Александр Селифонов / MPU9250_Interface

temprary

MPU9250.cpp@2:a36510ff4272, 2020-01-27 (annotated)

Committer:
turumputum
Date:
Mon Jan 27 10:19:04 2020 +0000
Revision:
2:a36510ff4272
Parent:
1:e16407b5e24f 
turn off while(1) in sensor init

Who changed what in which revision?

UserRevisionLine numberNew contents of line
soulx 0:b502ea2d6ebb 1 #include "MPU9250.h"
soulx 0:b502ea2d6ebb 2
soulx 0:b502ea2d6ebb 3
dimavb 1:e16407b5e24f 4 MPU9250::MPU9250(I2C * _i2c, Serial * _pc, int address)
soulx 0:b502ea2d6ebb 5 {
soulx 0:b502ea2d6ebb 6 if(address == 0)
soulx 0:b502ea2d6ebb 7 MPU9250_ADDRESS = MPU9250_ADDRESS_68;
soulx 0:b502ea2d6ebb 8 else if(address == 1) MPU9250_ADDRESS = MPU9250_ADDRESS_69;
soulx 0:b502ea2d6ebb 9 else {
soulx 0:b502ea2d6ebb 10 printf("Wrong Address\n");
soulx 0:b502ea2d6ebb 11 while(1);
soulx 0:b502ea2d6ebb 12 }
dimavb 1:e16407b5e24f 13 i2c=_i2c;
dimavb 1:e16407b5e24f 14 pc=_pc;
dimavb 1:e16407b5e24f 15 pc->printf("MPU hello\n");
dimavb 1:e16407b5e24f 16 i2c->frequency(400000);
soulx 0:b502ea2d6ebb 17
soulx 0:b502ea2d6ebb 18 for(int i=0; i<=3; i++) {
soulx 0:b502ea2d6ebb 19 magCalibration[i] = 0;
soulx 0:b502ea2d6ebb 20 magbias[i] = 0;
soulx 0:b502ea2d6ebb 21 gyroBias[i] = 0;
soulx 0:b502ea2d6ebb 22 accelBias[i] = 0;
soulx 0:b502ea2d6ebb 23 }
soulx 0:b502ea2d6ebb 24 Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR
soulx 0:b502ea2d6ebb 25 }
soulx 0:b502ea2d6ebb 26
soulx 0:b502ea2d6ebb 27 void MPU9250::Start()
soulx 0:b502ea2d6ebb 28 {
soulx 0:b502ea2d6ebb 29 whoami = readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250
dimavb 1:e16407b5e24f 30 pc->printf("I AM 0x%x\n\r", whoami);
dimavb 1:e16407b5e24f 31 pc->printf("I SHOULD BE 0x71\n\r");
soulx 0:b502ea2d6ebb 32
soulx 0:b502ea2d6ebb 33 if (whoami == 0x71) { // WHO_AM_I should always be 0x68
dimavb 1:e16407b5e24f 34 pc->printf("MPU9250 WHO_AM_I is 0x%x\n\r", whoami);
dimavb 1:e16407b5e24f 35 pc->printf("MPU9250 is online...\n\r");
dimavb 1:e16407b5e24f 36 wait(0.1);
soulx 0:b502ea2d6ebb 37
soulx 0:b502ea2d6ebb 38 resetMPU9250(); // Reset registers to default in preparation for device calibration
soulx 0:b502ea2d6ebb 39 MPU9250SelfTest(); // Start by performing self test and reporting values
dimavb 1:e16407b5e24f 40 /*pc->printf("x-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[0]);
dimavb 1:e16407b5e24f 41 pc->printf("y-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[1]);
dimavb 1:e16407b5e24f 42 pc->printf("z-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[2]);
dimavb 1:e16407b5e24f 43 pc->printf("x-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[3]);
dimavb 1:e16407b5e24f 44 pc->printf("y-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[4]);
dimavb 1:e16407b5e24f 45 pc->printf("z-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[5]);*/
dimavb 1:e16407b5e24f 46
dimavb 1:e16407b5e24f 47 //calibrateMPU9250(); // Calibrate gyro and accelerometers, load biases in bias registers
dimavb 1:e16407b5e24f 48
dimavb 1:e16407b5e24f 49 /*pc->printf("x gyro bias = %f\n\r", gyroBias[0]);
dimavb 1:e16407b5e24f 50 pc->printf("y gyro bias = %f\n\r", gyroBias[1]);
dimavb 1:e16407b5e24f 51 pc->printf("z gyro bias = %f\n\r", gyroBias[2]);
dimavb 1:e16407b5e24f 52 pc->printf("x accel bias = %f\n\r", accelBias[0]);
dimavb 1:e16407b5e24f 53 pc->printf("y accel bias = %f\n\r", accelBias[1]);
dimavb 1:e16407b5e24f 54 pc->printf("z accel bias = %f\n\r", accelBias[2]);*/
dimavb 1:e16407b5e24f 55 wait(0.2);
soulx 0:b502ea2d6ebb 56 initMPU9250();
dimavb 1:e16407b5e24f 57 pc->printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
soulx 0:b502ea2d6ebb 58 initAK8963();
dimavb 1:e16407b5e24f 59 pc->printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer
soulx 0:b502ea2d6ebb 60
soulx 0:b502ea2d6ebb 61 whoami = readByte(AK8963_ADDRESS, WHO_AM_I_AK8963); // Read WHO_AM_I register for MPU-9250
dimavb 1:e16407b5e24f 62 pc->printf("I AM 0x%x\n\r", whoami);
dimavb 1:e16407b5e24f 63 pc->printf("I SHOULD BE 0x48\n\r");
soulx 0:b502ea2d6ebb 64 if(whoami != 0x48) {
soulx 0:b502ea2d6ebb 65 while(1);
soulx 0:b502ea2d6ebb 66 }
dimavb 1:e16407b5e24f 67 /*pc->printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale));
dimavb 1:e16407b5e24f 68 pc->printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale));
dimavb 1:e16407b5e24f 69 if(Mscale == 0) pc->printf("Magnetometer resolution = 14 bits\n\r");
dimavb 1:e16407b5e24f 70 if(Mscale == 1) pc->printf("Magnetometer resolution = 16 bits\n\r");
dimavb 1:e16407b5e24f 71 if(Mmode == 2) pc->printf("Magnetometer ODR = 8 Hz\n\r");
dimavb 1:e16407b5e24f 72 if(Mmode == 6) pc->printf("Magnetometer ODR = 100 Hz\n\r");*/
dimavb 1:e16407b5e24f 73 wait(0.1);
soulx 0:b502ea2d6ebb 74 } else {
dimavb 1:e16407b5e24f 75 pc->printf("Could not connect to MPU9250: \n\r");
dimavb 1:e16407b5e24f 76 pc->printf("%#x \n", whoami);
turumputum 2:a36510ff4272 77 //wait(5);
turumputum 2:a36510ff4272 78 //while(1) ; // Loop forever if communication doesn't happen
soulx 0:b502ea2d6ebb 79 }
soulx 0:b502ea2d6ebb 80
soulx 0:b502ea2d6ebb 81
soulx 0:b502ea2d6ebb 82 getAres(); // Get accelerometer sensitivity
soulx 0:b502ea2d6ebb 83 getGres(); // Get gyro sensitivity
soulx 0:b502ea2d6ebb 84 getMres(); // Get magnetometer sensitivity
dimavb 1:e16407b5e24f 85 /*pc->printf("Accelerometer sensitivity is %f LSB/g \n\r", 1.0f/aRes);
dimavb 1:e16407b5e24f 86 pc->printf("Gyroscope sensitivity is %f LSB/deg/s \n\r", 1.0f/gRes);
dimavb 1:e16407b5e24f 87 pc->printf("Magnetometer sensitivity is %f LSB/G \n\r", 1.0f/mRes);*/
soulx 0:b502ea2d6ebb 88
soulx 0:b502ea2d6ebb 89 MagCal();
soulx 0:b502ea2d6ebb 90 }
soulx 0:b502ea2d6ebb 91
soulx 0:b502ea2d6ebb 92 void MPU9250::ReadRawAccGyroMag()
soulx 0:b502ea2d6ebb 93 {
soulx 0:b502ea2d6ebb 94 // If intPin goes high, all data registers have new data
soulx 0:b502ea2d6ebb 95 if(readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt
soulx 0:b502ea2d6ebb 96
soulx 0:b502ea2d6ebb 97 readAccelData(); // Read the x/y/z adc values
soulx 0:b502ea2d6ebb 98 AccelXYZCal();
soulx 0:b502ea2d6ebb 99 // Now we'll calculate the accleration value into actual g's
soulx 0:b502ea2d6ebb 100 /*ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
soulx 0:b502ea2d6ebb 101 ay = (float)accelCount[1]*aRes - accelBias[1];
soulx 0:b502ea2d6ebb 102 az = (float)accelCount[2]*aRes - accelBias[2];*/
soulx 0:b502ea2d6ebb 103
soulx 0:b502ea2d6ebb 104 readGyroData(); // Read the x/y/z adc values
soulx 0:b502ea2d6ebb 105 GyroXYZCal();
soulx 0:b502ea2d6ebb 106 // Calculate the gyro value into actual degrees per second
soulx 0:b502ea2d6ebb 107 /*gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
soulx 0:b502ea2d6ebb 108 gy = (float)gyroCount[1]*gRes - gyroBias[1];
soulx 0:b502ea2d6ebb 109 gz = (float)gyroCount[2]*gRes - gyroBias[2];*/
soulx 0:b502ea2d6ebb 110
soulx 0:b502ea2d6ebb 111 readMagData(); // Read the x/y/z adc values
soulx 0:b502ea2d6ebb 112 MagXYZCal();
soulx 0:b502ea2d6ebb 113 /*mx = ((float)magCount[0]-xmin)*magCalibration[0] + magbias[0]; // get actual magnetometer value, this depends on scale being set
soulx 0:b502ea2d6ebb 114 my = ((float)magCount[1]-ymin)*magCalibration[1] + magbias[1];
soulx 0:b502ea2d6ebb 115 mz = ((float)magCount[2]-zmin)*magCalibration[2] + magbias[2];*/
soulx 0:b502ea2d6ebb 116 }
soulx 0:b502ea2d6ebb 117 }
soulx 0:b502ea2d6ebb 118
soulx 0:b502ea2d6ebb 119 void MPU9250::writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
soulx 0:b502ea2d6ebb 120 {
soulx 0:b502ea2d6ebb 121 char data_write[2];
soulx 0:b502ea2d6ebb 122 data_write[0] = subAddress;
soulx 0:b502ea2d6ebb 123 data_write[1] = data;
dimavb 1:e16407b5e24f 124 i2c->write(address, data_write, 2, 0);
soulx 0:b502ea2d6ebb 125 }
soulx 0:b502ea2d6ebb 126
soulx 0:b502ea2d6ebb 127 char MPU9250::readByte(uint8_t address, uint8_t subAddress)
soulx 0:b502ea2d6ebb 128 {
soulx 0:b502ea2d6ebb 129 char data[1]; // `data` will store the register data
soulx 0:b502ea2d6ebb 130 char data_write[1];
soulx 0:b502ea2d6ebb 131 data_write[0] = subAddress;
dimavb 1:e16407b5e24f 132 i2c->write(address, data_write, 1, 1); // no stop
dimavb 1:e16407b5e24f 133 i2c->read(address, data, 1, 0);
soulx 0:b502ea2d6ebb 134 return data[0];
soulx 0:b502ea2d6ebb 135 }
soulx 0:b502ea2d6ebb 136
soulx 0:b502ea2d6ebb 137 void MPU9250::readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
soulx 0:b502ea2d6ebb 138 {
soulx 0:b502ea2d6ebb 139 char data[14];
soulx 0:b502ea2d6ebb 140 char data_write[1];
soulx 0:b502ea2d6ebb 141 data_write[0] = subAddress;
dimavb 1:e16407b5e24f 142 i2c->write(address, data_write, 1, 1); // no stop
dimavb 1:e16407b5e24f 143 i2c->read(address, data, count, 0);
soulx 0:b502ea2d6ebb 144 for(int ii = 0; ii < count; ii++) {
soulx 0:b502ea2d6ebb 145 dest[ii] = data[ii];
soulx 0:b502ea2d6ebb 146 }
soulx 0:b502ea2d6ebb 147 }
soulx 0:b502ea2d6ebb 148
soulx 0:b502ea2d6ebb 149
soulx 0:b502ea2d6ebb 150 void MPU9250::setMres()
soulx 0:b502ea2d6ebb 151 {
soulx 0:b502ea2d6ebb 152 getMres();
soulx 0:b502ea2d6ebb 153 switch (Mscale) {
soulx 0:b502ea2d6ebb 154 // Possible magnetometer scales (and their register bit settings) are:
soulx 0:b502ea2d6ebb 155 // 14 bit resolution (0) and 16 bit resolution (1)
soulx 0:b502ea2d6ebb 156 case MFS_14BITS:
soulx 0:b502ea2d6ebb 157 mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss
soulx 0:b502ea2d6ebb 158 break;
soulx 0:b502ea2d6ebb 159 case MFS_16BITS:
soulx 0:b502ea2d6ebb 160 mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss
soulx 0:b502ea2d6ebb 161 break;
soulx 0:b502ea2d6ebb 162 }
soulx 0:b502ea2d6ebb 163 }
soulx 0:b502ea2d6ebb 164
soulx 0:b502ea2d6ebb 165
soulx 0:b502ea2d6ebb 166 void MPU9250::setGres()
soulx 0:b502ea2d6ebb 167 {
soulx 0:b502ea2d6ebb 168 getGres();
soulx 0:b502ea2d6ebb 169 switch (Gscale) {
soulx 0:b502ea2d6ebb 170 // Possible gyro scales (and their register bit settings) are:
soulx 0:b502ea2d6ebb 171 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
soulx 0:b502ea2d6ebb 172 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
soulx 0:b502ea2d6ebb 173 case GFS_250DPS:
soulx 0:b502ea2d6ebb 174 gRes = 250.0/32768.0;
soulx 0:b502ea2d6ebb 175 break;
soulx 0:b502ea2d6ebb 176 case GFS_500DPS:
soulx 0:b502ea2d6ebb 177 gRes = 500.0/32768.0;
soulx 0:b502ea2d6ebb 178 break;
soulx 0:b502ea2d6ebb 179 case GFS_1000DPS:
soulx 0:b502ea2d6ebb 180 gRes = 1000.0/32768.0;
soulx 0:b502ea2d6ebb 181 break;
soulx 0:b502ea2d6ebb 182 case GFS_2000DPS:
soulx 0:b502ea2d6ebb 183 gRes = 2000.0/32768.0;
soulx 0:b502ea2d6ebb 184 break;
soulx 0:b502ea2d6ebb 185 }
soulx 0:b502ea2d6ebb 186 }
soulx 0:b502ea2d6ebb 187
soulx 0:b502ea2d6ebb 188 void MPU9250::setAres()
soulx 0:b502ea2d6ebb 189 {
soulx 0:b502ea2d6ebb 190 getAres();
soulx 0:b502ea2d6ebb 191 switch (Ascale) {
soulx 0:b502ea2d6ebb 192 // Possible accelerometer scales (and their register bit settings) are:
soulx 0:b502ea2d6ebb 193 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
soulx 0:b502ea2d6ebb 194 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
soulx 0:b502ea2d6ebb 195 case AFS_2G:
soulx 0:b502ea2d6ebb 196 aRes = 2.0/32768.0;
soulx 0:b502ea2d6ebb 197 break;
soulx 0:b502ea2d6ebb 198 case AFS_4G:
soulx 0:b502ea2d6ebb 199 aRes = 4.0/32768.0;
soulx 0:b502ea2d6ebb 200 break;
soulx 0:b502ea2d6ebb 201 case AFS_8G:
soulx 0:b502ea2d6ebb 202 aRes = 8.0/32768.0;
soulx 0:b502ea2d6ebb 203 break;
soulx 0:b502ea2d6ebb 204 case AFS_16G:
soulx 0:b502ea2d6ebb 205 aRes = 16.0/32768.0;
soulx 0:b502ea2d6ebb 206 break;
soulx 0:b502ea2d6ebb 207 }
soulx 0:b502ea2d6ebb 208 }
soulx 0:b502ea2d6ebb 209
soulx 0:b502ea2d6ebb 210 void MPU9250::getMres()
soulx 0:b502ea2d6ebb 211 {
soulx 0:b502ea2d6ebb 212 Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution
soulx 0:b502ea2d6ebb 213 }
soulx 0:b502ea2d6ebb 214
soulx 0:b502ea2d6ebb 215
soulx 0:b502ea2d6ebb 216 void MPU9250::getGres()
soulx 0:b502ea2d6ebb 217 {
soulx 0:b502ea2d6ebb 218 Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS
soulx 0:b502ea2d6ebb 219 }
soulx 0:b502ea2d6ebb 220
soulx 0:b502ea2d6ebb 221 void MPU9250::getAres()
soulx 0:b502ea2d6ebb 222 {
dimavb 1:e16407b5e24f 223 Ascale = AFS_16G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G
soulx 0:b502ea2d6ebb 224 }
soulx 0:b502ea2d6ebb 225
soulx 0:b502ea2d6ebb 226 void MPU9250::MagCal()
soulx 0:b502ea2d6ebb 227 {
soulx 0:b502ea2d6ebb 228 printf("START scan mag\n\r\n\r\n\r");
soulx 0:b502ea2d6ebb 229
soulx 0:b502ea2d6ebb 230 //Assign random value before calibrate
soulx 0:b502ea2d6ebb 231 /*xmax = -4914.0f;
soulx 0:b502ea2d6ebb 232 xmin = 4914.0f;
soulx 0:b502ea2d6ebb 233
soulx 0:b502ea2d6ebb 234 ymax = -4914.0;
soulx 0:b502ea2d6ebb 235 ymin = 4914.0f;
soulx 0:b502ea2d6ebb 236
soulx 0:b502ea2d6ebb 237 zmax = -4914.0;
soulx 0:b502ea2d6ebb 238 zmin = 4914.0f;
soulx 0:b502ea2d6ebb 239
soulx 0:b502ea2d6ebb 240 change=false;
soulx 0:b502ea2d6ebb 241
soulx 0:b502ea2d6ebb 242 while(1) {
soulx 0:b502ea2d6ebb 243 readMagData(magCount);
soulx 0:b502ea2d6ebb 244
soulx 0:b502ea2d6ebb 245 if(magCount[0]<xmin) {
soulx 0:b502ea2d6ebb 246 xmin = magCount[0];
soulx 0:b502ea2d6ebb 247 change = true;
soulx 0:b502ea2d6ebb 248 }
soulx 0:b502ea2d6ebb 249 if(magCount[0]>xmax) {
soulx 0:b502ea2d6ebb 250 xmax = magCount[0];
soulx 0:b502ea2d6ebb 251 change = true;
soulx 0:b502ea2d6ebb 252 }
soulx 0:b502ea2d6ebb 253
soulx 0:b502ea2d6ebb 254 if(magCount[1]<ymin) {
soulx 0:b502ea2d6ebb 255 ymin = magCount[1];
soulx 0:b502ea2d6ebb 256 change = true;
soulx 0:b502ea2d6ebb 257 }
soulx 0:b502ea2d6ebb 258 if(magCount[1]>ymax) {
soulx 0:b502ea2d6ebb 259 ymax = magCount[1];
soulx 0:b502ea2d6ebb 260 change = true;
soulx 0:b502ea2d6ebb 261 }
soulx 0:b502ea2d6ebb 262
soulx 0:b502ea2d6ebb 263
soulx 0:b502ea2d6ebb 264 if(magCount[2]<zmin) {
soulx 0:b502ea2d6ebb 265 zmin = magCount[2];
soulx 0:b502ea2d6ebb 266 change = true;
soulx 0:b502ea2d6ebb 267 }
soulx 0:b502ea2d6ebb 268 if(magCount[2]>zmax) {
soulx 0:b502ea2d6ebb 269 zmax = magCount[2];
soulx 0:b502ea2d6ebb 270 change = true;
soulx 0:b502ea2d6ebb 271 }
soulx 0:b502ea2d6ebb 272
soulx 0:b502ea2d6ebb 273 if(change==true) {
soulx 0:b502ea2d6ebb 274 printf("Mx Max= %f Min= %f\n\r",xmax,xmin);
soulx 0:b502ea2d6ebb 275 printf("My Max= %f Min= %f\n\r",ymax,ymin);
soulx 0:b502ea2d6ebb 276 printf("Mz Max= %f Min= %f\n\r",zmax,zmin);
soulx 0:b502ea2d6ebb 277 change=false;
soulx 0:b502ea2d6ebb 278 }*/
soulx 0:b502ea2d6ebb 279
soulx 0:b502ea2d6ebb 280 //Out of Calibration loop
soulx 0:b502ea2d6ebb 281 /*if(button==1) {
soulx 0:b502ea2d6ebb 282 while(button==1);
soulx 0:b502ea2d6ebb 283 break;
soulx 0:b502ea2d6ebb 284 }*/
soulx 0:b502ea2d6ebb 285 //}
soulx 0:b502ea2d6ebb 286
soulx 0:b502ea2d6ebb 287
soulx 0:b502ea2d6ebb 288 xmax = 188.000000;
soulx 0:b502ea2d6ebb 289 xmin = -316.000000;
soulx 0:b502ea2d6ebb 290 ymax = 485.000000;
soulx 0:b502ea2d6ebb 291 ymin = -26.000000;
soulx 0:b502ea2d6ebb 292 zmax = 165.000000;
soulx 0:b502ea2d6ebb 293 xmin = -230.000000;
soulx 0:b502ea2d6ebb 294
soulx 0:b502ea2d6ebb 295 magbias[0] = -1.0;
soulx 0:b502ea2d6ebb 296 magbias[1] = -1.0;
soulx 0:b502ea2d6ebb 297 magbias[2] = -1.0;
soulx 0:b502ea2d6ebb 298
soulx 0:b502ea2d6ebb 299 magCalibration[0] = 2.0f / (xmax -xmin);
soulx 0:b502ea2d6ebb 300 magCalibration[1] = 2.0f / (ymax -ymin);
soulx 0:b502ea2d6ebb 301 magCalibration[2] = 2.0f / (zmax -zmin);
soulx 0:b502ea2d6ebb 302
soulx 0:b502ea2d6ebb 303 printf("mag[0] %f",magbias[0]);
soulx 0:b502ea2d6ebb 304 printf("mag[1] %f",magbias[1]);
soulx 0:b502ea2d6ebb 305 printf("mag[2] %f\n\r",magbias[2]);
soulx 0:b502ea2d6ebb 306 }
soulx 0:b502ea2d6ebb 307
soulx 0:b502ea2d6ebb 308 void MPU9250::AccelXYZCal()
soulx 0:b502ea2d6ebb 309 {
soulx 0:b502ea2d6ebb 310 ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
soulx 0:b502ea2d6ebb 311 ay = (float)accelCount[1]*aRes - accelBias[1];
soulx 0:b502ea2d6ebb 312 az = (float)accelCount[2]*aRes - accelBias[2];
soulx 0:b502ea2d6ebb 313 }
soulx 0:b502ea2d6ebb 314
soulx 0:b502ea2d6ebb 315 void MPU9250::GyroXYZCal()
soulx 0:b502ea2d6ebb 316 {
soulx 0:b502ea2d6ebb 317 gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
soulx 0:b502ea2d6ebb 318 gy = (float)gyroCount[1]*gRes - gyroBias[1];
soulx 0:b502ea2d6ebb 319 gz = (float)gyroCount[2]*gRes - gyroBias[2];
soulx 0:b502ea2d6ebb 320 }
soulx 0:b502ea2d6ebb 321
soulx 0:b502ea2d6ebb 322 void MPU9250::MagXYZCal()
soulx 0:b502ea2d6ebb 323 {
soulx 0:b502ea2d6ebb 324 mx = ((float)magCount[0]-xmin)*magCalibration[0] + magbias[0]; // get actual magnetometer value, this depends on scale being set
soulx 0:b502ea2d6ebb 325 my = ((float)magCount[1]-ymin)*magCalibration[1] + magbias[1];
soulx 0:b502ea2d6ebb 326 mz = ((float)magCount[2]-zmin)*magCalibration[2] + magbias[2];
soulx 0:b502ea2d6ebb 327 }
soulx 0:b502ea2d6ebb 328
soulx 0:b502ea2d6ebb 329
soulx 0:b502ea2d6ebb 330 void MPU9250::readAccelData()
soulx 0:b502ea2d6ebb 331 {
soulx 0:b502ea2d6ebb 332 float destination[3] = {0,0,0};
soulx 0:b502ea2d6ebb 333 uint8_t rawData[6]; // x/y/z accel register data stored here
soulx 0:b502ea2d6ebb 334 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
soulx 0:b502ea2d6ebb 335 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
soulx 0:b502ea2d6ebb 336 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
soulx 0:b502ea2d6ebb 337 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
soulx 0:b502ea2d6ebb 338
soulx 0:b502ea2d6ebb 339 for(int i=0; i<=2; i++)
soulx 0:b502ea2d6ebb 340 accelCount[i] = (float)destination[i];
soulx 0:b502ea2d6ebb 341 }
soulx 0:b502ea2d6ebb 342
soulx 0:b502ea2d6ebb 343 void MPU9250::readGyroData()
soulx 0:b502ea2d6ebb 344 {
soulx 0:b502ea2d6ebb 345 float destination[3] = {0,0,0};
soulx 0:b502ea2d6ebb 346 uint8_t rawData[6]; // x/y/z gyro register data stored here
soulx 0:b502ea2d6ebb 347 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
soulx 0:b502ea2d6ebb 348 destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
soulx 0:b502ea2d6ebb 349 destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
soulx 0:b502ea2d6ebb 350 destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
soulx 0:b502ea2d6ebb 351
soulx 0:b502ea2d6ebb 352 for(int i=0; i<=2; i++)
soulx 0:b502ea2d6ebb 353 gyroCount[i] = (float)destination[i];
soulx 0:b502ea2d6ebb 354 }
soulx 0:b502ea2d6ebb 355
soulx 0:b502ea2d6ebb 356 void MPU9250::readMagData()
soulx 0:b502ea2d6ebb 357 {
soulx 0:b502ea2d6ebb 358 float destination[3] = {0,0,0};
soulx 0:b502ea2d6ebb 359 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
soulx 0:b502ea2d6ebb 360 if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set
soulx 0:b502ea2d6ebb 361 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
soulx 0:b502ea2d6ebb 362 uint8_t c = rawData[6]; // End data read by reading ST2 register
soulx 0:b502ea2d6ebb 363 if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data
soulx 0:b502ea2d6ebb 364 destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value
soulx 0:b502ea2d6ebb 365 destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian
soulx 0:b502ea2d6ebb 366 destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ;
soulx 0:b502ea2d6ebb 367 }
soulx 0:b502ea2d6ebb 368 }
soulx 0:b502ea2d6ebb 369
soulx 0:b502ea2d6ebb 370 for(int i=0; i<=2; i++)
soulx 0:b502ea2d6ebb 371 magCount[i] = (float)destination[i];
soulx 0:b502ea2d6ebb 372 }
soulx 0:b502ea2d6ebb 373
soulx 0:b502ea2d6ebb 374 void MPU9250::readTempData()
soulx 0:b502ea2d6ebb 375 {
soulx 0:b502ea2d6ebb 376 int16_t destination;
soulx 0:b502ea2d6ebb 377 uint8_t rawData[2]; // x/y/z gyro register data stored here
soulx 0:b502ea2d6ebb 378 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
soulx 0:b502ea2d6ebb 379 destination = (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
soulx 0:b502ea2d6ebb 380 destination = ((float) destination) / 333.87f + 21.0f;
soulx 0:b502ea2d6ebb 381 temperature = destination;
soulx 0:b502ea2d6ebb 382 }
soulx 0:b502ea2d6ebb 383
soulx 0:b502ea2d6ebb 384
soulx 0:b502ea2d6ebb 385 void MPU9250::resetMPU9250()
soulx 0:b502ea2d6ebb 386 {
soulx 0:b502ea2d6ebb 387 // reset device
soulx 0:b502ea2d6ebb 388 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
soulx 0:b502ea2d6ebb 389 wait(0.1);
soulx 0:b502ea2d6ebb 390 }
soulx 0:b502ea2d6ebb 391
soulx 0:b502ea2d6ebb 392 void MPU9250::initAK8963()
soulx 0:b502ea2d6ebb 393 {
soulx 0:b502ea2d6ebb 394 float destination[3] = {0,0,0};
soulx 0:b502ea2d6ebb 395 // First extract the factory calibration for each magnetometer axis
soulx 0:b502ea2d6ebb 396 uint8_t rawData[3]; // x/y/z gyro calibration data stored here
soulx 0:b502ea2d6ebb 397 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
soulx 0:b502ea2d6ebb 398 wait(0.01);
soulx 0:b502ea2d6ebb 399 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
soulx 0:b502ea2d6ebb 400 wait(0.01);
soulx 0:b502ea2d6ebb 401 readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
soulx 0:b502ea2d6ebb 402 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
soulx 0:b502ea2d6ebb 403 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
soulx 0:b502ea2d6ebb 404 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
soulx 0:b502ea2d6ebb 405 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
soulx 0:b502ea2d6ebb 406 wait(0.01);
soulx 0:b502ea2d6ebb 407 // Configure the magnetometer for continuous read and highest resolution
soulx 0:b502ea2d6ebb 408 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
soulx 0:b502ea2d6ebb 409 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
soulx 0:b502ea2d6ebb 410 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
soulx 0:b502ea2d6ebb 411 wait(0.01);
soulx 0:b502ea2d6ebb 412
soulx 0:b502ea2d6ebb 413 for(int i=0; i<=2; i++)
soulx 0:b502ea2d6ebb 414 magCalibration[i] = destination[i];
soulx 0:b502ea2d6ebb 415 }
soulx 0:b502ea2d6ebb 416
soulx 0:b502ea2d6ebb 417
soulx 0:b502ea2d6ebb 418 void MPU9250::initMPU9250()
soulx 0:b502ea2d6ebb 419 {
soulx 0:b502ea2d6ebb 420 // Initialize MPU9250 device
soulx 0:b502ea2d6ebb 421 // wake up device
soulx 0:b502ea2d6ebb 422 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
soulx 0:b502ea2d6ebb 423 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
soulx 0:b502ea2d6ebb 424
soulx 0:b502ea2d6ebb 425 // get stable time source
soulx 0:b502ea2d6ebb 426 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
soulx 0:b502ea2d6ebb 427
soulx 0:b502ea2d6ebb 428 // Configure Gyro and Accelerometer
soulx 0:b502ea2d6ebb 429 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
soulx 0:b502ea2d6ebb 430 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
soulx 0:b502ea2d6ebb 431 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
soulx 0:b502ea2d6ebb 432 writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
soulx 0:b502ea2d6ebb 433
soulx 0:b502ea2d6ebb 434 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
soulx 0:b502ea2d6ebb 435 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
soulx 0:b502ea2d6ebb 436
soulx 0:b502ea2d6ebb 437 // Set gyroscope full scale range
soulx 0:b502ea2d6ebb 438 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
soulx 0:b502ea2d6ebb 439 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
soulx 0:b502ea2d6ebb 440 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
soulx 0:b502ea2d6ebb 441 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
soulx 0:b502ea2d6ebb 442 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
soulx 0:b502ea2d6ebb 443
soulx 0:b502ea2d6ebb 444 // Set accelerometer configuration
soulx 0:b502ea2d6ebb 445 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
soulx 0:b502ea2d6ebb 446 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
soulx 0:b502ea2d6ebb 447 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
soulx 0:b502ea2d6ebb 448 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
soulx 0:b502ea2d6ebb 449
soulx 0:b502ea2d6ebb 450 // Set accelerometer sample rate configuration
soulx 0:b502ea2d6ebb 451 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
soulx 0:b502ea2d6ebb 452 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
soulx 0:b502ea2d6ebb 453 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
soulx 0:b502ea2d6ebb 454 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
soulx 0:b502ea2d6ebb 455 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
soulx 0:b502ea2d6ebb 456
soulx 0:b502ea2d6ebb 457 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
soulx 0:b502ea2d6ebb 458 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
soulx 0:b502ea2d6ebb 459
soulx 0:b502ea2d6ebb 460 // Configure Interrupts and Bypass Enable
soulx 0:b502ea2d6ebb 461 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
soulx 0:b502ea2d6ebb 462 // can join the I2C bus and all can be controlled by the Arduino as master
soulx 0:b502ea2d6ebb 463 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
soulx 0:b502ea2d6ebb 464 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
soulx 0:b502ea2d6ebb 465 }
soulx 0:b502ea2d6ebb 466
soulx 0:b502ea2d6ebb 467 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average
soulx 0:b502ea2d6ebb 468 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers.
soulx 0:b502ea2d6ebb 469 void MPU9250::calibrateMPU9250()
soulx 0:b502ea2d6ebb 470 {
soulx 0:b502ea2d6ebb 471 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data
soulx 0:b502ea2d6ebb 472 uint16_t ii, packet_count, fifo_count;
soulx 0:b502ea2d6ebb 473 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};
soulx 0:b502ea2d6ebb 474
soulx 0:b502ea2d6ebb 475 // reset device, reset all registers, clear gyro and accelerometer bias registers
soulx 0:b502ea2d6ebb 476 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
soulx 0:b502ea2d6ebb 477 wait(0.1);
soulx 0:b502ea2d6ebb 478
soulx 0:b502ea2d6ebb 479 // get stable time source
soulx 0:b502ea2d6ebb 480 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
soulx 0:b502ea2d6ebb 481 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
soulx 0:b502ea2d6ebb 482 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
soulx 0:b502ea2d6ebb 483 wait(0.2);
soulx 0:b502ea2d6ebb 484
soulx 0:b502ea2d6ebb 485 // Configure device for bias calculation
soulx 0:b502ea2d6ebb 486 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
soulx 0:b502ea2d6ebb 487 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
soulx 0:b502ea2d6ebb 488 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
soulx 0:b502ea2d6ebb 489 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
soulx 0:b502ea2d6ebb 490 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
soulx 0:b502ea2d6ebb 491 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
soulx 0:b502ea2d6ebb 492 wait(0.015);
soulx 0:b502ea2d6ebb 493
soulx 0:b502ea2d6ebb 494 // Configure MPU9250 gyro and accelerometer for bias calculation
soulx 0:b502ea2d6ebb 495 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
soulx 0:b502ea2d6ebb 496 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
soulx 0:b502ea2d6ebb 497 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
soulx 0:b502ea2d6ebb 498 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity
soulx 0:b502ea2d6ebb 499
soulx 0:b502ea2d6ebb 500 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec
soulx 0:b502ea2d6ebb 501 uint16_t accelsensitivity = 16384; // = 16384 LSB/g
soulx 0:b502ea2d6ebb 502
soulx 0:b502ea2d6ebb 503 // Configure FIFO to capture accelerometer and gyro data for bias calculation
soulx 0:b502ea2d6ebb 504 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
soulx 0:b502ea2d6ebb 505 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
soulx 0:b502ea2d6ebb 506 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
soulx 0:b502ea2d6ebb 507
soulx 0:b502ea2d6ebb 508 // At end of sample accumulation, turn off FIFO sensor read
soulx 0:b502ea2d6ebb 509 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
soulx 0:b502ea2d6ebb 510 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count
soulx 0:b502ea2d6ebb 511 fifo_count = ((uint16_t)data[0] << 8) | data[1];
soulx 0:b502ea2d6ebb 512 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging
soulx 0:b502ea2d6ebb 513
soulx 0:b502ea2d6ebb 514 for (ii = 0; ii < packet_count; ii++) {
soulx 0:b502ea2d6ebb 515 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
soulx 0:b502ea2d6ebb 516 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging
soulx 0:b502ea2d6ebb 517 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO
soulx 0:b502ea2d6ebb 518 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ;
soulx 0:b502ea2d6ebb 519 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
soulx 0:b502ea2d6ebb 520 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ;
soulx 0:b502ea2d6ebb 521 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ;
soulx 0:b502ea2d6ebb 522 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;
soulx 0:b502ea2d6ebb 523
soulx 0:b502ea2d6ebb 524 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
soulx 0:b502ea2d6ebb 525 accel_bias[1] += (int32_t) accel_temp[1];
soulx 0:b502ea2d6ebb 526 accel_bias[2] += (int32_t) accel_temp[2];
soulx 0:b502ea2d6ebb 527 gyro_bias[0] += (int32_t) gyro_temp[0];
soulx 0:b502ea2d6ebb 528 gyro_bias[1] += (int32_t) gyro_temp[1];
soulx 0:b502ea2d6ebb 529 gyro_bias[2] += (int32_t) gyro_temp[2];
soulx 0:b502ea2d6ebb 530
soulx 0:b502ea2d6ebb 531 }
soulx 0:b502ea2d6ebb 532 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases
soulx 0:b502ea2d6ebb 533 accel_bias[1] /= (int32_t) packet_count;
soulx 0:b502ea2d6ebb 534 accel_bias[2] /= (int32_t) packet_count;
soulx 0:b502ea2d6ebb 535 gyro_bias[0] /= (int32_t) packet_count;
soulx 0:b502ea2d6ebb 536 gyro_bias[1] /= (int32_t) packet_count;
soulx 0:b502ea2d6ebb 537 gyro_bias[2] /= (int32_t) packet_count;
soulx 0:b502ea2d6ebb 538
soulx 0:b502ea2d6ebb 539 if(accel_bias[2] > 0L) {
soulx 0:b502ea2d6ebb 540 accel_bias[2] -= (int32_t) accelsensitivity; // Remove gravity from the z-axis accelerometer bias calculation
soulx 0:b502ea2d6ebb 541 } else {
soulx 0:b502ea2d6ebb 542 accel_bias[2] += (int32_t) accelsensitivity;
soulx 0:b502ea2d6ebb 543 }
soulx 0:b502ea2d6ebb 544
soulx 0:b502ea2d6ebb 545 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup
soulx 0:b502ea2d6ebb 546 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
soulx 0:b502ea2d6ebb 547 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases
soulx 0:b502ea2d6ebb 548 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF;
soulx 0:b502ea2d6ebb 549 data[3] = (-gyro_bias[1]/4) & 0xFF;
soulx 0:b502ea2d6ebb 550 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF;
soulx 0:b502ea2d6ebb 551 data[5] = (-gyro_bias[2]/4) & 0xFF;
soulx 0:b502ea2d6ebb 552
soulx 0:b502ea2d6ebb 553 /// Push gyro biases to hardware registers
soulx 0:b502ea2d6ebb 554 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
soulx 0:b502ea2d6ebb 555 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
soulx 0:b502ea2d6ebb 556 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
soulx 0:b502ea2d6ebb 557 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
soulx 0:b502ea2d6ebb 558 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
soulx 0:b502ea2d6ebb 559 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);
soulx 0:b502ea2d6ebb 560 */
soulx 0:b502ea2d6ebb 561 gyroBias[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction
soulx 0:b502ea2d6ebb 562 gyroBias[1] = (float) gyro_bias[1]/(float) gyrosensitivity;
soulx 0:b502ea2d6ebb 563 gyroBias[2] = (float) gyro_bias[2]/(float) gyrosensitivity;
soulx 0:b502ea2d6ebb 564
soulx 0:b502ea2d6ebb 565 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain
soulx 0:b502ea2d6ebb 566 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold
soulx 0:b502ea2d6ebb 567 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature
soulx 0:b502ea2d6ebb 568 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that
soulx 0:b502ea2d6ebb 569 // the accelerometer biases calculated above must be divided by 8.
soulx 0:b502ea2d6ebb 570
soulx 0:b502ea2d6ebb 571 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases
soulx 0:b502ea2d6ebb 572 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
soulx 0:b502ea2d6ebb 573 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
soulx 0:b502ea2d6ebb 574 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
soulx 0:b502ea2d6ebb 575 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
soulx 0:b502ea2d6ebb 576 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]);
soulx 0:b502ea2d6ebb 577 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1];
soulx 0:b502ea2d6ebb 578
soulx 0:b502ea2d6ebb 579 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers
soulx 0:b502ea2d6ebb 580 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis
soulx 0:b502ea2d6ebb 581
soulx 0:b502ea2d6ebb 582 for(ii = 0; ii < 3; ii++) {
soulx 0:b502ea2d6ebb 583 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit
soulx 0:b502ea2d6ebb 584 }
soulx 0:b502ea2d6ebb 585
soulx 0:b502ea2d6ebb 586 // Construct total accelerometer bias, including calculated average accelerometer bias from above
soulx 0:b502ea2d6ebb 587 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale)
soulx 0:b502ea2d6ebb 588 accel_bias_reg[1] -= (accel_bias[1]/8);
soulx 0:b502ea2d6ebb 589 accel_bias_reg[2] -= (accel_bias[2]/8);
soulx 0:b502ea2d6ebb 590
soulx 0:b502ea2d6ebb 591 data[0] = (accel_bias_reg[0] >> 8) & 0xFF;
soulx 0:b502ea2d6ebb 592 data[1] = (accel_bias_reg[0]) & 0xFF;
soulx 0:b502ea2d6ebb 593 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers
soulx 0:b502ea2d6ebb 594 data[2] = (accel_bias_reg[1] >> 8) & 0xFF;
soulx 0:b502ea2d6ebb 595 data[3] = (accel_bias_reg[1]) & 0xFF;
soulx 0:b502ea2d6ebb 596 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers
soulx 0:b502ea2d6ebb 597 data[4] = (accel_bias_reg[2] >> 8) & 0xFF;
soulx 0:b502ea2d6ebb 598 data[5] = (accel_bias_reg[2]) & 0xFF;
soulx 0:b502ea2d6ebb 599 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers
soulx 0:b502ea2d6ebb 600
soulx 0:b502ea2d6ebb 601 // Apparently this is not working for the acceleration biases in the MPU-9250
soulx 0:b502ea2d6ebb 602 // Are we handling the temperature correction bit properly?
soulx 0:b502ea2d6ebb 603 // Push accelerometer biases to hardware registers
soulx 0:b502ea2d6ebb 604 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
soulx 0:b502ea2d6ebb 605 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
soulx 0:b502ea2d6ebb 606 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
soulx 0:b502ea2d6ebb 607 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
soulx 0:b502ea2d6ebb 608 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
soulx 0:b502ea2d6ebb 609 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);
soulx 0:b502ea2d6ebb 610 */
soulx 0:b502ea2d6ebb 611 // Output scaled accelerometer biases for manual subtraction in the main program
soulx 0:b502ea2d6ebb 612 accelBias[0] = (float)accel_bias[0]/(float)accelsensitivity;
soulx 0:b502ea2d6ebb 613 accelBias[1] = (float)accel_bias[1]/(float)accelsensitivity;
soulx 0:b502ea2d6ebb 614 accelBias[2] = (float)accel_bias[2]/(float)accelsensitivity;
soulx 0:b502ea2d6ebb 615 }
soulx 0:b502ea2d6ebb 616
soulx 0:b502ea2d6ebb 617
soulx 0:b502ea2d6ebb 618 // Accelerometer and gyroscope self test; check calibration wrt factory settings
soulx 0:b502ea2d6ebb 619 void MPU9250::MPU9250SelfTest() // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
soulx 0:b502ea2d6ebb 620 {
soulx 0:b502ea2d6ebb 621 //float destination[6] = {0,0,0,0,0,0};
soulx 0:b502ea2d6ebb 622 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
soulx 0:b502ea2d6ebb 623 uint8_t selfTest[6];
soulx 0:b502ea2d6ebb 624 int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3];
soulx 0:b502ea2d6ebb 625 float factoryTrim[6];
soulx 0:b502ea2d6ebb 626 uint8_t FS = 0;
soulx 0:b502ea2d6ebb 627
soulx 0:b502ea2d6ebb 628 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
soulx 0:b502ea2d6ebb 629 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
soulx 0:b502ea2d6ebb 630 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
soulx 0:b502ea2d6ebb 631 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
soulx 0:b502ea2d6ebb 632 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
soulx 0:b502ea2d6ebb 633
soulx 0:b502ea2d6ebb 634 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
soulx 0:b502ea2d6ebb 635
soulx 0:b502ea2d6ebb 636 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
soulx 0:b502ea2d6ebb 637 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
soulx 0:b502ea2d6ebb 638 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
soulx 0:b502ea2d6ebb 639 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
soulx 0:b502ea2d6ebb 640
soulx 0:b502ea2d6ebb 641 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
soulx 0:b502ea2d6ebb 642 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
soulx 0:b502ea2d6ebb 643 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
soulx 0:b502ea2d6ebb 644 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
soulx 0:b502ea2d6ebb 645 }
soulx 0:b502ea2d6ebb 646
soulx 0:b502ea2d6ebb 647 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
soulx 0:b502ea2d6ebb 648 aAvg[ii] /= 200;
soulx 0:b502ea2d6ebb 649 gAvg[ii] /= 200;
soulx 0:b502ea2d6ebb 650 }
soulx 0:b502ea2d6ebb 651
soulx 0:b502ea2d6ebb 652 // Configure the accelerometer for self-test
soulx 0:b502ea2d6ebb 653 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
soulx 0:b502ea2d6ebb 654 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
soulx 0:b502ea2d6ebb 655 //delay(25); // Delay a while to let the device stabilize
soulx 0:b502ea2d6ebb 656
soulx 0:b502ea2d6ebb 657 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
soulx 0:b502ea2d6ebb 658
soulx 0:b502ea2d6ebb 659 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
soulx 0:b502ea2d6ebb 660 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
soulx 0:b502ea2d6ebb 661 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
soulx 0:b502ea2d6ebb 662 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
soulx 0:b502ea2d6ebb 663
soulx 0:b502ea2d6ebb 664 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
soulx 0:b502ea2d6ebb 665 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
soulx 0:b502ea2d6ebb 666 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
soulx 0:b502ea2d6ebb 667 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
soulx 0:b502ea2d6ebb 668 }
soulx 0:b502ea2d6ebb 669
soulx 0:b502ea2d6ebb 670 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
soulx 0:b502ea2d6ebb 671 aSTAvg[ii] /= 200;
soulx 0:b502ea2d6ebb 672 gSTAvg[ii] /= 200;
soulx 0:b502ea2d6ebb 673 }
soulx 0:b502ea2d6ebb 674
soulx 0:b502ea2d6ebb 675 // Configure the gyro and accelerometer for normal operation
soulx 0:b502ea2d6ebb 676 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
soulx 0:b502ea2d6ebb 677 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
soulx 0:b502ea2d6ebb 678 //delay(25); // Delay a while to let the device stabilize
soulx 0:b502ea2d6ebb 679
soulx 0:b502ea2d6ebb 680 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
soulx 0:b502ea2d6ebb 681 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
soulx 0:b502ea2d6ebb 682 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
soulx 0:b502ea2d6ebb 683 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
soulx 0:b502ea2d6ebb 684 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
soulx 0:b502ea2d6ebb 685 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
soulx 0:b502ea2d6ebb 686 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
soulx 0:b502ea2d6ebb 687
soulx 0:b502ea2d6ebb 688 // Retrieve factory self-test value from self-test code reads
soulx 0:b502ea2d6ebb 689 factoryTrim[0] = (float)(2620/1<<FS)*(pow( (float)1.01 , ((float)selfTest[0] - (float)1.0) )); // FT[Xa] factory trim calculation
soulx 0:b502ea2d6ebb 690 factoryTrim[1] = (float)(2620/1<<FS)*(pow( (float)1.01 , ((float)selfTest[1] - (float)1.0) )); // FT[Ya] factory trim calculation
soulx 0:b502ea2d6ebb 691 factoryTrim[2] = (float)(2620/1<<FS)*(pow( (float)1.01 , ((float)selfTest[2] - (float)1.0) )); // FT[Za] factory trim calculation
soulx 0:b502ea2d6ebb 692 factoryTrim[3] = (float)(2620/1<<FS)*(pow( (float)1.01 , ((float)selfTest[3] - (float)1.0) )); // FT[Xg] factory trim calculation
soulx 0:b502ea2d6ebb 693 factoryTrim[4] = (float)(2620/1<<FS)*(pow( (float)1.01 , ((float)selfTest[4] - (float)1.0) )); // FT[Yg] factory trim calculation
soulx 0:b502ea2d6ebb 694 factoryTrim[5] = (float)(2620/1<<FS)*(pow( (float)1.01 , ((float)selfTest[5] - (float)1.0) )); // FT[Zg] factory trim calculation
soulx 0:b502ea2d6ebb 695
soulx 0:b502ea2d6ebb 696 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
soulx 0:b502ea2d6ebb 697 // To get percent, must multiply by 100
soulx 0:b502ea2d6ebb 698 for (int i = 0; i < 3; i++) {
soulx 0:b502ea2d6ebb 699 SelfTest[i] = (float)100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences
soulx 0:b502ea2d6ebb 700 SelfTest[i+3] = (float)100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences
soulx 0:b502ea2d6ebb 701 }
soulx 0:b502ea2d6ebb 702
soulx 0:b502ea2d6ebb 703 }