Janek Mann / MPU9250AHRS-cleaned

Library version of MPU9250AHRS code.

Fork of MPU9250AHRS by Janek Mann

MPU9250.h@4:404c35f32ce3, 2014-09-04 (annotated)

Committer:
janekm
Date:
Thu Sep 04 21:19:05 2014 +0000
Revision:
4:404c35f32ce3
Parent:
3:c05fbe0aef1f
Child:
5:ea541d293095
turning it into more of a library...

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
janekm 3:c05fbe0aef1f 3
onehorse 0:2e5e65a6fb30 4 #include "mbed.h"
onehorse 0:2e5e65a6fb30 5 #include "math.h"
janekm 3:c05fbe0aef1f 6
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 29 #define SELF_TEST_X_GYRO 0x00
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 60 #define LP_ACCEL_ODR 0x1E
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 164 #endif
onehorse 0:2e5e65a6fb30 165
onehorse 0:2e5e65a6fb30 166 // Set initial input parameters
onehorse 0:2e5e65a6fb30 167 enum Ascale {
janekm 3:c05fbe0aef1f 168 AFS_2G = 0,
janekm 3:c05fbe0aef1f 169 AFS_4G,
janekm 3:c05fbe0aef1f 170 AFS_8G,
janekm 3:c05fbe0aef1f 171 AFS_16G
onehorse 0:2e5e65a6fb30 172 };
onehorse 0:2e5e65a6fb30 173
onehorse 0:2e5e65a6fb30 174 enum Gscale {
janekm 3:c05fbe0aef1f 175 GFS_250DPS = 0,
janekm 3:c05fbe0aef1f 176 GFS_500DPS,
janekm 3:c05fbe0aef1f 177 GFS_1000DPS,
janekm 3:c05fbe0aef1f 178 GFS_2000DPS
onehorse 0:2e5e65a6fb30 179 };
onehorse 0:2e5e65a6fb30 180
onehorse 0:2e5e65a6fb30 181 enum Mscale {
janekm 3:c05fbe0aef1f 182 MFS_14BITS = 0, // 0.6 mG per LSB
janekm 3:c05fbe0aef1f 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
janekm 3:c05fbe0aef1f 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)
janekm 4:404c35f32ce3 193 //I2C i2c(I2C_SDA, I2C_SCL);
onehorse 0:2e5e65a6fb30 194
janekm 4:404c35f32ce3 195 //DigitalOut myled(LED1);
janekm 3:c05fbe0aef1f 196
onehorse 0:2e5e65a6fb30 197 // Pin definitions
janekm 4:404c35f32ce3 198 //int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins
onehorse 0:2e5e65a6fb30 199
onehorse 0:2e5e65a6fb30 200 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
onehorse 0:2e5e65a6fb30 201 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
onehorse 0:2e5e65a6fb30 202 int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output
onehorse 0:2e5e65a6fb30 203 float magCalibration[3] = {0, 0, 0}, magbias[3] = {0, 0, 0}; // Factory mag calibration and mag bias
onehorse 0:2e5e65a6fb30 204 float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer
janekm 3:c05fbe0aef1f 205 float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
onehorse 0:2e5e65a6fb30 206 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
onehorse 0:2e5e65a6fb30 207 float temperature;
onehorse 0:2e5e65a6fb30 208 float SelfTest[6];
onehorse 0:2e5e65a6fb30 209
onehorse 0:2e5e65a6fb30 210 int delt_t = 0; // used to control display output rate
onehorse 0:2e5e65a6fb30 211 int count = 0; // used to control display output rate
onehorse 0:2e5e65a6fb30 212
onehorse 0:2e5e65a6fb30 213 // parameters for 6 DoF sensor fusion calculations
onehorse 0:2e5e65a6fb30 214 float PI = 3.14159265358979323846f;
onehorse 0:2e5e65a6fb30 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
onehorse 0:2e5e65a6fb30 216 float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
onehorse 0:2e5e65a6fb30 217 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
onehorse 0:2e5e65a6fb30 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
onehorse 0:2e5e65a6fb30 219
onehorse 0:2e5e65a6fb30 220 float pitch, yaw, roll;
onehorse 0:2e5e65a6fb30 221 float deltat = 0.0f; // integration interval for both filter schemes
onehorse 0:2e5e65a6fb30 222 int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval
onehorse 0:2e5e65a6fb30 223 float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method
onehorse 0:2e5e65a6fb30 224
janekm 3:c05fbe0aef1f 225 class MPU9250
janekm 3:c05fbe0aef1f 226 {
janekm 3:c05fbe0aef1f 227
janekm 3:c05fbe0aef1f 228 protected:
janekm 3:c05fbe0aef1f 229 I2C* _i2c;
janekm 3:c05fbe0aef1f 230
janekm 3:c05fbe0aef1f 231 public:
janekm 3:c05fbe0aef1f 232 //===================================================================================================================
onehorse 0:2e5e65a6fb30 233 //====== Set of useful function to access acceleratio, gyroscope, and temperature data
onehorse 0:2e5e65a6fb30 234 //===================================================================================================================
janekm 4:404c35f32ce3 235 MPU9250(I2C *i2c) : _i2c( i2c ) {
janekm 4:404c35f32ce3 236
janekm 3:c05fbe0aef1f 237 }
janekm 3:c05fbe0aef1f 238
janekm 3:c05fbe0aef1f 239 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data) {
janekm 3:c05fbe0aef1f 240 char data_write[2];
janekm 3:c05fbe0aef1f 241 data_write[0] = subAddress;
janekm 3:c05fbe0aef1f 242 data_write[1] = data;
janekm 3:c05fbe0aef1f 243 _i2c->write(address, data_write, 2, 0);
janekm 3:c05fbe0aef1f 244 }
onehorse 0:2e5e65a6fb30 245
janekm 3:c05fbe0aef1f 246 char readByte(uint8_t address, uint8_t subAddress) {
janekm 3:c05fbe0aef1f 247 char data[1]; // `data` will store the register data
janekm 3:c05fbe0aef1f 248 char data_write[1];
janekm 3:c05fbe0aef1f 249 data_write[0] = subAddress;
janekm 3:c05fbe0aef1f 250 _i2c->write(address, data_write, 1, 1); // no stop
janekm 3:c05fbe0aef1f 251 _i2c->read(address, data, 1, 0);
janekm 3:c05fbe0aef1f 252 return data[0];
onehorse 0:2e5e65a6fb30 253 }
onehorse 0:2e5e65a6fb30 254
janekm 3:c05fbe0aef1f 255 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) {
janekm 3:c05fbe0aef1f 256 char data[14];
janekm 3:c05fbe0aef1f 257 char data_write[1];
janekm 3:c05fbe0aef1f 258 data_write[0] = subAddress;
janekm 3:c05fbe0aef1f 259 _i2c->write(address, data_write, 1, 1); // no stop
janekm 3:c05fbe0aef1f 260 _i2c->read(address, data, count, 0);
janekm 3:c05fbe0aef1f 261 for(int ii = 0; ii < count; ii++) {
janekm 3:c05fbe0aef1f 262 dest[ii] = data[ii];
janekm 3:c05fbe0aef1f 263 }
janekm 3:c05fbe0aef1f 264 }
onehorse 0:2e5e65a6fb30 265
onehorse 0:2e5e65a6fb30 266
janekm 3:c05fbe0aef1f 267 void getMres() {
janekm 3:c05fbe0aef1f 268 switch (Mscale) {
janekm 3:c05fbe0aef1f 269 // Possible magnetometer scales (and their register bit settings) are:
janekm 3:c05fbe0aef1f 270 // 14 bit resolution (0) and 16 bit resolution (1)
janekm 3:c05fbe0aef1f 271 case MFS_14BITS:
janekm 3:c05fbe0aef1f 272 mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss
janekm 3:c05fbe0aef1f 273 break;
janekm 3:c05fbe0aef1f 274 case MFS_16BITS:
janekm 3:c05fbe0aef1f 275 mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss
janekm 3:c05fbe0aef1f 276 break;
janekm 3:c05fbe0aef1f 277 }
janekm 3:c05fbe0aef1f 278 }
onehorse 0:2e5e65a6fb30 279
onehorse 0:2e5e65a6fb30 280
janekm 3:c05fbe0aef1f 281 void getGres() {
janekm 3:c05fbe0aef1f 282 switch (Gscale) {
janekm 3:c05fbe0aef1f 283 // Possible gyro scales (and their register bit settings) are:
janekm 3:c05fbe0aef1f 284 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
janekm 3:c05fbe0aef1f 285 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
janekm 3:c05fbe0aef1f 286 case GFS_250DPS:
janekm 3:c05fbe0aef1f 287 gRes = 250.0/32768.0;
janekm 3:c05fbe0aef1f 288 break;
janekm 3:c05fbe0aef1f 289 case GFS_500DPS:
janekm 3:c05fbe0aef1f 290 gRes = 500.0/32768.0;
janekm 3:c05fbe0aef1f 291 break;
janekm 3:c05fbe0aef1f 292 case GFS_1000DPS:
janekm 3:c05fbe0aef1f 293 gRes = 1000.0/32768.0;
janekm 3:c05fbe0aef1f 294 break;
janekm 3:c05fbe0aef1f 295 case GFS_2000DPS:
janekm 3:c05fbe0aef1f 296 gRes = 2000.0/32768.0;
janekm 3:c05fbe0aef1f 297 break;
janekm 3:c05fbe0aef1f 298 }
janekm 3:c05fbe0aef1f 299 }
janekm 3:c05fbe0aef1f 300
janekm 3:c05fbe0aef1f 301
janekm 3:c05fbe0aef1f 302 void getAres() {
janekm 3:c05fbe0aef1f 303 switch (Ascale) {
janekm 3:c05fbe0aef1f 304 // Possible accelerometer scales (and their register bit settings) are:
janekm 3:c05fbe0aef1f 305 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
janekm 3:c05fbe0aef1f 306 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
janekm 3:c05fbe0aef1f 307 case AFS_2G:
janekm 3:c05fbe0aef1f 308 aRes = 2.0/32768.0;
janekm 3:c05fbe0aef1f 309 break;
janekm 3:c05fbe0aef1f 310 case AFS_4G:
janekm 3:c05fbe0aef1f 311 aRes = 4.0/32768.0;
janekm 3:c05fbe0aef1f 312 break;
janekm 3:c05fbe0aef1f 313 case AFS_8G:
janekm 3:c05fbe0aef1f 314 aRes = 8.0/32768.0;
janekm 3:c05fbe0aef1f 315 break;
janekm 3:c05fbe0aef1f 316 case AFS_16G:
janekm 3:c05fbe0aef1f 317 aRes = 16.0/32768.0;
janekm 3:c05fbe0aef1f 318 break;
janekm 3:c05fbe0aef1f 319 }
janekm 3:c05fbe0aef1f 320 }
onehorse 0:2e5e65a6fb30 321
onehorse 0:2e5e65a6fb30 322
janekm 3:c05fbe0aef1f 323 void readAccelData(int16_t * destination) {
janekm 3:c05fbe0aef1f 324 uint8_t rawData[6]; // x/y/z accel register data stored here
janekm 3:c05fbe0aef1f 325 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
janekm 3:c05fbe0aef1f 326 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
janekm 3:c05fbe0aef1f 327 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
janekm 3:c05fbe0aef1f 328 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
janekm 3:c05fbe0aef1f 329 }
onehorse 0:2e5e65a6fb30 330
janekm 3:c05fbe0aef1f 331 void readGyroData(int16_t * destination) {
janekm 3:c05fbe0aef1f 332 uint8_t rawData[6]; // x/y/z gyro register data stored here
janekm 3:c05fbe0aef1f 333 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
janekm 3:c05fbe0aef1f 334 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
janekm 3:c05fbe0aef1f 335 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
janekm 3:c05fbe0aef1f 336 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
janekm 3:c05fbe0aef1f 337 }
onehorse 0:2e5e65a6fb30 338
janekm 3:c05fbe0aef1f 339 void readMagData(int16_t * destination) {
janekm 3:c05fbe0aef1f 340 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
janekm 3:c05fbe0aef1f 341 if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set
janekm 3:c05fbe0aef1f 342 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
janekm 3:c05fbe0aef1f 343 uint8_t c = rawData[6]; // End data read by reading ST2 register
janekm 3:c05fbe0aef1f 344 if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data
janekm 3:c05fbe0aef1f 345 destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value
janekm 3:c05fbe0aef1f 346 destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian
janekm 3:c05fbe0aef1f 347 destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ;
janekm 3:c05fbe0aef1f 348 }
janekm 3:c05fbe0aef1f 349 }
janekm 3:c05fbe0aef1f 350 }
onehorse 0:2e5e65a6fb30 351
janekm 3:c05fbe0aef1f 352 int16_t readTempData() {
janekm 3:c05fbe0aef1f 353 uint8_t rawData[2]; // x/y/z gyro register data stored here
janekm 3:c05fbe0aef1f 354 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
janekm 3:c05fbe0aef1f 355 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
janekm 3:c05fbe0aef1f 356 }
onehorse 0:2e5e65a6fb30 357
onehorse 0:2e5e65a6fb30 358
janekm 3:c05fbe0aef1f 359 void resetMPU9250() {
janekm 3:c05fbe0aef1f 360 // reset device
janekm 3:c05fbe0aef1f 361 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
janekm 3:c05fbe0aef1f 362 wait(0.1);
janekm 3:c05fbe0aef1f 363 }
janekm 3:c05fbe0aef1f 364
janekm 3:c05fbe0aef1f 365 void initAK8963(float * destination) {
janekm 3:c05fbe0aef1f 366 // First extract the factory calibration for each magnetometer axis
janekm 3:c05fbe0aef1f 367 uint8_t rawData[3]; // x/y/z gyro calibration data stored here
janekm 3:c05fbe0aef1f 368 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
janekm 3:c05fbe0aef1f 369 wait(0.01);
janekm 3:c05fbe0aef1f 370 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
janekm 3:c05fbe0aef1f 371 wait(0.01);
janekm 3:c05fbe0aef1f 372 readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
janekm 3:c05fbe0aef1f 373 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
janekm 3:c05fbe0aef1f 374 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
janekm 3:c05fbe0aef1f 375 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
janekm 3:c05fbe0aef1f 376 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
janekm 3:c05fbe0aef1f 377 wait(0.01);
janekm 3:c05fbe0aef1f 378 // Configure the magnetometer for continuous read and highest resolution
janekm 3:c05fbe0aef1f 379 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
janekm 3:c05fbe0aef1f 380 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
janekm 3:c05fbe0aef1f 381 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
janekm 3:c05fbe0aef1f 382 wait(0.01);
janekm 3:c05fbe0aef1f 383 }
onehorse 0:2e5e65a6fb30 384
onehorse 0:2e5e65a6fb30 385
janekm 3:c05fbe0aef1f 386 void initMPU9250() {
janekm 3:c05fbe0aef1f 387 // Initialize MPU9250 device
janekm 3:c05fbe0aef1f 388 // wake up device
janekm 3:c05fbe0aef1f 389 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
janekm 3:c05fbe0aef1f 390 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
janekm 3:c05fbe0aef1f 391
janekm 3:c05fbe0aef1f 392 // get stable time source
janekm 3:c05fbe0aef1f 393 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 394
janekm 3:c05fbe0aef1f 395 // Configure Gyro and Accelerometer
janekm 3:c05fbe0aef1f 396 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
janekm 3:c05fbe0aef1f 397 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
janekm 3:c05fbe0aef1f 398 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
janekm 3:c05fbe0aef1f 399 writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
janekm 3:c05fbe0aef1f 400
janekm 3:c05fbe0aef1f 401 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
janekm 3:c05fbe0aef1f 402 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
onehorse 0:2e5e65a6fb30 403
janekm 3:c05fbe0aef1f 404 // Set gyroscope full scale range
janekm 3:c05fbe0aef1f 405 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
janekm 3:c05fbe0aef1f 406 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
janekm 3:c05fbe0aef1f 407 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
janekm 3:c05fbe0aef1f 408 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
janekm 3:c05fbe0aef1f 409 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
janekm 3:c05fbe0aef1f 410
janekm 3:c05fbe0aef1f 411 // Set accelerometer configuration
janekm 3:c05fbe0aef1f 412 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
janekm 3:c05fbe0aef1f 413 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
janekm 3:c05fbe0aef1f 414 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
janekm 3:c05fbe0aef1f 415 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
onehorse 0:2e5e65a6fb30 416
janekm 3:c05fbe0aef1f 417 // Set accelerometer sample rate configuration
janekm 3:c05fbe0aef1f 418 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
janekm 3:c05fbe0aef1f 419 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
janekm 3:c05fbe0aef1f 420 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
janekm 3:c05fbe0aef1f 421 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
janekm 3:c05fbe0aef1f 422 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
onehorse 0:2e5e65a6fb30 423
janekm 3:c05fbe0aef1f 424 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
janekm 3:c05fbe0aef1f 425 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
onehorse 0:2e5e65a6fb30 426
janekm 3:c05fbe0aef1f 427 // Configure Interrupts and Bypass Enable
janekm 3:c05fbe0aef1f 428 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
janekm 3:c05fbe0aef1f 429 // can join the I2C bus and all can be controlled by the Arduino as master
janekm 3:c05fbe0aef1f 430 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
janekm 3:c05fbe0aef1f 431 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
janekm 3:c05fbe0aef1f 432 }
onehorse 0:2e5e65a6fb30 433
onehorse 0:2e5e65a6fb30 434 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
onehorse 0:2e5e65a6fb30 435 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
janekm 3:c05fbe0aef1f 436 void calibrateMPU9250(float * dest1, float * dest2) {
janekm 3:c05fbe0aef1f 437 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
janekm 3:c05fbe0aef1f 438 uint16_t ii, packet_count, fifo_count;
janekm 3:c05fbe0aef1f 439 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
janekm 3:c05fbe0aef1f 440
onehorse 0:2e5e65a6fb30 441 // reset device, reset all registers, clear gyro and accelerometer bias registers
janekm 3:c05fbe0aef1f 442 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
janekm 3:c05fbe0aef1f 443 wait(0.1);
janekm 3:c05fbe0aef1f 444
onehorse 0:2e5e65a6fb30 445 // get stable time source
onehorse 0:2e5e65a6fb30 446 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
janekm 3:c05fbe0aef1f 447 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
janekm 3:c05fbe0aef1f 448 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
janekm 3:c05fbe0aef1f 449 wait(0.2);
janekm 3:c05fbe0aef1f 450
onehorse 0:2e5e65a6fb30 451 // Configure device for bias calculation
janekm 3:c05fbe0aef1f 452 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
janekm 3:c05fbe0aef1f 453 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
janekm 3:c05fbe0aef1f 454 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
janekm 3:c05fbe0aef1f 455 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
janekm 3:c05fbe0aef1f 456 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
janekm 3:c05fbe0aef1f 457 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
janekm 3:c05fbe0aef1f 458 wait(0.015);
janekm 3:c05fbe0aef1f 459
onehorse 0:2e5e65a6fb30 460 // Configure MPU9250 gyro and accelerometer for bias calculation
janekm 3:c05fbe0aef1f 461 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
janekm 3:c05fbe0aef1f 462 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
janekm 3:c05fbe0aef1f 463 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
janekm 3:c05fbe0aef1f 464 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
janekm 3:c05fbe0aef1f 465
janekm 3:c05fbe0aef1f 466 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
janekm 3:c05fbe0aef1f 467 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
onehorse 0:2e5e65a6fb30 468
onehorse 0:2e5e65a6fb30 469 // Configure FIFO to capture accelerometer and gyro data for bias calculation
janekm 3:c05fbe0aef1f 470 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
janekm 3:c05fbe0aef1f 471 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
janekm 3:c05fbe0aef1f 472 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
onehorse 0:2e5e65a6fb30 473
onehorse 0:2e5e65a6fb30 474 // At end of sample accumulation, turn off FIFO sensor read
janekm 3:c05fbe0aef1f 475 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
janekm 3:c05fbe0aef1f 476 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
janekm 3:c05fbe0aef1f 477 fifo_count = ((uint16_t)data[0] << 8) | data[1];
janekm 3:c05fbe0aef1f 478 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
janekm 3:c05fbe0aef1f 479
janekm 3:c05fbe0aef1f 480 for (ii = 0; ii < packet_count; ii++) {
janekm 3:c05fbe0aef1f 481 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
janekm 3:c05fbe0aef1f 482 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
janekm 3:c05fbe0aef1f 483 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
janekm 3:c05fbe0aef1f 484 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
janekm 3:c05fbe0aef1f 485 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
janekm 3:c05fbe0aef1f 486 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
janekm 3:c05fbe0aef1f 487 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
janekm 3:c05fbe0aef1f 488 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
janekm 3:c05fbe0aef1f 489
janekm 3:c05fbe0aef1f 490 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
janekm 3:c05fbe0aef1f 491 accel_bias[1] += (int32_t) accel_temp[1];
janekm 3:c05fbe0aef1f 492 accel_bias[2] += (int32_t) accel_temp[2];
janekm 3:c05fbe0aef1f 493 gyro_bias[0] += (int32_t) gyro_temp[0];
janekm 3:c05fbe0aef1f 494 gyro_bias[1] += (int32_t) gyro_temp[1];
janekm 3:c05fbe0aef1f 495 gyro_bias[2] += (int32_t) gyro_temp[2];
onehorse 0:2e5e65a6fb30 496
janekm 3:c05fbe0aef1f 497 }
janekm 3:c05fbe0aef1f 498 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
janekm 3:c05fbe0aef1f 499 accel_bias[1] /= (int32_t) packet_count;
janekm 3:c05fbe0aef1f 500 accel_bias[2] /= (int32_t) packet_count;
janekm 3:c05fbe0aef1f 501 gyro_bias[0] /= (int32_t) packet_count;
janekm 3:c05fbe0aef1f 502 gyro_bias[1] /= (int32_t) packet_count;
janekm 3:c05fbe0aef1f 503 gyro_bias[2] /= (int32_t) packet_count;
janekm 3:c05fbe0aef1f 504
janekm 3:c05fbe0aef1f 505 if(accel_bias[2] > 0L) {
janekm 3:c05fbe0aef1f 506 accel_bias[2] -= (int32_t) accelsensitivity; // Remove gravity from the z-axis accelerometer bias calculation
janekm 3:c05fbe0aef1f 507 } else {
janekm 3:c05fbe0aef1f 508 accel_bias[2] += (int32_t) accelsensitivity;
janekm 3:c05fbe0aef1f 509 }
janekm 3:c05fbe0aef1f 510
onehorse 0:2e5e65a6fb30 511 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
janekm 3:c05fbe0aef1f 512 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
janekm 3:c05fbe0aef1f 513 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
janekm 3:c05fbe0aef1f 514 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
janekm 3:c05fbe0aef1f 515 data[3] = (-gyro_bias[1]/4) & 0xFF;
janekm 3:c05fbe0aef1f 516 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
janekm 3:c05fbe0aef1f 517 data[5] = (-gyro_bias[2]/4) & 0xFF;
onehorse 0:2e5e65a6fb30 518
onehorse 0:2e5e65a6fb30 519 /// Push gyro biases to hardware registers
janekm 3:c05fbe0aef1f 520 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
janekm 3:c05fbe0aef1f 521 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
janekm 3:c05fbe0aef1f 522 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
janekm 3:c05fbe0aef1f 523 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
janekm 3:c05fbe0aef1f 524 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
janekm 3:c05fbe0aef1f 525 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);
janekm 3:c05fbe0aef1f 526 */
janekm 3:c05fbe0aef1f 527 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
janekm 3:c05fbe0aef1f 528 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
janekm 3:c05fbe0aef1f 529 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
onehorse 0:2e5e65a6fb30 530
onehorse 0:2e5e65a6fb30 531 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
onehorse 0:2e5e65a6fb30 532 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
onehorse 0:2e5e65a6fb30 533 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
onehorse 0:2e5e65a6fb30 534 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
onehorse 0:2e5e65a6fb30 535 // the accelerometer biases calculated above must be divided by 8.
onehorse 0:2e5e65a6fb30 536
janekm 3:c05fbe0aef1f 537 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
janekm 3:c05fbe0aef1f 538 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
janekm 3:c05fbe0aef1f 539 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
janekm 3:c05fbe0aef1f 540 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
janekm 3:c05fbe0aef1f 541 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
janekm 3:c05fbe0aef1f 542 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
janekm 3:c05fbe0aef1f 543 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
janekm 3:c05fbe0aef1f 544
janekm 3:c05fbe0aef1f 545 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
janekm 3:c05fbe0aef1f 546 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
janekm 3:c05fbe0aef1f 547
janekm 3:c05fbe0aef1f 548 for(ii = 0; ii < 3; ii++) {
janekm 3:c05fbe0aef1f 549 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
janekm 3:c05fbe0aef1f 550 }
onehorse 0:2e5e65a6fb30 551
janekm 3:c05fbe0aef1f 552 // Construct total accelerometer bias, including calculated average accelerometer bias from above
janekm 3:c05fbe0aef1f 553 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
janekm 3:c05fbe0aef1f 554 accel_bias_reg[1] -= (accel_bias[1]/8);
janekm 3:c05fbe0aef1f 555 accel_bias_reg[2] -= (accel_bias[2]/8);
janekm 3:c05fbe0aef1f 556
janekm 3:c05fbe0aef1f 557 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
janekm 3:c05fbe0aef1f 558 data[1] = (accel_bias_reg[0]) & 0xFF;
janekm 3:c05fbe0aef1f 559 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
janekm 3:c05fbe0aef1f 560 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
janekm 3:c05fbe0aef1f 561 data[3] = (accel_bias_reg[1]) & 0xFF;
janekm 3:c05fbe0aef1f 562 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
janekm 3:c05fbe0aef1f 563 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
janekm 3:c05fbe0aef1f 564 data[5] = (accel_bias_reg[2]) & 0xFF;
janekm 3:c05fbe0aef1f 565 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
onehorse 0:2e5e65a6fb30 566
onehorse 0:2e5e65a6fb30 567 // Apparently this is not working for the acceleration biases in the MPU-9250
onehorse 0:2e5e65a6fb30 568 // Are we handling the temperature correction bit properly?
onehorse 0:2e5e65a6fb30 569 // Push accelerometer biases to hardware registers
janekm 3:c05fbe0aef1f 570 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
janekm 3:c05fbe0aef1f 571 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
janekm 3:c05fbe0aef1f 572 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
janekm 3:c05fbe0aef1f 573 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
janekm 3:c05fbe0aef1f 574 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
janekm 3:c05fbe0aef1f 575 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);
janekm 3:c05fbe0aef1f 576 */
onehorse 0:2e5e65a6fb30 577 // Output scaled accelerometer biases for manual subtraction in the main program
janekm 3:c05fbe0aef1f 578 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity;
janekm 3:c05fbe0aef1f 579 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity;
janekm 3:c05fbe0aef1f 580 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
janekm 3:c05fbe0aef1f 581 }
onehorse 0:2e5e65a6fb30 582
onehorse 0:2e5e65a6fb30 583
onehorse 0:2e5e65a6fb30 584 // Accelerometer and gyroscope self test; check calibration wrt factory settings
janekm 3:c05fbe0aef1f 585 void MPU9250SelfTest(float * destination) { // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
janekm 3:c05fbe0aef1f 586 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
janekm 3:c05fbe0aef1f 587 uint8_t selfTest[6];
janekm 3:c05fbe0aef1f 588 int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3];
janekm 3:c05fbe0aef1f 589 float factoryTrim[6];
janekm 3:c05fbe0aef1f 590 uint8_t FS = 0;
janekm 3:c05fbe0aef1f 591
janekm 3:c05fbe0aef1f 592 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
janekm 3:c05fbe0aef1f 593 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
janekm 3:c05fbe0aef1f 594 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
janekm 3:c05fbe0aef1f 595 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
janekm 3:c05fbe0aef1f 596 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
janekm 3:c05fbe0aef1f 597
janekm 3:c05fbe0aef1f 598 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
onehorse 2:4e59a37182df 599
janekm 3:c05fbe0aef1f 600 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
janekm 3:c05fbe0aef1f 601 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
janekm 3:c05fbe0aef1f 602 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
janekm 3:c05fbe0aef1f 603 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
janekm 3:c05fbe0aef1f 604
janekm 3:c05fbe0aef1f 605 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
janekm 3:c05fbe0aef1f 606 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
janekm 3:c05fbe0aef1f 607 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
janekm 3:c05fbe0aef1f 608 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
janekm 3:c05fbe0aef1f 609 }
janekm 3:c05fbe0aef1f 610
janekm 3:c05fbe0aef1f 611 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
janekm 3:c05fbe0aef1f 612 aAvg[ii] /= 200;
janekm 3:c05fbe0aef1f 613 gAvg[ii] /= 200;
janekm 3:c05fbe0aef1f 614 }
janekm 3:c05fbe0aef1f 615
onehorse 2:4e59a37182df 616 // Configure the accelerometer for self-test
janekm 3:c05fbe0aef1f 617 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
janekm 3:c05fbe0aef1f 618 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
janekm 4:404c35f32ce3 619 wait(25); // Delay a while to let the device stabilize
janekm 3:c05fbe0aef1f 620
janekm 3:c05fbe0aef1f 621 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
onehorse 2:4e59a37182df 622
janekm 3:c05fbe0aef1f 623 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
janekm 3:c05fbe0aef1f 624 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
janekm 3:c05fbe0aef1f 625 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
janekm 3:c05fbe0aef1f 626 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
janekm 3:c05fbe0aef1f 627
janekm 3:c05fbe0aef1f 628 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
janekm 3:c05fbe0aef1f 629 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
janekm 3:c05fbe0aef1f 630 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
janekm 3:c05fbe0aef1f 631 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
janekm 3:c05fbe0aef1f 632 }
janekm 3:c05fbe0aef1f 633
janekm 3:c05fbe0aef1f 634 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
janekm 3:c05fbe0aef1f 635 aSTAvg[ii] /= 200;
janekm 3:c05fbe0aef1f 636 gSTAvg[ii] /= 200;
janekm 3:c05fbe0aef1f 637 }
janekm 3:c05fbe0aef1f 638
janekm 3:c05fbe0aef1f 639 // Configure the gyro and accelerometer for normal operation
janekm 3:c05fbe0aef1f 640 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
janekm 3:c05fbe0aef1f 641 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
janekm 4:404c35f32ce3 642 wait(25); // Delay a while to let the device stabilize
onehorse 0:2e5e65a6fb30 643
janekm 3:c05fbe0aef1f 644 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
janekm 3:c05fbe0aef1f 645 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
janekm 3:c05fbe0aef1f 646 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
janekm 3:c05fbe0aef1f 647 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
janekm 3:c05fbe0aef1f 648 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
janekm 3:c05fbe0aef1f 649 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
janekm 3:c05fbe0aef1f 650 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
janekm 3:c05fbe0aef1f 651
janekm 3:c05fbe0aef1f 652 // Retrieve factory self-test value from self-test code reads
janekm 3:c05fbe0aef1f 653 factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation
janekm 3:c05fbe0aef1f 654 factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation
janekm 3:c05fbe0aef1f 655 factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation
janekm 3:c05fbe0aef1f 656 factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation
janekm 3:c05fbe0aef1f 657 factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation
janekm 3:c05fbe0aef1f 658 factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation
janekm 3:c05fbe0aef1f 659
janekm 3:c05fbe0aef1f 660 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
janekm 3:c05fbe0aef1f 661 // To get percent, must multiply by 100
janekm 3:c05fbe0aef1f 662 for (int i = 0; i < 3; i++) {
janekm 3:c05fbe0aef1f 663 destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences
janekm 3:c05fbe0aef1f 664 destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences
janekm 3:c05fbe0aef1f 665 }
janekm 3:c05fbe0aef1f 666
janekm 3:c05fbe0aef1f 667 }
onehorse 0:2e5e65a6fb30 668
onehorse 0:2e5e65a6fb30 669
janekm 3:c05fbe0aef1f 670 };
onehorse 0:2e5e65a6fb30 671 #endif