Kris Winer / MPU9250AHRS_nRF52832

Added mag calibration and interrupt-based data ready

Dependencies:   BLE_API mbed-src nRF51822

MPU9250.h@4:8d11bfc7cac0, 2016-09-22 (annotated)

Committer:
onehorse
Date:
Thu Sep 22 01:21:24 2016 +0000
Revision:
4:8d11bfc7cac0
Parent:
3:fe46f14f5aef 
Added mag calibration and interrupt-based data ready

Who changed what in which revision?

UserRevisionLine numberNew contents of line
onehorse 0:2e5e65a6fb30 1 #ifndef MPU9250_H
onehorse 0:2e5e65a6fb30 2 #define MPU9250_H
onehorse 0:2e5e65a6fb30 3
onehorse 0:2e5e65a6fb30 4 #include "mbed.h"
onehorse 0:2e5e65a6fb30 5 #include "math.h"
onehorse 0:2e5e65a6fb30 6
onehorse 0:2e5e65a6fb30 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
onehorse 0:2e5e65a6fb30 8 // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map
onehorse 0:2e5e65a6fb30 9 //
onehorse 0:2e5e65a6fb30 10 //Magnetometer Registers
onehorse 0:2e5e65a6fb30 11 #define AK8963_ADDRESS 0x0C<<1
onehorse 0:2e5e65a6fb30 12 #define WHO_AM_I_AK8963 0x00 // should return 0x48
onehorse 0:2e5e65a6fb30 13 #define INFO 0x01
onehorse 0:2e5e65a6fb30 14 #define AK8963_ST1 0x02 // data ready status bit 0
onehorse 0:2e5e65a6fb30 15 #define AK8963_XOUT_L 0x03 // data
onehorse 0:2e5e65a6fb30 16 #define AK8963_XOUT_H 0x04
onehorse 0:2e5e65a6fb30 17 #define AK8963_YOUT_L 0x05
onehorse 0:2e5e65a6fb30 18 #define AK8963_YOUT_H 0x06
onehorse 0:2e5e65a6fb30 19 #define AK8963_ZOUT_L 0x07
onehorse 0:2e5e65a6fb30 20 #define AK8963_ZOUT_H 0x08
onehorse 0:2e5e65a6fb30 21 #define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status bit 2
onehorse 0:2e5e65a6fb30 22 #define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001), self-test (1000) and Fuse ROM (1111) modes on bits 3:0
onehorse 0:2e5e65a6fb30 23 #define AK8963_ASTC 0x0C // Self test control
onehorse 0:2e5e65a6fb30 24 #define AK8963_I2CDIS 0x0F // I2C disable
onehorse 0:2e5e65a6fb30 25 #define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value
onehorse 0:2e5e65a6fb30 26 #define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value
onehorse 0:2e5e65a6fb30 27 #define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value
onehorse 0:2e5e65a6fb30 28
onehorse 0:2e5e65a6fb30 29 #define SELF_TEST_X_GYRO 0x00
onehorse 0:2e5e65a6fb30 30 #define SELF_TEST_Y_GYRO 0x01
onehorse 0:2e5e65a6fb30 31 #define SELF_TEST_Z_GYRO 0x02
onehorse 0:2e5e65a6fb30 32
onehorse 0:2e5e65a6fb30 33 /*#define X_FINE_GAIN 0x03 // [7:0] fine gain
onehorse 0:2e5e65a6fb30 34 #define Y_FINE_GAIN 0x04
onehorse 0:2e5e65a6fb30 35 #define Z_FINE_GAIN 0x05
onehorse 0:2e5e65a6fb30 36 #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer
onehorse 0:2e5e65a6fb30 37 #define XA_OFFSET_L_TC 0x07
onehorse 0:2e5e65a6fb30 38 #define YA_OFFSET_H 0x08
onehorse 0:2e5e65a6fb30 39 #define YA_OFFSET_L_TC 0x09
onehorse 0:2e5e65a6fb30 40 #define ZA_OFFSET_H 0x0A
onehorse 0:2e5e65a6fb30 41 #define ZA_OFFSET_L_TC 0x0B */
onehorse 0:2e5e65a6fb30 42
onehorse 0:2e5e65a6fb30 43 #define SELF_TEST_X_ACCEL 0x0D
onehorse 0:2e5e65a6fb30 44 #define SELF_TEST_Y_ACCEL 0x0E
onehorse 0:2e5e65a6fb30 45 #define SELF_TEST_Z_ACCEL 0x0F
onehorse 0:2e5e65a6fb30 46
onehorse 0:2e5e65a6fb30 47 #define SELF_TEST_A 0x10
onehorse 0:2e5e65a6fb30 48
onehorse 0:2e5e65a6fb30 49 #define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope
onehorse 0:2e5e65a6fb30 50 #define XG_OFFSET_L 0x14
onehorse 0:2e5e65a6fb30 51 #define YG_OFFSET_H 0x15
onehorse 0:2e5e65a6fb30 52 #define YG_OFFSET_L 0x16
onehorse 0:2e5e65a6fb30 53 #define ZG_OFFSET_H 0x17
onehorse 0:2e5e65a6fb30 54 #define ZG_OFFSET_L 0x18
onehorse 0:2e5e65a6fb30 55 #define SMPLRT_DIV 0x19
onehorse 0:2e5e65a6fb30 56 #define CONFIG 0x1A
onehorse 0:2e5e65a6fb30 57 #define GYRO_CONFIG 0x1B
onehorse 0:2e5e65a6fb30 58 #define ACCEL_CONFIG 0x1C
onehorse 0:2e5e65a6fb30 59 #define ACCEL_CONFIG2 0x1D
onehorse 0:2e5e65a6fb30 60 #define LP_ACCEL_ODR 0x1E
onehorse 0:2e5e65a6fb30 61 #define WOM_THR 0x1F
onehorse 0:2e5e65a6fb30 62
onehorse 0:2e5e65a6fb30 63 #define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms
onehorse 0:2e5e65a6fb30 64 #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]
onehorse 0:2e5e65a6fb30 65 #define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms
onehorse 0:2e5e65a6fb30 66
onehorse 0:2e5e65a6fb30 67 #define FIFO_EN 0x23
onehorse 0:2e5e65a6fb30 68 #define I2C_MST_CTRL 0x24
onehorse 0:2e5e65a6fb30 69 #define I2C_SLV0_ADDR 0x25
onehorse 0:2e5e65a6fb30 70 #define I2C_SLV0_REG 0x26
onehorse 0:2e5e65a6fb30 71 #define I2C_SLV0_CTRL 0x27
onehorse 0:2e5e65a6fb30 72 #define I2C_SLV1_ADDR 0x28
onehorse 0:2e5e65a6fb30 73 #define I2C_SLV1_REG 0x29
onehorse 0:2e5e65a6fb30 74 #define I2C_SLV1_CTRL 0x2A
onehorse 0:2e5e65a6fb30 75 #define I2C_SLV2_ADDR 0x2B
onehorse 0:2e5e65a6fb30 76 #define I2C_SLV2_REG 0x2C
onehorse 0:2e5e65a6fb30 77 #define I2C_SLV2_CTRL 0x2D
onehorse 0:2e5e65a6fb30 78 #define I2C_SLV3_ADDR 0x2E
onehorse 0:2e5e65a6fb30 79 #define I2C_SLV3_REG 0x2F
onehorse 0:2e5e65a6fb30 80 #define I2C_SLV3_CTRL 0x30
onehorse 0:2e5e65a6fb30 81 #define I2C_SLV4_ADDR 0x31
onehorse 0:2e5e65a6fb30 82 #define I2C_SLV4_REG 0x32
onehorse 0:2e5e65a6fb30 83 #define I2C_SLV4_DO 0x33
onehorse 0:2e5e65a6fb30 84 #define I2C_SLV4_CTRL 0x34
onehorse 0:2e5e65a6fb30 85 #define I2C_SLV4_DI 0x35
onehorse 0:2e5e65a6fb30 86 #define I2C_MST_STATUS 0x36
onehorse 0:2e5e65a6fb30 87 #define INT_PIN_CFG 0x37
onehorse 0:2e5e65a6fb30 88 #define INT_ENABLE 0x38
onehorse 0:2e5e65a6fb30 89 #define DMP_INT_STATUS 0x39 // Check DMP interrupt
onehorse 0:2e5e65a6fb30 90 #define INT_STATUS 0x3A
onehorse 0:2e5e65a6fb30 91 #define ACCEL_XOUT_H 0x3B
onehorse 0:2e5e65a6fb30 92 #define ACCEL_XOUT_L 0x3C
onehorse 0:2e5e65a6fb30 93 #define ACCEL_YOUT_H 0x3D
onehorse 0:2e5e65a6fb30 94 #define ACCEL_YOUT_L 0x3E
onehorse 0:2e5e65a6fb30 95 #define ACCEL_ZOUT_H 0x3F
onehorse 0:2e5e65a6fb30 96 #define ACCEL_ZOUT_L 0x40
onehorse 0:2e5e65a6fb30 97 #define TEMP_OUT_H 0x41
onehorse 0:2e5e65a6fb30 98 #define TEMP_OUT_L 0x42
onehorse 0:2e5e65a6fb30 99 #define GYRO_XOUT_H 0x43
onehorse 0:2e5e65a6fb30 100 #define GYRO_XOUT_L 0x44
onehorse 0:2e5e65a6fb30 101 #define GYRO_YOUT_H 0x45
onehorse 0:2e5e65a6fb30 102 #define GYRO_YOUT_L 0x46
onehorse 0:2e5e65a6fb30 103 #define GYRO_ZOUT_H 0x47
onehorse 0:2e5e65a6fb30 104 #define GYRO_ZOUT_L 0x48
onehorse 0:2e5e65a6fb30 105 #define EXT_SENS_DATA_00 0x49
onehorse 0:2e5e65a6fb30 106 #define EXT_SENS_DATA_01 0x4A
onehorse 0:2e5e65a6fb30 107 #define EXT_SENS_DATA_02 0x4B
onehorse 0:2e5e65a6fb30 108 #define EXT_SENS_DATA_03 0x4C
onehorse 0:2e5e65a6fb30 109 #define EXT_SENS_DATA_04 0x4D
onehorse 0:2e5e65a6fb30 110 #define EXT_SENS_DATA_05 0x4E
onehorse 0:2e5e65a6fb30 111 #define EXT_SENS_DATA_06 0x4F
onehorse 0:2e5e65a6fb30 112 #define EXT_SENS_DATA_07 0x50
onehorse 0:2e5e65a6fb30 113 #define EXT_SENS_DATA_08 0x51
onehorse 0:2e5e65a6fb30 114 #define EXT_SENS_DATA_09 0x52
onehorse 0:2e5e65a6fb30 115 #define EXT_SENS_DATA_10 0x53
onehorse 0:2e5e65a6fb30 116 #define EXT_SENS_DATA_11 0x54
onehorse 0:2e5e65a6fb30 117 #define EXT_SENS_DATA_12 0x55
onehorse 0:2e5e65a6fb30 118 #define EXT_SENS_DATA_13 0x56
onehorse 0:2e5e65a6fb30 119 #define EXT_SENS_DATA_14 0x57
onehorse 0:2e5e65a6fb30 120 #define EXT_SENS_DATA_15 0x58
onehorse 0:2e5e65a6fb30 121 #define EXT_SENS_DATA_16 0x59
onehorse 0:2e5e65a6fb30 122 #define EXT_SENS_DATA_17 0x5A
onehorse 0:2e5e65a6fb30 123 #define EXT_SENS_DATA_18 0x5B
onehorse 0:2e5e65a6fb30 124 #define EXT_SENS_DATA_19 0x5C
onehorse 0:2e5e65a6fb30 125 #define EXT_SENS_DATA_20 0x5D
onehorse 0:2e5e65a6fb30 126 #define EXT_SENS_DATA_21 0x5E
onehorse 0:2e5e65a6fb30 127 #define EXT_SENS_DATA_22 0x5F
onehorse 0:2e5e65a6fb30 128 #define EXT_SENS_DATA_23 0x60
onehorse 0:2e5e65a6fb30 129 #define MOT_DETECT_STATUS 0x61
onehorse 0:2e5e65a6fb30 130 #define I2C_SLV0_DO 0x63
onehorse 0:2e5e65a6fb30 131 #define I2C_SLV1_DO 0x64
onehorse 0:2e5e65a6fb30 132 #define I2C_SLV2_DO 0x65
onehorse 0:2e5e65a6fb30 133 #define I2C_SLV3_DO 0x66
onehorse 0:2e5e65a6fb30 134 #define I2C_MST_DELAY_CTRL 0x67
onehorse 0:2e5e65a6fb30 135 #define SIGNAL_PATH_RESET 0x68
onehorse 0:2e5e65a6fb30 136 #define MOT_DETECT_CTRL 0x69
onehorse 0:2e5e65a6fb30 137 #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP
onehorse 0:2e5e65a6fb30 138 #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode
onehorse 0:2e5e65a6fb30 139 #define PWR_MGMT_2 0x6C
onehorse 0:2e5e65a6fb30 140 #define DMP_BANK 0x6D // Activates a specific bank in the DMP
onehorse 0:2e5e65a6fb30 141 #define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank
onehorse 0:2e5e65a6fb30 142 #define DMP_REG 0x6F // Register in DMP from which to read or to which to write
onehorse 0:2e5e65a6fb30 143 #define DMP_REG_1 0x70
onehorse 0:2e5e65a6fb30 144 #define DMP_REG_2 0x71
onehorse 0:2e5e65a6fb30 145 #define FIFO_COUNTH 0x72
onehorse 0:2e5e65a6fb30 146 #define FIFO_COUNTL 0x73
onehorse 0:2e5e65a6fb30 147 #define FIFO_R_W 0x74
onehorse 0:2e5e65a6fb30 148 #define WHO_AM_I_MPU9250 0x75 // Should return 0x71
onehorse 0:2e5e65a6fb30 149 #define XA_OFFSET_H 0x77
onehorse 0:2e5e65a6fb30 150 #define XA_OFFSET_L 0x78
onehorse 0:2e5e65a6fb30 151 #define YA_OFFSET_H 0x7A
onehorse 0:2e5e65a6fb30 152 #define YA_OFFSET_L 0x7B
onehorse 0:2e5e65a6fb30 153 #define ZA_OFFSET_H 0x7D
onehorse 0:2e5e65a6fb30 154 #define ZA_OFFSET_L 0x7E
onehorse 0:2e5e65a6fb30 155
onehorse 0:2e5e65a6fb30 156 // Using the MSENSR-9250 breakout board, ADO is set to 0
onehorse 0:2e5e65a6fb30 157 // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1
onehorse 0:2e5e65a6fb30 158 //mbed uses the eight-bit device address, so shift seven-bit addresses left by one!
onehorse 0:2e5e65a6fb30 159 #define ADO 0
onehorse 0:2e5e65a6fb30 160 #if ADO
onehorse 0:2e5e65a6fb30 161 #define MPU9250_ADDRESS 0x69<<1 // Device address when ADO = 1
onehorse 0:2e5e65a6fb30 162 #else
onehorse 0:2e5e65a6fb30 163 #define MPU9250_ADDRESS 0x68<<1 // Device address when ADO = 0
onehorse 0:2e5e65a6fb30 164 #endif
onehorse 0:2e5e65a6fb30 165
onehorse 0:2e5e65a6fb30 166 // Set initial input parameters
onehorse 0:2e5e65a6fb30 167 enum Ascale {
onehorse 0:2e5e65a6fb30 168 AFS_2G = 0,
onehorse 0:2e5e65a6fb30 169 AFS_4G,
onehorse 0:2e5e65a6fb30 170 AFS_8G,
onehorse 0:2e5e65a6fb30 171 AFS_16G
onehorse 0:2e5e65a6fb30 172 };
onehorse 0:2e5e65a6fb30 173
onehorse 0:2e5e65a6fb30 174 enum Gscale {
onehorse 0:2e5e65a6fb30 175 GFS_250DPS = 0,
onehorse 0:2e5e65a6fb30 176 GFS_500DPS,
onehorse 0:2e5e65a6fb30 177 GFS_1000DPS,
onehorse 0:2e5e65a6fb30 178 GFS_2000DPS
onehorse 0:2e5e65a6fb30 179 };
onehorse 0:2e5e65a6fb30 180
onehorse 0:2e5e65a6fb30 181 enum Mscale {
onehorse 0:2e5e65a6fb30 182 MFS_14BITS = 0, // 0.6 mG per LSB
onehorse 0:2e5e65a6fb30 183 MFS_16BITS // 0.15 mG per LSB
onehorse 0:2e5e65a6fb30 184 };
onehorse 0:2e5e65a6fb30 185
onehorse 0:2e5e65a6fb30 186 uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G
onehorse 0:2e5e65a6fb30 187 uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS
onehorse 0:2e5e65a6fb30 188 uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution
onehorse 0:2e5e65a6fb30 189 uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR
onehorse 0:2e5e65a6fb30 190 float aRes, gRes, mRes; // scale resolutions per LSB for the sensors
onehorse 0:2e5e65a6fb30 191
onehorse 0:2e5e65a6fb30 192 //Set up I2C, (SDA,SCL)
onehorse 3:fe46f14f5aef 193 //I2C i2c(I2C_SDA, I2C_SCL);
onehorse 4:8d11bfc7cac0 194 //I2C i2c(P0_0, P0_1); // nRF51 FC
onehorse 4:8d11bfc7cac0 195 //I2C i2c(P0_6, P0_7); // nRF52 QFN dev board
onehorse 4:8d11bfc7cac0 196 I2C i2c(P0_6, P0_5); // nRF52 CIAA dev board
onehorse 0:2e5e65a6fb30 197
onehorse 4:8d11bfc7cac0 198 //DigitalOut myled(P0_19); // mbed kit
onehorse 4:8d11bfc7cac0 199 //DigitalOut myled(P0_18); // nRF51822 module
onehorse 4:8d11bfc7cac0 200 DigitalOut myled(P0_24); // nRF52832 module
onehorse 0:2e5e65a6fb30 201
onehorse 0:2e5e65a6fb30 202 // Pin definitions
onehorse 4:8d11bfc7cac0 203 bool newData = false;
onehorse 4:8d11bfc7cac0 204 bool newMagData = false;
onehorse 0:2e5e65a6fb30 205
onehorse 4:8d11bfc7cac0 206 int16_t MPU9250Data[7]; // used to read all 14 bytes at once from the MPU9250 accel/gyro
onehorse 0:2e5e65a6fb30 207 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
onehorse 0:2e5e65a6fb30 208 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
onehorse 0:2e5e65a6fb30 209 int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output
onehorse 0:2e5e65a6fb30 210 float magCalibration[3] = {0, 0, 0}, magbias[3] = {0, 0, 0}; // Factory mag calibration and mag bias
onehorse 4:8d11bfc7cac0 211 float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}, magBias[3] = {0, 0, 0}, magScale[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer
onehorse 0:2e5e65a6fb30 212 float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
onehorse 0:2e5e65a6fb30 213 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
onehorse 0:2e5e65a6fb30 214 float temperature;
onehorse 0:2e5e65a6fb30 215 float SelfTest[6];
onehorse 0:2e5e65a6fb30 216
onehorse 0:2e5e65a6fb30 217 int delt_t = 0; // used to control display output rate
onehorse 0:2e5e65a6fb30 218 int count = 0; // used to control display output rate
onehorse 0:2e5e65a6fb30 219
onehorse 0:2e5e65a6fb30 220 // parameters for 6 DoF sensor fusion calculations
onehorse 0:2e5e65a6fb30 221 float PI = 3.14159265358979323846f;
onehorse 0:2e5e65a6fb30 222 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
onehorse 0:2e5e65a6fb30 223 float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
onehorse 0:2e5e65a6fb30 224 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
onehorse 0:2e5e65a6fb30 225 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
onehorse 0:2e5e65a6fb30 226 #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
onehorse 0:2e5e65a6fb30 227 #define Ki 0.0f
onehorse 0:2e5e65a6fb30 228
onehorse 0:2e5e65a6fb30 229 float pitch, yaw, roll;
onehorse 0:2e5e65a6fb30 230 float deltat = 0.0f; // integration interval for both filter schemes
onehorse 0:2e5e65a6fb30 231 int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval
onehorse 0:2e5e65a6fb30 232 float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion
onehorse 0:2e5e65a6fb30 233 float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method
onehorse 0:2e5e65a6fb30 234
onehorse 0:2e5e65a6fb30 235 class MPU9250 {
onehorse 0:2e5e65a6fb30 236
onehorse 0:2e5e65a6fb30 237 protected:
onehorse 0:2e5e65a6fb30 238
onehorse 0:2e5e65a6fb30 239 public:
onehorse 0:2e5e65a6fb30 240 //===================================================================================================================
onehorse 0:2e5e65a6fb30 241 //====== Set of useful function to access acceleratio, gyroscope, and temperature data
onehorse 0:2e5e65a6fb30 242 //===================================================================================================================
onehorse 0:2e5e65a6fb30 243
onehorse 4:8d11bfc7cac0 244 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
onehorse 0:2e5e65a6fb30 245 {
onehorse 0:2e5e65a6fb30 246 char data_write[2];
onehorse 0:2e5e65a6fb30 247 data_write[0] = subAddress;
onehorse 0:2e5e65a6fb30 248 data_write[1] = data;
onehorse 0:2e5e65a6fb30 249 i2c.write(address, data_write, 2, 0);
onehorse 0:2e5e65a6fb30 250 }
onehorse 0:2e5e65a6fb30 251
onehorse 0:2e5e65a6fb30 252 char readByte(uint8_t address, uint8_t subAddress)
onehorse 0:2e5e65a6fb30 253 {
onehorse 0:2e5e65a6fb30 254 char data[1]; // `data` will store the register data
onehorse 0:2e5e65a6fb30 255 char data_write[1];
onehorse 0:2e5e65a6fb30 256 data_write[0] = subAddress;
onehorse 0:2e5e65a6fb30 257 i2c.write(address, data_write, 1, 1); // no stop
onehorse 0:2e5e65a6fb30 258 i2c.read(address, data, 1, 0);
onehorse 0:2e5e65a6fb30 259 return data[0];
onehorse 0:2e5e65a6fb30 260 }
onehorse 0:2e5e65a6fb30 261
onehorse 0:2e5e65a6fb30 262 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
onehorse 0:2e5e65a6fb30 263 {
onehorse 0:2e5e65a6fb30 264 char data[14];
onehorse 0:2e5e65a6fb30 265 char data_write[1];
onehorse 0:2e5e65a6fb30 266 data_write[0] = subAddress;
onehorse 0:2e5e65a6fb30 267 i2c.write(address, data_write, 1, 1); // no stop
onehorse 0:2e5e65a6fb30 268 i2c.read(address, data, count, 0);
onehorse 0:2e5e65a6fb30 269 for(int ii = 0; ii < count; ii++) {
onehorse 0:2e5e65a6fb30 270 dest[ii] = data[ii];
onehorse 0:2e5e65a6fb30 271 }
onehorse 0:2e5e65a6fb30 272 }
onehorse 0:2e5e65a6fb30 273
onehorse 0:2e5e65a6fb30 274
onehorse 0:2e5e65a6fb30 275 void getMres() {
onehorse 0:2e5e65a6fb30 276 switch (Mscale)
onehorse 0:2e5e65a6fb30 277 {
onehorse 0:2e5e65a6fb30 278 // Possible magnetometer scales (and their register bit settings) are:
onehorse 0:2e5e65a6fb30 279 // 14 bit resolution (0) and 16 bit resolution (1)
onehorse 0:2e5e65a6fb30 280 case MFS_14BITS:
onehorse 4:8d11bfc7cac0 281 mRes = 10.0*4912.0/8190.0; // Proper scale to return milliGauss
onehorse 0:2e5e65a6fb30 282 break;
onehorse 0:2e5e65a6fb30 283 case MFS_16BITS:
onehorse 4:8d11bfc7cac0 284 mRes = 10.0*4912.0/32760.0; // Proper scale to return milliGauss
onehorse 0:2e5e65a6fb30 285 break;
onehorse 0:2e5e65a6fb30 286 }
onehorse 0:2e5e65a6fb30 287 }
onehorse 0:2e5e65a6fb30 288
onehorse 0:2e5e65a6fb30 289
onehorse 0:2e5e65a6fb30 290 void getGres() {
onehorse 0:2e5e65a6fb30 291 switch (Gscale)
onehorse 0:2e5e65a6fb30 292 {
onehorse 0:2e5e65a6fb30 293 // Possible gyro scales (and their register bit settings) are:
onehorse 0:2e5e65a6fb30 294 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
onehorse 0:2e5e65a6fb30 295 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
onehorse 0:2e5e65a6fb30 296 case GFS_250DPS:
onehorse 4:8d11bfc7cac0 297 gRes = 250.0f/32768.0f;
onehorse 0:2e5e65a6fb30 298 break;
onehorse 0:2e5e65a6fb30 299 case GFS_500DPS:
onehorse 4:8d11bfc7cac0 300 gRes = 500.0f/32768.0f;
onehorse 0:2e5e65a6fb30 301 break;
onehorse 0:2e5e65a6fb30 302 case GFS_1000DPS:
onehorse 4:8d11bfc7cac0 303 gRes = 1000.0f/32768.0f;
onehorse 0:2e5e65a6fb30 304 break;
onehorse 0:2e5e65a6fb30 305 case GFS_2000DPS:
onehorse 4:8d11bfc7cac0 306 gRes = 2000.0f/32768.0f;
onehorse 0:2e5e65a6fb30 307 break;
onehorse 0:2e5e65a6fb30 308 }
onehorse 0:2e5e65a6fb30 309 }
onehorse 0:2e5e65a6fb30 310
onehorse 0:2e5e65a6fb30 311
onehorse 0:2e5e65a6fb30 312 void getAres() {
onehorse 0:2e5e65a6fb30 313 switch (Ascale)
onehorse 0:2e5e65a6fb30 314 {
onehorse 0:2e5e65a6fb30 315 // Possible accelerometer scales (and their register bit settings) are:
onehorse 0:2e5e65a6fb30 316 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
onehorse 0:2e5e65a6fb30 317 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
onehorse 0:2e5e65a6fb30 318 case AFS_2G:
onehorse 4:8d11bfc7cac0 319 aRes = 2.0f/32768.0f;
onehorse 0:2e5e65a6fb30 320 break;
onehorse 0:2e5e65a6fb30 321 case AFS_4G:
onehorse 4:8d11bfc7cac0 322 aRes = 4.0f/32768.0f;
onehorse 0:2e5e65a6fb30 323 break;
onehorse 0:2e5e65a6fb30 324 case AFS_8G:
onehorse 4:8d11bfc7cac0 325 aRes = 8.0f/32768.0f;
onehorse 0:2e5e65a6fb30 326 break;
onehorse 0:2e5e65a6fb30 327 case AFS_16G:
onehorse 4:8d11bfc7cac0 328 aRes = 16.0f/32768.0f;
onehorse 0:2e5e65a6fb30 329 break;
onehorse 0:2e5e65a6fb30 330 }
onehorse 0:2e5e65a6fb30 331 }
onehorse 0:2e5e65a6fb30 332
onehorse 4:8d11bfc7cac0 333 void readMPU9250Data(int16_t * destination)
onehorse 4:8d11bfc7cac0 334 {
onehorse 4:8d11bfc7cac0 335 uint8_t rawData[14]; // x/y/z accel register data stored here
onehorse 4:8d11bfc7cac0 336 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 14, &rawData[0]); // Read the 14 raw data registers into data array
onehorse 4:8d11bfc7cac0 337 destination[0] = ((int16_t)rawData[0] << 8) | rawData[1] ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 4:8d11bfc7cac0 338 destination[1] = ((int16_t)rawData[2] << 8) | rawData[3] ;
onehorse 4:8d11bfc7cac0 339 destination[2] = ((int16_t)rawData[4] << 8) | rawData[5] ;
onehorse 4:8d11bfc7cac0 340 destination[3] = ((int16_t)rawData[6] << 8) | rawData[7] ;
onehorse 4:8d11bfc7cac0 341 destination[4] = ((int16_t)rawData[8] << 8) | rawData[9] ;
onehorse 4:8d11bfc7cac0 342 destination[5] = ((int16_t)rawData[10] << 8) | rawData[11] ;
onehorse 4:8d11bfc7cac0 343 destination[6] = ((int16_t)rawData[12] << 8) | rawData[13] ;
onehorse 4:8d11bfc7cac0 344 }
onehorse 0:2e5e65a6fb30 345
onehorse 0:2e5e65a6fb30 346 void readAccelData(int16_t * destination)
onehorse 0:2e5e65a6fb30 347 {
onehorse 0:2e5e65a6fb30 348 uint8_t rawData[6]; // x/y/z accel register data stored here
onehorse 0:2e5e65a6fb30 349 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
onehorse 0:2e5e65a6fb30 350 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 0:2e5e65a6fb30 351 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
onehorse 0:2e5e65a6fb30 352 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
onehorse 0:2e5e65a6fb30 353 }
onehorse 0:2e5e65a6fb30 354
onehorse 0:2e5e65a6fb30 355 void readGyroData(int16_t * destination)
onehorse 0:2e5e65a6fb30 356 {
onehorse 0:2e5e65a6fb30 357 uint8_t rawData[6]; // x/y/z gyro register data stored here
onehorse 0:2e5e65a6fb30 358 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
onehorse 0:2e5e65a6fb30 359 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 0:2e5e65a6fb30 360 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
onehorse 0:2e5e65a6fb30 361 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
onehorse 0:2e5e65a6fb30 362 }
onehorse 0:2e5e65a6fb30 363
onehorse 0:2e5e65a6fb30 364 void readMagData(int16_t * destination)
onehorse 0:2e5e65a6fb30 365 {
onehorse 0:2e5e65a6fb30 366 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
onehorse 0:2e5e65a6fb30 367 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
onehorse 0:2e5e65a6fb30 368 uint8_t c = rawData[6]; // End data read by reading ST2 register
onehorse 0:2e5e65a6fb30 369 if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data
onehorse 4:8d11bfc7cac0 370 destination[0] = ((int16_t)rawData[1] << 8) | rawData[0] ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 4:8d11bfc7cac0 371 destination[1] = ((int16_t)rawData[3] << 8) | rawData[2] ; // Data stored as little Endian
onehorse 4:8d11bfc7cac0 372 destination[2] = ((int16_t)rawData[5] << 8) | rawData[4] ;
onehorse 0:2e5e65a6fb30 373 }
onehorse 0:2e5e65a6fb30 374 }
onehorse 0:2e5e65a6fb30 375
onehorse 0:2e5e65a6fb30 376 int16_t readTempData()
onehorse 0:2e5e65a6fb30 377 {
onehorse 0:2e5e65a6fb30 378 uint8_t rawData[2]; // x/y/z gyro register data stored here
onehorse 0:2e5e65a6fb30 379 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
onehorse 0:2e5e65a6fb30 380 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
onehorse 0:2e5e65a6fb30 381 }
onehorse 0:2e5e65a6fb30 382
onehorse 0:2e5e65a6fb30 383
onehorse 0:2e5e65a6fb30 384 void resetMPU9250() {
onehorse 0:2e5e65a6fb30 385 // reset device
onehorse 0:2e5e65a6fb30 386 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
onehorse 0:2e5e65a6fb30 387 wait(0.1);
onehorse 0:2e5e65a6fb30 388 }
onehorse 0:2e5e65a6fb30 389
onehorse 0:2e5e65a6fb30 390 void initAK8963(float * destination)
onehorse 0:2e5e65a6fb30 391 {
onehorse 0:2e5e65a6fb30 392 // First extract the factory calibration for each magnetometer axis
onehorse 4:8d11bfc7cac0 393 uint8_t rawData[3] = {0, 0, 0}; // x/y/z gyro calibration data stored here
onehorse 0:2e5e65a6fb30 394 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
onehorse 0:2e5e65a6fb30 395 wait(0.01);
onehorse 0:2e5e65a6fb30 396 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
onehorse 0:2e5e65a6fb30 397 wait(0.01);
onehorse 4:8d11bfc7cac0 398 // readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
onehorse 4:8d11bfc7cac0 399 rawData[0] = readByte(AK8963_ADDRESS, AK8963_ASAX);
onehorse 4:8d11bfc7cac0 400 rawData[1] = readByte(AK8963_ADDRESS, AK8963_ASAY);
onehorse 4:8d11bfc7cac0 401 rawData[2] = readByte(AK8963_ADDRESS, AK8963_ASAZ);
onehorse 0:2e5e65a6fb30 402 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
onehorse 0:2e5e65a6fb30 403 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
onehorse 0:2e5e65a6fb30 404 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
onehorse 0:2e5e65a6fb30 405 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
onehorse 0:2e5e65a6fb30 406 wait(0.01);
onehorse 0:2e5e65a6fb30 407 // Configure the magnetometer for continuous read and highest resolution
onehorse 0:2e5e65a6fb30 408 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
onehorse 0:2e5e65a6fb30 409 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
onehorse 0:2e5e65a6fb30 410 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
onehorse 0:2e5e65a6fb30 411 wait(0.01);
onehorse 0:2e5e65a6fb30 412 }
onehorse 0:2e5e65a6fb30 413
onehorse 0:2e5e65a6fb30 414
onehorse 0:2e5e65a6fb30 415 void initMPU9250()
onehorse 0:2e5e65a6fb30 416 {
onehorse 0:2e5e65a6fb30 417 // Initialize MPU9250 device
onehorse 0:2e5e65a6fb30 418 // wake up device
onehorse 0:2e5e65a6fb30 419 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
onehorse 0:2e5e65a6fb30 420 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
onehorse 0:2e5e65a6fb30 421
onehorse 0:2e5e65a6fb30 422 // get stable time source
onehorse 0:2e5e65a6fb30 423 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
onehorse 0:2e5e65a6fb30 424
onehorse 0:2e5e65a6fb30 425 // Configure Gyro and Accelerometer
onehorse 0:2e5e65a6fb30 426 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
onehorse 0:2e5e65a6fb30 427 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
onehorse 0:2e5e65a6fb30 428 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
onehorse 0:2e5e65a6fb30 429 writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
onehorse 0:2e5e65a6fb30 430
onehorse 0:2e5e65a6fb30 431 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
onehorse 0:2e5e65a6fb30 432 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
onehorse 0:2e5e65a6fb30 433
onehorse 0:2e5e65a6fb30 434 // Set gyroscope full scale range
onehorse 0:2e5e65a6fb30 435 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
onehorse 0:2e5e65a6fb30 436 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
onehorse 0:2e5e65a6fb30 437 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
onehorse 0:2e5e65a6fb30 438 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
onehorse 0:2e5e65a6fb30 439 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
onehorse 0:2e5e65a6fb30 440
onehorse 0:2e5e65a6fb30 441 // Set accelerometer configuration
onehorse 0:2e5e65a6fb30 442 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
onehorse 0:2e5e65a6fb30 443 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
onehorse 0:2e5e65a6fb30 444 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
onehorse 0:2e5e65a6fb30 445 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
onehorse 0:2e5e65a6fb30 446
onehorse 0:2e5e65a6fb30 447 // Set accelerometer sample rate configuration
onehorse 0:2e5e65a6fb30 448 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
onehorse 0:2e5e65a6fb30 449 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
onehorse 0:2e5e65a6fb30 450 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
onehorse 0:2e5e65a6fb30 451 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
onehorse 0:2e5e65a6fb30 452 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
onehorse 0:2e5e65a6fb30 453
onehorse 0:2e5e65a6fb30 454 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
onehorse 0:2e5e65a6fb30 455 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
onehorse 0:2e5e65a6fb30 456
onehorse 0:2e5e65a6fb30 457 // Configure Interrupts and Bypass Enable
onehorse 0:2e5e65a6fb30 458 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
onehorse 0:2e5e65a6fb30 459 // can join the I2C bus and all can be controlled by the Arduino as master
onehorse 4:8d11bfc7cac0 460 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x12); // INT is 50 microsecond pulse and any read to clear
onehorse 4:8d11bfc7cac0 461 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
onehorse 0:2e5e65a6fb30 462 }
onehorse 0:2e5e65a6fb30 463
onehorse 0:2e5e65a6fb30 464 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
onehorse 0:2e5e65a6fb30 465 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
onehorse 0:2e5e65a6fb30 466 void calibrateMPU9250(float * dest1, float * dest2)
onehorse 0:2e5e65a6fb30 467 {
onehorse 0:2e5e65a6fb30 468 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
onehorse 0:2e5e65a6fb30 469 uint16_t ii, packet_count, fifo_count;
onehorse 0:2e5e65a6fb30 470 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
onehorse 0:2e5e65a6fb30 471
onehorse 0:2e5e65a6fb30 472 // reset device, reset all registers, clear gyro and accelerometer bias registers
onehorse 0:2e5e65a6fb30 473 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
onehorse 0:2e5e65a6fb30 474 wait(0.1);
onehorse 0:2e5e65a6fb30 475
onehorse 0:2e5e65a6fb30 476 // get stable time source
onehorse 0:2e5e65a6fb30 477 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
onehorse 0:2e5e65a6fb30 478 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
onehorse 0:2e5e65a6fb30 479 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
onehorse 0:2e5e65a6fb30 480 wait(0.2);
onehorse 0:2e5e65a6fb30 481
onehorse 0:2e5e65a6fb30 482 // Configure device for bias calculation
onehorse 0:2e5e65a6fb30 483 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
onehorse 0:2e5e65a6fb30 484 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
onehorse 0:2e5e65a6fb30 485 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
onehorse 0:2e5e65a6fb30 486 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
onehorse 0:2e5e65a6fb30 487 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
onehorse 0:2e5e65a6fb30 488 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
onehorse 0:2e5e65a6fb30 489 wait(0.015);
onehorse 0:2e5e65a6fb30 490
onehorse 0:2e5e65a6fb30 491 // Configure MPU9250 gyro and accelerometer for bias calculation
onehorse 0:2e5e65a6fb30 492 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
onehorse 0:2e5e65a6fb30 493 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
onehorse 0:2e5e65a6fb30 494 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
onehorse 0:2e5e65a6fb30 495 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
onehorse 0:2e5e65a6fb30 496
onehorse 0:2e5e65a6fb30 497 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
onehorse 0:2e5e65a6fb30 498 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
onehorse 0:2e5e65a6fb30 499
onehorse 0:2e5e65a6fb30 500 // Configure FIFO to capture accelerometer and gyro data for bias calculation
onehorse 0:2e5e65a6fb30 501 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
onehorse 0:2e5e65a6fb30 502 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
onehorse 0:2e5e65a6fb30 503 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
onehorse 0:2e5e65a6fb30 504
onehorse 0:2e5e65a6fb30 505 // At end of sample accumulation, turn off FIFO sensor read
onehorse 0:2e5e65a6fb30 506 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
onehorse 0:2e5e65a6fb30 507 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
onehorse 0:2e5e65a6fb30 508 fifo_count = ((uint16_t)data[0] << 8) | data[1];
onehorse 0:2e5e65a6fb30 509 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
onehorse 0:2e5e65a6fb30 510
onehorse 0:2e5e65a6fb30 511 for (ii = 0; ii < packet_count; ii++) {
onehorse 0:2e5e65a6fb30 512 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
onehorse 0:2e5e65a6fb30 513 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
onehorse 0:2e5e65a6fb30 514 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
onehorse 0:2e5e65a6fb30 515 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
onehorse 0:2e5e65a6fb30 516 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
onehorse 0:2e5e65a6fb30 517 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
onehorse 0:2e5e65a6fb30 518 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
onehorse 0:2e5e65a6fb30 519 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
onehorse 0:2e5e65a6fb30 520
onehorse 0:2e5e65a6fb30 521 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
onehorse 0:2e5e65a6fb30 522 accel_bias[1] += (int32_t) accel_temp[1];
onehorse 0:2e5e65a6fb30 523 accel_bias[2] += (int32_t) accel_temp[2];
onehorse 0:2e5e65a6fb30 524 gyro_bias[0] += (int32_t) gyro_temp[0];
onehorse 0:2e5e65a6fb30 525 gyro_bias[1] += (int32_t) gyro_temp[1];
onehorse 0:2e5e65a6fb30 526 gyro_bias[2] += (int32_t) gyro_temp[2];
onehorse 0:2e5e65a6fb30 527
onehorse 0:2e5e65a6fb30 528 }
onehorse 0:2e5e65a6fb30 529 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
onehorse 0:2e5e65a6fb30 530 accel_bias[1] /= (int32_t) packet_count;
onehorse 0:2e5e65a6fb30 531 accel_bias[2] /= (int32_t) packet_count;
onehorse 0:2e5e65a6fb30 532 gyro_bias[0] /= (int32_t) packet_count;
onehorse 0:2e5e65a6fb30 533 gyro_bias[1] /= (int32_t) packet_count;
onehorse 0:2e5e65a6fb30 534 gyro_bias[2] /= (int32_t) packet_count;
onehorse 0:2e5e65a6fb30 535
onehorse 0:2e5e65a6fb30 536 if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation
onehorse 0:2e5e65a6fb30 537 else {accel_bias[2] += (int32_t) accelsensitivity;}
onehorse 0:2e5e65a6fb30 538
onehorse 0:2e5e65a6fb30 539 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
onehorse 0:2e5e65a6fb30 540 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
onehorse 0:2e5e65a6fb30 541 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
onehorse 0:2e5e65a6fb30 542 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
onehorse 0:2e5e65a6fb30 543 data[3] = (-gyro_bias[1]/4) & 0xFF;
onehorse 0:2e5e65a6fb30 544 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
onehorse 0:2e5e65a6fb30 545 data[5] = (-gyro_bias[2]/4) & 0xFF;
onehorse 0:2e5e65a6fb30 546
onehorse 0:2e5e65a6fb30 547 /// Push gyro biases to hardware registers
onehorse 0:2e5e65a6fb30 548 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
onehorse 0:2e5e65a6fb30 549 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
onehorse 0:2e5e65a6fb30 550 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
onehorse 0:2e5e65a6fb30 551 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
onehorse 0:2e5e65a6fb30 552 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
onehorse 0:2e5e65a6fb30 553 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);
onehorse 0:2e5e65a6fb30 554 */
onehorse 0:2e5e65a6fb30 555 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
onehorse 0:2e5e65a6fb30 556 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
onehorse 0:2e5e65a6fb30 557 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
onehorse 0:2e5e65a6fb30 558
onehorse 0:2e5e65a6fb30 559 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
onehorse 0:2e5e65a6fb30 560 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
onehorse 0:2e5e65a6fb30 561 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
onehorse 0:2e5e65a6fb30 562 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
onehorse 0:2e5e65a6fb30 563 // the accelerometer biases calculated above must be divided by 8.
onehorse 0:2e5e65a6fb30 564
onehorse 0:2e5e65a6fb30 565 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
onehorse 0:2e5e65a6fb30 566 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
onehorse 0:2e5e65a6fb30 567 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
onehorse 0:2e5e65a6fb30 568 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
onehorse 0:2e5e65a6fb30 569 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
onehorse 0:2e5e65a6fb30 570 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
onehorse 0:2e5e65a6fb30 571 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
onehorse 0:2e5e65a6fb30 572
onehorse 0:2e5e65a6fb30 573 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
onehorse 0:2e5e65a6fb30 574 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
onehorse 0:2e5e65a6fb30 575
onehorse 0:2e5e65a6fb30 576 for(ii = 0; ii < 3; ii++) {
onehorse 0:2e5e65a6fb30 577 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
onehorse 0:2e5e65a6fb30 578 }
onehorse 0:2e5e65a6fb30 579
onehorse 0:2e5e65a6fb30 580 // Construct total accelerometer bias, including calculated average accelerometer bias from above
onehorse 0:2e5e65a6fb30 581 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
onehorse 0:2e5e65a6fb30 582 accel_bias_reg[1] -= (accel_bias[1]/8);
onehorse 0:2e5e65a6fb30 583 accel_bias_reg[2] -= (accel_bias[2]/8);
onehorse 0:2e5e65a6fb30 584
onehorse 0:2e5e65a6fb30 585 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
onehorse 0:2e5e65a6fb30 586 data[1] = (accel_bias_reg[0]) & 0xFF;
onehorse 0:2e5e65a6fb30 587 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
onehorse 0:2e5e65a6fb30 588 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
onehorse 0:2e5e65a6fb30 589 data[3] = (accel_bias_reg[1]) & 0xFF;
onehorse 0:2e5e65a6fb30 590 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
onehorse 0:2e5e65a6fb30 591 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
onehorse 0:2e5e65a6fb30 592 data[5] = (accel_bias_reg[2]) & 0xFF;
onehorse 0:2e5e65a6fb30 593 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
onehorse 0:2e5e65a6fb30 594
onehorse 0:2e5e65a6fb30 595 // Apparently this is not working for the acceleration biases in the MPU-9250
onehorse 0:2e5e65a6fb30 596 // Are we handling the temperature correction bit properly?
onehorse 0:2e5e65a6fb30 597 // Push accelerometer biases to hardware registers
onehorse 0:2e5e65a6fb30 598 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
onehorse 0:2e5e65a6fb30 599 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
onehorse 0:2e5e65a6fb30 600 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
onehorse 0:2e5e65a6fb30 601 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
onehorse 0:2e5e65a6fb30 602 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
onehorse 0:2e5e65a6fb30 603 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);
onehorse 0:2e5e65a6fb30 604 */
onehorse 0:2e5e65a6fb30 605 // Output scaled accelerometer biases for manual subtraction in the main program
onehorse 0:2e5e65a6fb30 606 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity;
onehorse 0:2e5e65a6fb30 607 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity;
onehorse 0:2e5e65a6fb30 608 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
onehorse 0:2e5e65a6fb30 609 }
onehorse 0:2e5e65a6fb30 610
onehorse 4:8d11bfc7cac0 611 void magcalMPU9250(float * dest1, float * dest2)
onehorse 4:8d11bfc7cac0 612 {
onehorse 4:8d11bfc7cac0 613 uint16_t ii = 0, sample_count = 0;
onehorse 4:8d11bfc7cac0 614 int32_t mag_bias[3] = {0, 0, 0}, mag_scale[3] = {0, 0, 0};
onehorse 4:8d11bfc7cac0 615 int16_t mag_max[3] = {-32767, -32767, -32767}, mag_min[3] = {32767, 32767, 32767}, mag_temp[3] = {0, 0, 0};
onehorse 4:8d11bfc7cac0 616
onehorse 4:8d11bfc7cac0 617 // shoot for ~fifteen seconds of mag data
onehorse 4:8d11bfc7cac0 618 if(Mmode == 0x02) sample_count = 128; // at 8 Hz ODR, new mag data is available every 125 ms
onehorse 4:8d11bfc7cac0 619 if(Mmode == 0x06) sample_count = 1500; // at 100 Hz ODR, new mag data is available every 10 ms
onehorse 4:8d11bfc7cac0 620
onehorse 4:8d11bfc7cac0 621 for(ii = 0; ii < sample_count; ii++) {
onehorse 4:8d11bfc7cac0 622 readMagData(mag_temp); // Read the mag data
onehorse 4:8d11bfc7cac0 623
onehorse 4:8d11bfc7cac0 624 for (int jj = 0; jj < 3; jj++) {
onehorse 4:8d11bfc7cac0 625 if(mag_temp[jj] > mag_max[jj]) mag_max[jj] = mag_temp[jj];
onehorse 4:8d11bfc7cac0 626 if(mag_temp[jj] < mag_min[jj]) mag_min[jj] = mag_temp[jj];
onehorse 4:8d11bfc7cac0 627 }
onehorse 4:8d11bfc7cac0 628
onehorse 4:8d11bfc7cac0 629 if(Mmode == 0x02) wait(0.135); // at 8 Hz ODR, new mag data is available every 125 ms
onehorse 4:8d11bfc7cac0 630 if(Mmode == 0x06) wait(0.012); // at 100 Hz ODR, new mag data is available every 10 ms
onehorse 4:8d11bfc7cac0 631 }
onehorse 4:8d11bfc7cac0 632
onehorse 4:8d11bfc7cac0 633 // Get hard iron correction
onehorse 4:8d11bfc7cac0 634 mag_bias[0] = (mag_max[0] + mag_min[0])/2; // get average x mag bias in counts
onehorse 4:8d11bfc7cac0 635 mag_bias[1] = (mag_max[1] + mag_min[1])/2; // get average y mag bias in counts
onehorse 4:8d11bfc7cac0 636 mag_bias[2] = (mag_max[2] + mag_min[2])/2; // get average z mag bias in counts
onehorse 4:8d11bfc7cac0 637
onehorse 4:8d11bfc7cac0 638 dest1[0] = (float) mag_bias[0]*mRes*magCalibration[0]; // save mag biases in G for main program
onehorse 4:8d11bfc7cac0 639 dest1[1] = (float) mag_bias[1]*mRes*magCalibration[1];
onehorse 4:8d11bfc7cac0 640 dest1[2] = (float) mag_bias[2]*mRes*magCalibration[2];
onehorse 4:8d11bfc7cac0 641
onehorse 4:8d11bfc7cac0 642 // Get soft iron correction estimate
onehorse 4:8d11bfc7cac0 643 mag_scale[0] = (mag_max[0] - mag_min[0])/2; // get average x axis max chord length in counts
onehorse 4:8d11bfc7cac0 644 mag_scale[1] = (mag_max[1] - mag_min[1])/2; // get average y axis max chord length in counts
onehorse 4:8d11bfc7cac0 645 mag_scale[2] = (mag_max[2] - mag_min[2])/2; // get average z axis max chord length in counts
onehorse 4:8d11bfc7cac0 646
onehorse 4:8d11bfc7cac0 647 float avg_rad = mag_scale[0] + mag_scale[1] + mag_scale[2];
onehorse 4:8d11bfc7cac0 648 avg_rad /= 3.0;
onehorse 4:8d11bfc7cac0 649
onehorse 4:8d11bfc7cac0 650 dest2[0] = avg_rad/((float)mag_scale[0]);
onehorse 4:8d11bfc7cac0 651 dest2[1] = avg_rad/((float)mag_scale[1]);
onehorse 4:8d11bfc7cac0 652 dest2[2] = avg_rad/((float)mag_scale[2]);
onehorse 4:8d11bfc7cac0 653 }
onehorse 4:8d11bfc7cac0 654
onehorse 0:2e5e65a6fb30 655
onehorse 0:2e5e65a6fb30 656 // Accelerometer and gyroscope self test; check calibration wrt factory settings
onehorse 0:2e5e65a6fb30 657 void MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
onehorse 0:2e5e65a6fb30 658 {
onehorse 2:4e59a37182df 659 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
onehorse 0:2e5e65a6fb30 660 uint8_t selfTest[6];
onehorse 4:8d11bfc7cac0 661 int32_t gAvg[3] = {0, 0, 0}, aAvg[3] = {0, 0, 0}, aSTAvg[3] = {0, 0, 0}, gSTAvg[3] = {0, 0, 0};
onehorse 0:2e5e65a6fb30 662 float factoryTrim[6];
onehorse 2:4e59a37182df 663 uint8_t FS = 0;
onehorse 0:2e5e65a6fb30 664
onehorse 2:4e59a37182df 665 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
onehorse 2:4e59a37182df 666 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
onehorse 2:4e59a37182df 667 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
onehorse 2:4e59a37182df 668 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
onehorse 2:4e59a37182df 669 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
onehorse 2:4e59a37182df 670
onehorse 2:4e59a37182df 671 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
onehorse 2:4e59a37182df 672
onehorse 2:4e59a37182df 673 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
onehorse 2:4e59a37182df 674 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 2:4e59a37182df 675 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
onehorse 2:4e59a37182df 676 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
onehorse 2:4e59a37182df 677
onehorse 2:4e59a37182df 678 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
onehorse 2:4e59a37182df 679 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 2:4e59a37182df 680 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
onehorse 2:4e59a37182df 681 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
onehorse 2:4e59a37182df 682 }
onehorse 2:4e59a37182df 683
onehorse 2:4e59a37182df 684 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
onehorse 2:4e59a37182df 685 aAvg[ii] /= 200;
onehorse 2:4e59a37182df 686 gAvg[ii] /= 200;
onehorse 2:4e59a37182df 687 }
onehorse 2:4e59a37182df 688
onehorse 2:4e59a37182df 689 // Configure the accelerometer for self-test
onehorse 2:4e59a37182df 690 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
onehorse 2:4e59a37182df 691 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
onehorse 3:fe46f14f5aef 692 wait(0.025); // Delay a while to let the device stabilize
onehorse 2:4e59a37182df 693
onehorse 2:4e59a37182df 694 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
onehorse 2:4e59a37182df 695
onehorse 2:4e59a37182df 696 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
onehorse 2:4e59a37182df 697 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 2:4e59a37182df 698 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
onehorse 2:4e59a37182df 699 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
onehorse 2:4e59a37182df 700
onehorse 2:4e59a37182df 701 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
onehorse 2:4e59a37182df 702 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
onehorse 2:4e59a37182df 703 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
onehorse 2:4e59a37182df 704 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
onehorse 2:4e59a37182df 705 }
onehorse 2:4e59a37182df 706
onehorse 2:4e59a37182df 707 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
onehorse 2:4e59a37182df 708 aSTAvg[ii] /= 200;
onehorse 2:4e59a37182df 709 gSTAvg[ii] /= 200;
onehorse 2:4e59a37182df 710 }
onehorse 2:4e59a37182df 711
onehorse 2:4e59a37182df 712 // Configure the gyro and accelerometer for normal operation
onehorse 2:4e59a37182df 713 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
onehorse 2:4e59a37182df 714 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
onehorse 3:fe46f14f5aef 715 wait(0.025); // Delay a while to let the device stabilize
onehorse 0:2e5e65a6fb30 716
onehorse 2:4e59a37182df 717 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
onehorse 2:4e59a37182df 718 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
onehorse 2:4e59a37182df 719 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
onehorse 2:4e59a37182df 720 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
onehorse 2:4e59a37182df 721 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
onehorse 2:4e59a37182df 722 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
onehorse 2:4e59a37182df 723 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
onehorse 0:2e5e65a6fb30 724
onehorse 2:4e59a37182df 725 // Retrieve factory self-test value from self-test code reads
onehorse 2:4e59a37182df 726 factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation
onehorse 2:4e59a37182df 727 factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation
onehorse 2:4e59a37182df 728 factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation
onehorse 2:4e59a37182df 729 factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation
onehorse 2:4e59a37182df 730 factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation
onehorse 2:4e59a37182df 731 factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation
onehorse 2:4e59a37182df 732
onehorse 0:2e5e65a6fb30 733 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
onehorse 2:4e59a37182df 734 // To get percent, must multiply by 100
onehorse 2:4e59a37182df 735 for (int i = 0; i < 3; i++) {
onehorse 4:8d11bfc7cac0 736 destination[i] = 100.0f*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i] - 100.0f; // Report percent differences
onehorse 4:8d11bfc7cac0 737 destination[i+3] = 100.0f*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3] - 100.0f; // Report percent differences
onehorse 0:2e5e65a6fb30 738 }
onehorse 0:2e5e65a6fb30 739
onehorse 0:2e5e65a6fb30 740 }
onehorse 0:2e5e65a6fb30 741
onehorse 0:2e5e65a6fb30 742
onehorse 0:2e5e65a6fb30 743
onehorse 0:2e5e65a6fb30 744 // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
onehorse 0:2e5e65a6fb30 745 // (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
onehorse 0:2e5e65a6fb30 746 // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute
onehorse 0:2e5e65a6fb30 747 // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
onehorse 0:2e5e65a6fb30 748 // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
onehorse 0:2e5e65a6fb30 749 // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
onehorse 0:2e5e65a6fb30 750 void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
onehorse 0:2e5e65a6fb30 751 {
onehorse 0:2e5e65a6fb30 752 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
onehorse 0:2e5e65a6fb30 753 float norm;
onehorse 0:2e5e65a6fb30 754 float hx, hy, _2bx, _2bz;
onehorse 0:2e5e65a6fb30 755 float s1, s2, s3, s4;
onehorse 0:2e5e65a6fb30 756 float qDot1, qDot2, qDot3, qDot4;
onehorse 0:2e5e65a6fb30 757
onehorse 0:2e5e65a6fb30 758 // Auxiliary variables to avoid repeated arithmetic
onehorse 0:2e5e65a6fb30 759 float _2q1mx;
onehorse 0:2e5e65a6fb30 760 float _2q1my;
onehorse 0:2e5e65a6fb30 761 float _2q1mz;
onehorse 0:2e5e65a6fb30 762 float _2q2mx;
onehorse 0:2e5e65a6fb30 763 float _4bx;
onehorse 0:2e5e65a6fb30 764 float _4bz;
onehorse 0:2e5e65a6fb30 765 float _2q1 = 2.0f * q1;
onehorse 0:2e5e65a6fb30 766 float _2q2 = 2.0f * q2;
onehorse 0:2e5e65a6fb30 767 float _2q3 = 2.0f * q3;
onehorse 0:2e5e65a6fb30 768 float _2q4 = 2.0f * q4;
onehorse 0:2e5e65a6fb30 769 float _2q1q3 = 2.0f * q1 * q3;
onehorse 0:2e5e65a6fb30 770 float _2q3q4 = 2.0f * q3 * q4;
onehorse 0:2e5e65a6fb30 771 float q1q1 = q1 * q1;
onehorse 0:2e5e65a6fb30 772 float q1q2 = q1 * q2;
onehorse 0:2e5e65a6fb30 773 float q1q3 = q1 * q3;
onehorse 0:2e5e65a6fb30 774 float q1q4 = q1 * q4;
onehorse 0:2e5e65a6fb30 775 float q2q2 = q2 * q2;
onehorse 0:2e5e65a6fb30 776 float q2q3 = q2 * q3;
onehorse 0:2e5e65a6fb30 777 float q2q4 = q2 * q4;
onehorse 0:2e5e65a6fb30 778 float q3q3 = q3 * q3;
onehorse 0:2e5e65a6fb30 779 float q3q4 = q3 * q4;
onehorse 0:2e5e65a6fb30 780 float q4q4 = q4 * q4;
onehorse 0:2e5e65a6fb30 781
onehorse 0:2e5e65a6fb30 782 // Normalise accelerometer measurement
onehorse 4:8d11bfc7cac0 783 norm = sqrtf(ax * ax + ay * ay + az * az);
onehorse 0:2e5e65a6fb30 784 if (norm == 0.0f) return; // handle NaN
onehorse 0:2e5e65a6fb30 785 norm = 1.0f/norm;
onehorse 0:2e5e65a6fb30 786 ax *= norm;
onehorse 0:2e5e65a6fb30 787 ay *= norm;
onehorse 0:2e5e65a6fb30 788 az *= norm;
onehorse 0:2e5e65a6fb30 789
onehorse 0:2e5e65a6fb30 790 // Normalise magnetometer measurement
onehorse 4:8d11bfc7cac0 791 norm = sqrtf(mx * mx + my * my + mz * mz);
onehorse 0:2e5e65a6fb30 792 if (norm == 0.0f) return; // handle NaN
onehorse 0:2e5e65a6fb30 793 norm = 1.0f/norm;
onehorse 0:2e5e65a6fb30 794 mx *= norm;
onehorse 0:2e5e65a6fb30 795 my *= norm;
onehorse 0:2e5e65a6fb30 796 mz *= norm;
onehorse 0:2e5e65a6fb30 797
onehorse 0:2e5e65a6fb30 798 // Reference direction of Earth's magnetic field
onehorse 0:2e5e65a6fb30 799 _2q1mx = 2.0f * q1 * mx;
onehorse 0:2e5e65a6fb30 800 _2q1my = 2.0f * q1 * my;
onehorse 0:2e5e65a6fb30 801 _2q1mz = 2.0f * q1 * mz;
onehorse 0:2e5e65a6fb30 802 _2q2mx = 2.0f * q2 * mx;
onehorse 0:2e5e65a6fb30 803 hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4;
onehorse 0:2e5e65a6fb30 804 hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4;
onehorse 0:2e5e65a6fb30 805 _2bx = sqrt(hx * hx + hy * hy);
onehorse 0:2e5e65a6fb30 806 _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4;
onehorse 0:2e5e65a6fb30 807 _4bx = 2.0f * _2bx;
onehorse 0:2e5e65a6fb30 808 _4bz = 2.0f * _2bz;
onehorse 0:2e5e65a6fb30 809
onehorse 0:2e5e65a6fb30 810 // Gradient decent algorithm corrective step
onehorse 0:2e5e65a6fb30 811 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);
onehorse 0:2e5e65a6fb30 812 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);
onehorse 0:2e5e65a6fb30 813 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);
onehorse 0:2e5e65a6fb30 814 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);
onehorse 4:8d11bfc7cac0 815 norm = sqrtf(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude
onehorse 0:2e5e65a6fb30 816 norm = 1.0f/norm;
onehorse 0:2e5e65a6fb30 817 s1 *= norm;
onehorse 0:2e5e65a6fb30 818 s2 *= norm;
onehorse 0:2e5e65a6fb30 819 s3 *= norm;
onehorse 0:2e5e65a6fb30 820 s4 *= norm;
onehorse 0:2e5e65a6fb30 821
onehorse 0:2e5e65a6fb30 822 // Compute rate of change of quaternion
onehorse 0:2e5e65a6fb30 823 qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1;
onehorse 0:2e5e65a6fb30 824 qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2;
onehorse 0:2e5e65a6fb30 825 qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3;
onehorse 0:2e5e65a6fb30 826 qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4;
onehorse 0:2e5e65a6fb30 827
onehorse 0:2e5e65a6fb30 828 // Integrate to yield quaternion
onehorse 0:2e5e65a6fb30 829 q1 += qDot1 * deltat;
onehorse 0:2e5e65a6fb30 830 q2 += qDot2 * deltat;
onehorse 0:2e5e65a6fb30 831 q3 += qDot3 * deltat;
onehorse 0:2e5e65a6fb30 832 q4 += qDot4 * deltat;
onehorse 4:8d11bfc7cac0 833 norm = sqrtf(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
onehorse 0:2e5e65a6fb30 834 norm = 1.0f/norm;
onehorse 0:2e5e65a6fb30 835 q[0] = q1 * norm;
onehorse 0:2e5e65a6fb30 836 q[1] = q2 * norm;
onehorse 0:2e5e65a6fb30 837 q[2] = q3 * norm;
onehorse 0:2e5e65a6fb30 838 q[3] = q4 * norm;
onehorse 0:2e5e65a6fb30 839
onehorse 0:2e5e65a6fb30 840 }
onehorse 0:2e5e65a6fb30 841
onehorse 0:2e5e65a6fb30 842
onehorse 0:2e5e65a6fb30 843
onehorse 0:2e5e65a6fb30 844 // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and
onehorse 0:2e5e65a6fb30 845 // measured ones.
onehorse 0:2e5e65a6fb30 846 void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
onehorse 0:2e5e65a6fb30 847 {
onehorse 0:2e5e65a6fb30 848 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
onehorse 0:2e5e65a6fb30 849 float norm;
onehorse 0:2e5e65a6fb30 850 float hx, hy, bx, bz;
onehorse 0:2e5e65a6fb30 851 float vx, vy, vz, wx, wy, wz;
onehorse 0:2e5e65a6fb30 852 float ex, ey, ez;
onehorse 0:2e5e65a6fb30 853 float pa, pb, pc;
onehorse 0:2e5e65a6fb30 854
onehorse 0:2e5e65a6fb30 855 // Auxiliary variables to avoid repeated arithmetic
onehorse 0:2e5e65a6fb30 856 float q1q1 = q1 * q1;
onehorse 0:2e5e65a6fb30 857 float q1q2 = q1 * q2;
onehorse 0:2e5e65a6fb30 858 float q1q3 = q1 * q3;
onehorse 0:2e5e65a6fb30 859 float q1q4 = q1 * q4;
onehorse 0:2e5e65a6fb30 860 float q2q2 = q2 * q2;
onehorse 0:2e5e65a6fb30 861 float q2q3 = q2 * q3;
onehorse 0:2e5e65a6fb30 862 float q2q4 = q2 * q4;
onehorse 0:2e5e65a6fb30 863 float q3q3 = q3 * q3;
onehorse 0:2e5e65a6fb30 864 float q3q4 = q3 * q4;
onehorse 0:2e5e65a6fb30 865 float q4q4 = q4 * q4;
onehorse 0:2e5e65a6fb30 866
onehorse 0:2e5e65a6fb30 867 // Normalise accelerometer measurement
onehorse 4:8d11bfc7cac0 868 norm = sqrtf(ax * ax + ay * ay + az * az);
onehorse 0:2e5e65a6fb30 869 if (norm == 0.0f) return; // handle NaN
onehorse 0:2e5e65a6fb30 870 norm = 1.0f / norm; // use reciprocal for division
onehorse 0:2e5e65a6fb30 871 ax *= norm;
onehorse 0:2e5e65a6fb30 872 ay *= norm;
onehorse 0:2e5e65a6fb30 873 az *= norm;
onehorse 0:2e5e65a6fb30 874
onehorse 0:2e5e65a6fb30 875 // Normalise magnetometer measurement
onehorse 4:8d11bfc7cac0 876 norm = sqrtf(mx * mx + my * my + mz * mz);
onehorse 0:2e5e65a6fb30 877 if (norm == 0.0f) return; // handle NaN
onehorse 0:2e5e65a6fb30 878 norm = 1.0f / norm; // use reciprocal for division
onehorse 0:2e5e65a6fb30 879 mx *= norm;
onehorse 0:2e5e65a6fb30 880 my *= norm;
onehorse 0:2e5e65a6fb30 881 mz *= norm;
onehorse 0:2e5e65a6fb30 882
onehorse 0:2e5e65a6fb30 883 // Reference direction of Earth's magnetic field
onehorse 0:2e5e65a6fb30 884 hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3);
onehorse 0:2e5e65a6fb30 885 hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2);
onehorse 4:8d11bfc7cac0 886 bx = sqrtf((hx * hx) + (hy * hy));
onehorse 0:2e5e65a6fb30 887 bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3);
onehorse 0:2e5e65a6fb30 888
onehorse 0:2e5e65a6fb30 889 // Estimated direction of gravity and magnetic field
onehorse 0:2e5e65a6fb30 890 vx = 2.0f * (q2q4 - q1q3);
onehorse 0:2e5e65a6fb30 891 vy = 2.0f * (q1q2 + q3q4);
onehorse 0:2e5e65a6fb30 892 vz = q1q1 - q2q2 - q3q3 + q4q4;
onehorse 0:2e5e65a6fb30 893 wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3);
onehorse 0:2e5e65a6fb30 894 wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4);
onehorse 0:2e5e65a6fb30 895 wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3);
onehorse 0:2e5e65a6fb30 896
onehorse 0:2e5e65a6fb30 897 // Error is cross product between estimated direction and measured direction of gravity
onehorse 0:2e5e65a6fb30 898 ex = (ay * vz - az * vy) + (my * wz - mz * wy);
onehorse 0:2e5e65a6fb30 899 ey = (az * vx - ax * vz) + (mz * wx - mx * wz);
onehorse 0:2e5e65a6fb30 900 ez = (ax * vy - ay * vx) + (mx * wy - my * wx);
onehorse 0:2e5e65a6fb30 901 if (Ki > 0.0f)
onehorse 0:2e5e65a6fb30 902 {
onehorse 0:2e5e65a6fb30 903 eInt[0] += ex; // accumulate integral error
onehorse 0:2e5e65a6fb30 904 eInt[1] += ey;
onehorse 0:2e5e65a6fb30 905 eInt[2] += ez;
onehorse 0:2e5e65a6fb30 906 }
onehorse 0:2e5e65a6fb30 907 else
onehorse 0:2e5e65a6fb30 908 {
onehorse 0:2e5e65a6fb30 909 eInt[0] = 0.0f; // prevent integral wind up
onehorse 0:2e5e65a6fb30 910 eInt[1] = 0.0f;
onehorse 0:2e5e65a6fb30 911 eInt[2] = 0.0f;
onehorse 0:2e5e65a6fb30 912 }
onehorse 0:2e5e65a6fb30 913
onehorse 0:2e5e65a6fb30 914 // Apply feedback terms
onehorse 0:2e5e65a6fb30 915 gx = gx + Kp * ex + Ki * eInt[0];
onehorse 0:2e5e65a6fb30 916 gy = gy + Kp * ey + Ki * eInt[1];
onehorse 0:2e5e65a6fb30 917 gz = gz + Kp * ez + Ki * eInt[2];
onehorse 0:2e5e65a6fb30 918
onehorse 0:2e5e65a6fb30 919 // Integrate rate of change of quaternion
onehorse 0:2e5e65a6fb30 920 pa = q2;
onehorse 0:2e5e65a6fb30 921 pb = q3;
onehorse 0:2e5e65a6fb30 922 pc = q4;
onehorse 0:2e5e65a6fb30 923 q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat);
onehorse 0:2e5e65a6fb30 924 q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat);
onehorse 0:2e5e65a6fb30 925 q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat);
onehorse 0:2e5e65a6fb30 926 q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat);
onehorse 0:2e5e65a6fb30 927
onehorse 0:2e5e65a6fb30 928 // Normalise quaternion
onehorse 4:8d11bfc7cac0 929 norm = sqrtf(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);
onehorse 0:2e5e65a6fb30 930 norm = 1.0f / norm;
onehorse 0:2e5e65a6fb30 931 q[0] = q1 * norm;
onehorse 0:2e5e65a6fb30 932 q[1] = q2 * norm;
onehorse 0:2e5e65a6fb30 933 q[2] = q3 * norm;
onehorse 0:2e5e65a6fb30 934 q[3] = q4 * norm;
onehorse 0:2e5e65a6fb30 935
onehorse 0:2e5e65a6fb30 936 }
onehorse 0:2e5e65a6fb30 937 };
onehorse 0:2e5e65a6fb30 938 #endif