Yuxiang Yang
Fork of
MPU6050IMU
by 
Austin Buchan
MPU6050.h@4:095b126178df, 2017-05-30 (annotated)
- Committer:
- yxyang
- Date:
- Tue May 30 06:42:08 2017 +0000
- Revision:
- 4:095b126178df
- Parent:
- 3:359efdec694f
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| onehorse | 1:cea9d83b8636 | 1 | #ifndef MPU6050_H |
| onehorse | 1:cea9d83b8636 | 2 | #define MPU6050_H |
| yxyang | 4:095b126178df | 3 | |
| onehorse | 1:cea9d83b8636 | 4 | #include "math.h" |
| yxyang | 4:095b126178df | 5 | #include "mbed.h" |
| yxyang | 4:095b126178df | 6 | |
| yxyang | 4:095b126178df | 7 | // Define registers per MPU6050, Register Map and Descriptions, Rev 4.2, |
| yxyang | 4:095b126178df | 8 | // 08/19/2013 6 DOF Motion sensor fusion device |
| onehorse | 1:cea9d83b8636 | 9 | // Invensense Inc., www.invensense.com |
| yxyang | 4:095b126178df | 10 | // See also MPU-6050 Register Map and Descriptions, Revision 4.0, |
| yxyang | 4:095b126178df | 11 | // RM-MPU-6050A-00, 9/12/2012 for registers not listed in |
| yxyang | 4:095b126178df | 12 | // above document; the MPU6050 and MPU 9150 are virtually identical but the |
| yxyang | 4:095b126178df | 13 | // latter has an on-board magnetic sensor |
| onehorse | 1:cea9d83b8636 | 14 | // |
| yxyang | 4:095b126178df | 15 | #define XGOFFS_TC \ |
| yxyang | 4:095b126178df | 16 | 0x00 // Bit 7 PWR_MODE, bits 6:1 XG_OFFS_TC, bit 0 OTP_BNK_VLD |
| yxyang | 4:095b126178df | 17 | #define YGOFFS_TC 0x01 |
| yxyang | 4:095b126178df | 18 | #define ZGOFFS_TC 0x02 |
| yxyang | 4:095b126178df | 19 | #define X_FINE_GAIN 0x03 // [7:0] fine gain |
| yxyang | 4:095b126178df | 20 | #define Y_FINE_GAIN 0x04 |
| yxyang | 4:095b126178df | 21 | #define Z_FINE_GAIN 0x05 |
| yxyang | 4:095b126178df | 22 | #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer |
| yxyang | 4:095b126178df | 23 | #define XA_OFFSET_L_TC 0x07 |
| yxyang | 4:095b126178df | 24 | #define YA_OFFSET_H 0x08 |
| yxyang | 4:095b126178df | 25 | #define YA_OFFSET_L_TC 0x09 |
| yxyang | 4:095b126178df | 26 | #define ZA_OFFSET_H 0x0A |
| yxyang | 4:095b126178df | 27 | #define ZA_OFFSET_L_TC 0x0B |
| yxyang | 4:095b126178df | 28 | #define SELF_TEST_X 0x0D |
| yxyang | 4:095b126178df | 29 | #define SELF_TEST_Y 0x0E |
| yxyang | 4:095b126178df | 30 | #define SELF_TEST_Z 0x0F |
| yxyang | 4:095b126178df | 31 | #define SELF_TEST_A 0x10 |
| yxyang | 4:095b126178df | 32 | #define XG_OFFS_USRH \ |
| yxyang | 4:095b126178df | 33 | 0x13 // User-defined trim values for gyroscope; supported in MPU-6050? |
| yxyang | 4:095b126178df | 34 | #define XG_OFFS_USRL 0x14 |
| yxyang | 4:095b126178df | 35 | #define YG_OFFS_USRH 0x15 |
| yxyang | 4:095b126178df | 36 | #define YG_OFFS_USRL 0x16 |
| yxyang | 4:095b126178df | 37 | #define ZG_OFFS_USRH 0x17 |
| yxyang | 4:095b126178df | 38 | #define ZG_OFFS_USRL 0x18 |
| yxyang | 4:095b126178df | 39 | #define SMPLRT_DIV 0x19 |
| yxyang | 4:095b126178df | 40 | #define CONFIG 0x1A |
| yxyang | 4:095b126178df | 41 | #define GYRO_CONFIG 0x1B |
| yxyang | 4:095b126178df | 42 | #define ACCEL_CONFIG 0x1C |
| yxyang | 4:095b126178df | 43 | #define FF_THR 0x1D // Free-fall |
| yxyang | 4:095b126178df | 44 | #define FF_DUR 0x1E // Free-fall |
| yxyang | 4:095b126178df | 45 | #define MOT_THR 0x1F // Motion detection threshold bits [7:0] |
| yxyang | 4:095b126178df | 46 | #define MOT_DUR \ |
| yxyang | 4:095b126178df | 47 | 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz |
| yxyang | 4:095b126178df | 48 | // rate, LSB = 1 ms |
| yxyang | 4:095b126178df | 49 | #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0] |
| yxyang | 4:095b126178df | 50 | #define ZRMOT_DUR \ |
| yxyang | 4:095b126178df | 51 | 0x22 // Duration counter threshold for zero motion interrupt generation, 16 |
| yxyang | 4:095b126178df | 52 | // Hz rate, LSB = 64 ms |
| yxyang | 4:095b126178df | 53 | #define FIFO_EN 0x23 |
| yxyang | 4:095b126178df | 54 | #define I2C_MST_CTRL 0x24 |
| yxyang | 4:095b126178df | 55 | #define I2C_SLV0_ADDR 0x25 |
| yxyang | 4:095b126178df | 56 | #define I2C_SLV0_REG 0x26 |
| yxyang | 4:095b126178df | 57 | #define I2C_SLV0_CTRL 0x27 |
| yxyang | 4:095b126178df | 58 | #define I2C_SLV1_ADDR 0x28 |
| yxyang | 4:095b126178df | 59 | #define I2C_SLV1_REG 0x29 |
| yxyang | 4:095b126178df | 60 | #define I2C_SLV1_CTRL 0x2A |
| yxyang | 4:095b126178df | 61 | #define I2C_SLV2_ADDR 0x2B |
| yxyang | 4:095b126178df | 62 | #define I2C_SLV2_REG 0x2C |
| yxyang | 4:095b126178df | 63 | #define I2C_SLV2_CTRL 0x2D |
| yxyang | 4:095b126178df | 64 | #define I2C_SLV3_ADDR 0x2E |
| yxyang | 4:095b126178df | 65 | #define I2C_SLV3_REG 0x2F |
| yxyang | 4:095b126178df | 66 | #define I2C_SLV3_CTRL 0x30 |
| yxyang | 4:095b126178df | 67 | #define I2C_SLV4_ADDR 0x31 |
| yxyang | 4:095b126178df | 68 | #define I2C_SLV4_REG 0x32 |
| yxyang | 4:095b126178df | 69 | #define I2C_SLV4_DO 0x33 |
| yxyang | 4:095b126178df | 70 | #define I2C_SLV4_CTRL 0x34 |
| yxyang | 4:095b126178df | 71 | #define I2C_SLV4_DI 0x35 |
| yxyang | 4:095b126178df | 72 | #define I2C_MST_STATUS 0x36 |
| yxyang | 4:095b126178df | 73 | #define INT_PIN_CFG 0x37 |
| yxyang | 4:095b126178df | 74 | #define INT_ENABLE 0x38 |
| yxyang | 4:095b126178df | 75 | #define DMP_INT_STATUS 0x39 // Check DMP interrupt |
| yxyang | 4:095b126178df | 76 | #define INT_STATUS 0x3A |
| yxyang | 4:095b126178df | 77 | #define ACCEL_XOUT_H 0x3B |
| yxyang | 4:095b126178df | 78 | #define ACCEL_XOUT_L 0x3C |
| yxyang | 4:095b126178df | 79 | #define ACCEL_YOUT_H 0x3D |
| yxyang | 4:095b126178df | 80 | #define ACCEL_YOUT_L 0x3E |
| yxyang | 4:095b126178df | 81 | #define ACCEL_ZOUT_H 0x3F |
| yxyang | 4:095b126178df | 82 | #define ACCEL_ZOUT_L 0x40 |
| yxyang | 4:095b126178df | 83 | #define TEMP_OUT_H 0x41 |
| yxyang | 4:095b126178df | 84 | #define TEMP_OUT_L 0x42 |
| yxyang | 4:095b126178df | 85 | #define GYRO_XOUT_H 0x43 |
| yxyang | 4:095b126178df | 86 | #define GYRO_XOUT_L 0x44 |
| yxyang | 4:095b126178df | 87 | #define GYRO_YOUT_H 0x45 |
| yxyang | 4:095b126178df | 88 | #define GYRO_YOUT_L 0x46 |
| yxyang | 4:095b126178df | 89 | #define GYRO_ZOUT_H 0x47 |
| yxyang | 4:095b126178df | 90 | #define GYRO_ZOUT_L 0x48 |
| onehorse | 1:cea9d83b8636 | 91 | #define EXT_SENS_DATA_00 0x49 |
| onehorse | 1:cea9d83b8636 | 92 | #define EXT_SENS_DATA_01 0x4A |
| onehorse | 1:cea9d83b8636 | 93 | #define EXT_SENS_DATA_02 0x4B |
| onehorse | 1:cea9d83b8636 | 94 | #define EXT_SENS_DATA_03 0x4C |
| onehorse | 1:cea9d83b8636 | 95 | #define EXT_SENS_DATA_04 0x4D |
| onehorse | 1:cea9d83b8636 | 96 | #define EXT_SENS_DATA_05 0x4E |
| onehorse | 1:cea9d83b8636 | 97 | #define EXT_SENS_DATA_06 0x4F |
| onehorse | 1:cea9d83b8636 | 98 | #define EXT_SENS_DATA_07 0x50 |
| onehorse | 1:cea9d83b8636 | 99 | #define EXT_SENS_DATA_08 0x51 |
| onehorse | 1:cea9d83b8636 | 100 | #define EXT_SENS_DATA_09 0x52 |
| onehorse | 1:cea9d83b8636 | 101 | #define EXT_SENS_DATA_10 0x53 |
| onehorse | 1:cea9d83b8636 | 102 | #define EXT_SENS_DATA_11 0x54 |
| onehorse | 1:cea9d83b8636 | 103 | #define EXT_SENS_DATA_12 0x55 |
| onehorse | 1:cea9d83b8636 | 104 | #define EXT_SENS_DATA_13 0x56 |
| onehorse | 1:cea9d83b8636 | 105 | #define EXT_SENS_DATA_14 0x57 |
| onehorse | 1:cea9d83b8636 | 106 | #define EXT_SENS_DATA_15 0x58 |
| onehorse | 1:cea9d83b8636 | 107 | #define EXT_SENS_DATA_16 0x59 |
| onehorse | 1:cea9d83b8636 | 108 | #define EXT_SENS_DATA_17 0x5A |
| onehorse | 1:cea9d83b8636 | 109 | #define EXT_SENS_DATA_18 0x5B |
| onehorse | 1:cea9d83b8636 | 110 | #define EXT_SENS_DATA_19 0x5C |
| onehorse | 1:cea9d83b8636 | 111 | #define EXT_SENS_DATA_20 0x5D |
| onehorse | 1:cea9d83b8636 | 112 | #define EXT_SENS_DATA_21 0x5E |
| onehorse | 1:cea9d83b8636 | 113 | #define EXT_SENS_DATA_22 0x5F |
| onehorse | 1:cea9d83b8636 | 114 | #define EXT_SENS_DATA_23 0x60 |
| onehorse | 1:cea9d83b8636 | 115 | #define MOT_DETECT_STATUS 0x61 |
| yxyang | 4:095b126178df | 116 | #define I2C_SLV0_DO 0x63 |
| yxyang | 4:095b126178df | 117 | #define I2C_SLV1_DO 0x64 |
| yxyang | 4:095b126178df | 118 | #define I2C_SLV2_DO 0x65 |
| yxyang | 4:095b126178df | 119 | #define I2C_SLV3_DO 0x66 |
| onehorse | 1:cea9d83b8636 | 120 | #define I2C_MST_DELAY_CTRL 0x67 |
| yxyang | 4:095b126178df | 121 | #define SIGNAL_PATH_RESET 0x68 |
| yxyang | 4:095b126178df | 122 | #define MOT_DETECT_CTRL 0x69 |
| yxyang | 4:095b126178df | 123 | #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP |
| yxyang | 4:095b126178df | 124 | #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode |
| yxyang | 4:095b126178df | 125 | #define PWR_MGMT_2 0x6C |
| yxyang | 4:095b126178df | 126 | #define DMP_BANK 0x6D // Activates a specific bank in the DMP |
| yxyang | 4:095b126178df | 127 | #define DMP_RW_PNT \ |
| yxyang | 4:095b126178df | 128 | 0x6E // Set read/write pointer to a specific start address in specified DMP |
| yxyang | 4:095b126178df | 129 | // bank |
| yxyang | 4:095b126178df | 130 | #define DMP_REG 0x6F // Register in DMP from which to read or to which to write |
| yxyang | 4:095b126178df | 131 | #define DMP_REG_1 0x70 |
| yxyang | 4:095b126178df | 132 | #define DMP_REG_2 0x71 |
| yxyang | 4:095b126178df | 133 | #define FIFO_COUNTH 0x72 |
| yxyang | 4:095b126178df | 134 | #define FIFO_COUNTL 0x73 |
| yxyang | 4:095b126178df | 135 | #define FIFO_R_W 0x74 |
| onehorse | 1:cea9d83b8636 | 136 | #define WHO_AM_I_MPU6050 0x75 // Should return 0x68 |
| onehorse | 1:cea9d83b8636 | 137 | |
| yxyang | 4:095b126178df | 138 | // Using the GY-521 breakout board, I set ADO to 0 by grounding through a 4k7 |
| yxyang | 4:095b126178df | 139 | // resistor |
| onehorse | 1:cea9d83b8636 | 140 | // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1 |
| onehorse | 1:cea9d83b8636 | 141 | #define ADO 0 |
| onehorse | 1:cea9d83b8636 | 142 | #if ADO |
| yxyang | 4:095b126178df | 143 | #define MPU6050_ADDRESS 0x69 << 1 // Device address when ADO = 1 |
| onehorse | 1:cea9d83b8636 | 144 | #else |
| yxyang | 4:095b126178df | 145 | #define MPU6050_ADDRESS 0x68 << 1 // Device address when ADO = 0 |
| onehorse | 1:cea9d83b8636 | 146 | #endif |
| onehorse | 1:cea9d83b8636 | 147 | |
| onehorse | 1:cea9d83b8636 | 148 | // Set initial input parameters |
| yxyang | 4:095b126178df | 149 | enum Ascale |
| yxyang | 4:095b126178df | 150 | { |
| onehorse | 1:cea9d83b8636 | 151 | AFS_2G = 0, |
| onehorse | 1:cea9d83b8636 | 152 | AFS_4G, |
| onehorse | 1:cea9d83b8636 | 153 | AFS_8G, |
| onehorse | 1:cea9d83b8636 | 154 | AFS_16G |
| onehorse | 1:cea9d83b8636 | 155 | }; |
| onehorse | 1:cea9d83b8636 | 156 | |
| yxyang | 4:095b126178df | 157 | enum Gscale |
| yxyang | 4:095b126178df | 158 | { |
| onehorse | 1:cea9d83b8636 | 159 | GFS_250DPS = 0, |
| onehorse | 1:cea9d83b8636 | 160 | GFS_500DPS, |
| onehorse | 1:cea9d83b8636 | 161 | GFS_1000DPS, |
| onehorse | 1:cea9d83b8636 | 162 | GFS_2000DPS |
| onehorse | 1:cea9d83b8636 | 163 | }; |
| onehorse | 1:cea9d83b8636 | 164 | |
| onehorse | 1:cea9d83b8636 | 165 | // Specify sensor full scale |
| onehorse | 1:cea9d83b8636 | 166 | int Gscale = GFS_250DPS; |
| onehorse | 1:cea9d83b8636 | 167 | int Ascale = AFS_2G; |
| onehorse | 1:cea9d83b8636 | 168 | |
| yxyang | 4:095b126178df | 169 | // Set up I2C, (SDA,SCL) |
| abuchan | 3:359efdec694f | 170 | #define MPU_SDA p9 |
| abuchan | 3:359efdec694f | 171 | #define MPU_SCL p10 |
| yxyang | 4:095b126178df | 172 | I2C i2c (MPU_SDA, MPU_SCL); |
| onehorse | 1:cea9d83b8636 | 173 | |
| yxyang | 4:095b126178df | 174 | // DigitalOut myled(LED1); |
| yxyang | 4:095b126178df | 175 | |
| onehorse | 1:cea9d83b8636 | 176 | float aRes, gRes; // scale resolutions per LSB for the sensors |
| yxyang | 4:095b126178df | 177 | |
| onehorse | 1:cea9d83b8636 | 178 | // Pin definitions |
| yxyang | 4:095b126178df | 179 | int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins |
| onehorse | 1:cea9d83b8636 | 180 | |
| yxyang | 4:095b126178df | 181 | int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output |
| yxyang | 4:095b126178df | 182 | float ax, ay, az; // Stores the real accel value in g's |
| yxyang | 4:095b126178df | 183 | int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output |
| yxyang | 4:095b126178df | 184 | float gx, gy, gz; // Stores the real gyro value in degrees per seconds |
| yxyang | 4:095b126178df | 185 | float gyroBias[3] = { 0, 0, 0 }, |
| yxyang | 4:095b126178df | 186 | accelBias[3] |
| yxyang | 4:095b126178df | 187 | = { 0, 0, 0 }; // Bias corrections for gyro and accelerometer |
| yxyang | 4:095b126178df | 188 | int16_t |
| yxyang | 4:095b126178df | 189 | tempCount; // Stores the real internal chip temperature in degrees Celsius |
| onehorse | 1:cea9d83b8636 | 190 | float temperature; |
| onehorse | 1:cea9d83b8636 | 191 | float SelfTest[6]; |
| onehorse | 1:cea9d83b8636 | 192 | |
| onehorse | 1:cea9d83b8636 | 193 | int delt_t = 0; // used to control display output rate |
| onehorse | 1:cea9d83b8636 | 194 | int count = 0; // used to control display output rate |
| onehorse | 1:cea9d83b8636 | 195 | |
| onehorse | 1:cea9d83b8636 | 196 | // parameters for 6 DoF sensor fusion calculations |
| onehorse | 1:cea9d83b8636 | 197 | float PI = 3.14159265358979323846f; |
| yxyang | 4:095b126178df | 198 | float GyroMeasError = PI * (60.0f / 180.0f); // gyroscope measurement error in |
| yxyang | 4:095b126178df | 199 | // rads/s (start at 60 deg/s), |
| yxyang | 4:095b126178df | 200 | // then reduce after ~10 s to 3 |
| yxyang | 4:095b126178df | 201 | float beta = sqrt (3.0f / 4.0f) * GyroMeasError; // compute beta |
| yxyang | 4:095b126178df | 202 | float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in |
| yxyang | 4:095b126178df | 203 | // rad/s/s (start at 0.0 deg/s/s) |
| yxyang | 4:095b126178df | 204 | float zeta = sqrt (3.0f / 4.0f) * GyroMeasDrift; // compute zeta, the other |
| yxyang | 4:095b126178df | 205 | // free parameter in the |
| yxyang | 4:095b126178df | 206 | // Madgwick scheme usually set |
| yxyang | 4:095b126178df | 207 | // to a small or zero value |
| onehorse | 1:cea9d83b8636 | 208 | float pitch, yaw, roll; |
| yxyang | 4:095b126178df | 209 | float deltat = 0.0f; // integration interval for both filter schemes |
| yxyang | 4:095b126178df | 210 | int lastUpdate = 0, firstUpdate = 0, |
| yxyang | 4:095b126178df | 211 | Now = 0; // used to calculate integration interval |
| yxyang | 4:095b126178df | 212 | // // used to calculate integration interval |
| yxyang | 4:095b126178df | 213 | float q[4] = { 1.0f, 0.0f, 0.0f, 0.0f }; // vector to hold quaternion |
| onehorse | 1:cea9d83b8636 | 214 | |
| yxyang | 4:095b126178df | 215 | class MPU6050 |
| yxyang | 4:095b126178df | 216 | { |
| yxyang | 4:095b126178df | 217 | |
| yxyang | 4:095b126178df | 218 | protected: |
| yxyang | 4:095b126178df | 219 | public: |
| onehorse | 1:cea9d83b8636 | 220 | //=================================================================================================================== |
| yxyang | 4:095b126178df | 221 | //====== Set of useful function to access acceleratio, gyroscope, and |
| yxyang | 4:095b126178df | 222 | // temperature data |
| yxyang | 4:095b126178df | 223 | //=================================================================================================================== |
| onehorse | 1:cea9d83b8636 | 224 | |
| yxyang | 4:095b126178df | 225 | void |
| yxyang | 4:095b126178df | 226 | writeByte (uint8_t address, uint8_t subAddress, uint8_t data) |
| yxyang | 4:095b126178df | 227 | { |
| yxyang | 4:095b126178df | 228 | char data_write[2]; |
| yxyang | 4:095b126178df | 229 | data_write[0] = subAddress; |
| yxyang | 4:095b126178df | 230 | data_write[1] = data; |
| yxyang | 4:095b126178df | 231 | i2c.write (address, data_write, 2, 0); |
| yxyang | 4:095b126178df | 232 | } |
| onehorse | 1:cea9d83b8636 | 233 | |
| yxyang | 4:095b126178df | 234 | char |
| yxyang | 4:095b126178df | 235 | readByte (uint8_t address, uint8_t subAddress) |
| yxyang | 4:095b126178df | 236 | { |
| yxyang | 4:095b126178df | 237 | char data[1]; // `data` will store the register data |
| onehorse | 1:cea9d83b8636 | 238 | char data_write[1]; |
| onehorse | 1:cea9d83b8636 | 239 | data_write[0] = subAddress; |
| yxyang | 4:095b126178df | 240 | i2c.write (address, data_write, 1, 1); // no stop |
| yxyang | 4:095b126178df | 241 | i2c.read (address, data, 1, 0); |
| yxyang | 4:095b126178df | 242 | return data[0]; |
| yxyang | 4:095b126178df | 243 | } |
| onehorse | 1:cea9d83b8636 | 244 | |
| yxyang | 4:095b126178df | 245 | void |
| yxyang | 4:095b126178df | 246 | readBytes (uint8_t address, uint8_t subAddress, uint8_t count, uint8_t *dest) |
| yxyang | 4:095b126178df | 247 | { |
| onehorse | 1:cea9d83b8636 | 248 | char data[14]; |
| onehorse | 1:cea9d83b8636 | 249 | char data_write[1]; |
| onehorse | 1:cea9d83b8636 | 250 | data_write[0] = subAddress; |
| yxyang | 4:095b126178df | 251 | i2c.write (address, data_write, 1, 1); // no stop |
| yxyang | 4:095b126178df | 252 | i2c.read (address, data, count, 0); |
| yxyang | 4:095b126178df | 253 | for (int ii = 0; ii < count; ii++) |
| yxyang | 4:095b126178df | 254 | { |
| yxyang | 4:095b126178df | 255 | dest[ii] = data[ii]; |
| yxyang | 4:095b126178df | 256 | } |
| yxyang | 4:095b126178df | 257 | } |
| onehorse | 1:cea9d83b8636 | 258 | |
| yxyang | 4:095b126178df | 259 | void |
| yxyang | 4:095b126178df | 260 | getGres () |
| onehorse | 1:cea9d83b8636 | 261 | { |
| yxyang | 4:095b126178df | 262 | switch (Gscale) |
| yxyang | 4:095b126178df | 263 | { |
| yxyang | 4:095b126178df | 264 | // Possible gyro scales (and their register bit settings) are: |
| yxyang | 4:095b126178df | 265 | // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11). |
| yxyang | 4:095b126178df | 266 | // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that |
| yxyang | 4:095b126178df | 267 | // 2-bit value: |
| yxyang | 4:095b126178df | 268 | case GFS_250DPS: |
| yxyang | 4:095b126178df | 269 | gRes = 250.0 / 32768.0; |
| yxyang | 4:095b126178df | 270 | break; |
| yxyang | 4:095b126178df | 271 | case GFS_500DPS: |
| yxyang | 4:095b126178df | 272 | gRes = 500.0 / 32768.0; |
| yxyang | 4:095b126178df | 273 | break; |
| yxyang | 4:095b126178df | 274 | case GFS_1000DPS: |
| yxyang | 4:095b126178df | 275 | gRes = 1000.0 / 32768.0; |
| yxyang | 4:095b126178df | 276 | break; |
| yxyang | 4:095b126178df | 277 | case GFS_2000DPS: |
| yxyang | 4:095b126178df | 278 | gRes = 2000.0 / 32768.0; |
| yxyang | 4:095b126178df | 279 | break; |
| yxyang | 4:095b126178df | 280 | } |
| onehorse | 1:cea9d83b8636 | 281 | } |
| onehorse | 1:cea9d83b8636 | 282 | |
| yxyang | 4:095b126178df | 283 | void |
| yxyang | 4:095b126178df | 284 | getAres () |
| yxyang | 4:095b126178df | 285 | { |
| yxyang | 4:095b126178df | 286 | switch (Ascale) |
| yxyang | 4:095b126178df | 287 | { |
| yxyang | 4:095b126178df | 288 | // Possible accelerometer scales (and their register bit settings) are: |
| yxyang | 4:095b126178df | 289 | // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11). |
| yxyang | 4:095b126178df | 290 | // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that |
| yxyang | 4:095b126178df | 291 | // 2-bit value: |
| yxyang | 4:095b126178df | 292 | case AFS_2G: |
| yxyang | 4:095b126178df | 293 | aRes = 2.0 / 32768.0; |
| yxyang | 4:095b126178df | 294 | break; |
| yxyang | 4:095b126178df | 295 | case AFS_4G: |
| yxyang | 4:095b126178df | 296 | aRes = 4.0 / 32768.0; |
| yxyang | 4:095b126178df | 297 | break; |
| yxyang | 4:095b126178df | 298 | case AFS_8G: |
| yxyang | 4:095b126178df | 299 | aRes = 8.0 / 32768.0; |
| yxyang | 4:095b126178df | 300 | break; |
| yxyang | 4:095b126178df | 301 | case AFS_16G: |
| yxyang | 4:095b126178df | 302 | aRes = 16.0 / 32768.0; |
| yxyang | 4:095b126178df | 303 | break; |
| yxyang | 4:095b126178df | 304 | } |
| yxyang | 4:095b126178df | 305 | } |
| onehorse | 1:cea9d83b8636 | 306 | |
| yxyang | 4:095b126178df | 307 | void |
| yxyang | 4:095b126178df | 308 | readAccelData (int16_t *destination) |
| yxyang | 4:095b126178df | 309 | { |
| yxyang | 4:095b126178df | 310 | uint8_t rawData[6]; // x/y/z accel register data stored here |
| yxyang | 4:095b126178df | 311 | readBytes (MPU6050_ADDRESS, ACCEL_XOUT_H, 6, |
| yxyang | 4:095b126178df | 312 | &rawData[0]); // Read the six raw data registers into data array |
| yxyang | 4:095b126178df | 313 | destination[0] = (int16_t) ( |
| yxyang | 4:095b126178df | 314 | ((int16_t)rawData[0] << 8) |
| yxyang | 4:095b126178df | 315 | | rawData[1]); // Turn the MSB and LSB into a signed 16-bit value |
| yxyang | 4:095b126178df | 316 | destination[1] = (int16_t) (((int16_t)rawData[2] << 8) | rawData[3]); |
| yxyang | 4:095b126178df | 317 | destination[2] = (int16_t) (((int16_t)rawData[4] << 8) | rawData[5]); |
| yxyang | 4:095b126178df | 318 | } |
| onehorse | 1:cea9d83b8636 | 319 | |
| yxyang | 4:095b126178df | 320 | void |
| yxyang | 4:095b126178df | 321 | readGyroData (int16_t *destination) |
| yxyang | 4:095b126178df | 322 | { |
| yxyang | 4:095b126178df | 323 | uint8_t rawData[6]; // x/y/z gyro register data stored here |
| yxyang | 4:095b126178df | 324 | readBytes (MPU6050_ADDRESS, GYRO_XOUT_H, 6, |
| yxyang | 4:095b126178df | 325 | &rawData[0]); // Read the six raw data registers sequentially |
| yxyang | 4:095b126178df | 326 | // into data array |
| yxyang | 4:095b126178df | 327 | destination[0] = (int16_t) ( |
| yxyang | 4:095b126178df | 328 | ((int16_t)rawData[0] << 8) |
| yxyang | 4:095b126178df | 329 | | rawData[1]); // Turn the MSB and LSB into a signed 16-bit value |
| yxyang | 4:095b126178df | 330 | destination[1] = (int16_t) (((int16_t)rawData[2] << 8) | rawData[3]); |
| yxyang | 4:095b126178df | 331 | destination[2] = (int16_t) (((int16_t)rawData[4] << 8) | rawData[5]); |
| yxyang | 4:095b126178df | 332 | } |
| onehorse | 1:cea9d83b8636 | 333 | |
| yxyang | 4:095b126178df | 334 | int16_t |
| yxyang | 4:095b126178df | 335 | readTempData () |
| yxyang | 4:095b126178df | 336 | { |
| yxyang | 4:095b126178df | 337 | uint8_t rawData[2]; // x/y/z gyro register data stored here |
| yxyang | 4:095b126178df | 338 | readBytes (MPU6050_ADDRESS, TEMP_OUT_H, 2, |
| yxyang | 4:095b126178df | 339 | &rawData[0]); // Read the two raw data registers sequentially |
| yxyang | 4:095b126178df | 340 | // into data array |
| yxyang | 4:095b126178df | 341 | return (int16_t) ( |
| yxyang | 4:095b126178df | 342 | ((int16_t)rawData[0]) << 8 |
| yxyang | 4:095b126178df | 343 | | rawData[1]); // Turn the MSB and LSB into a 16-bit value |
| yxyang | 4:095b126178df | 344 | } |
| yxyang | 4:095b126178df | 345 | |
| yxyang | 4:095b126178df | 346 | // Configure the motion detection control for low power accelerometer mode |
| yxyang | 4:095b126178df | 347 | void |
| yxyang | 4:095b126178df | 348 | LowPowerAccelOnly () |
| yxyang | 4:095b126178df | 349 | { |
| onehorse | 1:cea9d83b8636 | 350 | |
| yxyang | 4:095b126178df | 351 | // The sensor has a high-pass filter necessary to invoke to allow the |
| yxyang | 4:095b126178df | 352 | // sensor motion detection algorithms work properly |
| yxyang | 4:095b126178df | 353 | // Motion detection occurs on free-fall (acceleration below a threshold for |
| yxyang | 4:095b126178df | 354 | // some time for all axes), motion (acceleration |
| yxyang | 4:095b126178df | 355 | // above a threshold for some time on at least one axis), and zero-motion |
| yxyang | 4:095b126178df | 356 | // toggle (acceleration on each axis less than a |
| yxyang | 4:095b126178df | 357 | // threshold for some time sets this flag, motion above the threshold turns |
| yxyang | 4:095b126178df | 358 | // it off). The high-pass filter takes gravity out |
| yxyang | 4:095b126178df | 359 | // consideration for these threshold evaluations; otherwise, the flags |
| yxyang | 4:095b126178df | 360 | // would be set all the time! |
| onehorse | 1:cea9d83b8636 | 361 | |
| yxyang | 4:095b126178df | 362 | uint8_t c = readByte (MPU6050_ADDRESS, PWR_MGMT_1); |
| yxyang | 4:095b126178df | 363 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, |
| yxyang | 4:095b126178df | 364 | c & ~0x30); // Clear sleep and cycle bits [5:6] |
| yxyang | 4:095b126178df | 365 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, |
| yxyang | 4:095b126178df | 366 | c | 0x30); // Set sleep and cycle bits [5:6] to zero to make |
| yxyang | 4:095b126178df | 367 | // sure accelerometer is running |
| onehorse | 1:cea9d83b8636 | 368 | |
| yxyang | 4:095b126178df | 369 | c = readByte (MPU6050_ADDRESS, PWR_MGMT_2); |
| yxyang | 4:095b126178df | 370 | writeByte (MPU6050_ADDRESS, PWR_MGMT_2, |
| yxyang | 4:095b126178df | 371 | c & ~0x38); // Clear standby XA, YA, and ZA bits [3:5] |
| yxyang | 4:095b126178df | 372 | writeByte (MPU6050_ADDRESS, PWR_MGMT_2, |
| yxyang | 4:095b126178df | 373 | c | 0x00); // Set XA, YA, and ZA bits [3:5] to zero to make sure |
| yxyang | 4:095b126178df | 374 | // accelerometer is running |
| onehorse | 1:cea9d83b8636 | 375 | |
| yxyang | 4:095b126178df | 376 | c = readByte (MPU6050_ADDRESS, ACCEL_CONFIG); |
| yxyang | 4:095b126178df | 377 | writeByte (MPU6050_ADDRESS, ACCEL_CONFIG, |
| yxyang | 4:095b126178df | 378 | c & ~0x07); // Clear high-pass filter bits [2:0] |
| yxyang | 4:095b126178df | 379 | // Set high-pass filter to 0) reset (disable), 1) 5 Hz, 2) 2.5 Hz, 3) 1.25 |
| yxyang | 4:095b126178df | 380 | // Hz, 4) 0.63 Hz, or 7) Hold |
| yxyang | 4:095b126178df | 381 | writeByte ( |
| yxyang | 4:095b126178df | 382 | MPU6050_ADDRESS, ACCEL_CONFIG, |
| yxyang | 4:095b126178df | 383 | c | 0x00); // Set ACCEL_HPF to 0; reset mode disbaling high-pass filter |
| onehorse | 1:cea9d83b8636 | 384 | |
| yxyang | 4:095b126178df | 385 | c = readByte (MPU6050_ADDRESS, CONFIG); |
| yxyang | 4:095b126178df | 386 | writeByte (MPU6050_ADDRESS, CONFIG, |
| yxyang | 4:095b126178df | 387 | c & ~0x07); // Clear low-pass filter bits [2:0] |
| yxyang | 4:095b126178df | 388 | writeByte (MPU6050_ADDRESS, CONFIG, |
| yxyang | 4:095b126178df | 389 | c | 0x00); // Set DLPD_CFG to 0; 260 Hz bandwidth, 1 kHz rate |
| yxyang | 4:095b126178df | 390 | |
| yxyang | 4:095b126178df | 391 | c = readByte (MPU6050_ADDRESS, INT_ENABLE); |
| yxyang | 4:095b126178df | 392 | writeByte (MPU6050_ADDRESS, INT_ENABLE, c & ~0xFF); // Clear all interrupts |
| yxyang | 4:095b126178df | 393 | writeByte (MPU6050_ADDRESS, INT_ENABLE, |
| yxyang | 4:095b126178df | 394 | 0x40); // Enable motion threshold (bits 5) interrupt only |
| onehorse | 1:cea9d83b8636 | 395 | |
| yxyang | 4:095b126178df | 396 | // Motion detection interrupt requires the absolute value of any axis to |
| yxyang | 4:095b126178df | 397 | // lie above the detection threshold |
| yxyang | 4:095b126178df | 398 | // for at least the counter duration |
| yxyang | 4:095b126178df | 399 | writeByte (MPU6050_ADDRESS, MOT_THR, |
| yxyang | 4:095b126178df | 400 | 0x80); // Set motion detection to 0.256 g; LSB = 2 mg |
| yxyang | 4:095b126178df | 401 | writeByte ( |
| yxyang | 4:095b126178df | 402 | MPU6050_ADDRESS, MOT_DUR, |
| yxyang | 4:095b126178df | 403 | 0x01); // Set motion detect duration to 1 ms; LSB is 1 ms @ 1 kHz rate |
| yxyang | 4:095b126178df | 404 | |
| yxyang | 4:095b126178df | 405 | wait (0.1); // Add delay for accumulation of samples |
| onehorse | 1:cea9d83b8636 | 406 | |
| yxyang | 4:095b126178df | 407 | c = readByte (MPU6050_ADDRESS, ACCEL_CONFIG); |
| yxyang | 4:095b126178df | 408 | writeByte (MPU6050_ADDRESS, ACCEL_CONFIG, |
| yxyang | 4:095b126178df | 409 | c & ~0x07); // Clear high-pass filter bits [2:0] |
| yxyang | 4:095b126178df | 410 | writeByte (MPU6050_ADDRESS, ACCEL_CONFIG, c | 0x07); // Set ACCEL_HPF to 7; |
| yxyang | 4:095b126178df | 411 | // hold the initial |
| yxyang | 4:095b126178df | 412 | // accleration value |
| yxyang | 4:095b126178df | 413 | // as a referance |
| yxyang | 4:095b126178df | 414 | |
| yxyang | 4:095b126178df | 415 | c = readByte (MPU6050_ADDRESS, PWR_MGMT_2); |
| yxyang | 4:095b126178df | 416 | writeByte (MPU6050_ADDRESS, PWR_MGMT_2, |
| yxyang | 4:095b126178df | 417 | c & ~0xC7); // Clear standby XA, YA, and ZA bits [3:5] and |
| yxyang | 4:095b126178df | 418 | // LP_WAKE_CTRL bits [6:7] |
| yxyang | 4:095b126178df | 419 | writeByte (MPU6050_ADDRESS, PWR_MGMT_2, c | 0x47); // Set wakeup frequency |
| yxyang | 4:095b126178df | 420 | // to 5 Hz, and disable |
| yxyang | 4:095b126178df | 421 | // XG, YG, and ZG gyros |
| yxyang | 4:095b126178df | 422 | // (bits [0:2]) |
| onehorse | 1:cea9d83b8636 | 423 | |
| yxyang | 4:095b126178df | 424 | c = readByte (MPU6050_ADDRESS, PWR_MGMT_1); |
| yxyang | 4:095b126178df | 425 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, |
| yxyang | 4:095b126178df | 426 | c & ~0x20); // Clear sleep and cycle bit 5 |
| yxyang | 4:095b126178df | 427 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, c | 0x20); // Set cycle bit 5 to |
| yxyang | 4:095b126178df | 428 | // begin low power |
| yxyang | 4:095b126178df | 429 | // accelerometer motion |
| yxyang | 4:095b126178df | 430 | // interrupts |
| yxyang | 4:095b126178df | 431 | } |
| yxyang | 4:095b126178df | 432 | |
| yxyang | 4:095b126178df | 433 | void |
| yxyang | 4:095b126178df | 434 | resetMPU6050 () |
| yxyang | 4:095b126178df | 435 | { |
| yxyang | 4:095b126178df | 436 | // reset device |
| yxyang | 4:095b126178df | 437 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, |
| yxyang | 4:095b126178df | 438 | 0x80); // Write a one to bit 7 reset bit; toggle reset device |
| yxyang | 4:095b126178df | 439 | wait (0.1); |
| yxyang | 4:095b126178df | 440 | } |
| yxyang | 4:095b126178df | 441 | |
| yxyang | 4:095b126178df | 442 | void |
| yxyang | 4:095b126178df | 443 | initMPU6050 () |
| yxyang | 4:095b126178df | 444 | { |
| yxyang | 4:095b126178df | 445 | // Initialize MPU6050 device |
| yxyang | 4:095b126178df | 446 | // wake up device |
| yxyang | 4:095b126178df | 447 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, |
| yxyang | 4:095b126178df | 448 | 0x00); // Clear sleep mode bit (6), enable all sensors |
| yxyang | 4:095b126178df | 449 | wait (0.1); // Delay 100 ms for PLL to get established on x-axis gyro; |
| yxyang | 4:095b126178df | 450 | // should check for PLL ready interrupt |
| yxyang | 4:095b126178df | 451 | |
| yxyang | 4:095b126178df | 452 | // get stable time source |
| yxyang | 4:095b126178df | 453 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be |
| yxyang | 4:095b126178df | 454 | // PLL with x-axis gyroscope |
| yxyang | 4:095b126178df | 455 | // reference, bits 2:0 = 001 |
| onehorse | 1:cea9d83b8636 | 456 | |
| yxyang | 4:095b126178df | 457 | // Configure Gyro and Accelerometer |
| yxyang | 4:095b126178df | 458 | // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, |
| yxyang | 4:095b126178df | 459 | // respectively; |
| yxyang | 4:095b126178df | 460 | // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both |
| yxyang | 4:095b126178df | 461 | // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate |
| yxyang | 4:095b126178df | 462 | writeByte (MPU6050_ADDRESS, CONFIG, 0x03); |
| yxyang | 4:095b126178df | 463 | |
| yxyang | 4:095b126178df | 464 | // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV) |
| yxyang | 4:095b126178df | 465 | writeByte (MPU6050_ADDRESS, SMPLRT_DIV, |
| yxyang | 4:095b126178df | 466 | 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above |
| onehorse | 1:cea9d83b8636 | 467 | |
| yxyang | 4:095b126178df | 468 | // Set gyroscope full scale range |
| yxyang | 4:095b126178df | 469 | // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are |
| yxyang | 4:095b126178df | 470 | // left-shifted into positions 4:3 |
| yxyang | 4:095b126178df | 471 | uint8_t c = readByte (MPU6050_ADDRESS, GYRO_CONFIG); |
| yxyang | 4:095b126178df | 472 | writeByte (MPU6050_ADDRESS, GYRO_CONFIG, |
| yxyang | 4:095b126178df | 473 | c & ~0xE0); // Clear self-test bits [7:5] |
| yxyang | 4:095b126178df | 474 | writeByte (MPU6050_ADDRESS, GYRO_CONFIG, |
| yxyang | 4:095b126178df | 475 | c & ~0x18); // Clear AFS bits [4:3] |
| yxyang | 4:095b126178df | 476 | writeByte (MPU6050_ADDRESS, GYRO_CONFIG, |
| yxyang | 4:095b126178df | 477 | c | Gscale << 3); // Set full scale range for the gyro |
| onehorse | 1:cea9d83b8636 | 478 | |
| yxyang | 4:095b126178df | 479 | // Set accelerometer configuration |
| yxyang | 4:095b126178df | 480 | c = readByte (MPU6050_ADDRESS, ACCEL_CONFIG); |
| yxyang | 4:095b126178df | 481 | writeByte (MPU6050_ADDRESS, ACCEL_CONFIG, |
| yxyang | 4:095b126178df | 482 | c & ~0xE0); // Clear self-test bits [7:5] |
| yxyang | 4:095b126178df | 483 | writeByte (MPU6050_ADDRESS, ACCEL_CONFIG, |
| yxyang | 4:095b126178df | 484 | c & ~0x18); // Clear AFS bits [4:3] |
| yxyang | 4:095b126178df | 485 | writeByte (MPU6050_ADDRESS, ACCEL_CONFIG, |
| yxyang | 4:095b126178df | 486 | c | Ascale << 3); // Set full scale range for the accelerometer |
| onehorse | 1:cea9d83b8636 | 487 | |
| yxyang | 4:095b126178df | 488 | // Configure Interrupts and Bypass Enable |
| yxyang | 4:095b126178df | 489 | // Set interrupt pin active high, push-pull, and clear on read of |
| yxyang | 4:095b126178df | 490 | // INT_STATUS, enable I2C_BYPASS_EN so additional chips |
| yxyang | 4:095b126178df | 491 | // can join the I2C bus and all can be controlled by the Arduino as master |
| yxyang | 4:095b126178df | 492 | writeByte (MPU6050_ADDRESS, INT_PIN_CFG, 0x22); |
| yxyang | 4:095b126178df | 493 | writeByte (MPU6050_ADDRESS, INT_ENABLE, |
| yxyang | 4:095b126178df | 494 | 0x01); // Enable data ready (bit 0) interrupt |
| onehorse | 1:cea9d83b8636 | 495 | } |
| onehorse | 1:cea9d83b8636 | 496 | |
| yxyang | 4:095b126178df | 497 | // Function which accumulates gyro and accelerometer data after device |
| yxyang | 4:095b126178df | 498 | // initialization. It calculates the average |
| yxyang | 4:095b126178df | 499 | // of the at-rest readings and then loads the resulting offsets into |
| yxyang | 4:095b126178df | 500 | // accelerometer and gyro bias registers. |
| yxyang | 4:095b126178df | 501 | void |
| yxyang | 4:095b126178df | 502 | calibrateMPU6050 (float *dest1, float *dest2) |
| yxyang | 4:095b126178df | 503 | { |
| yxyang | 4:095b126178df | 504 | uint8_t |
| yxyang | 4:095b126178df | 505 | data[12]; // data array to hold accelerometer and gyro x, y, z, data |
| yxyang | 4:095b126178df | 506 | uint16_t ii, packet_count, fifo_count; |
| yxyang | 4:095b126178df | 507 | int32_t gyro_bias[3] = { 0, 0, 0 }, accel_bias[3] = { 0, 0, 0 }; |
| yxyang | 4:095b126178df | 508 | |
| yxyang | 4:095b126178df | 509 | // reset device, reset all registers, clear gyro and accelerometer bias |
| yxyang | 4:095b126178df | 510 | // registers |
| yxyang | 4:095b126178df | 511 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, |
| yxyang | 4:095b126178df | 512 | 0x80); // Write a one to bit 7 reset bit; toggle reset device |
| yxyang | 4:095b126178df | 513 | wait (0.1); |
| yxyang | 4:095b126178df | 514 | |
| yxyang | 4:095b126178df | 515 | // get stable time source |
| yxyang | 4:095b126178df | 516 | // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = |
| yxyang | 4:095b126178df | 517 | // 001 |
| yxyang | 4:095b126178df | 518 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, 0x01); |
| yxyang | 4:095b126178df | 519 | writeByte (MPU6050_ADDRESS, PWR_MGMT_2, 0x00); |
| yxyang | 4:095b126178df | 520 | wait (0.2); |
| yxyang | 4:095b126178df | 521 | |
| yxyang | 4:095b126178df | 522 | // Configure device for bias calculation |
| yxyang | 4:095b126178df | 523 | writeByte (MPU6050_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts |
| yxyang | 4:095b126178df | 524 | writeByte (MPU6050_ADDRESS, FIFO_EN, 0x00); // Disable FIFO |
| yxyang | 4:095b126178df | 525 | writeByte (MPU6050_ADDRESS, PWR_MGMT_1, |
| yxyang | 4:095b126178df | 526 | 0x00); // Turn on internal clock source |
| yxyang | 4:095b126178df | 527 | writeByte (MPU6050_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master |
| yxyang | 4:095b126178df | 528 | writeByte (MPU6050_ADDRESS, USER_CTRL, |
| yxyang | 4:095b126178df | 529 | 0x00); // Disable FIFO and I2C master modes |
| yxyang | 4:095b126178df | 530 | writeByte (MPU6050_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP |
| yxyang | 4:095b126178df | 531 | wait (0.015); |
| yxyang | 4:095b126178df | 532 | |
| yxyang | 4:095b126178df | 533 | // Configure MPU6050 gyro and accelerometer for bias calculation |
| yxyang | 4:095b126178df | 534 | writeByte (MPU6050_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz |
| yxyang | 4:095b126178df | 535 | writeByte (MPU6050_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz |
| yxyang | 4:095b126178df | 536 | writeByte (MPU6050_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to |
| yxyang | 4:095b126178df | 537 | // 250 degrees per second, |
| yxyang | 4:095b126178df | 538 | // maximum sensitivity |
| yxyang | 4:095b126178df | 539 | writeByte ( |
| yxyang | 4:095b126178df | 540 | MPU6050_ADDRESS, ACCEL_CONFIG, |
| yxyang | 4:095b126178df | 541 | 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity |
| yxyang | 4:095b126178df | 542 | |
| yxyang | 4:095b126178df | 543 | uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec |
| yxyang | 4:095b126178df | 544 | uint16_t accelsensitivity = 16384; // = 16384 LSB/g |
| onehorse | 1:cea9d83b8636 | 545 | |
| yxyang | 4:095b126178df | 546 | // Configure FIFO to capture accelerometer and gyro data for bias |
| yxyang | 4:095b126178df | 547 | // calculation |
| yxyang | 4:095b126178df | 548 | writeByte (MPU6050_ADDRESS, USER_CTRL, 0x40); // Enable FIFO |
| yxyang | 4:095b126178df | 549 | writeByte (MPU6050_ADDRESS, FIFO_EN, 0x78); // Enable gyro and |
| yxyang | 4:095b126178df | 550 | // accelerometer sensors for |
| yxyang | 4:095b126178df | 551 | // FIFO (max size 1024 bytes |
| yxyang | 4:095b126178df | 552 | // in MPU-6050) |
| yxyang | 4:095b126178df | 553 | wait (0.08); // accumulate 80 samples in 80 milliseconds = 960 bytes |
| yxyang | 4:095b126178df | 554 | |
| yxyang | 4:095b126178df | 555 | // At end of sample accumulation, turn off FIFO sensor read |
| yxyang | 4:095b126178df | 556 | writeByte (MPU6050_ADDRESS, FIFO_EN, |
| yxyang | 4:095b126178df | 557 | 0x00); // Disable gyro and accelerometer sensors for FIFO |
| yxyang | 4:095b126178df | 558 | readBytes (MPU6050_ADDRESS, FIFO_COUNTH, 2, |
| yxyang | 4:095b126178df | 559 | &data[0]); // read FIFO sample count |
| yxyang | 4:095b126178df | 560 | fifo_count = ((uint16_t)data[0] << 8) | data[1]; |
| yxyang | 4:095b126178df | 561 | packet_count = fifo_count / 12; // How many sets of full gyro and |
| yxyang | 4:095b126178df | 562 | // accelerometer data for averaging |
| onehorse | 1:cea9d83b8636 | 563 | |
| yxyang | 4:095b126178df | 564 | for (ii = 0; ii < packet_count; ii++) |
| yxyang | 4:095b126178df | 565 | { |
| yxyang | 4:095b126178df | 566 | int16_t accel_temp[3] = { 0, 0, 0 }, gyro_temp[3] = { 0, 0, 0 }; |
| yxyang | 4:095b126178df | 567 | readBytes (MPU6050_ADDRESS, FIFO_R_W, 12, |
| yxyang | 4:095b126178df | 568 | &data[0]); // read data for averaging |
| yxyang | 4:095b126178df | 569 | accel_temp[0] = (int16_t) ( |
| yxyang | 4:095b126178df | 570 | ((int16_t)data[0] << 8) |
| yxyang | 4:095b126178df | 571 | | data[1]); // Form signed 16-bit integer for each sample in FIFO |
| yxyang | 4:095b126178df | 572 | accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3]); |
| yxyang | 4:095b126178df | 573 | accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5]); |
| yxyang | 4:095b126178df | 574 | gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7]); |
| yxyang | 4:095b126178df | 575 | gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9]); |
| yxyang | 4:095b126178df | 576 | gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]); |
| onehorse | 1:cea9d83b8636 | 577 | |
| yxyang | 4:095b126178df | 578 | accel_bias[0] += (int32_t)accel_temp[0]; // Sum individual signed |
| yxyang | 4:095b126178df | 579 | // 16-bit biases to get |
| yxyang | 4:095b126178df | 580 | // accumulated signed 32-bit |
| yxyang | 4:095b126178df | 581 | // biases |
| yxyang | 4:095b126178df | 582 | accel_bias[1] += (int32_t)accel_temp[1]; |
| yxyang | 4:095b126178df | 583 | accel_bias[2] += (int32_t)accel_temp[2]; |
| yxyang | 4:095b126178df | 584 | gyro_bias[0] += (int32_t)gyro_temp[0]; |
| yxyang | 4:095b126178df | 585 | gyro_bias[1] += (int32_t)gyro_temp[1]; |
| yxyang | 4:095b126178df | 586 | gyro_bias[2] += (int32_t)gyro_temp[2]; |
| yxyang | 4:095b126178df | 587 | } |
| yxyang | 4:095b126178df | 588 | accel_bias[0] |
| yxyang | 4:095b126178df | 589 | /= (int32_t)packet_count; // Normalize sums to get average count biases |
| yxyang | 4:095b126178df | 590 | accel_bias[1] /= (int32_t)packet_count; |
| yxyang | 4:095b126178df | 591 | accel_bias[2] /= (int32_t)packet_count; |
| yxyang | 4:095b126178df | 592 | gyro_bias[0] /= (int32_t)packet_count; |
| yxyang | 4:095b126178df | 593 | gyro_bias[1] /= (int32_t)packet_count; |
| yxyang | 4:095b126178df | 594 | gyro_bias[2] /= (int32_t)packet_count; |
| onehorse | 1:cea9d83b8636 | 595 | |
| yxyang | 4:095b126178df | 596 | if (accel_bias[2] > 0L) |
| yxyang | 4:095b126178df | 597 | { |
| yxyang | 4:095b126178df | 598 | accel_bias[2] -= (int32_t)accelsensitivity; |
| yxyang | 4:095b126178df | 599 | } // Remove gravity from the z-axis accelerometer bias calculation |
| yxyang | 4:095b126178df | 600 | else |
| yxyang | 4:095b126178df | 601 | { |
| yxyang | 4:095b126178df | 602 | accel_bias[2] += (int32_t)accelsensitivity; |
| yxyang | 4:095b126178df | 603 | } |
| yxyang | 4:095b126178df | 604 | |
| yxyang | 4:095b126178df | 605 | // Construct the gyro biases for push to the hardware gyro bias registers, |
| yxyang | 4:095b126178df | 606 | // which are reset to zero upon device startup |
| yxyang | 4:095b126178df | 607 | data[0] = (-gyro_bias[0] / 4 >> 8) & 0xFF; // Divide by 4 to get 32.9 LSB |
| yxyang | 4:095b126178df | 608 | // per deg/s to conform to |
| yxyang | 4:095b126178df | 609 | // expected bias input format |
| yxyang | 4:095b126178df | 610 | data[1] = (-gyro_bias[0] / 4) & 0xFF; // Biases are additive, so change |
| yxyang | 4:095b126178df | 611 | // sign on calculated average gyro |
| yxyang | 4:095b126178df | 612 | // biases |
| yxyang | 4:095b126178df | 613 | data[2] = (-gyro_bias[1] / 4 >> 8) & 0xFF; |
| yxyang | 4:095b126178df | 614 | data[3] = (-gyro_bias[1] / 4) & 0xFF; |
| yxyang | 4:095b126178df | 615 | data[4] = (-gyro_bias[2] / 4 >> 8) & 0xFF; |
| yxyang | 4:095b126178df | 616 | data[5] = (-gyro_bias[2] / 4) & 0xFF; |
| yxyang | 4:095b126178df | 617 | |
| yxyang | 4:095b126178df | 618 | // Push gyro biases to hardware registers |
| yxyang | 4:095b126178df | 619 | writeByte (MPU6050_ADDRESS, XG_OFFS_USRH, data[0]); |
| yxyang | 4:095b126178df | 620 | writeByte (MPU6050_ADDRESS, XG_OFFS_USRL, data[1]); |
| yxyang | 4:095b126178df | 621 | writeByte (MPU6050_ADDRESS, YG_OFFS_USRH, data[2]); |
| yxyang | 4:095b126178df | 622 | writeByte (MPU6050_ADDRESS, YG_OFFS_USRL, data[3]); |
| yxyang | 4:095b126178df | 623 | writeByte (MPU6050_ADDRESS, ZG_OFFS_USRH, data[4]); |
| yxyang | 4:095b126178df | 624 | writeByte (MPU6050_ADDRESS, ZG_OFFS_USRL, data[5]); |
| yxyang | 4:095b126178df | 625 | |
| yxyang | 4:095b126178df | 626 | dest1[0] = (float)gyro_bias[0] |
| yxyang | 4:095b126178df | 627 | / (float)gyrosensitivity; // construct gyro bias in deg/s for |
| yxyang | 4:095b126178df | 628 | // later manual subtraction |
| yxyang | 4:095b126178df | 629 | dest1[1] = (float)gyro_bias[1] / (float)gyrosensitivity; |
| yxyang | 4:095b126178df | 630 | dest1[2] = (float)gyro_bias[2] / (float)gyrosensitivity; |
| yxyang | 4:095b126178df | 631 | |
| yxyang | 4:095b126178df | 632 | // Construct the accelerometer biases for push to the hardware |
| yxyang | 4:095b126178df | 633 | // accelerometer bias registers. These registers contain |
| yxyang | 4:095b126178df | 634 | // factory trim values which must be added to the calculated accelerometer |
| yxyang | 4:095b126178df | 635 | // biases; on boot up these registers will hold |
| yxyang | 4:095b126178df | 636 | // non-zero values. In addition, bit 0 of the lower byte must be preserved |
| yxyang | 4:095b126178df | 637 | // since it is used for temperature |
| yxyang | 4:095b126178df | 638 | // compensation calculations. Accelerometer bias registers expect bias |
| yxyang | 4:095b126178df | 639 | // input as 2048 LSB per g, so that |
| yxyang | 4:095b126178df | 640 | // the accelerometer biases calculated above must be divided by 8. |
| onehorse | 1:cea9d83b8636 | 641 | |
| yxyang | 4:095b126178df | 642 | int32_t accel_bias_reg[3] |
| yxyang | 4:095b126178df | 643 | = { 0, 0, 0 }; // A place to hold the factory accelerometer trim biases |
| yxyang | 4:095b126178df | 644 | readBytes (MPU6050_ADDRESS, XA_OFFSET_H, 2, |
| yxyang | 4:095b126178df | 645 | &data[0]); // Read factory accelerometer trim values |
| yxyang | 4:095b126178df | 646 | accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1]; |
| yxyang | 4:095b126178df | 647 | readBytes (MPU6050_ADDRESS, YA_OFFSET_H, 2, &data[0]); |
| yxyang | 4:095b126178df | 648 | accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1]; |
| yxyang | 4:095b126178df | 649 | readBytes (MPU6050_ADDRESS, ZA_OFFSET_H, 2, &data[0]); |
| yxyang | 4:095b126178df | 650 | accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1]; |
| yxyang | 4:095b126178df | 651 | |
| yxyang | 4:095b126178df | 652 | uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of |
| yxyang | 4:095b126178df | 653 | // lower byte of accelerometer bias registers |
| yxyang | 4:095b126178df | 654 | uint8_t mask_bit[3] = { |
| yxyang | 4:095b126178df | 655 | 0, 0, 0 |
| yxyang | 4:095b126178df | 656 | }; // Define array to hold mask bit for each accelerometer bias axis |
| yxyang | 4:095b126178df | 657 | |
| yxyang | 4:095b126178df | 658 | for (ii = 0; ii < 3; ii++) |
| yxyang | 4:095b126178df | 659 | { |
| yxyang | 4:095b126178df | 660 | if (accel_bias_reg[ii] & mask) |
| yxyang | 4:095b126178df | 661 | mask_bit[ii] = 0x01; // If temperature compensation bit is set, |
| yxyang | 4:095b126178df | 662 | // record that fact in mask_bit |
| yxyang | 4:095b126178df | 663 | } |
| onehorse | 1:cea9d83b8636 | 664 | |
| yxyang | 4:095b126178df | 665 | // Construct total accelerometer bias, including calculated average |
| yxyang | 4:095b126178df | 666 | // accelerometer bias from above |
| yxyang | 4:095b126178df | 667 | accel_bias_reg[0] -= (accel_bias[0] / 8); // Subtract calculated averaged |
| yxyang | 4:095b126178df | 668 | // accelerometer bias scaled to |
| yxyang | 4:095b126178df | 669 | // 2048 LSB/g (16 g full scale) |
| yxyang | 4:095b126178df | 670 | accel_bias_reg[1] -= (accel_bias[1] / 8); |
| yxyang | 4:095b126178df | 671 | accel_bias_reg[2] -= (accel_bias[2] / 8); |
| yxyang | 4:095b126178df | 672 | |
| yxyang | 4:095b126178df | 673 | data[0] = (accel_bias_reg[0] >> 8) & 0xFF; |
| yxyang | 4:095b126178df | 674 | data[1] = (accel_bias_reg[0]) & 0xFF; |
| yxyang | 4:095b126178df | 675 | data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit |
| yxyang | 4:095b126178df | 676 | // when writing back to accelerometer bias |
| yxyang | 4:095b126178df | 677 | // registers |
| yxyang | 4:095b126178df | 678 | data[2] = (accel_bias_reg[1] >> 8) & 0xFF; |
| yxyang | 4:095b126178df | 679 | data[3] = (accel_bias_reg[1]) & 0xFF; |
| yxyang | 4:095b126178df | 680 | data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit |
| yxyang | 4:095b126178df | 681 | // when writing back to accelerometer bias |
| yxyang | 4:095b126178df | 682 | // registers |
| yxyang | 4:095b126178df | 683 | data[4] = (accel_bias_reg[2] >> 8) & 0xFF; |
| yxyang | 4:095b126178df | 684 | data[5] = (accel_bias_reg[2]) & 0xFF; |
| yxyang | 4:095b126178df | 685 | data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit |
| yxyang | 4:095b126178df | 686 | // when writing back to accelerometer bias |
| yxyang | 4:095b126178df | 687 | // registers |
| yxyang | 4:095b126178df | 688 | |
| yxyang | 4:095b126178df | 689 | // Push accelerometer biases to hardware registers |
| yxyang | 4:095b126178df | 690 | // writeByte(MPU6050_ADDRESS, XA_OFFSET_H, data[0]); |
| yxyang | 4:095b126178df | 691 | // writeByte(MPU6050_ADDRESS, XA_OFFSET_L_TC, data[1]); |
| yxyang | 4:095b126178df | 692 | // writeByte(MPU6050_ADDRESS, YA_OFFSET_H, data[2]); |
| yxyang | 4:095b126178df | 693 | // writeByte(MPU6050_ADDRESS, YA_OFFSET_L_TC, data[3]); |
| yxyang | 4:095b126178df | 694 | // writeByte(MPU6050_ADDRESS, ZA_OFFSET_H, data[4]); |
| yxyang | 4:095b126178df | 695 | // writeByte(MPU6050_ADDRESS, ZA_OFFSET_L_TC, data[5]); |
| onehorse | 1:cea9d83b8636 | 696 | |
| yxyang | 4:095b126178df | 697 | // Output scaled accelerometer biases for manual subtraction in the main |
| yxyang | 4:095b126178df | 698 | // program |
| yxyang | 4:095b126178df | 699 | dest2[0] = (float)accel_bias[0] / (float)accelsensitivity; |
| yxyang | 4:095b126178df | 700 | dest2[1] = (float)accel_bias[1] / (float)accelsensitivity; |
| yxyang | 4:095b126178df | 701 | dest2[2] = (float)accel_bias[2] / (float)accelsensitivity; |
| yxyang | 4:095b126178df | 702 | } |
| yxyang | 4:095b126178df | 703 | |
| yxyang | 4:095b126178df | 704 | // Accelerometer and gyroscope self test; check calibration wrt factory |
| yxyang | 4:095b126178df | 705 | // settings |
| yxyang | 4:095b126178df | 706 | void MPU6050SelfTest (float *destination) // Should return percent deviation |
| yxyang | 4:095b126178df | 707 | // from factory trim values, +/- 14 |
| yxyang | 4:095b126178df | 708 | // or less deviation is a pass |
| yxyang | 4:095b126178df | 709 | { |
| yxyang | 4:095b126178df | 710 | uint8_t rawData[4] = { 0, 0, 0, 0 }; |
| yxyang | 4:095b126178df | 711 | uint8_t selfTest[6]; |
| yxyang | 4:095b126178df | 712 | float factoryTrim[6]; |
| onehorse | 1:cea9d83b8636 | 713 | |
| yxyang | 4:095b126178df | 714 | // Configure the accelerometer for self-test |
| yxyang | 4:095b126178df | 715 | writeByte (MPU6050_ADDRESS, ACCEL_CONFIG, 0xF0); // Enable self test on all |
| yxyang | 4:095b126178df | 716 | // three axes and set |
| yxyang | 4:095b126178df | 717 | // accelerometer range to |
| yxyang | 4:095b126178df | 718 | // +/- 8 g |
| yxyang | 4:095b126178df | 719 | writeByte (MPU6050_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all |
| yxyang | 4:095b126178df | 720 | // three axes and set gyro |
| yxyang | 4:095b126178df | 721 | // range to +/- 250 |
| yxyang | 4:095b126178df | 722 | // degrees/s |
| yxyang | 4:095b126178df | 723 | wait (0.25); // Delay a while to let the device execute the self-test |
| yxyang | 4:095b126178df | 724 | // rawData[0] |
| yxyang | 4:095b126178df | 725 | // = readByte (MPU6050_ADDRESS, SELF_TEST_X); // X-axis self-test |
| yxyang | 4:095b126178df | 726 | // results |
| yxyang | 4:095b126178df | 727 | // rawData[1] |
| yxyang | 4:095b126178df | 728 | // = readByte (MPU6050_ADDRESS, SELF_TEST_Y); // Y-axis self-test |
| yxyang | 4:095b126178df | 729 | // results |
| yxyang | 4:095b126178df | 730 | // rawData[2] |
| yxyang | 4:095b126178df | 731 | // = readByte (MPU6050_ADDRESS, SELF_TEST_Z); // Z-axis self-test |
| yxyang | 4:095b126178df | 732 | // results |
| yxyang | 4:095b126178df | 733 | // rawData[3] = readByte (MPU6050_ADDRESS, |
| yxyang | 4:095b126178df | 734 | // SELF_TEST_A); |
| yxyang | 4:095b126178df | 735 | // Mixed-axis self-test results |
| yxyang | 4:095b126178df | 736 | // Extract the acceleration test results first |
| yxyang | 4:095b126178df | 737 | selfTest[0] = (rawData[0] >> 3) |
| yxyang | 4:095b126178df | 738 | | (rawData[3] & 0x30) |
| yxyang | 4:095b126178df | 739 | >> 4; // XA_TEST result is a five-bit unsigned integer |
| yxyang | 4:095b126178df | 740 | selfTest[1] = (rawData[1] >> 3) |
| yxyang | 4:095b126178df | 741 | | (rawData[3] & 0x0C) |
| yxyang | 4:095b126178df | 742 | >> 4; // YA_TEST result is a five-bit unsigned integer |
| yxyang | 4:095b126178df | 743 | selfTest[2] = (rawData[2] >> 3) |
| yxyang | 4:095b126178df | 744 | | (rawData[3] & 0x03) |
| yxyang | 4:095b126178df | 745 | >> 4; // ZA_TEST result is a five-bit unsigned integer |
| yxyang | 4:095b126178df | 746 | // Extract the gyration test results first |
| yxyang | 4:095b126178df | 747 | selfTest[3] |
| yxyang | 4:095b126178df | 748 | = rawData[0] & 0x1F; // XG_TEST result is a five-bit unsigned integer |
| yxyang | 4:095b126178df | 749 | selfTest[4] |
| yxyang | 4:095b126178df | 750 | = rawData[1] & 0x1F; // YG_TEST result is a five-bit unsigned integer |
| yxyang | 4:095b126178df | 751 | selfTest[5] |
| yxyang | 4:095b126178df | 752 | = rawData[2] & 0x1F; // ZG_TEST result is a five-bit unsigned integer |
| yxyang | 4:095b126178df | 753 | // Process results to allow final comparison with factory set values |
| yxyang | 4:095b126178df | 754 | factoryTrim[0] = (4096.0f * 0.34f) |
| yxyang | 4:095b126178df | 755 | * (pow ((0.92f / 0.34f), |
| yxyang | 4:095b126178df | 756 | ((selfTest[0] - 1.0f) |
| yxyang | 4:095b126178df | 757 | / 30.0f))); // FT[Xa] factory trim calculation |
| yxyang | 4:095b126178df | 758 | factoryTrim[1] = (4096.0f * 0.34f) |
| yxyang | 4:095b126178df | 759 | * (pow ((0.92f / 0.34f), |
| yxyang | 4:095b126178df | 760 | ((selfTest[1] - 1.0f) |
| yxyang | 4:095b126178df | 761 | / 30.0f))); // FT[Ya] factory trim calculation |
| yxyang | 4:095b126178df | 762 | factoryTrim[2] = (4096.0f * 0.34f) |
| yxyang | 4:095b126178df | 763 | * (pow ((0.92f / 0.34f), |
| yxyang | 4:095b126178df | 764 | ((selfTest[2] - 1.0f) |
| yxyang | 4:095b126178df | 765 | / 30.0f))); // FT[Za] factory trim calculation |
| yxyang | 4:095b126178df | 766 | factoryTrim[3] |
| yxyang | 4:095b126178df | 767 | = (25.0f * 131.0f) |
| yxyang | 4:095b126178df | 768 | * (pow (1.046f, |
| yxyang | 4:095b126178df | 769 | (selfTest[3] - 1.0f))); // FT[Xg] factory trim calculation |
| yxyang | 4:095b126178df | 770 | factoryTrim[4] |
| yxyang | 4:095b126178df | 771 | = (-25.0f * 131.0f) |
| yxyang | 4:095b126178df | 772 | * (pow (1.046f, |
| yxyang | 4:095b126178df | 773 | (selfTest[4] - 1.0f))); // FT[Yg] factory trim calculation |
| yxyang | 4:095b126178df | 774 | factoryTrim[5] |
| yxyang | 4:095b126178df | 775 | = (25.0f * 131.0f) |
| yxyang | 4:095b126178df | 776 | * (pow (1.046f, |
| yxyang | 4:095b126178df | 777 | (selfTest[5] - 1.0f))); // FT[Zg] factory trim calculation |
| yxyang | 4:095b126178df | 778 | |
| yxyang | 4:095b126178df | 779 | // Output self-test results and factory trim calculation if desired |
| yxyang | 4:095b126178df | 780 | // Serial.println(selfTest[0]); Serial.println(selfTest[1]); |
| yxyang | 4:095b126178df | 781 | // Serial.println(selfTest[2]); |
| yxyang | 4:095b126178df | 782 | // Serial.println(selfTest[3]); Serial.println(selfTest[4]); |
| yxyang | 4:095b126178df | 783 | // Serial.println(selfTest[5]); |
| yxyang | 4:095b126178df | 784 | // Serial.println(factoryTrim[0]); Serial.println(factoryTrim[1]); |
| yxyang | 4:095b126178df | 785 | // Serial.println(factoryTrim[2]); |
| yxyang | 4:095b126178df | 786 | // Serial.println(factoryTrim[3]); Serial.println(factoryTrim[4]); |
| yxyang | 4:095b126178df | 787 | // Serial.println(factoryTrim[5]); |
| yxyang | 4:095b126178df | 788 | |
| yxyang | 4:095b126178df | 789 | // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim |
| yxyang | 4:095b126178df | 790 | // of the Self-Test Response |
| yxyang | 4:095b126178df | 791 | // To get to percent, must multiply by 100 and subtract result from 100 |
| yxyang | 4:095b126178df | 792 | for (int i = 0; i < 6; i++) |
| yxyang | 4:095b126178df | 793 | { |
| yxyang | 4:095b126178df | 794 | destination[i] = 100.0f |
| yxyang | 4:095b126178df | 795 | + 100.0f * (selfTest[i] - factoryTrim[i]) |
| yxyang | 4:095b126178df | 796 | / factoryTrim[i]; // Report percent differences |
| yxyang | 4:095b126178df | 797 | } |
| yxyang | 4:095b126178df | 798 | } |
| onehorse | 1:cea9d83b8636 | 799 | |
| yxyang | 4:095b126178df | 800 | // Implementation of Sebastian Madgwick's "...efficient orientation filter |
| yxyang | 4:095b126178df | 801 | // for... inertial/magnetic sensor arrays" |
| yxyang | 4:095b126178df | 802 | // (see http://www.x-io.co.uk/category/open-source/ for examples and more |
| yxyang | 4:095b126178df | 803 | // details) |
| yxyang | 4:095b126178df | 804 | // which fuses acceleration and rotation rate to produce a quaternion-based |
| yxyang | 4:095b126178df | 805 | // estimate of relative |
| yxyang | 4:095b126178df | 806 | // device orientation -- which can be converted to yaw, pitch, and roll. |
| yxyang | 4:095b126178df | 807 | // Useful for stabilizing quadcopters, etc. |
| yxyang | 4:095b126178df | 808 | // The performance of the orientation filter is at least as good as |
| yxyang | 4:095b126178df | 809 | // conventional Kalman-based filtering algorithms |
| yxyang | 4:095b126178df | 810 | // but is much less computationally intensive---it can be performed on a 3.3 |
| yxyang | 4:095b126178df | 811 | // V Pro Mini operating at 8 MHz! |
| yxyang | 4:095b126178df | 812 | void |
| yxyang | 4:095b126178df | 813 | MadgwickQuaternionUpdate (float ax, float ay, float az, float gx, float gy, |
| yxyang | 4:095b126178df | 814 | float gz) |
| yxyang | 4:095b126178df | 815 | { |
| yxyang | 4:095b126178df | 816 | float q1 = q[0], q2 = q[1], q3 = q[2], |
| yxyang | 4:095b126178df | 817 | q4 = q[3]; // short name local variable for readability |
| yxyang | 4:095b126178df | 818 | float norm; // vector norm |
| yxyang | 4:095b126178df | 819 | float f1, f2, f3; // objective funcyion elements |
| yxyang | 4:095b126178df | 820 | float J_11or24, J_12or23, J_13or22, J_14or21, J_32, |
| yxyang | 4:095b126178df | 821 | J_33; // objective function Jacobian elements |
| yxyang | 4:095b126178df | 822 | float qDot1, qDot2, qDot3, qDot4; |
| yxyang | 4:095b126178df | 823 | float hatDot1, hatDot2, hatDot3, hatDot4; |
| yxyang | 4:095b126178df | 824 | float gerrx, gerry, gerrz, gbiasx, gbiasy, gbiasz; // gyro bias error |
| yxyang | 4:095b126178df | 825 | |
| yxyang | 4:095b126178df | 826 | // Auxiliary variables to avoid repeated arithmetic |
| yxyang | 4:095b126178df | 827 | float _halfq1 = 0.5f * q1; |
| yxyang | 4:095b126178df | 828 | float _halfq2 = 0.5f * q2; |
| yxyang | 4:095b126178df | 829 | float _halfq3 = 0.5f * q3; |
| yxyang | 4:095b126178df | 830 | float _halfq4 = 0.5f * q4; |
| yxyang | 4:095b126178df | 831 | float _2q1 = 2.0f * q1; |
| yxyang | 4:095b126178df | 832 | float _2q2 = 2.0f * q2; |
| yxyang | 4:095b126178df | 833 | float _2q3 = 2.0f * q3; |
| yxyang | 4:095b126178df | 834 | float _2q4 = 2.0f * q4; |
| yxyang | 4:095b126178df | 835 | // float _2q1q3 = 2.0f * q1 * q3; |
| yxyang | 4:095b126178df | 836 | // float _2q3q4 = 2.0f * q3 * q4; |
| yxyang | 4:095b126178df | 837 | |
| yxyang | 4:095b126178df | 838 | // Normalise accelerometer measurement |
| yxyang | 4:095b126178df | 839 | norm = sqrt (ax * ax + ay * ay + az * az); |
| yxyang | 4:095b126178df | 840 | if (norm == 0.0f) |
| yxyang | 4:095b126178df | 841 | return; // handle NaN |
| yxyang | 4:095b126178df | 842 | norm = 1.0f / norm; |
| yxyang | 4:095b126178df | 843 | ax *= norm; |
| yxyang | 4:095b126178df | 844 | ay *= norm; |
| yxyang | 4:095b126178df | 845 | az *= norm; |
| onehorse | 1:cea9d83b8636 | 846 | |
| yxyang | 4:095b126178df | 847 | // Compute the objective function and Jacobian |
| yxyang | 4:095b126178df | 848 | f1 = _2q2 * q4 - _2q1 * q3 - ax; |
| yxyang | 4:095b126178df | 849 | f2 = _2q1 * q2 + _2q3 * q4 - ay; |
| yxyang | 4:095b126178df | 850 | f3 = 1.0f - _2q2 * q2 - _2q3 * q3 - az; |
| yxyang | 4:095b126178df | 851 | J_11or24 = _2q3; |
| yxyang | 4:095b126178df | 852 | J_12or23 = _2q4; |
| yxyang | 4:095b126178df | 853 | J_13or22 = _2q1; |
| yxyang | 4:095b126178df | 854 | J_14or21 = _2q2; |
| yxyang | 4:095b126178df | 855 | J_32 = 2.0f * J_14or21; |
| yxyang | 4:095b126178df | 856 | J_33 = 2.0f * J_11or24; |
| yxyang | 4:095b126178df | 857 | |
| yxyang | 4:095b126178df | 858 | // Compute the gradient (matrix multiplication) |
| yxyang | 4:095b126178df | 859 | hatDot1 = J_14or21 * f2 - J_11or24 * f1; |
| yxyang | 4:095b126178df | 860 | hatDot2 = J_12or23 * f1 + J_13or22 * f2 - J_32 * f3; |
| yxyang | 4:095b126178df | 861 | hatDot3 = J_12or23 * f2 - J_33 * f3 - J_13or22 * f1; |
| yxyang | 4:095b126178df | 862 | hatDot4 = J_14or21 * f1 + J_11or24 * f2; |
| yxyang | 4:095b126178df | 863 | |
| yxyang | 4:095b126178df | 864 | // Normalize the gradient |
| yxyang | 4:095b126178df | 865 | norm = sqrt (hatDot1 * hatDot1 + hatDot2 * hatDot2 + hatDot3 * hatDot3 |
| yxyang | 4:095b126178df | 866 | + hatDot4 * hatDot4); |
| yxyang | 4:095b126178df | 867 | hatDot1 /= norm; |
| yxyang | 4:095b126178df | 868 | hatDot2 /= norm; |
| yxyang | 4:095b126178df | 869 | hatDot3 /= norm; |
| yxyang | 4:095b126178df | 870 | hatDot4 /= norm; |
| yxyang | 4:095b126178df | 871 | |
| yxyang | 4:095b126178df | 872 | // Compute estimated gyroscope biases |
| yxyang | 4:095b126178df | 873 | gerrx = _2q1 * hatDot2 - _2q2 * hatDot1 - _2q3 * hatDot4 + _2q4 * hatDot3; |
| yxyang | 4:095b126178df | 874 | gerry = _2q1 * hatDot3 + _2q2 * hatDot4 - _2q3 * hatDot1 - _2q4 * hatDot2; |
| yxyang | 4:095b126178df | 875 | gerrz = _2q1 * hatDot4 - _2q2 * hatDot3 + _2q3 * hatDot2 - _2q4 * hatDot1; |
| onehorse | 1:cea9d83b8636 | 876 | |
| yxyang | 4:095b126178df | 877 | // Compute and remove gyroscope biases |
| yxyang | 4:095b126178df | 878 | gbiasx += gerrx * deltat * zeta; |
| yxyang | 4:095b126178df | 879 | gbiasy += gerry * deltat * zeta; |
| yxyang | 4:095b126178df | 880 | gbiasz += gerrz * deltat * zeta; |
| yxyang | 4:095b126178df | 881 | // gx -= gbiasx; |
| yxyang | 4:095b126178df | 882 | // gy -= gbiasy; |
| yxyang | 4:095b126178df | 883 | // gz -= gbiasz; |
| yxyang | 4:095b126178df | 884 | |
| yxyang | 4:095b126178df | 885 | // Compute the quaternion derivative |
| yxyang | 4:095b126178df | 886 | qDot1 = -_halfq2 * gx - _halfq3 * gy - _halfq4 * gz; |
| yxyang | 4:095b126178df | 887 | qDot2 = _halfq1 * gx + _halfq3 * gz - _halfq4 * gy; |
| yxyang | 4:095b126178df | 888 | qDot3 = _halfq1 * gy - _halfq2 * gz + _halfq4 * gx; |
| yxyang | 4:095b126178df | 889 | qDot4 = _halfq1 * gz + _halfq2 * gy - _halfq3 * gx; |
| yxyang | 4:095b126178df | 890 | |
| yxyang | 4:095b126178df | 891 | // Compute then integrate estimated quaternion derivative |
| yxyang | 4:095b126178df | 892 | q1 += (qDot1 - (beta * hatDot1)) * deltat; |
| yxyang | 4:095b126178df | 893 | q2 += (qDot2 - (beta * hatDot2)) * deltat; |
| yxyang | 4:095b126178df | 894 | q3 += (qDot3 - (beta * hatDot3)) * deltat; |
| yxyang | 4:095b126178df | 895 | q4 += (qDot4 - (beta * hatDot4)) * deltat; |
| yxyang | 4:095b126178df | 896 | |
| yxyang | 4:095b126178df | 897 | // Normalize the quaternion |
| yxyang | 4:095b126178df | 898 | norm |
| yxyang | 4:095b126178df | 899 | = sqrt (q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion |
| yxyang | 4:095b126178df | 900 | norm = 1.0f / norm; |
| yxyang | 4:095b126178df | 901 | q[0] = q1 * norm; |
| yxyang | 4:095b126178df | 902 | q[1] = q2 * norm; |
| yxyang | 4:095b126178df | 903 | q[2] = q3 * norm; |
| yxyang | 4:095b126178df | 904 | q[3] = q4 * norm; |
| yxyang | 4:095b126178df | 905 | } |
| yxyang | 4:095b126178df | 906 | }; |
| onehorse | 1:cea9d83b8636 | 907 | #endif |