Control program for FzeroX controller via USBHID interface.

Dependencies:   Radio USBDevice mbed

Fork of FzeroXcontroller by Interactive Device Design

Committer:
alexandertyler
Date:
Tue Oct 07 18:28:36 2014 +0000
Revision:
2:6c9d5fec13e3
Parent:
1:ec00f549a691
Last updates

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alexandertyler 1:ec00f549a691 1 #ifndef MPU6050_H
alexandertyler 1:ec00f549a691 2 #define MPU6050_H
alexandertyler 1:ec00f549a691 3
alexandertyler 1:ec00f549a691 4 #include "mbed.h"
alexandertyler 1:ec00f549a691 5 #include "math.h"
alexandertyler 1:ec00f549a691 6
alexandertyler 1:ec00f549a691 7 // Define registers per MPU6050, Register Map and Descriptions, Rev 4.2, 08/19/2013 6 DOF Motion sensor fusion device
alexandertyler 1:ec00f549a691 8 // Invensense Inc., www.invensense.com
alexandertyler 1:ec00f549a691 9 // See also MPU-6050 Register Map and Descriptions, Revision 4.0, RM-MPU-6050A-00, 9/12/2012 for registers not listed in
alexandertyler 1:ec00f549a691 10 // above document; the MPU6050 and MPU 9150 are virtually identical but the latter has an on-board magnetic sensor
alexandertyler 1:ec00f549a691 11 //
alexandertyler 1:ec00f549a691 12 #define XGOFFS_TC 0x00 // Bit 7 PWR_MODE, bits 6:1 XG_OFFS_TC, bit 0 OTP_BNK_VLD
alexandertyler 1:ec00f549a691 13 #define YGOFFS_TC 0x01
alexandertyler 1:ec00f549a691 14 #define ZGOFFS_TC 0x02
alexandertyler 1:ec00f549a691 15 #define X_FINE_GAIN 0x03 // [7:0] fine gain
alexandertyler 1:ec00f549a691 16 #define Y_FINE_GAIN 0x04
alexandertyler 1:ec00f549a691 17 #define Z_FINE_GAIN 0x05
alexandertyler 1:ec00f549a691 18 #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer
alexandertyler 1:ec00f549a691 19 #define XA_OFFSET_L_TC 0x07
alexandertyler 1:ec00f549a691 20 #define YA_OFFSET_H 0x08
alexandertyler 1:ec00f549a691 21 #define YA_OFFSET_L_TC 0x09
alexandertyler 1:ec00f549a691 22 #define ZA_OFFSET_H 0x0A
alexandertyler 1:ec00f549a691 23 #define ZA_OFFSET_L_TC 0x0B
alexandertyler 1:ec00f549a691 24 #define SELF_TEST_X 0x0D
alexandertyler 1:ec00f549a691 25 #define SELF_TEST_Y 0x0E
alexandertyler 1:ec00f549a691 26 #define SELF_TEST_Z 0x0F
alexandertyler 1:ec00f549a691 27 #define SELF_TEST_A 0x10
alexandertyler 1:ec00f549a691 28 #define XG_OFFS_USRH 0x13 // User-defined trim values for gyroscope; supported in MPU-6050?
alexandertyler 1:ec00f549a691 29 #define XG_OFFS_USRL 0x14
alexandertyler 1:ec00f549a691 30 #define YG_OFFS_USRH 0x15
alexandertyler 1:ec00f549a691 31 #define YG_OFFS_USRL 0x16
alexandertyler 1:ec00f549a691 32 #define ZG_OFFS_USRH 0x17
alexandertyler 1:ec00f549a691 33 #define ZG_OFFS_USRL 0x18
alexandertyler 1:ec00f549a691 34 #define SMPLRT_DIV 0x19
alexandertyler 1:ec00f549a691 35 #define CONFIG 0x1A
alexandertyler 1:ec00f549a691 36 #define GYRO_CONFIG 0x1B
alexandertyler 1:ec00f549a691 37 #define ACCEL_CONFIG 0x1C
alexandertyler 1:ec00f549a691 38 #define FF_THR 0x1D // Free-fall
alexandertyler 1:ec00f549a691 39 #define FF_DUR 0x1E // Free-fall
alexandertyler 1:ec00f549a691 40 #define MOT_THR 0x1F // Motion detection threshold bits [7:0]
alexandertyler 1:ec00f549a691 41 #define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms
alexandertyler 1:ec00f549a691 42 #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]
alexandertyler 1:ec00f549a691 43 #define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms
alexandertyler 1:ec00f549a691 44 #define FIFO_EN 0x23
alexandertyler 1:ec00f549a691 45 #define I2C_MST_CTRL 0x24
alexandertyler 1:ec00f549a691 46 #define I2C_SLV0_ADDR 0x25
alexandertyler 1:ec00f549a691 47 #define I2C_SLV0_REG 0x26
alexandertyler 1:ec00f549a691 48 #define I2C_SLV0_CTRL 0x27
alexandertyler 1:ec00f549a691 49 #define I2C_SLV1_ADDR 0x28
alexandertyler 1:ec00f549a691 50 #define I2C_SLV1_REG 0x29
alexandertyler 1:ec00f549a691 51 #define I2C_SLV1_CTRL 0x2A
alexandertyler 1:ec00f549a691 52 #define I2C_SLV2_ADDR 0x2B
alexandertyler 1:ec00f549a691 53 #define I2C_SLV2_REG 0x2C
alexandertyler 1:ec00f549a691 54 #define I2C_SLV2_CTRL 0x2D
alexandertyler 1:ec00f549a691 55 #define I2C_SLV3_ADDR 0x2E
alexandertyler 1:ec00f549a691 56 #define I2C_SLV3_REG 0x2F
alexandertyler 1:ec00f549a691 57 #define I2C_SLV3_CTRL 0x30
alexandertyler 1:ec00f549a691 58 #define I2C_SLV4_ADDR 0x31
alexandertyler 1:ec00f549a691 59 #define I2C_SLV4_REG 0x32
alexandertyler 1:ec00f549a691 60 #define I2C_SLV4_DO 0x33
alexandertyler 1:ec00f549a691 61 #define I2C_SLV4_CTRL 0x34
alexandertyler 1:ec00f549a691 62 #define I2C_SLV4_DI 0x35
alexandertyler 1:ec00f549a691 63 #define I2C_MST_STATUS 0x36
alexandertyler 1:ec00f549a691 64 #define INT_PIN_CFG 0x37
alexandertyler 1:ec00f549a691 65 #define INT_ENABLE 0x38
alexandertyler 1:ec00f549a691 66 #define DMP_INT_STATUS 0x39 // Check DMP interrupt
alexandertyler 1:ec00f549a691 67 #define INT_STATUS 0x3A
alexandertyler 1:ec00f549a691 68 #define ACCEL_XOUT_H 0x3B
alexandertyler 1:ec00f549a691 69 #define ACCEL_XOUT_L 0x3C
alexandertyler 1:ec00f549a691 70 #define ACCEL_YOUT_H 0x3D
alexandertyler 1:ec00f549a691 71 #define ACCEL_YOUT_L 0x3E
alexandertyler 1:ec00f549a691 72 #define ACCEL_ZOUT_H 0x3F
alexandertyler 1:ec00f549a691 73 #define ACCEL_ZOUT_L 0x40
alexandertyler 1:ec00f549a691 74 #define TEMP_OUT_H 0x41
alexandertyler 1:ec00f549a691 75 #define TEMP_OUT_L 0x42
alexandertyler 1:ec00f549a691 76 #define GYRO_XOUT_H 0x43
alexandertyler 1:ec00f549a691 77 #define GYRO_XOUT_L 0x44
alexandertyler 1:ec00f549a691 78 #define GYRO_YOUT_H 0x45
alexandertyler 1:ec00f549a691 79 #define GYRO_YOUT_L 0x46
alexandertyler 1:ec00f549a691 80 #define GYRO_ZOUT_H 0x47
alexandertyler 1:ec00f549a691 81 #define GYRO_ZOUT_L 0x48
alexandertyler 1:ec00f549a691 82 #define EXT_SENS_DATA_00 0x49
alexandertyler 1:ec00f549a691 83 #define EXT_SENS_DATA_01 0x4A
alexandertyler 1:ec00f549a691 84 #define EXT_SENS_DATA_02 0x4B
alexandertyler 1:ec00f549a691 85 #define EXT_SENS_DATA_03 0x4C
alexandertyler 1:ec00f549a691 86 #define EXT_SENS_DATA_04 0x4D
alexandertyler 1:ec00f549a691 87 #define EXT_SENS_DATA_05 0x4E
alexandertyler 1:ec00f549a691 88 #define EXT_SENS_DATA_06 0x4F
alexandertyler 1:ec00f549a691 89 #define EXT_SENS_DATA_07 0x50
alexandertyler 1:ec00f549a691 90 #define EXT_SENS_DATA_08 0x51
alexandertyler 1:ec00f549a691 91 #define EXT_SENS_DATA_09 0x52
alexandertyler 1:ec00f549a691 92 #define EXT_SENS_DATA_10 0x53
alexandertyler 1:ec00f549a691 93 #define EXT_SENS_DATA_11 0x54
alexandertyler 1:ec00f549a691 94 #define EXT_SENS_DATA_12 0x55
alexandertyler 1:ec00f549a691 95 #define EXT_SENS_DATA_13 0x56
alexandertyler 1:ec00f549a691 96 #define EXT_SENS_DATA_14 0x57
alexandertyler 1:ec00f549a691 97 #define EXT_SENS_DATA_15 0x58
alexandertyler 1:ec00f549a691 98 #define EXT_SENS_DATA_16 0x59
alexandertyler 1:ec00f549a691 99 #define EXT_SENS_DATA_17 0x5A
alexandertyler 1:ec00f549a691 100 #define EXT_SENS_DATA_18 0x5B
alexandertyler 1:ec00f549a691 101 #define EXT_SENS_DATA_19 0x5C
alexandertyler 1:ec00f549a691 102 #define EXT_SENS_DATA_20 0x5D
alexandertyler 1:ec00f549a691 103 #define EXT_SENS_DATA_21 0x5E
alexandertyler 1:ec00f549a691 104 #define EXT_SENS_DATA_22 0x5F
alexandertyler 1:ec00f549a691 105 #define EXT_SENS_DATA_23 0x60
alexandertyler 1:ec00f549a691 106 #define MOT_DETECT_STATUS 0x61
alexandertyler 1:ec00f549a691 107 #define I2C_SLV0_DO 0x63
alexandertyler 1:ec00f549a691 108 #define I2C_SLV1_DO 0x64
alexandertyler 1:ec00f549a691 109 #define I2C_SLV2_DO 0x65
alexandertyler 1:ec00f549a691 110 #define I2C_SLV3_DO 0x66
alexandertyler 1:ec00f549a691 111 #define I2C_MST_DELAY_CTRL 0x67
alexandertyler 1:ec00f549a691 112 #define SIGNAL_PATH_RESET 0x68
alexandertyler 1:ec00f549a691 113 #define MOT_DETECT_CTRL 0x69
alexandertyler 1:ec00f549a691 114 #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP
alexandertyler 1:ec00f549a691 115 #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode
alexandertyler 1:ec00f549a691 116 #define PWR_MGMT_2 0x6C
alexandertyler 1:ec00f549a691 117 #define DMP_BANK 0x6D // Activates a specific bank in the DMP
alexandertyler 1:ec00f549a691 118 #define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank
alexandertyler 1:ec00f549a691 119 #define DMP_REG 0x6F // Register in DMP from which to read or to which to write
alexandertyler 1:ec00f549a691 120 #define DMP_REG_1 0x70
alexandertyler 1:ec00f549a691 121 #define DMP_REG_2 0x71
alexandertyler 1:ec00f549a691 122 #define FIFO_COUNTH 0x72
alexandertyler 1:ec00f549a691 123 #define FIFO_COUNTL 0x73
alexandertyler 1:ec00f549a691 124 #define FIFO_R_W 0x74
alexandertyler 1:ec00f549a691 125 #define WHO_AM_I_MPU6050 0x75 // Should return 0x68
alexandertyler 1:ec00f549a691 126
alexandertyler 1:ec00f549a691 127 // Using the GY-521 breakout board, I set ADO to 0 by grounding through a 4k7 resistor
alexandertyler 1:ec00f549a691 128 // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1
alexandertyler 1:ec00f549a691 129 #define ADO 0
alexandertyler 1:ec00f549a691 130 #if ADO
alexandertyler 1:ec00f549a691 131 #define MPU6050_ADDRESS 0x69<<1 // Device address when ADO = 1
alexandertyler 1:ec00f549a691 132 #else
alexandertyler 1:ec00f549a691 133 #define MPU6050_ADDRESS 0x68<<1 // Device address when ADO = 0
alexandertyler 1:ec00f549a691 134 #endif
alexandertyler 1:ec00f549a691 135
alexandertyler 1:ec00f549a691 136 // Set initial input parameters
alexandertyler 1:ec00f549a691 137 enum Ascale {
alexandertyler 1:ec00f549a691 138 AFS_2G = 0,
alexandertyler 1:ec00f549a691 139 AFS_4G,
alexandertyler 1:ec00f549a691 140 AFS_8G,
alexandertyler 1:ec00f549a691 141 AFS_16G
alexandertyler 1:ec00f549a691 142 };
alexandertyler 1:ec00f549a691 143
alexandertyler 1:ec00f549a691 144 enum Gscale {
alexandertyler 1:ec00f549a691 145 GFS_250DPS = 0,
alexandertyler 1:ec00f549a691 146 GFS_500DPS,
alexandertyler 1:ec00f549a691 147 GFS_1000DPS,
alexandertyler 1:ec00f549a691 148 GFS_2000DPS
alexandertyler 1:ec00f549a691 149 };
alexandertyler 1:ec00f549a691 150
alexandertyler 1:ec00f549a691 151 // Specify sensor full scale
alexandertyler 1:ec00f549a691 152 int Gscale = GFS_2000DPS;
alexandertyler 1:ec00f549a691 153 int Ascale = AFS_16G;
alexandertyler 1:ec00f549a691 154
alexandertyler 1:ec00f549a691 155 //Set up I2C, (SDA,SCL)
alexandertyler 1:ec00f549a691 156 I2C i2c(I2C_SDA, I2C_SCL);
alexandertyler 1:ec00f549a691 157
alexandertyler 1:ec00f549a691 158 DigitalOut myled(LED1);
alexandertyler 1:ec00f549a691 159
alexandertyler 1:ec00f549a691 160 float aRes, gRes; // scale resolutions per LSB for the sensors
alexandertyler 1:ec00f549a691 161
alexandertyler 1:ec00f549a691 162 // Pin definitions
alexandertyler 1:ec00f549a691 163 int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins
alexandertyler 1:ec00f549a691 164
alexandertyler 1:ec00f549a691 165 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
alexandertyler 1:ec00f549a691 166 float ax, ay, az; // Stores the real accel value in g's
alexandertyler 1:ec00f549a691 167 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
alexandertyler 1:ec00f549a691 168 float gx, gy, gz; // Stores the real gyro value in degrees per seconds
alexandertyler 1:ec00f549a691 169 float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer
alexandertyler 1:ec00f549a691 170 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
alexandertyler 1:ec00f549a691 171 float temperature;
alexandertyler 1:ec00f549a691 172 float SelfTest[6];
alexandertyler 1:ec00f549a691 173
alexandertyler 1:ec00f549a691 174 int delt_t = 0; // used to control display output rate
alexandertyler 1:ec00f549a691 175 int count = 0; // used to control display output rate
alexandertyler 1:ec00f549a691 176
alexandertyler 1:ec00f549a691 177 // parameters for 6 DoF sensor fusion calculations
alexandertyler 1:ec00f549a691 178 float PI = 3.14159265358979323846f;
alexandertyler 1:ec00f549a691 179 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
alexandertyler 1:ec00f549a691 180 float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
alexandertyler 1:ec00f549a691 181 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
alexandertyler 1:ec00f549a691 182 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
alexandertyler 1:ec00f549a691 183 float pitch, yaw, roll;
alexandertyler 1:ec00f549a691 184 float deltat = 0.0f; // integration interval for both filter schemes
alexandertyler 1:ec00f549a691 185 int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval
alexandertyler 1:ec00f549a691 186 float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion
alexandertyler 1:ec00f549a691 187
alexandertyler 1:ec00f549a691 188 class MPU6050 {
alexandertyler 1:ec00f549a691 189
alexandertyler 1:ec00f549a691 190 protected:
alexandertyler 1:ec00f549a691 191
alexandertyler 1:ec00f549a691 192 public:
alexandertyler 1:ec00f549a691 193 //===================================================================================================================
alexandertyler 1:ec00f549a691 194 //====== Set of useful function to access acceleratio, gyroscope, and temperature data
alexandertyler 1:ec00f549a691 195 //===================================================================================================================
alexandertyler 1:ec00f549a691 196
alexandertyler 1:ec00f549a691 197 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
alexandertyler 1:ec00f549a691 198 {
alexandertyler 1:ec00f549a691 199 char data_write[2];
alexandertyler 1:ec00f549a691 200 data_write[0] = subAddress;
alexandertyler 1:ec00f549a691 201 data_write[1] = data;
alexandertyler 1:ec00f549a691 202 i2c.write(address, data_write, 2, 0);
alexandertyler 1:ec00f549a691 203 }
alexandertyler 1:ec00f549a691 204
alexandertyler 1:ec00f549a691 205 char readByte(uint8_t address, uint8_t subAddress)
alexandertyler 1:ec00f549a691 206 {
alexandertyler 1:ec00f549a691 207 char data[1]; // `data` will store the register data
alexandertyler 1:ec00f549a691 208 char data_write[1];
alexandertyler 1:ec00f549a691 209 data_write[0] = subAddress;
alexandertyler 1:ec00f549a691 210 i2c.write(address, data_write, 1, 1); // no stop
alexandertyler 1:ec00f549a691 211 i2c.read(address, data, 1, 0);
alexandertyler 1:ec00f549a691 212 return data[0];
alexandertyler 1:ec00f549a691 213 }
alexandertyler 1:ec00f549a691 214
alexandertyler 1:ec00f549a691 215 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
alexandertyler 1:ec00f549a691 216 {
alexandertyler 1:ec00f549a691 217 char data[14];
alexandertyler 1:ec00f549a691 218 char data_write[1];
alexandertyler 1:ec00f549a691 219 data_write[0] = subAddress;
alexandertyler 1:ec00f549a691 220 i2c.write(address, data_write, 1, 1); // no stop
alexandertyler 1:ec00f549a691 221 i2c.read(address, data, count, 0);
alexandertyler 1:ec00f549a691 222 for(int ii = 0; ii < count; ii++) {
alexandertyler 1:ec00f549a691 223 dest[ii] = data[ii];
alexandertyler 1:ec00f549a691 224 }
alexandertyler 1:ec00f549a691 225 }
alexandertyler 1:ec00f549a691 226
alexandertyler 1:ec00f549a691 227
alexandertyler 1:ec00f549a691 228 void getGres() {
alexandertyler 1:ec00f549a691 229 switch (Gscale)
alexandertyler 1:ec00f549a691 230 {
alexandertyler 1:ec00f549a691 231 // Possible gyro scales (and their register bit settings) are:
alexandertyler 1:ec00f549a691 232 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
alexandertyler 1:ec00f549a691 233 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
alexandertyler 1:ec00f549a691 234 case GFS_250DPS:
alexandertyler 1:ec00f549a691 235 gRes = 250.0/32768.0;
alexandertyler 1:ec00f549a691 236 break;
alexandertyler 1:ec00f549a691 237 case GFS_500DPS:
alexandertyler 1:ec00f549a691 238 gRes = 500.0/32768.0;
alexandertyler 1:ec00f549a691 239 break;
alexandertyler 1:ec00f549a691 240 case GFS_1000DPS:
alexandertyler 1:ec00f549a691 241 gRes = 1000.0/32768.0;
alexandertyler 1:ec00f549a691 242 break;
alexandertyler 1:ec00f549a691 243 case GFS_2000DPS:
alexandertyler 1:ec00f549a691 244 gRes = 2000.0/32768.0;
alexandertyler 1:ec00f549a691 245 break;
alexandertyler 1:ec00f549a691 246 }
alexandertyler 1:ec00f549a691 247 }
alexandertyler 1:ec00f549a691 248
alexandertyler 1:ec00f549a691 249 void getAres() {
alexandertyler 1:ec00f549a691 250 switch (Ascale)
alexandertyler 1:ec00f549a691 251 {
alexandertyler 1:ec00f549a691 252 // Possible accelerometer scales (and their register bit settings) are:
alexandertyler 1:ec00f549a691 253 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
alexandertyler 1:ec00f549a691 254 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
alexandertyler 1:ec00f549a691 255 case AFS_2G:
alexandertyler 1:ec00f549a691 256 aRes = 2.0/32768.0;
alexandertyler 1:ec00f549a691 257 break;
alexandertyler 1:ec00f549a691 258 case AFS_4G:
alexandertyler 1:ec00f549a691 259 aRes = 4.0/32768.0;
alexandertyler 1:ec00f549a691 260 break;
alexandertyler 1:ec00f549a691 261 case AFS_8G:
alexandertyler 1:ec00f549a691 262 aRes = 8.0/32768.0;
alexandertyler 1:ec00f549a691 263 break;
alexandertyler 1:ec00f549a691 264 case AFS_16G:
alexandertyler 1:ec00f549a691 265 aRes = 16.0/32768.0;
alexandertyler 1:ec00f549a691 266 break;
alexandertyler 1:ec00f549a691 267 }
alexandertyler 1:ec00f549a691 268 }
alexandertyler 1:ec00f549a691 269
alexandertyler 1:ec00f549a691 270
alexandertyler 1:ec00f549a691 271 void readAccelData(int16_t * destination)
alexandertyler 1:ec00f549a691 272 {
alexandertyler 1:ec00f549a691 273 uint8_t rawData[6]; // x/y/z accel register data stored here
alexandertyler 1:ec00f549a691 274 readBytes(MPU6050_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
alexandertyler 1:ec00f549a691 275 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
alexandertyler 1:ec00f549a691 276 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
alexandertyler 1:ec00f549a691 277 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
alexandertyler 1:ec00f549a691 278 }
alexandertyler 1:ec00f549a691 279
alexandertyler 1:ec00f549a691 280 void readGyroData(int16_t * destination)
alexandertyler 1:ec00f549a691 281 {
alexandertyler 1:ec00f549a691 282 uint8_t rawData[6]; // x/y/z gyro register data stored here
alexandertyler 1:ec00f549a691 283 readBytes(MPU6050_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
alexandertyler 1:ec00f549a691 284 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
alexandertyler 1:ec00f549a691 285 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
alexandertyler 1:ec00f549a691 286 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
alexandertyler 1:ec00f549a691 287 }
alexandertyler 1:ec00f549a691 288
alexandertyler 1:ec00f549a691 289 int16_t readTempData()
alexandertyler 1:ec00f549a691 290 {
alexandertyler 1:ec00f549a691 291 uint8_t rawData[2]; // x/y/z gyro register data stored here
alexandertyler 1:ec00f549a691 292 readBytes(MPU6050_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
alexandertyler 1:ec00f549a691 293 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
alexandertyler 1:ec00f549a691 294 }
alexandertyler 1:ec00f549a691 295
alexandertyler 1:ec00f549a691 296
alexandertyler 1:ec00f549a691 297
alexandertyler 1:ec00f549a691 298 // Configure the motion detection control for low power accelerometer mode
alexandertyler 1:ec00f549a691 299 void LowPowerAccelOnly()
alexandertyler 1:ec00f549a691 300 {
alexandertyler 1:ec00f549a691 301
alexandertyler 1:ec00f549a691 302 // The sensor has a high-pass filter necessary to invoke to allow the sensor motion detection algorithms work properly
alexandertyler 1:ec00f549a691 303 // Motion detection occurs on free-fall (acceleration below a threshold for some time for all axes), motion (acceleration
alexandertyler 1:ec00f549a691 304 // above a threshold for some time on at least one axis), and zero-motion toggle (acceleration on each axis less than a
alexandertyler 1:ec00f549a691 305 // threshold for some time sets this flag, motion above the threshold turns it off). The high-pass filter takes gravity out
alexandertyler 1:ec00f549a691 306 // consideration for these threshold evaluations; otherwise, the flags would be set all the time!
alexandertyler 1:ec00f549a691 307
alexandertyler 1:ec00f549a691 308 uint8_t c = readByte(MPU6050_ADDRESS, PWR_MGMT_1);
alexandertyler 1:ec00f549a691 309 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, c & ~0x30); // Clear sleep and cycle bits [5:6]
alexandertyler 1:ec00f549a691 310 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, c | 0x30); // Set sleep and cycle bits [5:6] to zero to make sure accelerometer is running
alexandertyler 1:ec00f549a691 311
alexandertyler 1:ec00f549a691 312 c = readByte(MPU6050_ADDRESS, PWR_MGMT_2);
alexandertyler 1:ec00f549a691 313 writeByte(MPU6050_ADDRESS, PWR_MGMT_2, c & ~0x38); // Clear standby XA, YA, and ZA bits [3:5]
alexandertyler 1:ec00f549a691 314 writeByte(MPU6050_ADDRESS, PWR_MGMT_2, c | 0x00); // Set XA, YA, and ZA bits [3:5] to zero to make sure accelerometer is running
alexandertyler 1:ec00f549a691 315
alexandertyler 1:ec00f549a691 316 c = readByte(MPU6050_ADDRESS, ACCEL_CONFIG);
alexandertyler 1:ec00f549a691 317 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, c & ~0x07); // Clear high-pass filter bits [2:0]
alexandertyler 1:ec00f549a691 318 // Set high-pass filter to 0) reset (disable), 1) 5 Hz, 2) 2.5 Hz, 3) 1.25 Hz, 4) 0.63 Hz, or 7) Hold
alexandertyler 1:ec00f549a691 319 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, c | 0x00); // Set ACCEL_HPF to 0; reset mode disbaling high-pass filter
alexandertyler 1:ec00f549a691 320
alexandertyler 1:ec00f549a691 321 c = readByte(MPU6050_ADDRESS, CONFIG);
alexandertyler 1:ec00f549a691 322 writeByte(MPU6050_ADDRESS, CONFIG, c & ~0x07); // Clear low-pass filter bits [2:0]
alexandertyler 1:ec00f549a691 323 writeByte(MPU6050_ADDRESS, CONFIG, c | 0x00); // Set DLPD_CFG to 0; 260 Hz bandwidth, 1 kHz rate
alexandertyler 1:ec00f549a691 324
alexandertyler 1:ec00f549a691 325 c = readByte(MPU6050_ADDRESS, INT_ENABLE);
alexandertyler 1:ec00f549a691 326 writeByte(MPU6050_ADDRESS, INT_ENABLE, c & ~0xFF); // Clear all interrupts
alexandertyler 1:ec00f549a691 327 writeByte(MPU6050_ADDRESS, INT_ENABLE, 0x40); // Enable motion threshold (bits 5) interrupt only
alexandertyler 1:ec00f549a691 328
alexandertyler 1:ec00f549a691 329 // Motion detection interrupt requires the absolute value of any axis to lie above the detection threshold
alexandertyler 1:ec00f549a691 330 // for at least the counter duration
alexandertyler 1:ec00f549a691 331 writeByte(MPU6050_ADDRESS, MOT_THR, 0x80); // Set motion detection to 0.256 g; LSB = 2 mg
alexandertyler 1:ec00f549a691 332 writeByte(MPU6050_ADDRESS, MOT_DUR, 0x01); // Set motion detect duration to 1 ms; LSB is 1 ms @ 1 kHz rate
alexandertyler 1:ec00f549a691 333
alexandertyler 1:ec00f549a691 334 wait(0.1); // Add delay for accumulation of samples
alexandertyler 1:ec00f549a691 335
alexandertyler 1:ec00f549a691 336 c = readByte(MPU6050_ADDRESS, ACCEL_CONFIG);
alexandertyler 1:ec00f549a691 337 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, c & ~0x07); // Clear high-pass filter bits [2:0]
alexandertyler 1:ec00f549a691 338 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, c | 0x07); // Set ACCEL_HPF to 7; hold the initial accleration value as a referance
alexandertyler 1:ec00f549a691 339
alexandertyler 1:ec00f549a691 340 c = readByte(MPU6050_ADDRESS, PWR_MGMT_2);
alexandertyler 1:ec00f549a691 341 writeByte(MPU6050_ADDRESS, PWR_MGMT_2, c & ~0xC7); // Clear standby XA, YA, and ZA bits [3:5] and LP_WAKE_CTRL bits [6:7]
alexandertyler 1:ec00f549a691 342 writeByte(MPU6050_ADDRESS, PWR_MGMT_2, c | 0x47); // Set wakeup frequency to 5 Hz, and disable XG, YG, and ZG gyros (bits [0:2])
alexandertyler 1:ec00f549a691 343
alexandertyler 1:ec00f549a691 344 c = readByte(MPU6050_ADDRESS, PWR_MGMT_1);
alexandertyler 1:ec00f549a691 345 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, c & ~0x20); // Clear sleep and cycle bit 5
alexandertyler 1:ec00f549a691 346 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, c | 0x20); // Set cycle bit 5 to begin low power accelerometer motion interrupts
alexandertyler 1:ec00f549a691 347
alexandertyler 1:ec00f549a691 348 }
alexandertyler 1:ec00f549a691 349
alexandertyler 1:ec00f549a691 350
alexandertyler 1:ec00f549a691 351 void resetMPU6050() {
alexandertyler 1:ec00f549a691 352 // reset device
alexandertyler 1:ec00f549a691 353 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
alexandertyler 1:ec00f549a691 354 wait(0.1);
alexandertyler 1:ec00f549a691 355 }
alexandertyler 1:ec00f549a691 356
alexandertyler 1:ec00f549a691 357
alexandertyler 1:ec00f549a691 358 void initMPU6050()
alexandertyler 1:ec00f549a691 359 {
alexandertyler 1:ec00f549a691 360 // Initialize MPU6050 device
alexandertyler 1:ec00f549a691 361 // wake up device
alexandertyler 1:ec00f549a691 362 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
alexandertyler 1:ec00f549a691 363 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
alexandertyler 1:ec00f549a691 364
alexandertyler 1:ec00f549a691 365 // get stable time source
alexandertyler 1:ec00f549a691 366 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
alexandertyler 1:ec00f549a691 367
alexandertyler 1:ec00f549a691 368 // Configure Gyro and Accelerometer
alexandertyler 1:ec00f549a691 369 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
alexandertyler 1:ec00f549a691 370 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
alexandertyler 1:ec00f549a691 371 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
alexandertyler 1:ec00f549a691 372 writeByte(MPU6050_ADDRESS, CONFIG, 0x03);
alexandertyler 1:ec00f549a691 373
alexandertyler 1:ec00f549a691 374 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
alexandertyler 1:ec00f549a691 375 writeByte(MPU6050_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
alexandertyler 1:ec00f549a691 376
alexandertyler 1:ec00f549a691 377 // Set gyroscope full scale range
alexandertyler 1:ec00f549a691 378 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
alexandertyler 1:ec00f549a691 379 uint8_t c = readByte(MPU6050_ADDRESS, GYRO_CONFIG);
alexandertyler 1:ec00f549a691 380 writeByte(MPU6050_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
alexandertyler 1:ec00f549a691 381 writeByte(MPU6050_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
alexandertyler 1:ec00f549a691 382 writeByte(MPU6050_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
alexandertyler 1:ec00f549a691 383
alexandertyler 1:ec00f549a691 384 // Set accelerometer configuration
alexandertyler 1:ec00f549a691 385 c = readByte(MPU6050_ADDRESS, ACCEL_CONFIG);
alexandertyler 1:ec00f549a691 386 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
alexandertyler 1:ec00f549a691 387 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
alexandertyler 1:ec00f549a691 388 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
alexandertyler 1:ec00f549a691 389
alexandertyler 1:ec00f549a691 390 // Configure Interrupts and Bypass Enable
alexandertyler 1:ec00f549a691 391 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
alexandertyler 1:ec00f549a691 392 // can join the I2C bus and all can be controlled by the Arduino as master
alexandertyler 1:ec00f549a691 393 writeByte(MPU6050_ADDRESS, INT_PIN_CFG, 0x22);
alexandertyler 1:ec00f549a691 394 writeByte(MPU6050_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
alexandertyler 1:ec00f549a691 395 }
alexandertyler 1:ec00f549a691 396
alexandertyler 1:ec00f549a691 397 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
alexandertyler 1:ec00f549a691 398 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
alexandertyler 1:ec00f549a691 399 void calibrateMPU6050(float * dest1, float * dest2)
alexandertyler 1:ec00f549a691 400 {
alexandertyler 1:ec00f549a691 401 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
alexandertyler 1:ec00f549a691 402 uint16_t ii, packet_count, fifo_count;
alexandertyler 1:ec00f549a691 403 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
alexandertyler 1:ec00f549a691 404
alexandertyler 1:ec00f549a691 405 // reset device, reset all registers, clear gyro and accelerometer bias registers
alexandertyler 1:ec00f549a691 406 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
alexandertyler 1:ec00f549a691 407 wait(0.1);
alexandertyler 1:ec00f549a691 408
alexandertyler 1:ec00f549a691 409 // get stable time source
alexandertyler 1:ec00f549a691 410 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
alexandertyler 1:ec00f549a691 411 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, 0x01);
alexandertyler 1:ec00f549a691 412 writeByte(MPU6050_ADDRESS, PWR_MGMT_2, 0x00);
alexandertyler 1:ec00f549a691 413 wait(0.2);
alexandertyler 1:ec00f549a691 414
alexandertyler 1:ec00f549a691 415 // Configure device for bias calculation
alexandertyler 1:ec00f549a691 416 writeByte(MPU6050_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
alexandertyler 1:ec00f549a691 417 writeByte(MPU6050_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
alexandertyler 1:ec00f549a691 418 writeByte(MPU6050_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
alexandertyler 1:ec00f549a691 419 writeByte(MPU6050_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
alexandertyler 1:ec00f549a691 420 writeByte(MPU6050_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
alexandertyler 1:ec00f549a691 421 writeByte(MPU6050_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
alexandertyler 1:ec00f549a691 422 wait(0.015);
alexandertyler 1:ec00f549a691 423
alexandertyler 1:ec00f549a691 424 // Configure MPU6050 gyro and accelerometer for bias calculation
alexandertyler 1:ec00f549a691 425 writeByte(MPU6050_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
alexandertyler 1:ec00f549a691 426 writeByte(MPU6050_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
alexandertyler 1:ec00f549a691 427 writeByte(MPU6050_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
alexandertyler 1:ec00f549a691 428 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
alexandertyler 1:ec00f549a691 429
alexandertyler 1:ec00f549a691 430 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
alexandertyler 1:ec00f549a691 431 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
alexandertyler 1:ec00f549a691 432
alexandertyler 1:ec00f549a691 433 // Configure FIFO to capture accelerometer and gyro data for bias calculation
alexandertyler 1:ec00f549a691 434 writeByte(MPU6050_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
alexandertyler 1:ec00f549a691 435 writeByte(MPU6050_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 1024 bytes in MPU-6050)
alexandertyler 1:ec00f549a691 436 wait(0.08); // accumulate 80 samples in 80 milliseconds = 960 bytes
alexandertyler 1:ec00f549a691 437
alexandertyler 1:ec00f549a691 438 // At end of sample accumulation, turn off FIFO sensor read
alexandertyler 1:ec00f549a691 439 writeByte(MPU6050_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
alexandertyler 1:ec00f549a691 440 readBytes(MPU6050_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
alexandertyler 1:ec00f549a691 441 fifo_count = ((uint16_t)data[0] << 8) | data[1];
alexandertyler 1:ec00f549a691 442 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
alexandertyler 1:ec00f549a691 443
alexandertyler 1:ec00f549a691 444 for (ii = 0; ii < packet_count; ii++) {
alexandertyler 1:ec00f549a691 445 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
alexandertyler 1:ec00f549a691 446 readBytes(MPU6050_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
alexandertyler 1:ec00f549a691 447 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
alexandertyler 1:ec00f549a691 448 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
alexandertyler 1:ec00f549a691 449 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
alexandertyler 1:ec00f549a691 450 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
alexandertyler 1:ec00f549a691 451 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
alexandertyler 1:ec00f549a691 452 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
alexandertyler 1:ec00f549a691 453
alexandertyler 1:ec00f549a691 454 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
alexandertyler 1:ec00f549a691 455 accel_bias[1] += (int32_t) accel_temp[1];
alexandertyler 1:ec00f549a691 456 accel_bias[2] += (int32_t) accel_temp[2];
alexandertyler 1:ec00f549a691 457 gyro_bias[0] += (int32_t) gyro_temp[0];
alexandertyler 1:ec00f549a691 458 gyro_bias[1] += (int32_t) gyro_temp[1];
alexandertyler 1:ec00f549a691 459 gyro_bias[2] += (int32_t) gyro_temp[2];
alexandertyler 1:ec00f549a691 460
alexandertyler 1:ec00f549a691 461 }
alexandertyler 1:ec00f549a691 462 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
alexandertyler 1:ec00f549a691 463 accel_bias[1] /= (int32_t) packet_count;
alexandertyler 1:ec00f549a691 464 accel_bias[2] /= (int32_t) packet_count;
alexandertyler 1:ec00f549a691 465 gyro_bias[0] /= (int32_t) packet_count;
alexandertyler 1:ec00f549a691 466 gyro_bias[1] /= (int32_t) packet_count;
alexandertyler 1:ec00f549a691 467 gyro_bias[2] /= (int32_t) packet_count;
alexandertyler 1:ec00f549a691 468
alexandertyler 1:ec00f549a691 469 if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation
alexandertyler 1:ec00f549a691 470 else {accel_bias[2] += (int32_t) accelsensitivity;}
alexandertyler 1:ec00f549a691 471
alexandertyler 1:ec00f549a691 472 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
alexandertyler 1:ec00f549a691 473 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
alexandertyler 1:ec00f549a691 474 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
alexandertyler 1:ec00f549a691 475 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
alexandertyler 1:ec00f549a691 476 data[3] = (-gyro_bias[1]/4) & 0xFF;
alexandertyler 1:ec00f549a691 477 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
alexandertyler 1:ec00f549a691 478 data[5] = (-gyro_bias[2]/4) & 0xFF;
alexandertyler 1:ec00f549a691 479
alexandertyler 1:ec00f549a691 480 // Push gyro biases to hardware registers
alexandertyler 1:ec00f549a691 481 writeByte(MPU6050_ADDRESS, XG_OFFS_USRH, data[0]);
alexandertyler 1:ec00f549a691 482 writeByte(MPU6050_ADDRESS, XG_OFFS_USRL, data[1]);
alexandertyler 1:ec00f549a691 483 writeByte(MPU6050_ADDRESS, YG_OFFS_USRH, data[2]);
alexandertyler 1:ec00f549a691 484 writeByte(MPU6050_ADDRESS, YG_OFFS_USRL, data[3]);
alexandertyler 1:ec00f549a691 485 writeByte(MPU6050_ADDRESS, ZG_OFFS_USRH, data[4]);
alexandertyler 1:ec00f549a691 486 writeByte(MPU6050_ADDRESS, ZG_OFFS_USRL, data[5]);
alexandertyler 1:ec00f549a691 487
alexandertyler 1:ec00f549a691 488 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
alexandertyler 1:ec00f549a691 489 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
alexandertyler 1:ec00f549a691 490 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
alexandertyler 1:ec00f549a691 491
alexandertyler 1:ec00f549a691 492 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
alexandertyler 1:ec00f549a691 493 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
alexandertyler 1:ec00f549a691 494 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
alexandertyler 1:ec00f549a691 495 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
alexandertyler 1:ec00f549a691 496 // the accelerometer biases calculated above must be divided by 8.
alexandertyler 1:ec00f549a691 497
alexandertyler 1:ec00f549a691 498 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
alexandertyler 1:ec00f549a691 499 readBytes(MPU6050_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
alexandertyler 1:ec00f549a691 500 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
alexandertyler 1:ec00f549a691 501 readBytes(MPU6050_ADDRESS, YA_OFFSET_H, 2, &data[0]);
alexandertyler 1:ec00f549a691 502 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
alexandertyler 1:ec00f549a691 503 readBytes(MPU6050_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
alexandertyler 1:ec00f549a691 504 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
alexandertyler 1:ec00f549a691 505
alexandertyler 1:ec00f549a691 506 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
alexandertyler 1:ec00f549a691 507 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
alexandertyler 1:ec00f549a691 508
alexandertyler 1:ec00f549a691 509 for(ii = 0; ii < 3; ii++) {
alexandertyler 1:ec00f549a691 510 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
alexandertyler 1:ec00f549a691 511 }
alexandertyler 1:ec00f549a691 512
alexandertyler 1:ec00f549a691 513 // Construct total accelerometer bias, including calculated average accelerometer bias from above
alexandertyler 1:ec00f549a691 514 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
alexandertyler 1:ec00f549a691 515 accel_bias_reg[1] -= (accel_bias[1]/8);
alexandertyler 1:ec00f549a691 516 accel_bias_reg[2] -= (accel_bias[2]/8);
alexandertyler 1:ec00f549a691 517
alexandertyler 1:ec00f549a691 518 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
alexandertyler 1:ec00f549a691 519 data[1] = (accel_bias_reg[0]) & 0xFF;
alexandertyler 1:ec00f549a691 520 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
alexandertyler 1:ec00f549a691 521 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
alexandertyler 1:ec00f549a691 522 data[3] = (accel_bias_reg[1]) & 0xFF;
alexandertyler 1:ec00f549a691 523 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
alexandertyler 1:ec00f549a691 524 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
alexandertyler 1:ec00f549a691 525 data[5] = (accel_bias_reg[2]) & 0xFF;
alexandertyler 1:ec00f549a691 526 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
alexandertyler 1:ec00f549a691 527
alexandertyler 1:ec00f549a691 528 // Push accelerometer biases to hardware registers
alexandertyler 1:ec00f549a691 529 // writeByte(MPU6050_ADDRESS, XA_OFFSET_H, data[0]);
alexandertyler 1:ec00f549a691 530 // writeByte(MPU6050_ADDRESS, XA_OFFSET_L_TC, data[1]);
alexandertyler 1:ec00f549a691 531 // writeByte(MPU6050_ADDRESS, YA_OFFSET_H, data[2]);
alexandertyler 1:ec00f549a691 532 // writeByte(MPU6050_ADDRESS, YA_OFFSET_L_TC, data[3]);
alexandertyler 1:ec00f549a691 533 // writeByte(MPU6050_ADDRESS, ZA_OFFSET_H, data[4]);
alexandertyler 1:ec00f549a691 534 // writeByte(MPU6050_ADDRESS, ZA_OFFSET_L_TC, data[5]);
alexandertyler 1:ec00f549a691 535
alexandertyler 1:ec00f549a691 536 // Output scaled accelerometer biases for manual subtraction in the main program
alexandertyler 1:ec00f549a691 537 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity;
alexandertyler 1:ec00f549a691 538 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity;
alexandertyler 1:ec00f549a691 539 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
alexandertyler 1:ec00f549a691 540 }
alexandertyler 1:ec00f549a691 541
alexandertyler 1:ec00f549a691 542
alexandertyler 1:ec00f549a691 543 // Accelerometer and gyroscope self test; check calibration wrt factory settings
alexandertyler 1:ec00f549a691 544 void MPU6050SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
alexandertyler 1:ec00f549a691 545 {
alexandertyler 1:ec00f549a691 546 uint8_t rawData[4] = {0, 0, 0, 0};
alexandertyler 1:ec00f549a691 547 uint8_t selfTest[6];
alexandertyler 1:ec00f549a691 548 float factoryTrim[6];
alexandertyler 1:ec00f549a691 549
alexandertyler 1:ec00f549a691 550 // Configure the accelerometer for self-test
alexandertyler 1:ec00f549a691 551 writeByte(MPU6050_ADDRESS, ACCEL_CONFIG, 0xF0); // Enable self test on all three axes and set accelerometer range to +/- 8 g
alexandertyler 1:ec00f549a691 552 writeByte(MPU6050_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
alexandertyler 1:ec00f549a691 553 wait(0.25); // Delay a while to let the device execute the self-test
alexandertyler 1:ec00f549a691 554 rawData[0] = readByte(MPU6050_ADDRESS, SELF_TEST_X); // X-axis self-test results
alexandertyler 1:ec00f549a691 555 rawData[1] = readByte(MPU6050_ADDRESS, SELF_TEST_Y); // Y-axis self-test results
alexandertyler 1:ec00f549a691 556 rawData[2] = readByte(MPU6050_ADDRESS, SELF_TEST_Z); // Z-axis self-test results
alexandertyler 1:ec00f549a691 557 rawData[3] = readByte(MPU6050_ADDRESS, SELF_TEST_A); // Mixed-axis self-test results
alexandertyler 1:ec00f549a691 558 // Extract the acceleration test results first
alexandertyler 1:ec00f549a691 559 selfTest[0] = (rawData[0] >> 3) | (rawData[3] & 0x30) >> 4 ; // XA_TEST result is a five-bit unsigned integer
alexandertyler 1:ec00f549a691 560 selfTest[1] = (rawData[1] >> 3) | (rawData[3] & 0x0C) >> 4 ; // YA_TEST result is a five-bit unsigned integer
alexandertyler 1:ec00f549a691 561 selfTest[2] = (rawData[2] >> 3) | (rawData[3] & 0x03) >> 4 ; // ZA_TEST result is a five-bit unsigned integer
alexandertyler 1:ec00f549a691 562 // Extract the gyration test results first
alexandertyler 1:ec00f549a691 563 selfTest[3] = rawData[0] & 0x1F ; // XG_TEST result is a five-bit unsigned integer
alexandertyler 1:ec00f549a691 564 selfTest[4] = rawData[1] & 0x1F ; // YG_TEST result is a five-bit unsigned integer
alexandertyler 1:ec00f549a691 565 selfTest[5] = rawData[2] & 0x1F ; // ZG_TEST result is a five-bit unsigned integer
alexandertyler 1:ec00f549a691 566 // Process results to allow final comparison with factory set values
alexandertyler 1:ec00f549a691 567 factoryTrim[0] = (4096.0f*0.34f)*(pow( (0.92f/0.34f) , ((selfTest[0] - 1.0f)/30.0f))); // FT[Xa] factory trim calculation
alexandertyler 1:ec00f549a691 568 factoryTrim[1] = (4096.0f*0.34f)*(pow( (0.92f/0.34f) , ((selfTest[1] - 1.0f)/30.0f))); // FT[Ya] factory trim calculation
alexandertyler 1:ec00f549a691 569 factoryTrim[2] = (4096.0f*0.34f)*(pow( (0.92f/0.34f) , ((selfTest[2] - 1.0f)/30.0f))); // FT[Za] factory trim calculation
alexandertyler 1:ec00f549a691 570 factoryTrim[3] = ( 25.0f*131.0f)*(pow( 1.046f , (selfTest[3] - 1.0f) )); // FT[Xg] factory trim calculation
alexandertyler 1:ec00f549a691 571 factoryTrim[4] = (-25.0f*131.0f)*(pow( 1.046f , (selfTest[4] - 1.0f) )); // FT[Yg] factory trim calculation
alexandertyler 1:ec00f549a691 572 factoryTrim[5] = ( 25.0f*131.0f)*(pow( 1.046f , (selfTest[5] - 1.0f) )); // FT[Zg] factory trim calculation
alexandertyler 1:ec00f549a691 573
alexandertyler 1:ec00f549a691 574 // Output self-test results and factory trim calculation if desired
alexandertyler 1:ec00f549a691 575 // Serial.println(selfTest[0]); Serial.println(selfTest[1]); Serial.println(selfTest[2]);
alexandertyler 1:ec00f549a691 576 // Serial.println(selfTest[3]); Serial.println(selfTest[4]); Serial.println(selfTest[5]);
alexandertyler 1:ec00f549a691 577 // Serial.println(factoryTrim[0]); Serial.println(factoryTrim[1]); Serial.println(factoryTrim[2]);
alexandertyler 1:ec00f549a691 578 // Serial.println(factoryTrim[3]); Serial.println(factoryTrim[4]); Serial.println(factoryTrim[5]);
alexandertyler 1:ec00f549a691 579
alexandertyler 1:ec00f549a691 580 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
alexandertyler 1:ec00f549a691 581 // To get to percent, must multiply by 100 and subtract result from 100
alexandertyler 1:ec00f549a691 582 for (int i = 0; i < 6; i++) {
alexandertyler 1:ec00f549a691 583 destination[i] = 100.0f + 100.0f*(selfTest[i] - factoryTrim[i])/factoryTrim[i]; // Report percent differences
alexandertyler 1:ec00f549a691 584 }
alexandertyler 1:ec00f549a691 585
alexandertyler 1:ec00f549a691 586 }
alexandertyler 1:ec00f549a691 587
alexandertyler 1:ec00f549a691 588
alexandertyler 1:ec00f549a691 589 // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
alexandertyler 1:ec00f549a691 590 // (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
alexandertyler 1:ec00f549a691 591 // which fuses acceleration and rotation rate to produce a quaternion-based estimate of relative
alexandertyler 1:ec00f549a691 592 // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
alexandertyler 1:ec00f549a691 593 // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
alexandertyler 1:ec00f549a691 594 // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
alexandertyler 1:ec00f549a691 595 void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz)
alexandertyler 1:ec00f549a691 596 {
alexandertyler 1:ec00f549a691 597 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
alexandertyler 1:ec00f549a691 598 float norm; // vector norm
alexandertyler 1:ec00f549a691 599 float f1, f2, f3; // objective funcyion elements
alexandertyler 1:ec00f549a691 600 float J_11or24, J_12or23, J_13or22, J_14or21, J_32, J_33; // objective function Jacobian elements
alexandertyler 1:ec00f549a691 601 float qDot1, qDot2, qDot3, qDot4;
alexandertyler 1:ec00f549a691 602 float hatDot1, hatDot2, hatDot3, hatDot4;
alexandertyler 1:ec00f549a691 603 float gerrx, gerry, gerrz, gbiasx, gbiasy, gbiasz; // gyro bias error
alexandertyler 1:ec00f549a691 604
alexandertyler 1:ec00f549a691 605 // Auxiliary variables to avoid repeated arithmetic
alexandertyler 1:ec00f549a691 606 float _halfq1 = 0.5f * q1;
alexandertyler 1:ec00f549a691 607 float _halfq2 = 0.5f * q2;
alexandertyler 1:ec00f549a691 608 float _halfq3 = 0.5f * q3;
alexandertyler 1:ec00f549a691 609 float _halfq4 = 0.5f * q4;
alexandertyler 1:ec00f549a691 610 float _2q1 = 2.0f * q1;
alexandertyler 1:ec00f549a691 611 float _2q2 = 2.0f * q2;
alexandertyler 1:ec00f549a691 612 float _2q3 = 2.0f * q3;
alexandertyler 1:ec00f549a691 613 float _2q4 = 2.0f * q4;
alexandertyler 1:ec00f549a691 614 // float _2q1q3 = 2.0f * q1 * q3;
alexandertyler 1:ec00f549a691 615 // float _2q3q4 = 2.0f * q3 * q4;
alexandertyler 1:ec00f549a691 616
alexandertyler 1:ec00f549a691 617 // Normalise accelerometer measurement
alexandertyler 1:ec00f549a691 618 norm = sqrt(ax * ax + ay * ay + az * az);
alexandertyler 1:ec00f549a691 619 if (norm == 0.0f) return; // handle NaN
alexandertyler 1:ec00f549a691 620 norm = 1.0f/norm;
alexandertyler 1:ec00f549a691 621 ax *= norm;
alexandertyler 1:ec00f549a691 622 ay *= norm;
alexandertyler 1:ec00f549a691 623 az *= norm;
alexandertyler 1:ec00f549a691 624
alexandertyler 1:ec00f549a691 625 // Compute the objective function and Jacobian
alexandertyler 1:ec00f549a691 626 f1 = _2q2 * q4 - _2q1 * q3 - ax;
alexandertyler 1:ec00f549a691 627 f2 = _2q1 * q2 + _2q3 * q4 - ay;
alexandertyler 1:ec00f549a691 628 f3 = 1.0f - _2q2 * q2 - _2q3 * q3 - az;
alexandertyler 1:ec00f549a691 629 J_11or24 = _2q3;
alexandertyler 1:ec00f549a691 630 J_12or23 = _2q4;
alexandertyler 1:ec00f549a691 631 J_13or22 = _2q1;
alexandertyler 1:ec00f549a691 632 J_14or21 = _2q2;
alexandertyler 1:ec00f549a691 633 J_32 = 2.0f * J_14or21;
alexandertyler 1:ec00f549a691 634 J_33 = 2.0f * J_11or24;
alexandertyler 1:ec00f549a691 635
alexandertyler 1:ec00f549a691 636 // Compute the gradient (matrix multiplication)
alexandertyler 1:ec00f549a691 637 hatDot1 = J_14or21 * f2 - J_11or24 * f1;
alexandertyler 1:ec00f549a691 638 hatDot2 = J_12or23 * f1 + J_13or22 * f2 - J_32 * f3;
alexandertyler 1:ec00f549a691 639 hatDot3 = J_12or23 * f2 - J_33 *f3 - J_13or22 * f1;
alexandertyler 1:ec00f549a691 640 hatDot4 = J_14or21 * f1 + J_11or24 * f2;
alexandertyler 1:ec00f549a691 641
alexandertyler 1:ec00f549a691 642 // Normalize the gradient
alexandertyler 1:ec00f549a691 643 norm = sqrt(hatDot1 * hatDot1 + hatDot2 * hatDot2 + hatDot3 * hatDot3 + hatDot4 * hatDot4);
alexandertyler 1:ec00f549a691 644 hatDot1 /= norm;
alexandertyler 1:ec00f549a691 645 hatDot2 /= norm;
alexandertyler 1:ec00f549a691 646 hatDot3 /= norm;
alexandertyler 1:ec00f549a691 647 hatDot4 /= norm;
alexandertyler 1:ec00f549a691 648
alexandertyler 1:ec00f549a691 649 // Compute estimated gyroscope biases
alexandertyler 1:ec00f549a691 650 gerrx = _2q1 * hatDot2 - _2q2 * hatDot1 - _2q3 * hatDot4 + _2q4 * hatDot3;
alexandertyler 1:ec00f549a691 651 gerry = _2q1 * hatDot3 + _2q2 * hatDot4 - _2q3 * hatDot1 - _2q4 * hatDot2;
alexandertyler 1:ec00f549a691 652 gerrz = _2q1 * hatDot4 - _2q2 * hatDot3 + _2q3 * hatDot2 - _2q4 * hatDot1;
alexandertyler 1:ec00f549a691 653
alexandertyler 1:ec00f549a691 654 // Compute and remove gyroscope biases
alexandertyler 1:ec00f549a691 655 gbiasx += gerrx * deltat * zeta;
alexandertyler 1:ec00f549a691 656 gbiasy += gerry * deltat * zeta;
alexandertyler 1:ec00f549a691 657 gbiasz += gerrz * deltat * zeta;
alexandertyler 1:ec00f549a691 658 // gx -= gbiasx;
alexandertyler 1:ec00f549a691 659 // gy -= gbiasy;
alexandertyler 1:ec00f549a691 660 // gz -= gbiasz;
alexandertyler 1:ec00f549a691 661
alexandertyler 1:ec00f549a691 662 // Compute the quaternion derivative
alexandertyler 1:ec00f549a691 663 qDot1 = -_halfq2 * gx - _halfq3 * gy - _halfq4 * gz;
alexandertyler 1:ec00f549a691 664 qDot2 = _halfq1 * gx + _halfq3 * gz - _halfq4 * gy;
alexandertyler 1:ec00f549a691 665 qDot3 = _halfq1 * gy - _halfq2 * gz + _halfq4 * gx;
alexandertyler 1:ec00f549a691 666 qDot4 = _halfq1 * gz + _halfq2 * gy - _halfq3 * gx;
alexandertyler 1:ec00f549a691 667
alexandertyler 1:ec00f549a691 668 // Compute then integrate estimated quaternion derivative
alexandertyler 1:ec00f549a691 669 q1 += (qDot1 -(beta * hatDot1)) * deltat;
alexandertyler 1:ec00f549a691 670 q2 += (qDot2 -(beta * hatDot2)) * deltat;
alexandertyler 1:ec00f549a691 671 q3 += (qDot3 -(beta * hatDot3)) * deltat;
alexandertyler 1:ec00f549a691 672 q4 += (qDot4 -(beta * hatDot4)) * deltat;
alexandertyler 1:ec00f549a691 673
alexandertyler 1:ec00f549a691 674 // Normalize the quaternion
alexandertyler 1:ec00f549a691 675 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
alexandertyler 1:ec00f549a691 676 norm = 1.0f/norm;
alexandertyler 1:ec00f549a691 677 q[0] = q1 * norm;
alexandertyler 1:ec00f549a691 678 q[1] = q2 * norm;
alexandertyler 1:ec00f549a691 679 q[2] = q3 * norm;
alexandertyler 1:ec00f549a691 680 q[3] = q4 * norm;
alexandertyler 1:ec00f549a691 681
alexandertyler 1:ec00f549a691 682 }
alexandertyler 1:ec00f549a691 683
alexandertyler 1:ec00f549a691 684
alexandertyler 1:ec00f549a691 685 };
alexandertyler 1:ec00f549a691 686 #endif