
Khanchana 0:d98bd8b7dc46 157 // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1
Khanchana 0:d98bd8b7dc46 158 //mbed uses the eight-bit device address, so shift seven-bit addresses left by one!
Khanchana 0:d98bd8b7dc46 159 #define ADO 0
Khanchana 0:d98bd8b7dc46 160 #if ADO
Khanchana 0:d98bd8b7dc46 161 #define MPU9250_ADDRESS 0x69<<1 // Device address when ADO = 1
Khanchana 0:d98bd8b7dc46 162 #else
Khanchana 0:d98bd8b7dc46 163 #define MPU9250_ADDRESS 0x68<<1 // Device address when ADO = 0
Khanchana 0:d98bd8b7dc46 164 #endif
Khanchana 0:d98bd8b7dc46 165
Khanchana 0:d98bd8b7dc46 166 // Set initial input parameters
Khanchana 0:d98bd8b7dc46 167 enum Ascale {
Khanchana 0:d98bd8b7dc46 168 AFS_2G = 0,
Khanchana 0:d98bd8b7dc46 169 AFS_4G,
Khanchana 0:d98bd8b7dc46 170 AFS_8G,
Khanchana 0:d98bd8b7dc46 171 AFS_16G
Khanchana 0:d98bd8b7dc46 172 };
Khanchana 0:d98bd8b7dc46 173
Khanchana 0:d98bd8b7dc46 174 enum Gscale {
Khanchana 0:d98bd8b7dc46 175 GFS_250DPS = 0,
Khanchana 0:d98bd8b7dc46 176 GFS_500DPS,
Khanchana 0:d98bd8b7dc46 177 GFS_1000DPS,
Khanchana 0:d98bd8b7dc46 178 GFS_2000DPS
Khanchana 0:d98bd8b7dc46 179 };
Khanchana 0:d98bd8b7dc46 180
Khanchana 0:d98bd8b7dc46 181 enum Mscale {
Khanchana 0:d98bd8b7dc46 182 MFS_14BITS = 0, // 0.6 mG per LSB
Khanchana 0:d98bd8b7dc46 183 MFS_16BITS // 0.15 mG per LSB
Khanchana 0:d98bd8b7dc46 184 };
Khanchana 0:d98bd8b7dc46 185
Khanchana 0:d98bd8b7dc46 186 uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G
Khanchana 0:d98bd8b7dc46 187 uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS
Khanchana 0:d98bd8b7dc46 188 uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution
Khanchana 0:d98bd8b7dc46 189 uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR
Khanchana 0:d98bd8b7dc46 190 float aRes, gRes, mRes; // scale resolutions per LSB for the sensors
Khanchana 0:d98bd8b7dc46 191
Khanchana 0:d98bd8b7dc46 192 //Set up I2C, (SDA,SCL)
Khanchana 0:d98bd8b7dc46 193 I2C i2c(I2C_SDA, I2C_SCL);
Khanchana 0:d98bd8b7dc46 194
Khanchana 0:d98bd8b7dc46 195 DigitalOut myled(LED1);
Khanchana 0:d98bd8b7dc46 196
Khanchana 0:d98bd8b7dc46 197 // Pin definitions
Khanchana 0:d98bd8b7dc46 198 int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins
Khanchana 0:d98bd8b7dc46 199
Khanchana 0:d98bd8b7dc46 200 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
Khanchana 0:d98bd8b7dc46 201 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
Khanchana 0:d98bd8b7dc46 202 int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output
Khanchana 0:d98bd8b7dc46 203 float magCalibration[3] = {0, 0, 0}, magbias[3] = {0, 0, 0}; // Factory mag calibration and mag bias
Khanchana 0:d98bd8b7dc46 204 float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer
Khanchana 0:d98bd8b7dc46 205 float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
Khanchana 0:d98bd8b7dc46 206 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
Khanchana 0:d98bd8b7dc46 207 float temperature;
Khanchana 0:d98bd8b7dc46 208 float SelfTest[6];
Khanchana 0:d98bd8b7dc46 209
Khanchana 0:d98bd8b7dc46 210 int delt_t = 0; // used to control display output rate
Khanchana 0:d98bd8b7dc46 211 int count = 0; // used to control display output rate
Khanchana 0:d98bd8b7dc46 212
Khanchana 0:d98bd8b7dc46 213 // parameters for 6 DoF sensor fusion calculations
Khanchana 0:d98bd8b7dc46 214 float PI = 3.14159265358979323846f;
Khanchana 0:d98bd8b7dc46 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
Khanchana 0:d98bd8b7dc46 216 float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
Khanchana 0:d98bd8b7dc46 217 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
Khanchana 0:d98bd8b7dc46 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
Khanchana 0:d98bd8b7dc46 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
Khanchana 0:d98bd8b7dc46 220 #define Ki 0.0f
Khanchana 0:d98bd8b7dc46 221
Khanchana 0:d98bd8b7dc46 222 float pitch, yaw, roll;
Khanchana 0:d98bd8b7dc46 223 float deltat = 0.0f; // integration interval for both filter schemes
Khanchana 0:d98bd8b7dc46 224 int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval
Khanchana 0:d98bd8b7dc46 225 float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion
Khanchana 0:d98bd8b7dc46 226 float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method
Khanchana 0:d98bd8b7dc46 227
Khanchana 0:d98bd8b7dc46 228 class MPU9250 {
Khanchana 0:d98bd8b7dc46 229
Khanchana 0:d98bd8b7dc46 230 protected:
Khanchana 0:d98bd8b7dc46 231
Khanchana 0:d98bd8b7dc46 232 public:
Khanchana 0:d98bd8b7dc46 233 //===================================================================================================================
Khanchana 0:d98bd8b7dc46 234 //====== Set of useful function to access acceleratio, gyroscope, and temperature data
Khanchana 0:d98bd8b7dc46 235 //===================================================================================================================
Khanchana 0:d98bd8b7dc46 236
Khanchana 0:d98bd8b7dc46 237 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
Khanchana 0:d98bd8b7dc46 238 {
Khanchana 0:d98bd8b7dc46 239 char data_write[2];
Khanchana 0:d98bd8b7dc46 240 data_write[0] = subAddress;
Khanchana 0:d98bd8b7dc46 241 data_write[1] = data;
Khanchana 0:d98bd8b7dc46 242 i2c.write(address, data_write, 2, 0);
Khanchana 0:d98bd8b7dc46 243 }
Khanchana 0:d98bd8b7dc46 244
Khanchana 0:d98bd8b7dc46 245 char readByte(uint8_t address, uint8_t subAddress)
Khanchana 0:d98bd8b7dc46 246 {
Khanchana 0:d98bd8b7dc46 247 char data[1]; // `data` will store the register data
Khanchana 0:d98bd8b7dc46 248 char data_write[1];
Khanchana 0:d98bd8b7dc46 249 data_write[0] = subAddress;
Khanchana 0:d98bd8b7dc46 250 i2c.write(address, data_write, 1, 1); // no stop
Khanchana 0:d98bd8b7dc46 251 i2c.read(address, data, 1, 0);
Khanchana 0:d98bd8b7dc46 252 return data[0];
Khanchana 0:d98bd8b7dc46 253 }
Khanchana 0:d98bd8b7dc46 254
Khanchana 0:d98bd8b7dc46 255 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
Khanchana 0:d98bd8b7dc46 256 {
Khanchana 0:d98bd8b7dc46 257 char data[14];
Khanchana 0:d98bd8b7dc46 258 char data_write[1];
Khanchana 0:d98bd8b7dc46 259 data_write[0] = subAddress;
Khanchana 0:d98bd8b7dc46 260 i2c.write(address, data_write, 1, 1); // no stop
Khanchana 0:d98bd8b7dc46 261 i2c.read(address, data, count, 0);
Khanchana 0:d98bd8b7dc46 262 for(int ii = 0; ii < count; ii++) {
Khanchana 0:d98bd8b7dc46 263 dest[ii] = data[ii];
Khanchana 0:d98bd8b7dc46 264 }
Khanchana 0:d98bd8b7dc46 265 }
Khanchana 0:d98bd8b7dc46 266
Khanchana 0:d98bd8b7dc46 267
Khanchana 0:d98bd8b7dc46 268 void getMres() {
Khanchana 0:d98bd8b7dc46 269 switch (Mscale)
Khanchana 0:d98bd8b7dc46 270 {
Khanchana 0:d98bd8b7dc46 271 // Possible magnetometer scales (and their register bit settings) are:
Khanchana 0:d98bd8b7dc46 272 // 14 bit resolution (0) and 16 bit resolution (1)
Khanchana 0:d98bd8b7dc46 273 case MFS_14BITS:
Khanchana 0:d98bd8b7dc46 274 mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss
Khanchana 0:d98bd8b7dc46 275 break;
Khanchana 0:d98bd8b7dc46 276 case MFS_16BITS:
Khanchana 0:d98bd8b7dc46 277 mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss
Khanchana 0:d98bd8b7dc46 278 break;
Khanchana 0:d98bd8b7dc46 279 }
Khanchana 0:d98bd8b7dc46 280 }
Khanchana 0:d98bd8b7dc46 281
Khanchana 0:d98bd8b7dc46 282
Khanchana 0:d98bd8b7dc46 283 void getGres() {
Khanchana 0:d98bd8b7dc46 284 switch (Gscale)
Khanchana 0:d98bd8b7dc46 285 {
Khanchana 0:d98bd8b7dc46 286 // Possible gyro scales (and their register bit settings) are:
Khanchana 0:d98bd8b7dc46 287 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
Khanchana 0:d98bd8b7dc46 288 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
Khanchana 0:d98bd8b7dc46 289 case GFS_250DPS:
Khanchana 0:d98bd8b7dc46 290 gRes = 250.0/32768.0;
Khanchana 0:d98bd8b7dc46 291 break;
Khanchana 0:d98bd8b7dc46 292 case GFS_500DPS:
Khanchana 0:d98bd8b7dc46 293 gRes = 500.0/32768.0;
Khanchana 0:d98bd8b7dc46 294 break;
Khanchana 0:d98bd8b7dc46 295 case GFS_1000DPS:
Khanchana 0:d98bd8b7dc46 296 gRes = 1000.0/32768.0;
Khanchana 0:d98bd8b7dc46 297 break;
Khanchana 0:d98bd8b7dc46 298 case GFS_2000DPS:
Khanchana 0:d98bd8b7dc46 299 gRes = 2000.0/32768.0;
Khanchana 0:d98bd8b7dc46 300 break;
Khanchana 0:d98bd8b7dc46 301 }
Khanchana 0:d98bd8b7dc46 302 }
Khanchana 0:d98bd8b7dc46 303
Khanchana 0:d98bd8b7dc46 304
Khanchana 0:d98bd8b7dc46 305 void getAres() {
Khanchana 0:d98bd8b7dc46 306 switch (Ascale)
Khanchana 0:d98bd8b7dc46 307 {
Khanchana 0:d98bd8b7dc46 308 // Possible accelerometer scales (and their register bit settings) are:
Khanchana 0:d98bd8b7dc46 309 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
Khanchana 0:d98bd8b7dc46 310 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
Khanchana 0:d98bd8b7dc46 311 case AFS_2G:
Khanchana 0:d98bd8b7dc46 312 aRes = 2.0/32768.0;
Khanchana 0:d98bd8b7dc46 313 break;
Khanchana 0:d98bd8b7dc46 314 case AFS_4G:
Khanchana 0:d98bd8b7dc46 315 aRes = 4.0/32768.0;
Khanchana 0:d98bd8b7dc46 316 break;
Khanchana 0:d98bd8b7dc46 317 case AFS_8G:
Khanchana 0:d98bd8b7dc46 318 aRes = 8.0/32768.0;
Khanchana 0:d98bd8b7dc46 319 break;
Khanchana 0:d98bd8b7dc46 320 case AFS_16G:
Khanchana 0:d98bd8b7dc46 321 aRes = 16.0/32768.0;
Khanchana 0:d98bd8b7dc46 322 break;
Khanchana 0:d98bd8b7dc46 323 }
Khanchana 0:d98bd8b7dc46 324 }
Khanchana 0:d98bd8b7dc46 325
Khanchana 0:d98bd8b7dc46 326
Khanchana 0:d98bd8b7dc46 327 void readAccelData(int16_t * destination)
Khanchana 0:d98bd8b7dc46 328 {
Khanchana 0:d98bd8b7dc46 329 uint8_t rawData[6]; // x/y/z accel register data stored here
Khanchana 0:d98bd8b7dc46 330 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
Khanchana 0:d98bd8b7dc46 331 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
Khanchana 0:d98bd8b7dc46 332 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
Khanchana 0:d98bd8b7dc46 333 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
Khanchana 0:d98bd8b7dc46 334 }
Khanchana 0:d98bd8b7dc46 335
Khanchana 0:d98bd8b7dc46 336 void readGyroData(int16_t * destination)
Khanchana 0:d98bd8b7dc46 337 {
Khanchana 0:d98bd8b7dc46 338 uint8_t rawData[6]; // x/y/z gyro register data stored here
Khanchana 0:d98bd8b7dc46 339 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
Khanchana 0:d98bd8b7dc46 340 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
Khanchana 0:d98bd8b7dc46 341 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
Khanchana 0:d98bd8b7dc46 342 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
Khanchana 0:d98bd8b7dc46 343 }
Khanchana 0:d98bd8b7dc46 344
Khanchana 0:d98bd8b7dc46 345 void readMagData(int16_t * destination)
Khanchana 0:d98bd8b7dc46 346 {
Khanchana 0:d98bd8b7dc46 347 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
Khanchana 0:d98bd8b7dc46 348 if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set
Khanchana 0:d98bd8b7dc46 349 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
Khanchana 0:d98bd8b7dc46 350 uint8_t c = rawData[6]; // End data read by reading ST2 register
Khanchana 0:d98bd8b7dc46 351 if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data
Khanchana 0:d98bd8b7dc46 352 destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value
Khanchana 0:d98bd8b7dc46 353 destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian
Khanchana 0:d98bd8b7dc46 354 destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ;
Khanchana 0:d98bd8b7dc46 355 }
Khanchana 0:d98bd8b7dc46 356 }
Khanchana 0:d98bd8b7dc46 357 }
Khanchana 0:d98bd8b7dc46 358
Khanchana 0:d98bd8b7dc46 359 int16_t readTempData()
Khanchana 0:d98bd8b7dc46 360 {
Khanchana 0:d98bd8b7dc46 361 uint8_t rawData[2]; // x/y/z gyro register data stored here
Khanchana 0:d98bd8b7dc46 362 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
Khanchana 0:d98bd8b7dc46 363 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
Khanchana 0:d98bd8b7dc46 364 }
Khanchana 0:d98bd8b7dc46 365
Khanchana 0:d98bd8b7dc46 366
Khanchana 0:d98bd8b7dc46 367 void resetMPU9250() {
Khanchana 0:d98bd8b7dc46 368 // reset device
Khanchana 0:d98bd8b7dc46 369 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
Khanchana 0:d98bd8b7dc46 370 wait(0.1);
Khanchana 0:d98bd8b7dc46 371 }
Khanchana 0:d98bd8b7dc46 372
Khanchana 0:d98bd8b7dc46 373 void initAK8963(float * destination)
Khanchana 0:d98bd8b7dc46 374 {
Khanchana 0:d98bd8b7dc46 375 // First extract the factory calibration for each magnetometer axis
Khanchana 0:d98bd8b7dc46 376 uint8_t rawData[3]; // x/y/z gyro calibration data stored here
Khanchana 0:d98bd8b7dc46 377 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
Khanchana 0:d98bd8b7dc46 378 wait(0.01);
Khanchana 0:d98bd8b7dc46 379 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
Khanchana 0:d98bd8b7dc46 380 wait(0.01);
Khanchana 0:d98bd8b7dc46 381 readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
Khanchana 0:d98bd8b7dc46 382 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
Khanchana 0:d98bd8b7dc46 383 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
Khanchana 0:d98bd8b7dc46 384 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
Khanchana 0:d98bd8b7dc46 385 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
Khanchana 0:d98bd8b7dc46 386 wait(0.01);
Khanchana 0:d98bd8b7dc46 387 // Configure the magnetometer for continuous read and highest resolution
Khanchana 0:d98bd8b7dc46 388 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
Khanchana 0:d98bd8b7dc46 389 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
Khanchana 0:d98bd8b7dc46 390 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
Khanchana 0:d98bd8b7dc46 391 wait(0.01);
Khanchana 0:d98bd8b7dc46 392 }
Khanchana 0:d98bd8b7dc46 393
Khanchana 0:d98bd8b7dc46 394
Khanchana 0:d98bd8b7dc46 395 void initMPU9250()
Khanchana 0:d98bd8b7dc46 396 {
Khanchana 0:d98bd8b7dc46 397 // Initialize MPU9250 device
Khanchana 0:d98bd8b7dc46 398 // wake up device
Khanchana 0:d98bd8b7dc46 399 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
Khanchana 0:d98bd8b7dc46 400 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
Khanchana 0:d98bd8b7dc46 401
Khanchana 0:d98bd8b7dc46 402 // get stable time source
Khanchana 0:d98bd8b7dc46 403 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
Khanchana 0:d98bd8b7dc46 404
Khanchana 0:d98bd8b7dc46 405 // Configure Gyro and Accelerometer
Khanchana 0:d98bd8b7dc46 406 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
Khanchana 0:d98bd8b7dc46 407 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
Khanchana 0:d98bd8b7dc46 408 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
Khanchana 0:d98bd8b7dc46 409 writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
Khanchana 0:d98bd8b7dc46 410
Khanchana 0:d98bd8b7dc46 411 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
Khanchana 0:d98bd8b7dc46 412 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
Khanchana 0:d98bd8b7dc46 413
Khanchana 0:d98bd8b7dc46 414 // Set gyroscope full scale range
Khanchana 0:d98bd8b7dc46 415 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
Khanchana 0:d98bd8b7dc46 416 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
Khanchana 0:d98bd8b7dc46 417 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
Khanchana 0:d98bd8b7dc46 418 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
Khanchana 0:d98bd8b7dc46 419 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
Khanchana 0:d98bd8b7dc46 420
Khanchana 0:d98bd8b7dc46 421 // Set accelerometer configuration
Khanchana 0:d98bd8b7dc46 422 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
Khanchana 0:d98bd8b7dc46 423 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
Khanchana 0:d98bd8b7dc46 424 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
Khanchana 0:d98bd8b7dc46 425 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
Khanchana 0:d98bd8b7dc46 426
Khanchana 0:d98bd8b7dc46 427 // Set accelerometer sample rate configuration
Khanchana 0:d98bd8b7dc46 428 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
Khanchana 0:d98bd8b7dc46 429 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
Khanchana 0:d98bd8b7dc46 430 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
Khanchana 0:d98bd8b7dc46 431 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
Khanchana 0:d98bd8b7dc46 432 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
Khanchana 0:d98bd8b7dc46 433
Khanchana 0:d98bd8b7dc46 434 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
Khanchana 0:d98bd8b7dc46 435 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
Khanchana 0:d98bd8b7dc46 436
Khanchana 0:d98bd8b7dc46 437 // Configure Interrupts and Bypass Enable
Khanchana 0:d98bd8b7dc46 438 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
Khanchana 0:d98bd8b7dc46 439 // can join the I2C bus and all can be controlled by the Arduino as master
Khanchana 0:d98bd8b7dc46 440 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
Khanchana 0:d98bd8b7dc46 441 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
Khanchana 0:d98bd8b7dc46 442 }
Khanchana 0:d98bd8b7dc46 443
Khanchana 0:d98bd8b7dc46 444 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
Khanchana 0:d98bd8b7dc46 445 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
Khanchana 0:d98bd8b7dc46 446 void calibrateMPU9250(float * dest1, float * dest2)
Khanchana 0:d98bd8b7dc46 447 {
Khanchana 0:d98bd8b7dc46 448 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
Khanchana 0:d98bd8b7dc46 449 uint16_t ii, packet_count, fifo_count;
Khanchana 0:d98bd8b7dc46 450 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
Khanchana 0:d98bd8b7dc46 451
Khanchana 0:d98bd8b7dc46 452 // reset device, reset all registers, clear gyro and accelerometer bias registers
Khanchana 0:d98bd8b7dc46 453 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
Khanchana 0:d98bd8b7dc46 454 wait(0.1);
Khanchana 0:d98bd8b7dc46 455
Khanchana 0:d98bd8b7dc46 456 // get stable time source
Khanchana 0:d98bd8b7dc46 457 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
Khanchana 0:d98bd8b7dc46 458 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
Khanchana 0:d98bd8b7dc46 459 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
Khanchana 0:d98bd8b7dc46 460 wait(0.2);
Khanchana 0:d98bd8b7dc46 461
Khanchana 0:d98bd8b7dc46 462 // Configure device for bias calculation
Khanchana 0:d98bd8b7dc46 463 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
Khanchana 0:d98bd8b7dc46 464 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
Khanchana 0:d98bd8b7dc46 465 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
Khanchana 0:d98bd8b7dc46 466 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
Khanchana 0:d98bd8b7dc46 467 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
Khanchana 0:d98bd8b7dc46 468 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
Khanchana 0:d98bd8b7dc46 469 wait(0.015);
Khanchana 0:d98bd8b7dc46 470
Khanchana 0:d98bd8b7dc46 471 // Configure MPU9250 gyro and accelerometer for bias calculation
Khanchana 0:d98bd8b7dc46 472 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
Khanchana 0:d98bd8b7dc46 473 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
Khanchana 0:d98bd8b7dc46 474 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
Khanchana 0:d98bd8b7dc46 475 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
Khanchana 0:d98bd8b7dc46 476
Khanchana 0:d98bd8b7dc46 477 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
Khanchana 0:d98bd8b7dc46 478 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
Khanchana 0:d98bd8b7dc46 479
Khanchana 0:d98bd8b7dc46 480 // Configure FIFO to capture accelerometer and gyro data for bias calculation
Khanchana 0:d98bd8b7dc46 481 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
Khanchana 0:d98bd8b7dc46 482 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
Khanchana 0:d98bd8b7dc46 483 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
Khanchana 0:d98bd8b7dc46 484
Khanchana 0:d98bd8b7dc46 485 // At end of sample accumulation, turn off FIFO sensor read
Khanchana 0:d98bd8b7dc46 486 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
Khanchana 0:d98bd8b7dc46 487 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
Khanchana 0:d98bd8b7dc46 488 fifo_count = ((uint16_t)data[0] << 8) | data[1];
Khanchana 0:d98bd8b7dc46 489 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
Khanchana 0:d98bd8b7dc46 490
Khanchana 0:d98bd8b7dc46 491 for (ii = 0; ii < packet_count; ii++) {
Khanchana 0:d98bd8b7dc46 492 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
Khanchana 0:d98bd8b7dc46 493 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
Khanchana 0:d98bd8b7dc46 494 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
Khanchana 0:d98bd8b7dc46 495 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
Khanchana 0:d98bd8b7dc46 496 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
Khanchana 0:d98bd8b7dc46 497 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
Khanchana 0:d98bd8b7dc46 498 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
Khanchana 0:d98bd8b7dc46 499 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
Khanchana 0:d98bd8b7dc46 500
Khanchana 0:d98bd8b7dc46 501 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
Khanchana 0:d98bd8b7dc46 502 accel_bias[1] += (int32_t) accel_temp[1];
Khanchana 0:d98bd8b7dc46 503 accel_bias[2] += (int32_t) accel_temp[2];
Khanchana 0:d98bd8b7dc46 504 gyro_bias[0] += (int32_t) gyro_temp[0];
Khanchana 0:d98bd8b7dc46 505 gyro_bias[1] += (int32_t) gyro_temp[1];
Khanchana 0:d98bd8b7dc46 506 gyro_bias[2] += (int32_t) gyro_temp[2];
Khanchana 0:d98bd8b7dc46 507
Khanchana 0:d98bd8b7dc46 508 }
Khanchana 0:d98bd8b7dc46 509 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
Khanchana 0:d98bd8b7dc46 510 accel_bias[1] /= (int32_t) packet_count;
Khanchana 0:d98bd8b7dc46 511 accel_bias[2] /= (int32_t) packet_count;
Khanchana 0:d98bd8b7dc46 512 gyro_bias[0] /= (int32_t) packet_count;
Khanchana 0:d98bd8b7dc46 513 gyro_bias[1] /= (int32_t) packet_count;
Khanchana 0:d98bd8b7dc46 514 gyro_bias[2] /= (int32_t) packet_count;
Khanchana 0:d98bd8b7dc46 515
Khanchana 0:d98bd8b7dc46 516 if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation
Khanchana 0:d98bd8b7dc46 517 else {accel_bias[2] += (int32_t) accelsensitivity;}
Khanchana 0:d98bd8b7dc46 518
Khanchana 0:d98bd8b7dc46 519 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
Khanchana 0:d98bd8b7dc46 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
Khanchana 0:d98bd8b7dc46 521 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
Khanchana 0:d98bd8b7dc46 522 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
Khanchana 0:d98bd8b7dc46 523 data[3] = (-gyro_bias[1]/4) & 0xFF;
Khanchana 0:d98bd8b7dc46 524 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
Khanchana 0:d98bd8b7dc46 525 data[5] = (-gyro_bias[2]/4) & 0xFF;
Khanchana 0:d98bd8b7dc46 526
Khanchana 0:d98bd8b7dc46 527 /// Push gyro biases to hardware registers
Khanchana 0:d98bd8b7dc46 528 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
Khanchana 0:d98bd8b7dc46 529 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
Khanchana 0:d98bd8b7dc46 530 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
Khanchana 0:d98bd8b7dc46 531 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
Khanchana 0:d98bd8b7dc46 532 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
Khanchana 0:d98bd8b7dc46 533 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);
Khanchana 0:d98bd8b7dc46 534 */
Khanchana 0:d98bd8b7dc46 535 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
Khanchana 0:d98bd8b7dc46 536 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
Khanchana 0:d98bd8b7dc46 537 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
Khanchana 0:d98bd8b7dc46 538
Khanchana 0:d98bd8b7dc46 539 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
Khanchana 0:d98bd8b7dc46 540 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
Khanchana 0:d98bd8b7dc46 541 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
Khanchana 0:d98bd8b7dc46 542 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
Khanchana 0:d98bd8b7dc46 543 // the accelerometer biases calculated above must be divided by 8.
Khanchana 0:d98bd8b7dc46 544
Khanchana 0:d98bd8b7dc46 545 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
Khanchana 0:d98bd8b7dc46 546 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
Khanchana 0:d98bd8b7dc46 547 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
Khanchana 0:d98bd8b7dc46 548 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
Khanchana 0:d98bd8b7dc46 549 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
Khanchana 0:d98bd8b7dc46 550 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
Khanchana 0:d98bd8b7dc46 551 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
Khanchana 0:d98bd8b7dc46 552
Khanchana 0:d98bd8b7dc46 553 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
Khanchana 0:d98bd8b7dc46 554 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
Khanchana 0:d98bd8b7dc46 555
Khanchana 0:d98bd8b7dc46 556 for(ii = 0; ii < 3; ii++) {
Khanchana 0:d98bd8b7dc46 557 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
Khanchana 0:d98bd8b7dc46 558 }
Khanchana 0:d98bd8b7dc46 559
Khanchana 0:d98bd8b7dc46 560 // Construct total accelerometer bias, including calculated average accelerometer bias from above
Khanchana 0:d98bd8b7dc46 561 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
Khanchana 0:d98bd8b7dc46 562 accel_bias_reg[1] -= (accel_bias[1]/8);
Khanchana 0:d98bd8b7dc46 563 accel_bias_reg[2] -= (accel_bias[2]/8);
Khanchana 0:d98bd8b7dc46 564
Khanchana 0:d98bd8b7dc46 565 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
Khanchana 0:d98bd8b7dc46 566 data[1] = (accel_bias_reg[0]) & 0xFF;
Khanchana 0:d98bd8b7dc46 567 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
Khanchana 0:d98bd8b7dc46 568 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
Khanchana 0:d98bd8b7dc46 569 data[3] = (accel_bias_reg[1]) & 0xFF;
Khanchana 0:d98bd8b7dc46 570 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
Khanchana 0:d98bd8b7dc46 571 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
Khanchana 0:d98bd8b7dc46 572 data[5] = (accel_bias_reg[2]) & 0xFF;
Khanchana 0:d98bd8b7dc46 573 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
Khanchana 0:d98bd8b7dc46 574
Khanchana 0:d98bd8b7dc46 575 // Apparently this is not working for the acceleration biases in the MPU-9250
Khanchana 0:d98bd8b7dc46 576 // Are we handling the temperature correction bit properly?
Khanchana 0:d98bd8b7dc46 577 // Push accelerometer biases to hardware registers
Khanchana 0:d98bd8b7dc46 578 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
Khanchana 0:d98bd8b7dc46 579 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
Khanchana 0:d98bd8b7dc46 580 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
Khanchana 0:d98bd8b7dc46 581 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
Khanchana 0:d98bd8b7dc46 582 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
Khanchana 0:d98bd8b7dc46 583 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);
Khanchana 0:d98bd8b7dc46 584 */
Khanchana 0:d98bd8b7dc46 585 // Output scaled accelerometer biases for manual subtraction in the main program
Khanchana 0:d98bd8b7dc46 586 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity;
Khanchana 0:d98bd8b7dc46 587 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity;
Khanchana 0:d98bd8b7dc46 588 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
Khanchana 0:d98bd8b7dc46 589 }
Khanchana 0:d98bd8b7dc46 590
Khanchana 0:d98bd8b7dc46 591
Khanchana 0:d98bd8b7dc46 592 // Accelerometer and gyroscope self test; check calibration wrt factory settings
Khanchana 0:d98bd8b7dc46 593 void MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
Khanchana 0:d98bd8b7dc46 594 {
Khanchana 0:d98bd8b7dc46 595 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
Khanchana 0:d98bd8b7dc46 596 uint8_t selfTest[6];
Khanchana 0:d98bd8b7dc46 597 int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3];
Khanchana 0:d98bd8b7dc46 598 float factoryTrim[6];
Khanchana 0:d98bd8b7dc46 599 uint8_t FS = 0;
Khanchana 0:d98bd8b7dc46 600
Khanchana 0:d98bd8b7dc46 601 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
Khanchana 0:d98bd8b7dc46 602 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
Khanchana 0:d98bd8b7dc46 603 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
Khanchana 0:d98bd8b7dc46 604 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
Khanchana 0:d98bd8b7dc46 605 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
Khanchana 0:d98bd8b7dc46 606
Khanchana 0:d98bd8b7dc46 607 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
Khanchana 0:d98bd8b7dc46 608
Khanchana 0:d98bd8b7dc46 609 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
Khanchana 0:d98bd8b7dc46 610 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
Khanchana 0:d98bd8b7dc46 611 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
Khanchana 0:d98bd8b7dc46 612 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
Khanchana 0:d98bd8b7dc46 613
Khanchana 0:d98bd8b7dc46 614 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
Khanchana 0:d98bd8b7dc46 615 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
Khanchana 0:d98bd8b7dc46 616 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
Khanchana 0:d98bd8b7dc46 617 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
Khanchana 0:d98bd8b7dc46 618 }
Khanchana 0:d98bd8b7dc46 619
Khanchana 0:d98bd8b7dc46 620 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
Khanchana 0:d98bd8b7dc46 621 aAvg[ii] /= 200;
Khanchana 0:d98bd8b7dc46 622 gAvg[ii] /= 200;
Khanchana 0:d98bd8b7dc46 623 }
Khanchana 0:d98bd8b7dc46 624
Khanchana 0:d98bd8b7dc46 625 // Configure the accelerometer for self-test
Khanchana 0:d98bd8b7dc46 626 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
Khanchana 0:d98bd8b7dc46 627 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
Khanchana 0:d98bd8b7dc46 628 wait_ms(25); // Delay a while to let the device stabilize
Khanchana 0:d98bd8b7dc46 629
Khanchana 0:d98bd8b7dc46 630 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
Khanchana 0:d98bd8b7dc46 631
Khanchana 0:d98bd8b7dc46 632 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
Khanchana 0:d98bd8b7dc46 633 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
Khanchana 0:d98bd8b7dc46 634 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
Khanchana 0:d98bd8b7dc46 635 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
Khanchana 0:d98bd8b7dc46 636
Khanchana 0:d98bd8b7dc46 637 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
Khanchana 0:d98bd8b7dc46 638 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
Khanchana 0:d98bd8b7dc46 639 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
Khanchana 0:d98bd8b7dc46 640 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
Khanchana 0:d98bd8b7dc46 641 }
Khanchana 0:d98bd8b7dc46 642
Khanchana 0:d98bd8b7dc46 643 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
Khanchana 0:d98bd8b7dc46 644 aSTAvg[ii] /= 200;
Khanchana 0:d98bd8b7dc46 645 gSTAvg[ii] /= 200;
Khanchana 0:d98bd8b7dc46 646 }
Khanchana 0:d98bd8b7dc46 647
Khanchana 0:d98bd8b7dc46 648 // Configure the gyro and accelerometer for normal operation
Khanchana 0:d98bd8b7dc46 649 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
Khanchana 0:d98bd8b7dc46 650 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
Khanchana 0:d98bd8b7dc46 651 wait_ms(25); // Delay a while to let the device stabilize
Khanchana 0:d98bd8b7dc46 652
Khanchana 0:d98bd8b7dc46 653 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
Khanchana 0:d98bd8b7dc46 654 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
Khanchana 0:d98bd8b7dc46 655 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
Khanchana 0:d98bd8b7dc46 656 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
Khanchana 0:d98bd8b7dc46 657 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
Khanchana 0:d98bd8b7dc46 658 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
Khanchana 0:d98bd8b7dc46 659 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
Khanchana 0:d98bd8b7dc46 660
Khanchana 0:d98bd8b7dc46 661 // Retrieve factory self-test value from self-test code reads
Khanchana 0:d98bd8b7dc46 662 factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation
Khanchana 0:d98bd8b7dc46 663 factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation
Khanchana 0:d98bd8b7dc46 664 factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation
Khanchana 0:d98bd8b7dc46 665 factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation
Khanchana 0:d98bd8b7dc46 666 factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation
Khanchana 0:d98bd8b7dc46 667 factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation
Khanchana 0:d98bd8b7dc46 668
Khanchana 0:d98bd8b7dc46 669 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
Khanchana 0:d98bd8b7dc46 670 // To get percent, must multiply by 100
Khanchana 0:d98bd8b7dc46 671 for (int i = 0; i < 3; i++) {
Khanchana 0:d98bd8b7dc46 672 destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences
Khanchana 0:d98bd8b7dc46 673 destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences
Khanchana 0:d98bd8b7dc46 674 }
Khanchana 0:d98bd8b7dc46 675
Khanchana 0:d98bd8b7dc46 676 }
Khanchana 0:d98bd8b7dc46 677
Khanchana 0:d98bd8b7dc46 678
Khanchana 0:d98bd8b7dc46 679
Khanchana 0:d98bd8b7dc46 680 // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
Khanchana 0:d98bd8b7dc46 681 // (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
Khanchana 0:d98bd8b7dc46 682 // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute
Khanchana 0:d98bd8b7dc46 683 // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
Khanchana 0:d98bd8b7dc46 684 // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
Khanchana 0:d98bd8b7dc46 685 // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
Khanchana 0:d98bd8b7dc46 686 void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
Khanchana 0:d98bd8b7dc46 687 {
Khanchana 0:d98bd8b7dc46 688 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
Khanchana 0:d98bd8b7dc46 689 float norm;
Khanchana 0:d98bd8b7dc46 690 float hx, hy, _2bx, _2bz;
Khanchana 0:d98bd8b7dc46 691 float s1, s2, s3, s4;
Khanchana 0:d98bd8b7dc46 692 float qDot1, qDot2, qDot3, qDot4;
Khanchana 0:d98bd8b7dc46 693
Khanchana 0:d98bd8b7dc46 694 // Auxiliary variables to avoid repeated arithmetic
Khanchana 0:d98bd8b7dc46 695 float _2q1mx;
Khanchana 0:d98bd8b7dc46 696 float _2q1my;
Khanchana 0:d98bd8b7dc46 697 float _2q1mz;
Khanchana 0:d98bd8b7dc46 698 float _2q2mx;
Khanchana 0:d98bd8b7dc46 699 float _4bx;
Khanchana 0:d98bd8b7dc46 700 float _4bz;
Khanchana 0:d98bd8b7dc46 701 float _2q1 = 2.0f * q1;
Khanchana 0:d98bd8b7dc46 702 float _2q2 = 2.0f * q2;
Khanchana 0:d98bd8b7dc46 703 float _2q3 = 2.0f * q3;
Khanchana 0:d98bd8b7dc46 704 float _2q4 = 2.0f * q4;
Khanchana 0:d98bd8b7dc46 705 float _2q1q3 = 2.0f * q1 * q3;
Khanchana 0:d98bd8b7dc46 706 float _2q3q4 = 2.0f * q3 * q4;
Khanchana 0:d98bd8b7dc46 707 float q1q1 = q1 * q1;
Khanchana 0:d98bd8b7dc46 708 float q1q2 = q1 * q2;
Khanchana 0:d98bd8b7dc46 709 float q1q3 = q1 * q3;
Khanchana 0:d98bd8b7dc46 710 float q1q4 = q1 * q4;
Khanchana 0:d98bd8b7dc46 711 float q2q2 = q2 * q2;
Khanchana 0:d98bd8b7dc46 712 float q2q3 = q2 * q3;
Khanchana 0:d98bd8b7dc46 713 float q2q4 = q2 * q4;
Khanchana 0:d98bd8b7dc46 714 float q3q3 = q3 * q3;
Khanchana 0:d98bd8b7dc46 715 float q3q4 = q3 * q4;
Khanchana 0:d98bd8b7dc46 716 float q4q4 = q4 * q4;
Khanchana 0:d98bd8b7dc46 717
Khanchana 0:d98bd8b7dc46 718 // Normalise accelerometer measurement
Khanchana 0:d98bd8b7dc46 719 norm = sqrt(ax * ax + ay * ay + az * az);
Khanchana 0:d98bd8b7dc46 720 if (norm == 0.0f) return; // handle NaN
Khanchana 0:d98bd8b7dc46 721 norm = 1.0f/norm;
Khanchana 0:d98bd8b7dc46 722 ax *= norm;
Khanchana 0:d98bd8b7dc46 723 ay *= norm;
Khanchana 0:d98bd8b7dc46 724 az *= norm;
Khanchana 0:d98bd8b7dc46 725
Khanchana 0:d98bd8b7dc46 726 // Normalise magnetometer measurement
Khanchana 0:d98bd8b7dc46 727 norm = sqrt(mx * mx + my * my + mz * mz);
Khanchana 0:d98bd8b7dc46 728 if (norm == 0.0f) return; // handle NaN
Khanchana 0:d98bd8b7dc46 729 norm = 1.0f/norm;
Khanchana 0:d98bd8b7dc46 730 mx *= norm;
Khanchana 0:d98bd8b7dc46 731 my *= norm;
Khanchana 0:d98bd8b7dc46 732 mz *= norm;
Khanchana 0:d98bd8b7dc46 733
Khanchana 0:d98bd8b7dc46 734 // Reference direction of Earth's magnetic field
Khanchana 0:d98bd8b7dc46 735 _2q1mx = 2.0f * q1 * mx;
Khanchana 0:d98bd8b7dc46 736 _2q1my = 2.0f * q1 * my;
Khanchana 0:d98bd8b7dc46 737 _2q1mz = 2.0f * q1 * mz;
Khanchana 0:d98bd8b7dc46 738 _2q2mx = 2.0f * q2 * mx;
Khanchana 0:d98bd8b7dc46 739 hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4;
Khanchana 0:d98bd8b7dc46 740 hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4;
Khanchana 0:d98bd8b7dc46 741 _2bx = sqrt(hx * hx + hy * hy);
Khanchana 0:d98bd8b7dc46 742 _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4;
Khanchana 0:d98bd8b7dc46 743 _4bx = 2.0f * _2bx;
Khanchana 0:d98bd8b7dc46 744 _4bz = 2.0f * _2bz;
Khanchana 0:d98bd8b7dc46 745
Khanchana 0:d98bd8b7dc46 746 // Gradient decent algorithm corrective step
Khanchana 0:d98bd8b7dc46 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);
Khanchana 0:d98bd8b7dc46 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);
Khanchana 0:d98bd8b7dc46 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);
Khanchana 0:d98bd8b7dc46 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);
Khanchana 0:d98bd8b7dc46 751 norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude
Khanchana 0:d98bd8b7dc46 752 norm = 1.0f/norm;
Khanchana 0:d98bd8b7dc46 753 s1 *= norm;
Khanchana 0:d98bd8b7dc46 754 s2 *= norm;
Khanchana 0:d98bd8b7dc46 755 s3 *= norm;
Khanchana 0:d98bd8b7dc46 756 s4 *= norm;
Khanchana 0:d98bd8b7dc46 757
Khanchana 0:d98bd8b7dc46 758 // Compute rate of change of quaternion
Khanchana 0:d98bd8b7dc46 759 qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1;
Khanchana 0:d98bd8b7dc46 760 qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2;
Khanchana 0:d98bd8b7dc46 761 qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3;
Khanchana 0:d98bd8b7dc46 762 qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4;
Khanchana 0:d98bd8b7dc46 763
Khanchana 0:d98bd8b7dc46 764 // Integrate to yield quaternion
Khanchana 0:d98bd8b7dc46 765 q1 += qDot1 * deltat;
Khanchana 0:d98bd8b7dc46 766 q2 += qDot2 * deltat;
Khanchana 0:d98bd8b7dc46 767 q3 += qDot3 * deltat;
Khanchana 0:d98bd8b7dc46 768 q4 += qDot4 * deltat;
Khanchana 0:d98bd8b7dc46 769 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
Khanchana 0:d98bd8b7dc46 770 norm = 1.0f/norm;
Khanchana 0:d98bd8b7dc46 771 q[0] = q1 * norm;
Khanchana 0:d98bd8b7dc46 772 q[1] = q2 * norm;
Khanchana 0:d98bd8b7dc46 773 q[2] = q3 * norm;
Khanchana 0:d98bd8b7dc46 774 q[3] = q4 * norm;
Khanchana 0:d98bd8b7dc46 775
Khanchana 0:d98bd8b7dc46 776 }
Khanchana 0:d98bd8b7dc46 777
Khanchana 0:d98bd8b7dc46 778
Khanchana 0:d98bd8b7dc46 779
Khanchana 0:d98bd8b7dc46 780 // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and
Khanchana 0:d98bd8b7dc46 781 // measured ones.
Khanchana 0:d98bd8b7dc46 782 void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
Khanchana 0:d98bd8b7dc46 783 {
Khanchana 0:d98bd8b7dc46 784 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
Khanchana 0:d98bd8b7dc46 785 float norm;
Khanchana 0:d98bd8b7dc46 786 float hx, hy, bx, bz;
Khanchana 0:d98bd8b7dc46 787 float vx, vy, vz, wx, wy, wz;
Khanchana 0:d98bd8b7dc46 788 float ex, ey, ez;
Khanchana 0:d98bd8b7dc46 789 float pa, pb, pc;
Khanchana 0:d98bd8b7dc46 790
Khanchana 0:d98bd8b7dc46 791 // Auxiliary variables to avoid repeated arithmetic
Khanchana 0:d98bd8b7dc46 792 float q1q1 = q1 * q1;
Khanchana 0:d98bd8b7dc46 793 float q1q2 = q1 * q2;
Khanchana 0:d98bd8b7dc46 794 float q1q3 = q1 * q3;
Khanchana 0:d98bd8b7dc46 795 float q1q4 = q1 * q4;
Khanchana 0:d98bd8b7dc46 796 float q2q2 = q2 * q2;
Khanchana 0:d98bd8b7dc46 797 float q2q3 = q2 * q3;
Khanchana 0:d98bd8b7dc46 798 float q2q4 = q2 * q4;
Khanchana 0:d98bd8b7dc46 799 float q3q3 = q3 * q3;
Khanchana 0:d98bd8b7dc46 800 float q3q4 = q3 * q4;
Khanchana 0:d98bd8b7dc46 801 float q4q4 = q4 * q4;
Khanchana 0:d98bd8b7dc46 802
Khanchana 0:d98bd8b7dc46 803 // Normalise accelerometer measurement
Khanchana 0:d98bd8b7dc46 804 norm = sqrt(ax * ax + ay * ay + az * az);
Khanchana 0:d98bd8b7dc46 805 if (norm == 0.0f) return; // handle NaN
Khanchana 0:d98bd8b7dc46 806 norm = 1.0f / norm; // use reciprocal for division
Khanchana 0:d98bd8b7dc46 807 ax *= norm;
Khanchana 0:d98bd8b7dc46 808 ay *= norm;
Khanchana 0:d98bd8b7dc46 809 az *= norm;
Khanchana 0:d98bd8b7dc46 810
Khanchana 0:d98bd8b7dc46 811 // Normalise magnetometer measurement
Khanchana 0:d98bd8b7dc46 812 norm = sqrt(mx * mx + my * my + mz * mz);
Khanchana 0:d98bd8b7dc46 813 if (norm == 0.0f) return; // handle NaN
Khanchana 0:d98bd8b7dc46 814 norm = 1.0f / norm; // use reciprocal for division
Khanchana 0:d98bd8b7dc46 815 mx *= norm;
Khanchana 0:d98bd8b7dc46 816 my *= norm;
Khanchana 0:d98bd8b7dc46 817 mz *= norm;
Khanchana 0:d98bd8b7dc46 818
Khanchana 0:d98bd8b7dc46 819 // Reference direction of Earth's magnetic field
Khanchana 0:d98bd8b7dc46 820 hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3);
Khanchana 0:d98bd8b7dc46 821 hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2);
Khanchana 0:d98bd8b7dc46 822 bx = sqrt((hx * hx) + (hy * hy));
Khanchana 0:d98bd8b7dc46 823 bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3);
Khanchana 0:d98bd8b7dc46 824
Khanchana 0:d98bd8b7dc46 825 // Estimated direction of gravity and magnetic field
Khanchana 0:d98bd8b7dc46 826 vx = 2.0f * (q2q4 - q1q3);
Khanchana 0:d98bd8b7dc46 827 vy = 2.0f * (q1q2 + q3q4);
Khanchana 0:d98bd8b7dc46 828 vz = q1q1 - q2q2 - q3q3 + q4q4;
Khanchana 0:d98bd8b7dc46 829 wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3);
Khanchana 0:d98bd8b7dc46 830 wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4);
Khanchana 0:d98bd8b7dc46 831 wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3);
Khanchana 0:d98bd8b7dc46 832
Khanchana 0:d98bd8b7dc46 833 // Error is cross product between estimated direction and measured direction of gravity
Khanchana 0:d98bd8b7dc46 834 ex = (ay * vz - az * vy) + (my * wz - mz * wy);
Khanchana 0:d98bd8b7dc46 835 ey = (az * vx - ax * vz) + (mz * wx - mx * wz);
Khanchana 0:d98bd8b7dc46 836 ez = (ax * vy - ay * vx) + (mx * wy - my * wx);
Khanchana 0:d98bd8b7dc46 837 if (Ki > 0.0f)
Khanchana 0:d98bd8b7dc46 838 {
Khanchana 0:d98bd8b7dc46 839 eInt[0] += ex; // accumulate integral error
Khanchana 0:d98bd8b7dc46 840 eInt[1] += ey;
Khanchana 0:d98bd8b7dc46 841 eInt[2] += ez;
Khanchana 0:d98bd8b7dc46 842 }
Khanchana 0:d98bd8b7dc46 843 else
Khanchana 0:d98bd8b7dc46 844 {
Khanchana 0:d98bd8b7dc46 845 eInt[0] = 0.0f; // prevent integral wind up
Khanchana 0:d98bd8b7dc46 846 eInt[1] = 0.0f;
Khanchana 0:d98bd8b7dc46 847 eInt[2] = 0.0f;
Khanchana 0:d98bd8b7dc46 848 }
Khanchana 0:d98bd8b7dc46 849
Khanchana 0:d98bd8b7dc46 850 // Apply feedback terms
Khanchana 0:d98bd8b7dc46 851 gx = gx + Kp * ex + Ki * eInt[0];
Khanchana 0:d98bd8b7dc46 852 gy = gy + Kp * ey + Ki * eInt[1];
Khanchana 0:d98bd8b7dc46 853 gz = gz + Kp * ez + Ki * eInt[2];
Khanchana 0:d98bd8b7dc46 854
Khanchana 0:d98bd8b7dc46 855 // Integrate rate of change of quaternion
Khanchana 0:d98bd8b7dc46 856 pa = q2;
Khanchana 0:d98bd8b7dc46 857 pb = q3;
Khanchana 0:d98bd8b7dc46 858 pc = q4;
Khanchana 0:d98bd8b7dc46 859 q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat);
Khanchana 0:d98bd8b7dc46 860 q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat);
Khanchana 0:d98bd8b7dc46 861 q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat);
Khanchana 0:d98bd8b7dc46 862 q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat);
Khanchana 0:d98bd8b7dc46 863
Khanchana 0:d98bd8b7dc46 864 // Normalise quaternion
Khanchana 0:d98bd8b7dc46 865 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);
Khanchana 0:d98bd8b7dc46 866 norm = 1.0f / norm;
Khanchana 0:d98bd8b7dc46 867 q[0] = q1 * norm;
Khanchana 0:d98bd8b7dc46 868 q[1] = q2 * norm;
Khanchana 0:d98bd8b7dc46 869 q[2] = q3 * norm;
Khanchana 0:d98bd8b7dc46 870 q[3] = q4 * norm;
Khanchana 0:d98bd8b7dc46 871
Khanchana 0:d98bd8b7dc46 872 }
Khanchana 0:d98bd8b7dc46 873 };
Khanchana 0:d98bd8b7dc46 874 #endif