Elizabeth Sonder / Mbed 2 deprecated IMU_serial_test

Speed testing IMUs

Dependencies:   MadgwickAHRS mbed

Fork of IMU_serial by Patrick Ciccone

MPU9250.h@0:80a695ae3cc3, 2016-09-28 (annotated)

Committer:
rctaduio
Date:
Wed Sep 28 23:59:57 2016 +0000
Revision:
0:80a695ae3cc3
Child:
3:c1902ecb30a7
stuff

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rctaduio 0:80a695ae3cc3 1 /*
rctaduio 0:80a695ae3cc3 2 TODO:
rctaduio 0:80a695ae3cc3 3 add configuration function:
rctaduio 0:80a695ae3cc3 4 loop through mux
rctaduio 0:80a695ae3cc3 5 if imu
rctaduio 0:80a695ae3cc3 6 append imu to a list
rctaduio 0:80a695ae3cc3 7 ...
rctaduio 0:80a695ae3cc3 8 ...
rctaduio 0:80a695ae3cc3 9 if list > 0
rctaduio 0:80a695ae3cc3 10 return something good
rctaduio 0:80a695ae3cc3 11
rctaduio 0:80a695ae3cc3 12 add config output function
rctaduio 0:80a695ae3cc3 13
rctaduio 0:80a695ae3cc3 14
rctaduio 0:80a695ae3cc3 15
rctaduio 0:80a695ae3cc3 16 */
rctaduio 0:80a695ae3cc3 17
rctaduio 0:80a695ae3cc3 18
rctaduio 0:80a695ae3cc3 19 #ifndef MPU9250_H
rctaduio 0:80a695ae3cc3 20 #define MPU9250_H
rctaduio 0:80a695ae3cc3 21
rctaduio 0:80a695ae3cc3 22 #include "mbed.h"
rctaduio 0:80a695ae3cc3 23 #include "math.h"
rctaduio 0:80a695ae3cc3 24 #include "MadgwickAHRS.h"
rctaduio 0:80a695ae3cc3 25
rctaduio 0:80a695ae3cc3 26 // 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
rctaduio 0:80a695ae3cc3 27 // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map
rctaduio 0:80a695ae3cc3 28 //
rctaduio 0:80a695ae3cc3 29 //Magnetometer Registers
rctaduio 0:80a695ae3cc3 30 #define AK8963_ADDRESS 0x0C<<1
rctaduio 0:80a695ae3cc3 31 #define WHO_AM_I_AK8963 0x00 // should return 0x48
rctaduio 0:80a695ae3cc3 32 #define INFO 0x01
rctaduio 0:80a695ae3cc3 33 #define AK8963_ST1 0x02 // data ready status bit 0
rctaduio 0:80a695ae3cc3 34 #define AK8963_XOUT_L 0x03 // data
rctaduio 0:80a695ae3cc3 35 #define AK8963_XOUT_H 0x04
rctaduio 0:80a695ae3cc3 36 #define AK8963_YOUT_L 0x05
rctaduio 0:80a695ae3cc3 37 #define AK8963_YOUT_H 0x06
rctaduio 0:80a695ae3cc3 38 #define AK8963_ZOUT_L 0x07
rctaduio 0:80a695ae3cc3 39 #define AK8963_ZOUT_H 0x08
rctaduio 0:80a695ae3cc3 40 #define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status bit 2
rctaduio 0:80a695ae3cc3 41 #define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001), self-test (1000) and Fuse ROM (1111) modes on bits 3:0
rctaduio 0:80a695ae3cc3 42 #define AK8963_ASTC 0x0C // Self test control
rctaduio 0:80a695ae3cc3 43 #define AK8963_I2CDIS 0x0F // I2C disable
rctaduio 0:80a695ae3cc3 44 #define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value
rctaduio 0:80a695ae3cc3 45 #define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value
rctaduio 0:80a695ae3cc3 46 #define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value
rctaduio 0:80a695ae3cc3 47
rctaduio 0:80a695ae3cc3 48 #define SELF_TEST_X_GYRO 0x00
rctaduio 0:80a695ae3cc3 49 #define SELF_TEST_Y_GYRO 0x01
rctaduio 0:80a695ae3cc3 50 #define SELF_TEST_Z_GYRO 0x02
rctaduio 0:80a695ae3cc3 51
rctaduio 0:80a695ae3cc3 52 /*#define X_FINE_GAIN 0x03 // [7:0] fine gain
rctaduio 0:80a695ae3cc3 53 #define Y_FINE_GAIN 0x04
rctaduio 0:80a695ae3cc3 54 #define Z_FINE_GAIN 0x05
rctaduio 0:80a695ae3cc3 55 #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer
rctaduio 0:80a695ae3cc3 56 #define XA_OFFSET_L_TC 0x07
rctaduio 0:80a695ae3cc3 57 #define YA_OFFSET_H 0x08
rctaduio 0:80a695ae3cc3 58 #define YA_OFFSET_L_TC 0x09
rctaduio 0:80a695ae3cc3 59 #define ZA_OFFSET_H 0x0A
rctaduio 0:80a695ae3cc3 60 #define ZA_OFFSET_L_TC 0x0B */
rctaduio 0:80a695ae3cc3 61
rctaduio 0:80a695ae3cc3 62 #define SELF_TEST_X_ACCEL 0x0D
rctaduio 0:80a695ae3cc3 63 #define SELF_TEST_Y_ACCEL 0x0E
rctaduio 0:80a695ae3cc3 64 #define SELF_TEST_Z_ACCEL 0x0F
rctaduio 0:80a695ae3cc3 65
rctaduio 0:80a695ae3cc3 66 #define SELF_TEST_A 0x10
rctaduio 0:80a695ae3cc3 67
rctaduio 0:80a695ae3cc3 68 #define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope
rctaduio 0:80a695ae3cc3 69 #define XG_OFFSET_L 0x14
rctaduio 0:80a695ae3cc3 70 #define YG_OFFSET_H 0x15
rctaduio 0:80a695ae3cc3 71 #define YG_OFFSET_L 0x16
rctaduio 0:80a695ae3cc3 72 #define ZG_OFFSET_H 0x17
rctaduio 0:80a695ae3cc3 73 #define ZG_OFFSET_L 0x18
rctaduio 0:80a695ae3cc3 74 #define SMPLRT_DIV 0x19
rctaduio 0:80a695ae3cc3 75 #define CONFIG 0x1A
rctaduio 0:80a695ae3cc3 76 #define GYRO_CONFIG 0x1B
rctaduio 0:80a695ae3cc3 77 #define ACCEL_CONFIG 0x1C
rctaduio 0:80a695ae3cc3 78 #define ACCEL_CONFIG2 0x1D
rctaduio 0:80a695ae3cc3 79 #define LP_ACCEL_ODR 0x1E
rctaduio 0:80a695ae3cc3 80 #define WOM_THR 0x1F
rctaduio 0:80a695ae3cc3 81
rctaduio 0:80a695ae3cc3 82 #define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms
rctaduio 0:80a695ae3cc3 83 #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]
rctaduio 0:80a695ae3cc3 84 #define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms
rctaduio 0:80a695ae3cc3 85
rctaduio 0:80a695ae3cc3 86 #define FIFO_EN 0x23
rctaduio 0:80a695ae3cc3 87 #define I2C_MST_CTRL 0x24
rctaduio 0:80a695ae3cc3 88 #define I2C_SLV0_ADDR 0x25
rctaduio 0:80a695ae3cc3 89 #define I2C_SLV0_REG 0x26
rctaduio 0:80a695ae3cc3 90 #define I2C_SLV0_CTRL 0x27
rctaduio 0:80a695ae3cc3 91 #define I2C_SLV1_ADDR 0x28
rctaduio 0:80a695ae3cc3 92 #define I2C_SLV1_REG 0x29
rctaduio 0:80a695ae3cc3 93 #define I2C_SLV1_CTRL 0x2A
rctaduio 0:80a695ae3cc3 94 #define I2C_SLV2_ADDR 0x2B
rctaduio 0:80a695ae3cc3 95 #define I2C_SLV2_REG 0x2C
rctaduio 0:80a695ae3cc3 96 #define I2C_SLV2_CTRL 0x2D
rctaduio 0:80a695ae3cc3 97 #define I2C_SLV3_ADDR 0x2E
rctaduio 0:80a695ae3cc3 98 #define I2C_SLV3_REG 0x2F
rctaduio 0:80a695ae3cc3 99 #define I2C_SLV3_CTRL 0x30
rctaduio 0:80a695ae3cc3 100 #define I2C_SLV4_ADDR 0x31
rctaduio 0:80a695ae3cc3 101 #define I2C_SLV4_REG 0x32
rctaduio 0:80a695ae3cc3 102 #define I2C_SLV4_DO 0x33
rctaduio 0:80a695ae3cc3 103 #define I2C_SLV4_CTRL 0x34
rctaduio 0:80a695ae3cc3 104 #define I2C_SLV4_DI 0x35
rctaduio 0:80a695ae3cc3 105 #define I2C_MST_STATUS 0x36
rctaduio 0:80a695ae3cc3 106 #define INT_PIN_CFG 0x37
rctaduio 0:80a695ae3cc3 107 #define INT_ENABLE 0x38
rctaduio 0:80a695ae3cc3 108 #define DMP_INT_STATUS 0x39 // Check DMP interrupt
rctaduio 0:80a695ae3cc3 109 #define INT_STATUS 0x3A
rctaduio 0:80a695ae3cc3 110 #define ACCEL_XOUT_H 0x3B
rctaduio 0:80a695ae3cc3 111 #define ACCEL_XOUT_L 0x3C
rctaduio 0:80a695ae3cc3 112 #define ACCEL_YOUT_H 0x3D
rctaduio 0:80a695ae3cc3 113 #define ACCEL_YOUT_L 0x3E
rctaduio 0:80a695ae3cc3 114 #define ACCEL_ZOUT_H 0x3F
rctaduio 0:80a695ae3cc3 115 #define ACCEL_ZOUT_L 0x40
rctaduio 0:80a695ae3cc3 116 #define TEMP_OUT_H 0x41
rctaduio 0:80a695ae3cc3 117 #define TEMP_OUT_L 0x42
rctaduio 0:80a695ae3cc3 118 #define GYRO_XOUT_H 0x43
rctaduio 0:80a695ae3cc3 119 #define GYRO_XOUT_L 0x44
rctaduio 0:80a695ae3cc3 120 #define GYRO_YOUT_H 0x45
rctaduio 0:80a695ae3cc3 121 #define GYRO_YOUT_L 0x46
rctaduio 0:80a695ae3cc3 122 #define GYRO_ZOUT_H 0x47
rctaduio 0:80a695ae3cc3 123 #define GYRO_ZOUT_L 0x48
rctaduio 0:80a695ae3cc3 124 #define EXT_SENS_DATA_00 0x49
rctaduio 0:80a695ae3cc3 125 #define EXT_SENS_DATA_01 0x4A
rctaduio 0:80a695ae3cc3 126 #define EXT_SENS_DATA_02 0x4B
rctaduio 0:80a695ae3cc3 127 #define EXT_SENS_DATA_03 0x4C
rctaduio 0:80a695ae3cc3 128 #define EXT_SENS_DATA_04 0x4D
rctaduio 0:80a695ae3cc3 129 #define EXT_SENS_DATA_05 0x4E
rctaduio 0:80a695ae3cc3 130 #define EXT_SENS_DATA_06 0x4F
rctaduio 0:80a695ae3cc3 131 #define EXT_SENS_DATA_07 0x50
rctaduio 0:80a695ae3cc3 132 #define EXT_SENS_DATA_08 0x51
rctaduio 0:80a695ae3cc3 133 #define EXT_SENS_DATA_09 0x52
rctaduio 0:80a695ae3cc3 134 #define EXT_SENS_DATA_10 0x53
rctaduio 0:80a695ae3cc3 135 #define EXT_SENS_DATA_11 0x54
rctaduio 0:80a695ae3cc3 136 #define EXT_SENS_DATA_12 0x55
rctaduio 0:80a695ae3cc3 137 #define EXT_SENS_DATA_13 0x56
rctaduio 0:80a695ae3cc3 138 #define EXT_SENS_DATA_14 0x57
rctaduio 0:80a695ae3cc3 139 #define EXT_SENS_DATA_15 0x58
rctaduio 0:80a695ae3cc3 140 #define EXT_SENS_DATA_16 0x59
rctaduio 0:80a695ae3cc3 141 #define EXT_SENS_DATA_17 0x5A
rctaduio 0:80a695ae3cc3 142 #define EXT_SENS_DATA_18 0x5B
rctaduio 0:80a695ae3cc3 143 #define EXT_SENS_DATA_19 0x5C
rctaduio 0:80a695ae3cc3 144 #define EXT_SENS_DATA_20 0x5D
rctaduio 0:80a695ae3cc3 145 #define EXT_SENS_DATA_21 0x5E
rctaduio 0:80a695ae3cc3 146 #define EXT_SENS_DATA_22 0x5F
rctaduio 0:80a695ae3cc3 147 #define EXT_SENS_DATA_23 0x60
rctaduio 0:80a695ae3cc3 148 #define MOT_DETECT_STATUS 0x61
rctaduio 0:80a695ae3cc3 149 #define I2C_SLV0_DO 0x63
rctaduio 0:80a695ae3cc3 150 #define I2C_SLV1_DO 0x64
rctaduio 0:80a695ae3cc3 151 #define I2C_SLV2_DO 0x65
rctaduio 0:80a695ae3cc3 152 #define I2C_SLV3_DO 0x66
rctaduio 0:80a695ae3cc3 153 #define I2C_MST_DELAY_CTRL 0x67
rctaduio 0:80a695ae3cc3 154 #define SIGNAL_PATH_RESET 0x68
rctaduio 0:80a695ae3cc3 155 #define MOT_DETECT_CTRL 0x69
rctaduio 0:80a695ae3cc3 156 #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP
rctaduio 0:80a695ae3cc3 157 #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode
rctaduio 0:80a695ae3cc3 158 #define PWR_MGMT_2 0x6C
rctaduio 0:80a695ae3cc3 159 #define DMP_BANK 0x6D // Activates a specific bank in the DMP
rctaduio 0:80a695ae3cc3 160 #define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank
rctaduio 0:80a695ae3cc3 161 #define DMP_REG 0x6F // Register in DMP from which to read or to which to write
rctaduio 0:80a695ae3cc3 162 #define DMP_REG_1 0x70
rctaduio 0:80a695ae3cc3 163 #define DMP_REG_2 0x71
rctaduio 0:80a695ae3cc3 164 #define FIFO_COUNTH 0x72
rctaduio 0:80a695ae3cc3 165 #define FIFO_COUNTL 0x73
rctaduio 0:80a695ae3cc3 166 #define FIFO_R_W 0x74
rctaduio 0:80a695ae3cc3 167 #define WHO_AM_I_MPU9250 0x75 // Should return 0x71
rctaduio 0:80a695ae3cc3 168 #define XA_OFFSET_H 0x77
rctaduio 0:80a695ae3cc3 169 #define XA_OFFSET_L 0x78
rctaduio 0:80a695ae3cc3 170 #define YA_OFFSET_H 0x7A
rctaduio 0:80a695ae3cc3 171 #define YA_OFFSET_L 0x7B
rctaduio 0:80a695ae3cc3 172 #define ZA_OFFSET_H 0x7D
rctaduio 0:80a695ae3cc3 173 #define ZA_OFFSET_L 0x7E
rctaduio 0:80a695ae3cc3 174
rctaduio 0:80a695ae3cc3 175 // Using the MSENSR-9250 breakout board, ADO is set to 0
rctaduio 0:80a695ae3cc3 176 // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1
rctaduio 0:80a695ae3cc3 177 //mbed uses the eight-bit device address, so shift seven-bit addresses left by one!
rctaduio 0:80a695ae3cc3 178 #define ADO 0
rctaduio 0:80a695ae3cc3 179 #if ADO
rctaduio 0:80a695ae3cc3 180 #define MPU9250_ADDRESS 0x69<<1 // Device address when ADO = 1
rctaduio 0:80a695ae3cc3 181 #else
rctaduio 0:80a695ae3cc3 182 #define MPU9250_ADDRESS 0x68<<1 // Device address when ADO = 0
rctaduio 0:80a695ae3cc3 183 #endif
rctaduio 0:80a695ae3cc3 184
rctaduio 0:80a695ae3cc3 185 // Set initial input parameters
rctaduio 0:80a695ae3cc3 186 enum Ascale {
rctaduio 0:80a695ae3cc3 187 AFS_2G = 0,
rctaduio 0:80a695ae3cc3 188 AFS_4G,
rctaduio 0:80a695ae3cc3 189 AFS_8G,
rctaduio 0:80a695ae3cc3 190 AFS_16G
rctaduio 0:80a695ae3cc3 191 };
rctaduio 0:80a695ae3cc3 192
rctaduio 0:80a695ae3cc3 193 enum Gscale {
rctaduio 0:80a695ae3cc3 194 GFS_250DPS = 0,
rctaduio 0:80a695ae3cc3 195 GFS_500DPS,
rctaduio 0:80a695ae3cc3 196 GFS_1000DPS,
rctaduio 0:80a695ae3cc3 197 GFS_2000DPS
rctaduio 0:80a695ae3cc3 198 };
rctaduio 0:80a695ae3cc3 199
rctaduio 0:80a695ae3cc3 200 enum Mscale {
rctaduio 0:80a695ae3cc3 201 MFS_14BITS = 0, // 0.6 mG per LSB
rctaduio 0:80a695ae3cc3 202 MFS_16BITS // 0.15 mG per LSB
rctaduio 0:80a695ae3cc3 203 };
rctaduio 0:80a695ae3cc3 204
rctaduio 0:80a695ae3cc3 205 uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G
rctaduio 0:80a695ae3cc3 206 uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS
rctaduio 0:80a695ae3cc3 207 uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution
rctaduio 0:80a695ae3cc3 208 uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR
rctaduio 0:80a695ae3cc3 209 float aRes, gRes, mRes; // scale resolutions per LSB for the sensors
rctaduio 0:80a695ae3cc3 210
rctaduio 0:80a695ae3cc3 211 //Set up I2C, (SDA,SCL)
rctaduio 0:80a695ae3cc3 212 I2C i2c(I2C_SDA, I2C_SCL);
rctaduio 0:80a695ae3cc3 213
rctaduio 0:80a695ae3cc3 214 DigitalOut myled(LED1);
rctaduio 0:80a695ae3cc3 215
rctaduio 0:80a695ae3cc3 216 // Pin definitions
rctaduio 0:80a695ae3cc3 217 int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins
rctaduio 0:80a695ae3cc3 218
rctaduio 0:80a695ae3cc3 219 float SelfTest[6];
rctaduio 0:80a695ae3cc3 220
rctaduio 0:80a695ae3cc3 221 int delt_t = 0; // used to control display output rate
rctaduio 0:80a695ae3cc3 222 int count = 0; // used to control display output rate
rctaduio 0:80a695ae3cc3 223
rctaduio 0:80a695ae3cc3 224 // parameters for 6 DoF sensor fusion calculations
rctaduio 0:80a695ae3cc3 225 float PI = 3.14159265358979323846f;
rctaduio 0:80a695ae3cc3 226 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
rctaduio 0:80a695ae3cc3 227 //float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
rctaduio 0:80a695ae3cc3 228 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
rctaduio 0:80a695ae3cc3 229 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
rctaduio 0:80a695ae3cc3 230 #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
rctaduio 0:80a695ae3cc3 231 #define Ki 0.0f
rctaduio 0:80a695ae3cc3 232
rctaduio 0:80a695ae3cc3 233
rctaduio 0:80a695ae3cc3 234
rctaduio 0:80a695ae3cc3 235 class MPU9250
rctaduio 0:80a695ae3cc3 236 {
rctaduio 0:80a695ae3cc3 237
rctaduio 0:80a695ae3cc3 238 protected:
rctaduio 0:80a695ae3cc3 239
rctaduio 0:80a695ae3cc3 240 public:
rctaduio 0:80a695ae3cc3 241 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
rctaduio 0:80a695ae3cc3 242 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
rctaduio 0:80a695ae3cc3 243 int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output
rctaduio 0:80a695ae3cc3 244 float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
rctaduio 0:80a695ae3cc3 245 float magCalibration[3];
rctaduio 0:80a695ae3cc3 246 float magbias[3]; // Factory mag calibration and mag bias
rctaduio 0:80a695ae3cc3 247 float gyroBias[3];
rctaduio 0:80a695ae3cc3 248 float accelBias[3]; // Bias corrections for gyro and accelerometer
rctaduio 0:80a695ae3cc3 249 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
rctaduio 0:80a695ae3cc3 250 float temperature;
rctaduio 0:80a695ae3cc3 251 float pitch, yaw, roll;
rctaduio 0:80a695ae3cc3 252 float deltat; // integration interval for both filter schemes
rctaduio 0:80a695ae3cc3 253 int lastUpdate;
rctaduio 0:80a695ae3cc3 254 int firstUpdate;
rctaduio 0:80a695ae3cc3 255 int Now; // used to calculate integration interval
rctaduio 0:80a695ae3cc3 256 float q[4]; // vector to hold quaternion
rctaduio 0:80a695ae3cc3 257 float eInt[3]; // vector to hold integral error for Mahony method
rctaduio 0:80a695ae3cc3 258 uint32_t checksum;
rctaduio 0:80a695ae3cc3 259
rctaduio 0:80a695ae3cc3 260 MPU9250() {
rctaduio 0:80a695ae3cc3 261 ax=ay=az=gx=gy=gz=mx=my=mz=0.0;
rctaduio 0:80a695ae3cc3 262 for (int i = 0; i < 3; i++) {
rctaduio 0:80a695ae3cc3 263 magCalibration[i] = 0.0;
rctaduio 0:80a695ae3cc3 264 magbias[i] = 0.0;
rctaduio 0:80a695ae3cc3 265 gyroBias[i] = 0.0;
rctaduio 0:80a695ae3cc3 266 accelBias[i] = 0.0;
rctaduio 0:80a695ae3cc3 267 eInt[i] = 0.0f;
rctaduio 0:80a695ae3cc3 268 } // end of for
rctaduio 0:80a695ae3cc3 269 q[0] = 1.0f;
rctaduio 0:80a695ae3cc3 270 q[1] = 0.0f;
rctaduio 0:80a695ae3cc3 271 q[2] = 0.0f;
rctaduio 0:80a695ae3cc3 272 q[3] = 0.0f;
rctaduio 0:80a695ae3cc3 273 lastUpdate = 0, firstUpdate = 0, Now = 0;
rctaduio 0:80a695ae3cc3 274 deltat = 0.0f;
rctaduio 0:80a695ae3cc3 275 } // end of initalizer
rctaduio 0:80a695ae3cc3 276
rctaduio 0:80a695ae3cc3 277 //===================================================================================================================
rctaduio 0:80a695ae3cc3 278 //====== Set of useful function to access acceleratio, gyroscope, and temperature data
rctaduio 0:80a695ae3cc3 279 //===================================================================================================================
rctaduio 0:80a695ae3cc3 280
rctaduio 0:80a695ae3cc3 281 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data) {
rctaduio 0:80a695ae3cc3 282 char data_write[2];
rctaduio 0:80a695ae3cc3 283 data_write[0] = subAddress;
rctaduio 0:80a695ae3cc3 284 data_write[1] = data;
rctaduio 0:80a695ae3cc3 285 i2c.write(address, data_write, 2, 0);
rctaduio 0:80a695ae3cc3 286 }
rctaduio 0:80a695ae3cc3 287
rctaduio 0:80a695ae3cc3 288
rctaduio 0:80a695ae3cc3 289 void selfTest(Serial &pc , bool show = false) {
rctaduio 0:80a695ae3cc3 290 resetMPU9250(); // Reset registers to default in preparation for device calibration
rctaduio 0:80a695ae3cc3 291 MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values
rctaduio 0:80a695ae3cc3 292 if (show) {
rctaduio 0:80a695ae3cc3 293 pc.printf("x-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[0]);
rctaduio 0:80a695ae3cc3 294 pc.printf("y-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[1]);
rctaduio 0:80a695ae3cc3 295 pc.printf("z-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[2]);
rctaduio 0:80a695ae3cc3 296 pc.printf("x-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[3]);
rctaduio 0:80a695ae3cc3 297 pc.printf("y-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[4]);
rctaduio 0:80a695ae3cc3 298 pc.printf("z-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[5]);
rctaduio 0:80a695ae3cc3 299 }
rctaduio 0:80a695ae3cc3 300 //calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers
rctaduio 0:80a695ae3cc3 301 if(show) {
rctaduio 0:80a695ae3cc3 302 pc.printf("x gyro bias = %f\n\r", gyroBias[0]);
rctaduio 0:80a695ae3cc3 303 pc.printf("y gyro bias = %f\n\r", gyroBias[1]);
rctaduio 0:80a695ae3cc3 304 pc.printf("z gyro bias = %f\n\r", gyroBias[2]);
rctaduio 0:80a695ae3cc3 305 pc.printf("x accel bias = %f\n\r", accelBias[0]);
rctaduio 0:80a695ae3cc3 306 pc.printf("y accel bias = %f\n\r", accelBias[1]);
rctaduio 0:80a695ae3cc3 307 pc.printf("z accel bias = %f\n\r", accelBias[2]);
rctaduio 0:80a695ae3cc3 308 }
rctaduio 0:80a695ae3cc3 309 }
rctaduio 0:80a695ae3cc3 310
rctaduio 0:80a695ae3cc3 311
rctaduio 0:80a695ae3cc3 312 void config(Serial &pc, bool show = false) {
rctaduio 0:80a695ae3cc3 313 initMPU9250();
rctaduio 0:80a695ae3cc3 314 if (show)
rctaduio 0:80a695ae3cc3 315 pc.printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
rctaduio 0:80a695ae3cc3 316 initAK8963(magCalibration);
rctaduio 0:80a695ae3cc3 317 if(show) {
rctaduio 0:80a695ae3cc3 318 pc.printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer
rctaduio 0:80a695ae3cc3 319 pc.printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale));
rctaduio 0:80a695ae3cc3 320 pc.printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale));
rctaduio 0:80a695ae3cc3 321 if(Mscale == 0) pc.printf("Magnetometer resolution = 14 bits\n\r");
rctaduio 0:80a695ae3cc3 322 if(Mscale == 1) pc.printf("Magnetometer resolution = 16 bits\n\r");
rctaduio 0:80a695ae3cc3 323 if(Mmode == 2) pc.printf("Magnetometer ODR = 8 Hz\n\r");
rctaduio 0:80a695ae3cc3 324 if(Mmode == 6) pc.printf("Magnetometer ODR = 100 Hz\n\r");
rctaduio 0:80a695ae3cc3 325 pc.printf("mag calibration: \r\nx:\t%f\r\ny:\t%f\r\nz:\t%f\r\n", magbias[0], magbias[1], magbias[2]);
rctaduio 0:80a695ae3cc3 326 }
rctaduio 0:80a695ae3cc3 327 }
rctaduio 0:80a695ae3cc3 328
rctaduio 0:80a695ae3cc3 329
rctaduio 0:80a695ae3cc3 330 void sensitivity(Serial &pc, bool show = false) {
rctaduio 0:80a695ae3cc3 331 getAres(); // Get accelerometer sensitivity
rctaduio 0:80a695ae3cc3 332 getGres(); // Get gyro sensitivity
rctaduio 0:80a695ae3cc3 333 getMres(); // Get magnetometer sensitivity
rctaduio 0:80a695ae3cc3 334 if (show) {
rctaduio 0:80a695ae3cc3 335 pc.printf("Accelerometer sensitivity is %f LSB/g \n\r", 1.0f/aRes);
rctaduio 0:80a695ae3cc3 336 pc.printf("Gyroscope sensitivity is %f LSB/deg/s \n\r", 1.0f/gRes);
rctaduio 0:80a695ae3cc3 337 pc.printf("Magnetometer sensitivity is %f LSB/G \n\r", 1.0f/mRes);
rctaduio 0:80a695ae3cc3 338 }
rctaduio 0:80a695ae3cc3 339 }
rctaduio 0:80a695ae3cc3 340
rctaduio 0:80a695ae3cc3 341
rctaduio 0:80a695ae3cc3 342 char readByte(uint8_t address, uint8_t subAddress) {
rctaduio 0:80a695ae3cc3 343 char data[1]; // `data` will store the register data
rctaduio 0:80a695ae3cc3 344 char data_write[1];
rctaduio 0:80a695ae3cc3 345 data_write[0] = subAddress;
rctaduio 0:80a695ae3cc3 346 i2c.write(address, data_write, 1, 1); // no stop
rctaduio 0:80a695ae3cc3 347 i2c.read(address, data, 1, 0);
rctaduio 0:80a695ae3cc3 348 return data[0];
rctaduio 0:80a695ae3cc3 349 }
rctaduio 0:80a695ae3cc3 350
rctaduio 0:80a695ae3cc3 351
rctaduio 0:80a695ae3cc3 352 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) {
rctaduio 0:80a695ae3cc3 353 char data[14];
rctaduio 0:80a695ae3cc3 354 char data_write[1];
rctaduio 0:80a695ae3cc3 355 data_write[0] = subAddress;
rctaduio 0:80a695ae3cc3 356 i2c.write(address, data_write, 1, 1); // no stop
rctaduio 0:80a695ae3cc3 357 i2c.read(address, data, count, 0);
rctaduio 0:80a695ae3cc3 358 for(int ii = 0; ii < count; ii++) {
rctaduio 0:80a695ae3cc3 359 dest[ii] = data[ii];
rctaduio 0:80a695ae3cc3 360 }
rctaduio 0:80a695ae3cc3 361 }
rctaduio 0:80a695ae3cc3 362
rctaduio 0:80a695ae3cc3 363
rctaduio 0:80a695ae3cc3 364 void getMres() {
rctaduio 0:80a695ae3cc3 365 switch (Mscale) {
rctaduio 0:80a695ae3cc3 366 // Possible magnetometer scales (and their register bit settings) are:
rctaduio 0:80a695ae3cc3 367 // 14 bit resolution (0) and 16 bit resolution (1)
rctaduio 0:80a695ae3cc3 368 case MFS_14BITS:
rctaduio 0:80a695ae3cc3 369 mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss
rctaduio 0:80a695ae3cc3 370 break;
rctaduio 0:80a695ae3cc3 371 case MFS_16BITS:
rctaduio 0:80a695ae3cc3 372 mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss
rctaduio 0:80a695ae3cc3 373 break;
rctaduio 0:80a695ae3cc3 374 }
rctaduio 0:80a695ae3cc3 375 }
rctaduio 0:80a695ae3cc3 376
rctaduio 0:80a695ae3cc3 377
rctaduio 0:80a695ae3cc3 378 void getGres() {
rctaduio 0:80a695ae3cc3 379 switch (Gscale) {
rctaduio 0:80a695ae3cc3 380 // Possible gyro scales (and their register bit settings) are:
rctaduio 0:80a695ae3cc3 381 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
rctaduio 0:80a695ae3cc3 382 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
rctaduio 0:80a695ae3cc3 383 case GFS_250DPS:
rctaduio 0:80a695ae3cc3 384 gRes = 250.0/32768.0;
rctaduio 0:80a695ae3cc3 385 break;
rctaduio 0:80a695ae3cc3 386 case GFS_500DPS:
rctaduio 0:80a695ae3cc3 387 gRes = 500.0/32768.0;
rctaduio 0:80a695ae3cc3 388 break;
rctaduio 0:80a695ae3cc3 389 case GFS_1000DPS:
rctaduio 0:80a695ae3cc3 390 gRes = 1000.0/32768.0;
rctaduio 0:80a695ae3cc3 391 break;
rctaduio 0:80a695ae3cc3 392 case GFS_2000DPS:
rctaduio 0:80a695ae3cc3 393 gRes = 2000.0/32768.0;
rctaduio 0:80a695ae3cc3 394 break;
rctaduio 0:80a695ae3cc3 395 }
rctaduio 0:80a695ae3cc3 396 }
rctaduio 0:80a695ae3cc3 397
rctaduio 0:80a695ae3cc3 398
rctaduio 0:80a695ae3cc3 399 void getAres() {
rctaduio 0:80a695ae3cc3 400 switch (Ascale) {
rctaduio 0:80a695ae3cc3 401 // Possible accelerometer scales (and their register bit settings) are:
rctaduio 0:80a695ae3cc3 402 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
rctaduio 0:80a695ae3cc3 403 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
rctaduio 0:80a695ae3cc3 404 case AFS_2G:
rctaduio 0:80a695ae3cc3 405 aRes = 2.0/32768.0;
rctaduio 0:80a695ae3cc3 406 break;
rctaduio 0:80a695ae3cc3 407 case AFS_4G:
rctaduio 0:80a695ae3cc3 408 aRes = 4.0/32768.0;
rctaduio 0:80a695ae3cc3 409 break;
rctaduio 0:80a695ae3cc3 410 case AFS_8G:
rctaduio 0:80a695ae3cc3 411 aRes = 8.0/32768.0;
rctaduio 0:80a695ae3cc3 412 break;
rctaduio 0:80a695ae3cc3 413 case AFS_16G:
rctaduio 0:80a695ae3cc3 414 aRes = 16.0/32768.0;
rctaduio 0:80a695ae3cc3 415 break;
rctaduio 0:80a695ae3cc3 416 }
rctaduio 0:80a695ae3cc3 417 }
rctaduio 0:80a695ae3cc3 418
rctaduio 0:80a695ae3cc3 419
rctaduio 0:80a695ae3cc3 420 void readAccelData() {
rctaduio 0:80a695ae3cc3 421 uint8_t rawData[6]; // x/y/z accel register data stored here
rctaduio 0:80a695ae3cc3 422 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
rctaduio 0:80a695ae3cc3 423 ax = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
rctaduio 0:80a695ae3cc3 424 ay = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
rctaduio 0:80a695ae3cc3 425 az = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
rctaduio 0:80a695ae3cc3 426 }
rctaduio 0:80a695ae3cc3 427
rctaduio 0:80a695ae3cc3 428 void readGyroData() {
rctaduio 0:80a695ae3cc3 429 uint8_t rawData[6]; // x/y/z gyro register data stored here
rctaduio 0:80a695ae3cc3 430 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]) ; // Read the six raw data registers sequentially into data array
rctaduio 0:80a695ae3cc3 431 gx = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
rctaduio 0:80a695ae3cc3 432 gy = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
rctaduio 0:80a695ae3cc3 433 gz = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
rctaduio 0:80a695ae3cc3 434 }
rctaduio 0:80a695ae3cc3 435
rctaduio 0:80a695ae3cc3 436 void readMagData() {
rctaduio 0:80a695ae3cc3 437 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
rctaduio 0:80a695ae3cc3 438 if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) {
rctaduio 0:80a695ae3cc3 439 // wait for magnetometer data ready bit to be set
rctaduio 0:80a695ae3cc3 440 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
rctaduio 0:80a695ae3cc3 441 uint8_t c = rawData[6]; // End data read by reading ST2 register
rctaduio 0:80a695ae3cc3 442 if(!(c & 0x08)) {
rctaduio 0:80a695ae3cc3 443 // Check if magnetic sensor overflow set, if not then report data
rctaduio 0:80a695ae3cc3 444 mx = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]) ; // Turn the MSB and LSB into a signed 16-bit value
rctaduio 0:80a695ae3cc3 445 my = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian
rctaduio 0:80a695ae3cc3 446 mz = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ;
rctaduio 0:80a695ae3cc3 447 }
rctaduio 0:80a695ae3cc3 448 }
rctaduio 0:80a695ae3cc3 449 }
rctaduio 0:80a695ae3cc3 450
rctaduio 0:80a695ae3cc3 451 void readimu() {
rctaduio 0:80a695ae3cc3 452 readAccelData();
rctaduio 0:80a695ae3cc3 453 ax = ax*aRes - accelBias[0];
rctaduio 0:80a695ae3cc3 454 ay = ay*aRes - accelBias[1];
rctaduio 0:80a695ae3cc3 455 az = az*aRes - accelBias[2];
rctaduio 0:80a695ae3cc3 456
rctaduio 0:80a695ae3cc3 457 readGyroData();
rctaduio 0:80a695ae3cc3 458 gx = gx*gRes - gyroBias[0];
rctaduio 0:80a695ae3cc3 459 gy = gy*gRes - gyroBias[1];
rctaduio 0:80a695ae3cc3 460 gz = gz*gRes - gyroBias[2];
rctaduio 0:80a695ae3cc3 461
rctaduio 0:80a695ae3cc3 462 // Calculate the magnetometer values in milliGauss
rctaduio 0:80a695ae3cc3 463 // Include factory calibration per data sheet and user environmental corrections
rctaduio 0:80a695ae3cc3 464 readMagData();
rctaduio 0:80a695ae3cc3 465 mx = mx*mRes*magCalibration[0] - magbias[0];
rctaduio 0:80a695ae3cc3 466 my = my*mRes*magCalibration[1] - magbias[1];
rctaduio 0:80a695ae3cc3 467 mz = mz*mRes*magCalibration[2] - magbias[2];
rctaduio 0:80a695ae3cc3 468
rctaduio 0:80a695ae3cc3 469 checksum = 0;
rctaduio 0:80a695ae3cc3 470 checksum += int(1000*ax) + int(1000*ay) + int(1000*az) +int(gx) + int(gy) + int(gz) +int(mx) + int(my) + int(mz);
rctaduio 0:80a695ae3cc3 471
rctaduio 0:80a695ae3cc3 472 }// end of read IMUData()
rctaduio 0:80a695ae3cc3 473
rctaduio 0:80a695ae3cc3 474 int16_t readTempData() {
rctaduio 0:80a695ae3cc3 475 uint8_t rawData[2]; // x/y/z gyro register data stored here
rctaduio 0:80a695ae3cc3 476 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
rctaduio 0:80a695ae3cc3 477 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
rctaduio 0:80a695ae3cc3 478 }
rctaduio 0:80a695ae3cc3 479
rctaduio 0:80a695ae3cc3 480
rctaduio 0:80a695ae3cc3 481 void resetMPU9250() {
rctaduio 0:80a695ae3cc3 482 // reset device
rctaduio 0:80a695ae3cc3 483 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
rctaduio 0:80a695ae3cc3 484 wait(0.1);
rctaduio 0:80a695ae3cc3 485 }
rctaduio 0:80a695ae3cc3 486
rctaduio 0:80a695ae3cc3 487 void initAK8963(float * destination) {
rctaduio 0:80a695ae3cc3 488 // First extract the factory calibration for each magnetometer axis
rctaduio 0:80a695ae3cc3 489 uint8_t rawData[3]; // x/y/z gyro calibration data stored here
rctaduio 0:80a695ae3cc3 490 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
rctaduio 0:80a695ae3cc3 491 wait(0.01);
rctaduio 0:80a695ae3cc3 492 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
rctaduio 0:80a695ae3cc3 493 wait(0.01);
rctaduio 0:80a695ae3cc3 494 readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
rctaduio 0:80a695ae3cc3 495 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
rctaduio 0:80a695ae3cc3 496 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
rctaduio 0:80a695ae3cc3 497 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
rctaduio 0:80a695ae3cc3 498 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
rctaduio 0:80a695ae3cc3 499 wait(0.01);
rctaduio 0:80a695ae3cc3 500 // Configure the magnetometer for continuous read and highest resolution
rctaduio 0:80a695ae3cc3 501 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
rctaduio 0:80a695ae3cc3 502 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
rctaduio 0:80a695ae3cc3 503 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
rctaduio 0:80a695ae3cc3 504 wait(0.01);
rctaduio 0:80a695ae3cc3 505 }
rctaduio 0:80a695ae3cc3 506
rctaduio 0:80a695ae3cc3 507
rctaduio 0:80a695ae3cc3 508 void initMPU9250() {
rctaduio 0:80a695ae3cc3 509 // Initialize MPU9250 device
rctaduio 0:80a695ae3cc3 510 // wake up device
rctaduio 0:80a695ae3cc3 511 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
rctaduio 0:80a695ae3cc3 512 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
rctaduio 0:80a695ae3cc3 513
rctaduio 0:80a695ae3cc3 514 // get stable time source
rctaduio 0:80a695ae3cc3 515 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
rctaduio 0:80a695ae3cc3 516
rctaduio 0:80a695ae3cc3 517 // Configure Gyro and Accelerometer
rctaduio 0:80a695ae3cc3 518 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
rctaduio 0:80a695ae3cc3 519 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
rctaduio 0:80a695ae3cc3 520 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
rctaduio 0:80a695ae3cc3 521 writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
rctaduio 0:80a695ae3cc3 522
rctaduio 0:80a695ae3cc3 523 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
rctaduio 0:80a695ae3cc3 524 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
rctaduio 0:80a695ae3cc3 525
rctaduio 0:80a695ae3cc3 526 // Set gyroscope full scale range
rctaduio 0:80a695ae3cc3 527 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
rctaduio 0:80a695ae3cc3 528 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
rctaduio 0:80a695ae3cc3 529 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
rctaduio 0:80a695ae3cc3 530 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
rctaduio 0:80a695ae3cc3 531 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
rctaduio 0:80a695ae3cc3 532
rctaduio 0:80a695ae3cc3 533 // Set accelerometer configuration
rctaduio 0:80a695ae3cc3 534 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
rctaduio 0:80a695ae3cc3 535 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
rctaduio 0:80a695ae3cc3 536 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
rctaduio 0:80a695ae3cc3 537 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
rctaduio 0:80a695ae3cc3 538
rctaduio 0:80a695ae3cc3 539 // Set accelerometer sample rate configuration
rctaduio 0:80a695ae3cc3 540 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
rctaduio 0:80a695ae3cc3 541 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
rctaduio 0:80a695ae3cc3 542 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
rctaduio 0:80a695ae3cc3 543 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
rctaduio 0:80a695ae3cc3 544 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
rctaduio 0:80a695ae3cc3 545
rctaduio 0:80a695ae3cc3 546 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
rctaduio 0:80a695ae3cc3 547 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
rctaduio 0:80a695ae3cc3 548
rctaduio 0:80a695ae3cc3 549 // Configure Interrupts and Bypass Enable
rctaduio 0:80a695ae3cc3 550 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
rctaduio 0:80a695ae3cc3 551 // can join the I2C bus and all can be controlled by the Arduino as master
rctaduio 0:80a695ae3cc3 552 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
rctaduio 0:80a695ae3cc3 553 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
rctaduio 0:80a695ae3cc3 554 }
rctaduio 0:80a695ae3cc3 555
rctaduio 0:80a695ae3cc3 556 //void calibrateMag(float * dest1, float * dest2, Serial &pc)
rctaduio 0:80a695ae3cc3 557 void calibrateMag(Serial &pc) {
rctaduio 0:80a695ae3cc3 558 uint16_t ii = 0, sample_count = 0;
rctaduio 0:80a695ae3cc3 559 //int32_t mag_bias[3] = {0, 0, 0};
rctaduio 0:80a695ae3cc3 560 int32_t mag_scale[3] = {0, 0, 0};
rctaduio 0:80a695ae3cc3 561 int16_t mag_max[3] = {0x8000, 0x8000, 0x8000};
rctaduio 0:80a695ae3cc3 562 int16_t mag_min[3] = {0x7FFF, 0x7FFF, 0x7FFF};
rctaduio 0:80a695ae3cc3 563 int16_t mag_temp[3] = {0, 0, 0};
rctaduio 0:80a695ae3cc3 564 pc.printf("Pre-Mag Calibration: \r\nx:\t%f\r\ny:\t%f\r\nz:\t%f\r\n", magbias[0], magbias[1], magbias[2]);
rctaduio 0:80a695ae3cc3 565 pc.printf("Mag Calibration: Wave device in a figure eight until done!\n");
rctaduio 0:80a695ae3cc3 566 wait(4);
rctaduio 0:80a695ae3cc3 567
rctaduio 0:80a695ae3cc3 568 sample_count = 500;
rctaduio 0:80a695ae3cc3 569 for(ii = 0; ii < sample_count; ii++) {
rctaduio 0:80a695ae3cc3 570 //readMagData(mag_temp); // Read the mag data
rctaduio 0:80a695ae3cc3 571 for (int jj = 0; jj < 3; jj++) {
rctaduio 0:80a695ae3cc3 572 if(mag_temp[jj] > mag_max[jj]) mag_max[jj] = mag_temp[jj];
rctaduio 0:80a695ae3cc3 573 if(mag_temp[jj] < mag_min[jj]) mag_min[jj] = mag_temp[jj];
rctaduio 0:80a695ae3cc3 574 }// end of inner for
rctaduio 0:80a695ae3cc3 575 wait(.035); // at 8 Hz ODR, new mag data is available every 125 ms
rctaduio 0:80a695ae3cc3 576 pc.printf("%d\t%d\t%d\r\n", mag_temp[0], mag_temp[1], mag_temp[2]);
rctaduio 0:80a695ae3cc3 577 }// end of outer for
rctaduio 0:80a695ae3cc3 578 wait(1);
rctaduio 0:80a695ae3cc3 579 pc.printf("%d\t%d\t%d\t%d\t%d\t%d\r\n", mag_min[0], mag_max[0], mag_min[1], mag_max[1], mag_min[2], mag_max[2]);
rctaduio 0:80a695ae3cc3 580 wait(10);
rctaduio 0:80a695ae3cc3 581 // Get hard iron correction
rctaduio 0:80a695ae3cc3 582 magbias[0] = (mag_max[0] + mag_min[0])/2; // get average x mag bias in counts
rctaduio 0:80a695ae3cc3 583 magbias[1] = (mag_max[1] + mag_min[1])/2; // get average y mag bias in counts
rctaduio 0:80a695ae3cc3 584 magbias[2] = (mag_max[2] + mag_min[2])/2; // get average z mag bias in counts
rctaduio 0:80a695ae3cc3 585
rctaduio 0:80a695ae3cc3 586 //dest1[0] = (float) mag_bias[0]*mRes*MPU9250magCalibration[0]; // save mag biases in G for main program
rctaduio 0:80a695ae3cc3 587 //dest1[1] = (float) mag_bias[1]*mRes*MPU9250magCalibration[1];
rctaduio 0:80a695ae3cc3 588 //dest1[2] = (float) mag_bias[2]*mRes*MPU9250magCalibration[2];
rctaduio 0:80a695ae3cc3 589
rctaduio 0:80a695ae3cc3 590 // Get soft iron correction estimate
rctaduio 0:80a695ae3cc3 591 mag_scale[0] = (mag_max[0] - mag_min[0])/2; // get average x axis max chord length in counts
rctaduio 0:80a695ae3cc3 592 mag_scale[1] = (mag_max[1] - mag_min[1])/2; // get average y axis max chord length in counts
rctaduio 0:80a695ae3cc3 593 mag_scale[2] = (mag_max[2] - mag_min[2])/2; // get average z axis max chord length in counts
rctaduio 0:80a695ae3cc3 594
rctaduio 0:80a695ae3cc3 595 float avg_rad = mag_scale[0] + mag_scale[1] + mag_scale[2];
rctaduio 0:80a695ae3cc3 596 avg_rad /= 3.0;
rctaduio 0:80a695ae3cc3 597
rctaduio 0:80a695ae3cc3 598 //dest2[0] = avg_rad/((float)mag_scale[0]);
rctaduio 0:80a695ae3cc3 599 //dest2[1] = avg_rad/((float)mag_scale[1]);
rctaduio 0:80a695ae3cc3 600 //dest2[2] = avg_rad/((float)mag_scale[2]);
rctaduio 0:80a695ae3cc3 601 pc.printf("Post-Mag Calibration: \r\nx:\t%f\r\ny:\t%f\r\nz:\t%f\r\n", magbias[0], magbias[1], magbias[2]);
rctaduio 0:80a695ae3cc3 602 pc.printf("Mag Calibration done!\n");
rctaduio 0:80a695ae3cc3 603 }// end of calibrateMag
rctaduio 0:80a695ae3cc3 604
rctaduio 0:80a695ae3cc3 605 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
rctaduio 0:80a695ae3cc3 606 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
rctaduio 0:80a695ae3cc3 607 void calibrateMPU9250(float * dest1, float * dest2) {
rctaduio 0:80a695ae3cc3 608 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
rctaduio 0:80a695ae3cc3 609 uint16_t ii, packet_count, fifo_count;
rctaduio 0:80a695ae3cc3 610 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
rctaduio 0:80a695ae3cc3 611
rctaduio 0:80a695ae3cc3 612 // reset device, reset all registers, clear gyro and accelerometer bias registers
rctaduio 0:80a695ae3cc3 613 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
rctaduio 0:80a695ae3cc3 614 wait(0.1);
rctaduio 0:80a695ae3cc3 615
rctaduio 0:80a695ae3cc3 616 // get stable time source
rctaduio 0:80a695ae3cc3 617 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
rctaduio 0:80a695ae3cc3 618 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
rctaduio 0:80a695ae3cc3 619 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
rctaduio 0:80a695ae3cc3 620 wait(0.2);
rctaduio 0:80a695ae3cc3 621
rctaduio 0:80a695ae3cc3 622 // Configure device for bias calculation
rctaduio 0:80a695ae3cc3 623 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
rctaduio 0:80a695ae3cc3 624 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
rctaduio 0:80a695ae3cc3 625 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
rctaduio 0:80a695ae3cc3 626 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
rctaduio 0:80a695ae3cc3 627 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
rctaduio 0:80a695ae3cc3 628 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
rctaduio 0:80a695ae3cc3 629 wait(0.015);
rctaduio 0:80a695ae3cc3 630
rctaduio 0:80a695ae3cc3 631 // Configure MPU9250 gyro and accelerometer for bias calculation
rctaduio 0:80a695ae3cc3 632 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
rctaduio 0:80a695ae3cc3 633 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
rctaduio 0:80a695ae3cc3 634 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
rctaduio 0:80a695ae3cc3 635 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
rctaduio 0:80a695ae3cc3 636
rctaduio 0:80a695ae3cc3 637 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
rctaduio 0:80a695ae3cc3 638 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
rctaduio 0:80a695ae3cc3 639
rctaduio 0:80a695ae3cc3 640 // Configure FIFO to capture accelerometer and gyro data for bias calculation
rctaduio 0:80a695ae3cc3 641 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
rctaduio 0:80a695ae3cc3 642 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
rctaduio 0:80a695ae3cc3 643 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
rctaduio 0:80a695ae3cc3 644
rctaduio 0:80a695ae3cc3 645 // At end of sample accumulation, turn off FIFO sensor read
rctaduio 0:80a695ae3cc3 646 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
rctaduio 0:80a695ae3cc3 647 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
rctaduio 0:80a695ae3cc3 648 fifo_count = ((uint16_t)data[0] << 8) | data[1];
rctaduio 0:80a695ae3cc3 649 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
rctaduio 0:80a695ae3cc3 650
rctaduio 0:80a695ae3cc3 651 for (ii = 0; ii < packet_count; ii++) {
rctaduio 0:80a695ae3cc3 652 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
rctaduio 0:80a695ae3cc3 653 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
rctaduio 0:80a695ae3cc3 654 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
rctaduio 0:80a695ae3cc3 655 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
rctaduio 0:80a695ae3cc3 656 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
rctaduio 0:80a695ae3cc3 657 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
rctaduio 0:80a695ae3cc3 658 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
rctaduio 0:80a695ae3cc3 659 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
rctaduio 0:80a695ae3cc3 660
rctaduio 0:80a695ae3cc3 661 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
rctaduio 0:80a695ae3cc3 662 accel_bias[1] += (int32_t) accel_temp[1];
rctaduio 0:80a695ae3cc3 663 accel_bias[2] += (int32_t) accel_temp[2];
rctaduio 0:80a695ae3cc3 664 gyro_bias[0] += (int32_t) gyro_temp[0];
rctaduio 0:80a695ae3cc3 665 gyro_bias[1] += (int32_t) gyro_temp[1];
rctaduio 0:80a695ae3cc3 666 gyro_bias[2] += (int32_t) gyro_temp[2];
rctaduio 0:80a695ae3cc3 667
rctaduio 0:80a695ae3cc3 668 }
rctaduio 0:80a695ae3cc3 669 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
rctaduio 0:80a695ae3cc3 670 accel_bias[1] /= (int32_t) packet_count;
rctaduio 0:80a695ae3cc3 671 accel_bias[2] /= (int32_t) packet_count;
rctaduio 0:80a695ae3cc3 672 gyro_bias[0] /= (int32_t) packet_count;
rctaduio 0:80a695ae3cc3 673 gyro_bias[1] /= (int32_t) packet_count;
rctaduio 0:80a695ae3cc3 674 gyro_bias[2] /= (int32_t) packet_count;
rctaduio 0:80a695ae3cc3 675
rctaduio 0:80a695ae3cc3 676 if(accel_bias[2] > 0L) {
rctaduio 0:80a695ae3cc3 677 accel_bias[2] -= (int32_t) accelsensitivity; // Remove gravity from the z-axis accelerometer bias calculation
rctaduio 0:80a695ae3cc3 678 } else {
rctaduio 0:80a695ae3cc3 679 accel_bias[2] += (int32_t) accelsensitivity;
rctaduio 0:80a695ae3cc3 680 }
rctaduio 0:80a695ae3cc3 681
rctaduio 0:80a695ae3cc3 682 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
rctaduio 0:80a695ae3cc3 683 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
rctaduio 0:80a695ae3cc3 684 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
rctaduio 0:80a695ae3cc3 685 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
rctaduio 0:80a695ae3cc3 686 data[3] = (-gyro_bias[1]/4) & 0xFF;
rctaduio 0:80a695ae3cc3 687 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
rctaduio 0:80a695ae3cc3 688 data[5] = (-gyro_bias[2]/4) & 0xFF;
rctaduio 0:80a695ae3cc3 689
rctaduio 0:80a695ae3cc3 690 /// Push gyro biases to hardware registers
rctaduio 0:80a695ae3cc3 691 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
rctaduio 0:80a695ae3cc3 692 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
rctaduio 0:80a695ae3cc3 693 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
rctaduio 0:80a695ae3cc3 694 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
rctaduio 0:80a695ae3cc3 695 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
rctaduio 0:80a695ae3cc3 696 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);
rctaduio 0:80a695ae3cc3 697 */
rctaduio 0:80a695ae3cc3 698 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
rctaduio 0:80a695ae3cc3 699 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
rctaduio 0:80a695ae3cc3 700 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
rctaduio 0:80a695ae3cc3 701
rctaduio 0:80a695ae3cc3 702 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
rctaduio 0:80a695ae3cc3 703 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
rctaduio 0:80a695ae3cc3 704 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
rctaduio 0:80a695ae3cc3 705 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
rctaduio 0:80a695ae3cc3 706 // the accelerometer biases calculated above must be divided by 8.
rctaduio 0:80a695ae3cc3 707
rctaduio 0:80a695ae3cc3 708 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
rctaduio 0:80a695ae3cc3 709 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
rctaduio 0:80a695ae3cc3 710 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
rctaduio 0:80a695ae3cc3 711 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
rctaduio 0:80a695ae3cc3 712 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
rctaduio 0:80a695ae3cc3 713 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
rctaduio 0:80a695ae3cc3 714 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
rctaduio 0:80a695ae3cc3 715
rctaduio 0:80a695ae3cc3 716 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
rctaduio 0:80a695ae3cc3 717 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
rctaduio 0:80a695ae3cc3 718
rctaduio 0:80a695ae3cc3 719 for(ii = 0; ii < 3; ii++) {
rctaduio 0:80a695ae3cc3 720 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
rctaduio 0:80a695ae3cc3 721 }
rctaduio 0:80a695ae3cc3 722
rctaduio 0:80a695ae3cc3 723 // Construct total accelerometer bias, including calculated average accelerometer bias from above
rctaduio 0:80a695ae3cc3 724 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
rctaduio 0:80a695ae3cc3 725 accel_bias_reg[1] -= (accel_bias[1]/8);
rctaduio 0:80a695ae3cc3 726 accel_bias_reg[2] -= (accel_bias[2]/8);
rctaduio 0:80a695ae3cc3 727
rctaduio 0:80a695ae3cc3 728 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
rctaduio 0:80a695ae3cc3 729 data[1] = (accel_bias_reg[0]) & 0xFF;
rctaduio 0:80a695ae3cc3 730 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
rctaduio 0:80a695ae3cc3 731 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
rctaduio 0:80a695ae3cc3 732 data[3] = (accel_bias_reg[1]) & 0xFF;
rctaduio 0:80a695ae3cc3 733 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
rctaduio 0:80a695ae3cc3 734 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
rctaduio 0:80a695ae3cc3 735 data[5] = (accel_bias_reg[2]) & 0xFF;
rctaduio 0:80a695ae3cc3 736 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
rctaduio 0:80a695ae3cc3 737
rctaduio 0:80a695ae3cc3 738 // Apparently this is not working for the acceleration biases in the MPU-9250
rctaduio 0:80a695ae3cc3 739 // Are we handling the temperature correction bit properly?
rctaduio 0:80a695ae3cc3 740 // Push accelerometer biases to hardware registers
rctaduio 0:80a695ae3cc3 741 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
rctaduio 0:80a695ae3cc3 742 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
rctaduio 0:80a695ae3cc3 743 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
rctaduio 0:80a695ae3cc3 744 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
rctaduio 0:80a695ae3cc3 745 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
rctaduio 0:80a695ae3cc3 746 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);
rctaduio 0:80a695ae3cc3 747 */
rctaduio 0:80a695ae3cc3 748 // Output scaled accelerometer biases for manual subtraction in the main program
rctaduio 0:80a695ae3cc3 749 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity;
rctaduio 0:80a695ae3cc3 750 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity;
rctaduio 0:80a695ae3cc3 751 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
rctaduio 0:80a695ae3cc3 752 }
rctaduio 0:80a695ae3cc3 753
rctaduio 0:80a695ae3cc3 754
rctaduio 0:80a695ae3cc3 755 // Accelerometer and gyroscope self test; check calibration wrt factory settings
rctaduio 0:80a695ae3cc3 756 void MPU9250SelfTest(float * destination) { // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
rctaduio 0:80a695ae3cc3 757 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
rctaduio 0:80a695ae3cc3 758 uint8_t selfTest[6];
rctaduio 0:80a695ae3cc3 759 int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3];
rctaduio 0:80a695ae3cc3 760 float factoryTrim[6];
rctaduio 0:80a695ae3cc3 761 uint8_t FS = 0;
rctaduio 0:80a695ae3cc3 762
rctaduio 0:80a695ae3cc3 763 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
rctaduio 0:80a695ae3cc3 764 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
rctaduio 0:80a695ae3cc3 765 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
rctaduio 0:80a695ae3cc3 766 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
rctaduio 0:80a695ae3cc3 767 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
rctaduio 0:80a695ae3cc3 768
rctaduio 0:80a695ae3cc3 769 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
rctaduio 0:80a695ae3cc3 770
rctaduio 0:80a695ae3cc3 771 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
rctaduio 0:80a695ae3cc3 772 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
rctaduio 0:80a695ae3cc3 773 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
rctaduio 0:80a695ae3cc3 774 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
rctaduio 0:80a695ae3cc3 775
rctaduio 0:80a695ae3cc3 776 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
rctaduio 0:80a695ae3cc3 777 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
rctaduio 0:80a695ae3cc3 778 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
rctaduio 0:80a695ae3cc3 779 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
rctaduio 0:80a695ae3cc3 780 }
rctaduio 0:80a695ae3cc3 781
rctaduio 0:80a695ae3cc3 782 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
rctaduio 0:80a695ae3cc3 783 aAvg[ii] /= 200;
rctaduio 0:80a695ae3cc3 784 gAvg[ii] /= 200;
rctaduio 0:80a695ae3cc3 785 }
rctaduio 0:80a695ae3cc3 786
rctaduio 0:80a695ae3cc3 787 // Configure the accelerometer for self-test
rctaduio 0:80a695ae3cc3 788 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
rctaduio 0:80a695ae3cc3 789 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
rctaduio 0:80a695ae3cc3 790 wait_ms(25); // Delay a while to let the device stabilize
rctaduio 0:80a695ae3cc3 791
rctaduio 0:80a695ae3cc3 792 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
rctaduio 0:80a695ae3cc3 793
rctaduio 0:80a695ae3cc3 794 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
rctaduio 0:80a695ae3cc3 795 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
rctaduio 0:80a695ae3cc3 796 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
rctaduio 0:80a695ae3cc3 797 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
rctaduio 0:80a695ae3cc3 798
rctaduio 0:80a695ae3cc3 799 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
rctaduio 0:80a695ae3cc3 800 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
rctaduio 0:80a695ae3cc3 801 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
rctaduio 0:80a695ae3cc3 802 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
rctaduio 0:80a695ae3cc3 803 }
rctaduio 0:80a695ae3cc3 804
rctaduio 0:80a695ae3cc3 805 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
rctaduio 0:80a695ae3cc3 806 aSTAvg[ii] /= 200;
rctaduio 0:80a695ae3cc3 807 gSTAvg[ii] /= 200;
rctaduio 0:80a695ae3cc3 808 }
rctaduio 0:80a695ae3cc3 809
rctaduio 0:80a695ae3cc3 810 // Configure the gyro and accelerometer for normal operation
rctaduio 0:80a695ae3cc3 811 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
rctaduio 0:80a695ae3cc3 812 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
rctaduio 0:80a695ae3cc3 813 wait_ms(25); // Delay a while to let the device stabilize
rctaduio 0:80a695ae3cc3 814
rctaduio 0:80a695ae3cc3 815 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
rctaduio 0:80a695ae3cc3 816 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
rctaduio 0:80a695ae3cc3 817 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
rctaduio 0:80a695ae3cc3 818 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
rctaduio 0:80a695ae3cc3 819 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
rctaduio 0:80a695ae3cc3 820 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
rctaduio 0:80a695ae3cc3 821 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
rctaduio 0:80a695ae3cc3 822
rctaduio 0:80a695ae3cc3 823 // Retrieve factory self-test value from self-test code reads
rctaduio 0:80a695ae3cc3 824 factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation
rctaduio 0:80a695ae3cc3 825 factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation
rctaduio 0:80a695ae3cc3 826 factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation
rctaduio 0:80a695ae3cc3 827 factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation
rctaduio 0:80a695ae3cc3 828 factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation
rctaduio 0:80a695ae3cc3 829 factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation
rctaduio 0:80a695ae3cc3 830
rctaduio 0:80a695ae3cc3 831 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
rctaduio 0:80a695ae3cc3 832 // To get percent, must multiply by 100
rctaduio 0:80a695ae3cc3 833 for (int i = 0; i < 3; i++) {
rctaduio 0:80a695ae3cc3 834 destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences
rctaduio 0:80a695ae3cc3 835 destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences
rctaduio 0:80a695ae3cc3 836 }
rctaduio 0:80a695ae3cc3 837
rctaduio 0:80a695ae3cc3 838 }
rctaduio 0:80a695ae3cc3 839
rctaduio 0:80a695ae3cc3 840
rctaduio 0:80a695ae3cc3 841
rctaduio 0:80a695ae3cc3 842 // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
rctaduio 0:80a695ae3cc3 843 // (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
rctaduio 0:80a695ae3cc3 844 // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute
rctaduio 0:80a695ae3cc3 845 // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
rctaduio 0:80a695ae3cc3 846 // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
rctaduio 0:80a695ae3cc3 847 // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
rctaduio 0:80a695ae3cc3 848 void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) {
rctaduio 0:80a695ae3cc3 849 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
rctaduio 0:80a695ae3cc3 850 float norm;
rctaduio 0:80a695ae3cc3 851 float hx, hy, _2bx, _2bz;
rctaduio 0:80a695ae3cc3 852 float s1, s2, s3, s4;
rctaduio 0:80a695ae3cc3 853 float qDot1, qDot2, qDot3, qDot4;
rctaduio 0:80a695ae3cc3 854
rctaduio 0:80a695ae3cc3 855 // Auxiliary variables to avoid repeated arithmetic
rctaduio 0:80a695ae3cc3 856 float _2q1mx;
rctaduio 0:80a695ae3cc3 857 float _2q1my;
rctaduio 0:80a695ae3cc3 858 float _2q1mz;
rctaduio 0:80a695ae3cc3 859 float _2q2mx;
rctaduio 0:80a695ae3cc3 860 float _4bx;
rctaduio 0:80a695ae3cc3 861 float _4bz;
rctaduio 0:80a695ae3cc3 862 float _2q1 = 2.0f * q1;
rctaduio 0:80a695ae3cc3 863 float _2q2 = 2.0f * q2;
rctaduio 0:80a695ae3cc3 864 float _2q3 = 2.0f * q3;
rctaduio 0:80a695ae3cc3 865 float _2q4 = 2.0f * q4;
rctaduio 0:80a695ae3cc3 866 float _2q1q3 = 2.0f * q1 * q3;
rctaduio 0:80a695ae3cc3 867 float _2q3q4 = 2.0f * q3 * q4;
rctaduio 0:80a695ae3cc3 868 float q1q1 = q1 * q1;
rctaduio 0:80a695ae3cc3 869 float q1q2 = q1 * q2;
rctaduio 0:80a695ae3cc3 870 float q1q3 = q1 * q3;
rctaduio 0:80a695ae3cc3 871 float q1q4 = q1 * q4;
rctaduio 0:80a695ae3cc3 872 float q2q2 = q2 * q2;
rctaduio 0:80a695ae3cc3 873 float q2q3 = q2 * q3;
rctaduio 0:80a695ae3cc3 874 float q2q4 = q2 * q4;
rctaduio 0:80a695ae3cc3 875 float q3q3 = q3 * q3;
rctaduio 0:80a695ae3cc3 876 float q3q4 = q3 * q4;
rctaduio 0:80a695ae3cc3 877 float q4q4 = q4 * q4;
rctaduio 0:80a695ae3cc3 878
rctaduio 0:80a695ae3cc3 879 // Normalise accelerometer measurement
rctaduio 0:80a695ae3cc3 880 norm = sqrt(ax * ax + ay * ay + az * az);
rctaduio 0:80a695ae3cc3 881 if (norm == 0.0f) return; // handle NaN
rctaduio 0:80a695ae3cc3 882 norm = 1.0f/norm;
rctaduio 0:80a695ae3cc3 883 ax *= norm;
rctaduio 0:80a695ae3cc3 884 ay *= norm;
rctaduio 0:80a695ae3cc3 885 az *= norm;
rctaduio 0:80a695ae3cc3 886
rctaduio 0:80a695ae3cc3 887 // Normalise magnetometer measurement
rctaduio 0:80a695ae3cc3 888 norm = sqrt(mx * mx + my * my + mz * mz);
rctaduio 0:80a695ae3cc3 889 if (norm == 0.0f) return; // handle NaN
rctaduio 0:80a695ae3cc3 890 norm = 1.0f/norm;
rctaduio 0:80a695ae3cc3 891 mx *= norm;
rctaduio 0:80a695ae3cc3 892 my *= norm;
rctaduio 0:80a695ae3cc3 893 mz *= norm;
rctaduio 0:80a695ae3cc3 894
rctaduio 0:80a695ae3cc3 895 // Reference direction of Earth's magnetic field
rctaduio 0:80a695ae3cc3 896 _2q1mx = 2.0f * q1 * mx;
rctaduio 0:80a695ae3cc3 897 _2q1my = 2.0f * q1 * my;
rctaduio 0:80a695ae3cc3 898 _2q1mz = 2.0f * q1 * mz;
rctaduio 0:80a695ae3cc3 899 _2q2mx = 2.0f * q2 * mx;
rctaduio 0:80a695ae3cc3 900 hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4;
rctaduio 0:80a695ae3cc3 901 hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4;
rctaduio 0:80a695ae3cc3 902 _2bx = sqrt(hx * hx + hy * hy);
rctaduio 0:80a695ae3cc3 903 _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4;
rctaduio 0:80a695ae3cc3 904 _4bx = 2.0f * _2bx;
rctaduio 0:80a695ae3cc3 905 _4bz = 2.0f * _2bz;
rctaduio 0:80a695ae3cc3 906
rctaduio 0:80a695ae3cc3 907 // Gradient decent algorithm corrective step
rctaduio 0:80a695ae3cc3 908 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);
rctaduio 0:80a695ae3cc3 909 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);
rctaduio 0:80a695ae3cc3 910 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);
rctaduio 0:80a695ae3cc3 911 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);
rctaduio 0:80a695ae3cc3 912 norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude
rctaduio 0:80a695ae3cc3 913 norm = 1.0f/norm;
rctaduio 0:80a695ae3cc3 914 s1 *= norm;
rctaduio 0:80a695ae3cc3 915 s2 *= norm;
rctaduio 0:80a695ae3cc3 916 s3 *= norm;
rctaduio 0:80a695ae3cc3 917 s4 *= norm;
rctaduio 0:80a695ae3cc3 918
rctaduio 0:80a695ae3cc3 919 // Compute rate of change of quaternion
rctaduio 0:80a695ae3cc3 920 qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1;
rctaduio 0:80a695ae3cc3 921 qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2;
rctaduio 0:80a695ae3cc3 922 qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3;
rctaduio 0:80a695ae3cc3 923 qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4;
rctaduio 0:80a695ae3cc3 924
rctaduio 0:80a695ae3cc3 925 // Integrate to yield quaternion
rctaduio 0:80a695ae3cc3 926 q1 += qDot1 * deltat;
rctaduio 0:80a695ae3cc3 927 q2 += qDot2 * deltat;
rctaduio 0:80a695ae3cc3 928 q3 += qDot3 * deltat;
rctaduio 0:80a695ae3cc3 929 q4 += qDot4 * deltat;
rctaduio 0:80a695ae3cc3 930 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
rctaduio 0:80a695ae3cc3 931 norm = 1.0f/norm;
rctaduio 0:80a695ae3cc3 932 q[0] = q1 * norm;
rctaduio 0:80a695ae3cc3 933 q[1] = q2 * norm;
rctaduio 0:80a695ae3cc3 934 q[2] = q3 * norm;
rctaduio 0:80a695ae3cc3 935 q[3] = q4 * norm;
rctaduio 0:80a695ae3cc3 936
rctaduio 0:80a695ae3cc3 937 }
rctaduio 0:80a695ae3cc3 938
rctaduio 0:80a695ae3cc3 939
rctaduio 0:80a695ae3cc3 940 // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and
rctaduio 0:80a695ae3cc3 941 // measured ones.
rctaduio 0:80a695ae3cc3 942 void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) {
rctaduio 0:80a695ae3cc3 943 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
rctaduio 0:80a695ae3cc3 944 float norm;
rctaduio 0:80a695ae3cc3 945 float hx, hy, bx, bz;
rctaduio 0:80a695ae3cc3 946 float vx, vy, vz, wx, wy, wz;
rctaduio 0:80a695ae3cc3 947 float ex, ey, ez;
rctaduio 0:80a695ae3cc3 948 float pa, pb, pc;
rctaduio 0:80a695ae3cc3 949
rctaduio 0:80a695ae3cc3 950 // Auxiliary variables to avoid repeated arithmetic
rctaduio 0:80a695ae3cc3 951 float q1q1 = q1 * q1;
rctaduio 0:80a695ae3cc3 952 float q1q2 = q1 * q2;
rctaduio 0:80a695ae3cc3 953 float q1q3 = q1 * q3;
rctaduio 0:80a695ae3cc3 954 float q1q4 = q1 * q4;
rctaduio 0:80a695ae3cc3 955 float q2q2 = q2 * q2;
rctaduio 0:80a695ae3cc3 956 float q2q3 = q2 * q3;
rctaduio 0:80a695ae3cc3 957 float q2q4 = q2 * q4;
rctaduio 0:80a695ae3cc3 958 float q3q3 = q3 * q3;
rctaduio 0:80a695ae3cc3 959 float q3q4 = q3 * q4;
rctaduio 0:80a695ae3cc3 960 float q4q4 = q4 * q4;
rctaduio 0:80a695ae3cc3 961
rctaduio 0:80a695ae3cc3 962 // Normalise accelerometer measurement
rctaduio 0:80a695ae3cc3 963 norm = sqrt(ax * ax + ay * ay + az * az);
rctaduio 0:80a695ae3cc3 964 if (norm == 0.0f) return; // handle NaN
rctaduio 0:80a695ae3cc3 965 norm = 1.0f / norm; // use reciprocal for division
rctaduio 0:80a695ae3cc3 966 ax *= norm;
rctaduio 0:80a695ae3cc3 967 ay *= norm;
rctaduio 0:80a695ae3cc3 968 az *= norm;
rctaduio 0:80a695ae3cc3 969
rctaduio 0:80a695ae3cc3 970 // Normalise magnetometer measurement
rctaduio 0:80a695ae3cc3 971 norm = sqrt(mx * mx + my * my + mz * mz);
rctaduio 0:80a695ae3cc3 972 if (norm == 0.0f) return; // handle NaN
rctaduio 0:80a695ae3cc3 973 norm = 1.0f / norm; // use reciprocal for division
rctaduio 0:80a695ae3cc3 974 mx *= norm;
rctaduio 0:80a695ae3cc3 975 my *= norm;
rctaduio 0:80a695ae3cc3 976 mz *= norm;
rctaduio 0:80a695ae3cc3 977
rctaduio 0:80a695ae3cc3 978 // Reference direction of Earth's magnetic field
rctaduio 0:80a695ae3cc3 979 hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3);
rctaduio 0:80a695ae3cc3 980 hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2);
rctaduio 0:80a695ae3cc3 981 bx = sqrt((hx * hx) + (hy * hy));
rctaduio 0:80a695ae3cc3 982 bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3);
rctaduio 0:80a695ae3cc3 983
rctaduio 0:80a695ae3cc3 984 // Estimated direction of gravity and magnetic field
rctaduio 0:80a695ae3cc3 985 vx = 2.0f * (q2q4 - q1q3);
rctaduio 0:80a695ae3cc3 986 vy = 2.0f * (q1q2 + q3q4);
rctaduio 0:80a695ae3cc3 987 vz = q1q1 - q2q2 - q3q3 + q4q4;
rctaduio 0:80a695ae3cc3 988 wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3);
rctaduio 0:80a695ae3cc3 989 wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4);
rctaduio 0:80a695ae3cc3 990 wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3);
rctaduio 0:80a695ae3cc3 991
rctaduio 0:80a695ae3cc3 992 // Error is cross product between estimated direction and measured direction of gravity
rctaduio 0:80a695ae3cc3 993 ex = (ay * vz - az * vy) + (my * wz - mz * wy);
rctaduio 0:80a695ae3cc3 994 ey = (az * vx - ax * vz) + (mz * wx - mx * wz);
rctaduio 0:80a695ae3cc3 995 ez = (ax * vy - ay * vx) + (mx * wy - my * wx);
rctaduio 0:80a695ae3cc3 996 if (Ki > 0.0f) {
rctaduio 0:80a695ae3cc3 997 eInt[0] += ex; // accumulate integral error
rctaduio 0:80a695ae3cc3 998 eInt[1] += ey;
rctaduio 0:80a695ae3cc3 999 eInt[2] += ez;
rctaduio 0:80a695ae3cc3 1000 } else {
rctaduio 0:80a695ae3cc3 1001 eInt[0] = 0.0f; // prevent integral wind up
rctaduio 0:80a695ae3cc3 1002 eInt[1] = 0.0f;
rctaduio 0:80a695ae3cc3 1003 eInt[2] = 0.0f;
rctaduio 0:80a695ae3cc3 1004 }
rctaduio 0:80a695ae3cc3 1005
rctaduio 0:80a695ae3cc3 1006 // Apply feedback terms
rctaduio 0:80a695ae3cc3 1007 gx = gx + Kp * ex + Ki * eInt[0];
rctaduio 0:80a695ae3cc3 1008 gy = gy + Kp * ey + Ki * eInt[1];
rctaduio 0:80a695ae3cc3 1009 gz = gz + Kp * ez + Ki * eInt[2];
rctaduio 0:80a695ae3cc3 1010
rctaduio 0:80a695ae3cc3 1011 // Integrate rate of change of quaternion
rctaduio 0:80a695ae3cc3 1012 pa = q2;
rctaduio 0:80a695ae3cc3 1013 pb = q3;
rctaduio 0:80a695ae3cc3 1014 pc = q4;
rctaduio 0:80a695ae3cc3 1015 q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat);
rctaduio 0:80a695ae3cc3 1016 q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat);
rctaduio 0:80a695ae3cc3 1017 q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat);
rctaduio 0:80a695ae3cc3 1018 q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat);
rctaduio 0:80a695ae3cc3 1019
rctaduio 0:80a695ae3cc3 1020 // Normalise quaternion
rctaduio 0:80a695ae3cc3 1021 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);
rctaduio 0:80a695ae3cc3 1022 norm = 1.0f / norm;
rctaduio 0:80a695ae3cc3 1023 q[0] = q1 * norm;
rctaduio 0:80a695ae3cc3 1024 q[1] = q2 * norm;
rctaduio 0:80a695ae3cc3 1025 q[2] = q3 * norm;
rctaduio 0:80a695ae3cc3 1026 q[3] = q4 * norm;
rctaduio 0:80a695ae3cc3 1027
rctaduio 0:80a695ae3cc3 1028 }
rctaduio 0:80a695ae3cc3 1029 };
rctaduio 0:80a695ae3cc3 1030 #endif