Patrick Ciccone
MPU9250 library fork
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MPU9250.h
00001 /* 00002 TODO: 00003 add configuration function: 00004 loop through mux 00005 if imu 00006 append imu to a list 00007 ... 00008 ... 00009 if list > 0 00010 return something good 00011 00012 add config output function 00013 00014 00015 00016 00017 */ 00018 00019 00020 #ifndef MPU9250_H 00021 #define MPU9250_H 00022 00023 #include "mbed.h" 00024 #include "math.h" 00025 #include "MadgwickAHRS.h" 00026 00027 // See also MPU-9250 Register Map and Descriptions, Revision 4.0, RM-MPU-9250A-00, Rev. 1.4, 9/9/2013 for registers not listed in 00028 // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map 00029 // 00030 //Magnetometer Registers 00031 #define AK8963_ADDRESS 0x0C<<1 00032 #define WHO_AM_I_AK8963 0x00 // should return 0x48 00033 #define INFO 0x01 00034 #define AK8963_ST1 0x02 // data ready status bit 0 00035 #define AK8963_XOUT_L 0x03 // data 00036 #define AK8963_XOUT_H 0x04 00037 #define AK8963_YOUT_L 0x05 00038 #define AK8963_YOUT_H 0x06 00039 #define AK8963_ZOUT_L 0x07 00040 #define AK8963_ZOUT_H 0x08 00041 #define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status bit 2 00042 #define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001), self-test (1000) and Fuse ROM (1111) modes on bits 3:0 00043 #define AK8963_ASTC 0x0C // Self test control 00044 #define AK8963_I2CDIS 0x0F // I2C disable 00045 #define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value 00046 #define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value 00047 #define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value 00048 00049 #define SELF_TEST_X_GYRO 0x00 00050 #define SELF_TEST_Y_GYRO 0x01 00051 #define SELF_TEST_Z_GYRO 0x02 00052 00053 /*#define X_FINE_GAIN 0x03 // [7:0] fine gain 00054 #define Y_FINE_GAIN 0x04 00055 #define Z_FINE_GAIN 0x05 00056 #define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer 00057 #define XA_OFFSET_L_TC 0x07 00058 #define YA_OFFSET_H 0x08 00059 #define YA_OFFSET_L_TC 0x09 00060 #define ZA_OFFSET_H 0x0A 00061 #define ZA_OFFSET_L_TC 0x0B */ 00062 00063 #define SELF_TEST_X_ACCEL 0x0D 00064 #define SELF_TEST_Y_ACCEL 0x0E 00065 #define SELF_TEST_Z_ACCEL 0x0F 00066 00067 #define SELF_TEST_A 0x10 00068 00069 #define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope 00070 #define XG_OFFSET_L 0x14 00071 #define YG_OFFSET_H 0x15 00072 #define YG_OFFSET_L 0x16 00073 #define ZG_OFFSET_H 0x17 00074 #define ZG_OFFSET_L 0x18 00075 #define SMPLRT_DIV 0x19 00076 #define CONFIG 0x1A 00077 #define GYRO_CONFIG 0x1B 00078 #define ACCEL_CONFIG 0x1C 00079 #define ACCEL_CONFIG2 0x1D 00080 #define LP_ACCEL_ODR 0x1E 00081 #define WOM_THR 0x1F 00082 00083 #define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms 00084 #define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0] 00085 #define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms 00086 00087 #define FIFO_EN 0x23 00088 #define I2C_MST_CTRL 0x24 00089 #define I2C_SLV0_ADDR 0x25 00090 #define I2C_SLV0_REG 0x26 00091 #define I2C_SLV0_CTRL 0x27 00092 #define I2C_SLV1_ADDR 0x28 00093 #define I2C_SLV1_REG 0x29 00094 #define I2C_SLV1_CTRL 0x2A 00095 #define I2C_SLV2_ADDR 0x2B 00096 #define I2C_SLV2_REG 0x2C 00097 #define I2C_SLV2_CTRL 0x2D 00098 #define I2C_SLV3_ADDR 0x2E 00099 #define I2C_SLV3_REG 0x2F 00100 #define I2C_SLV3_CTRL 0x30 00101 #define I2C_SLV4_ADDR 0x31 00102 #define I2C_SLV4_REG 0x32 00103 #define I2C_SLV4_DO 0x33 00104 #define I2C_SLV4_CTRL 0x34 00105 #define I2C_SLV4_DI 0x35 00106 #define I2C_MST_STATUS 0x36 00107 #define INT_PIN_CFG 0x37 00108 #define INT_ENABLE 0x38 00109 #define DMP_INT_STATUS 0x39 // Check DMP interrupt 00110 #define INT_STATUS 0x3A 00111 #define ACCEL_XOUT_H 0x3B 00112 #define ACCEL_XOUT_L 0x3C 00113 #define ACCEL_YOUT_H 0x3D 00114 #define ACCEL_YOUT_L 0x3E 00115 #define ACCEL_ZOUT_H 0x3F 00116 #define ACCEL_ZOUT_L 0x40 00117 #define TEMP_OUT_H 0x41 00118 #define TEMP_OUT_L 0x42 00119 #define GYRO_XOUT_H 0x43 00120 #define GYRO_XOUT_L 0x44 00121 #define GYRO_YOUT_H 0x45 00122 #define GYRO_YOUT_L 0x46 00123 #define GYRO_ZOUT_H 0x47 00124 #define GYRO_ZOUT_L 0x48 00125 #define EXT_SENS_DATA_00 0x49 00126 #define EXT_SENS_DATA_01 0x4A 00127 #define EXT_SENS_DATA_02 0x4B 00128 #define EXT_SENS_DATA_03 0x4C 00129 #define EXT_SENS_DATA_04 0x4D 00130 #define EXT_SENS_DATA_05 0x4E 00131 #define EXT_SENS_DATA_06 0x4F 00132 #define EXT_SENS_DATA_07 0x50 00133 #define EXT_SENS_DATA_08 0x51 00134 #define EXT_SENS_DATA_09 0x52 00135 #define EXT_SENS_DATA_10 0x53 00136 #define EXT_SENS_DATA_11 0x54 00137 #define EXT_SENS_DATA_12 0x55 00138 #define EXT_SENS_DATA_13 0x56 00139 #define EXT_SENS_DATA_14 0x57 00140 #define EXT_SENS_DATA_15 0x58 00141 #define EXT_SENS_DATA_16 0x59 00142 #define EXT_SENS_DATA_17 0x5A 00143 #define EXT_SENS_DATA_18 0x5B 00144 #define EXT_SENS_DATA_19 0x5C 00145 #define EXT_SENS_DATA_20 0x5D 00146 #define EXT_SENS_DATA_21 0x5E 00147 #define EXT_SENS_DATA_22 0x5F 00148 #define EXT_SENS_DATA_23 0x60 00149 #define MOT_DETECT_STATUS 0x61 00150 #define I2C_SLV0_DO 0x63 00151 #define I2C_SLV1_DO 0x64 00152 #define I2C_SLV2_DO 0x65 00153 #define I2C_SLV3_DO 0x66 00154 #define I2C_MST_DELAY_CTRL 0x67 00155 #define SIGNAL_PATH_RESET 0x68 00156 #define MOT_DETECT_CTRL 0x69 00157 #define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP 00158 #define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode 00159 #define PWR_MGMT_2 0x6C 00160 #define DMP_BANK 0x6D // Activates a specific bank in the DMP 00161 #define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank 00162 #define DMP_REG 0x6F // Register in DMP from which to read or to which to write 00163 #define DMP_REG_1 0x70 00164 #define DMP_REG_2 0x71 00165 #define FIFO_COUNTH 0x72 00166 #define FIFO_COUNTL 0x73 00167 #define FIFO_R_W 0x74 00168 #define WHO_AM_I_MPU9250 0x75 // Should return 0x71 00169 #define XA_OFFSET_H 0x77 00170 #define XA_OFFSET_L 0x78 00171 #define YA_OFFSET_H 0x7A 00172 #define YA_OFFSET_L 0x7B 00173 #define ZA_OFFSET_H 0x7D 00174 #define ZA_OFFSET_L 0x7E 00175 00176 // Using the MSENSR-9250 breakout board, ADO is set to 0 00177 // Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1 00178 //mbed uses the eight-bit device address, so shift seven-bit addresses left by one! 00179 #define ADO 0 00180 #if ADO 00181 #define MPU9250_ADDRESS 0x69<<1 // Device address when ADO = 1 00182 #else 00183 #define MPU9250_ADDRESS 0x68<<1 // Device address when ADO = 0 00184 #endif 00185 00186 // Set initial input parameters 00187 enum Ascale { 00188 AFS_2G = 0, 00189 AFS_4G, 00190 AFS_8G, 00191 AFS_16G 00192 }; 00193 00194 enum Gscale { 00195 GFS_250DPS = 0, 00196 GFS_500DPS, 00197 GFS_1000DPS, 00198 GFS_2000DPS 00199 }; 00200 00201 enum Mscale { 00202 MFS_14BITS = 0, // 0.6 mG per LSB 00203 MFS_16BITS // 0.15 mG per LSB 00204 }; 00205 00206 uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G 00207 uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS 00208 uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution 00209 uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR 00210 float aRes, gRes, mRes; // scale resolutions per LSB for the sensors 00211 00212 //Set up I2C, (SDA,SCL) 00213 I2C i2c(I2C_SDA, I2C_SCL); 00214 00215 DigitalOut myled(LED1); 00216 00217 // Pin definitions 00218 int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins 00219 00220 float SelfTest[6]; 00221 00222 int delt_t = 0; // used to control display output rate 00223 int count = 0; // used to control display output rate 00224 00225 // parameters for 6 DoF sensor fusion calculations 00226 float PI = 3.14159265358979323846f; 00227 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 00228 //float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta 00229 float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s) 00230 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 00231 #define Kp 2.0f * 5.0f // these are the free parameters in the Mahony filter and fusion scheme, Kp for proportional feedback, Ki for integral 00232 #define Ki 0.0f 00233 00234 00235 00236 class MPU9250 00237 { 00238 00239 protected: 00240 00241 public: 00242 int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output 00243 int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output 00244 int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output 00245 float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values 00246 float magCalibration[3]; 00247 float magbias[3]; // Factory mag calibration and mag bias 00248 float gyroBias[3]; 00249 float accelBias[3]; // Bias corrections for gyro and accelerometer 00250 int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius 00251 float temperature; 00252 float pitch, yaw, roll; 00253 float deltat; // integration interval for both filter schemes 00254 int lastUpdate; 00255 int firstUpdate; 00256 int Now; // used to calculate integration interval 00257 float q[4]; // vector to hold quaternion 00258 float eInt[3]; // vector to hold integral error for Mahony method 00259 uint32_t checksum; 00260 00261 MPU9250() { 00262 ax=ay=az=gx=gy=gz=mx=my=mz=0.0; 00263 for (int i = 0; i < 3; i++) { 00264 magCalibration[i] = 0.0; 00265 magbias[i] = 0.0; 00266 gyroBias[i] = 0.0; 00267 accelBias[i] = 0.0; 00268 eInt[i] = 0.0f; 00269 } // end of for 00270 q[0] = 1.0f; 00271 q[1] = 0.0f; 00272 q[2] = 0.0f; 00273 q[3] = 0.0f; 00274 lastUpdate = 0, firstUpdate = 0, Now = 0; 00275 deltat = 0.0f; 00276 } // end of initalizer 00277 00278 //=================================================================================================================== 00279 //====== Set of useful function to access acceleratio, gyroscope, and temperature data 00280 //=================================================================================================================== 00281 00282 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data) { 00283 char data_write[2]; 00284 data_write[0] = subAddress; 00285 data_write[1] = data; 00286 i2c.write(address, data_write, 2, 0); 00287 } 00288 00289 00290 void selfTest(Serial &pc , bool show = false) { 00291 resetMPU9250(); // Reset registers to default in preparation for device calibration 00292 MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values 00293 if (show) { 00294 pc.printf("x-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[0]); 00295 pc.printf("y-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[1]); 00296 pc.printf("z-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[2]); 00297 pc.printf("x-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[3]); 00298 pc.printf("y-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[4]); 00299 pc.printf("z-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[5]); 00300 } 00301 //calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers 00302 if(show) { 00303 pc.printf("x gyro bias = %f\n\r", gyroBias[0]); 00304 pc.printf("y gyro bias = %f\n\r", gyroBias[1]); 00305 pc.printf("z gyro bias = %f\n\r", gyroBias[2]); 00306 pc.printf("x accel bias = %f\n\r", accelBias[0]); 00307 pc.printf("y accel bias = %f\n\r", accelBias[1]); 00308 pc.printf("z accel bias = %f\n\r", accelBias[2]); 00309 } 00310 } 00311 00312 00313 void config(Serial &pc, bool show = false) { 00314 initMPU9250(); 00315 if (show) 00316 pc.printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature 00317 initAK8963(magCalibration); 00318 if(show) { 00319 pc.printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer 00320 pc.printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale)); 00321 pc.printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale)); 00322 if(Mscale == 0) pc.printf("Magnetometer resolution = 14 bits\n\r"); 00323 if(Mscale == 1) pc.printf("Magnetometer resolution = 16 bits\n\r"); 00324 if(Mmode == 2) pc.printf("Magnetometer ODR = 8 Hz\n\r"); 00325 if(Mmode == 6) pc.printf("Magnetometer ODR = 100 Hz\n\r"); 00326 pc.printf("mag calibration: \r\nx:\t%f\r\ny:\t%f\r\nz:\t%f\r\n", magbias[0], magbias[1], magbias[2]); 00327 } 00328 } 00329 00330 00331 void sensitivity(Serial &pc, bool show = false) { 00332 getAres(); // Get accelerometer sensitivity 00333 getGres(); // Get gyro sensitivity 00334 getMres(); // Get magnetometer sensitivity 00335 if (show) { 00336 pc.printf("Accelerometer sensitivity is %f LSB/g \n\r", 1.0f/aRes); 00337 pc.printf("Gyroscope sensitivity is %f LSB/deg/s \n\r", 1.0f/gRes); 00338 pc.printf("Magnetometer sensitivity is %f LSB/G \n\r", 1.0f/mRes); 00339 } 00340 } 00341 00342 00343 char readByte(uint8_t address, uint8_t subAddress) { 00344 char data[1]; // `data` will store the register data 00345 char data_write[1]; 00346 data_write[0] = subAddress; 00347 i2c.write(address, data_write, 1, 1); // no stop 00348 i2c.read(address, data, 1, 0); 00349 return data[0]; 00350 } 00351 00352 00353 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) { 00354 char data[14]; 00355 char data_write[1]; 00356 data_write[0] = subAddress; 00357 i2c.write(address, data_write, 1, 1); // no stop 00358 i2c.read(address, data, count, 0); 00359 for(int ii = 0; ii < count; ii++) { 00360 dest[ii] = data[ii]; 00361 } 00362 } 00363 00364 00365 void getMres() { 00366 switch (Mscale) { 00367 // Possible magnetometer scales (and their register bit settings) are: 00368 // 14 bit resolution (0) and 16 bit resolution (1) 00369 case MFS_14BITS: 00370 mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss 00371 break; 00372 case MFS_16BITS: 00373 mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss 00374 break; 00375 } 00376 } 00377 00378 00379 void getGres() { 00380 switch (Gscale) { 00381 // Possible gyro scales (and their register bit settings) are: 00382 // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11). 00383 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: 00384 case GFS_250DPS: 00385 gRes = 250.0/32768.0; 00386 break; 00387 case GFS_500DPS: 00388 gRes = 500.0/32768.0; 00389 break; 00390 case GFS_1000DPS: 00391 gRes = 1000.0/32768.0; 00392 break; 00393 case GFS_2000DPS: 00394 gRes = 2000.0/32768.0; 00395 break; 00396 } 00397 } 00398 00399 00400 void getAres() { 00401 switch (Ascale) { 00402 // Possible accelerometer scales (and their register bit settings) are: 00403 // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11). 00404 // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: 00405 case AFS_2G: 00406 aRes = 2.0/32768.0; 00407 break; 00408 case AFS_4G: 00409 aRes = 4.0/32768.0; 00410 break; 00411 case AFS_8G: 00412 aRes = 8.0/32768.0; 00413 break; 00414 case AFS_16G: 00415 aRes = 16.0/32768.0; 00416 break; 00417 } 00418 } 00419 00420 00421 void readAccelData() { 00422 uint8_t rawData[6]; // x/y/z accel register data stored here 00423 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array 00424 ax = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value 00425 ay = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; 00426 az = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; 00427 } 00428 00429 void readGyroData() { 00430 uint8_t rawData[6]; // x/y/z gyro register data stored here 00431 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]) ; // Read the six raw data registers sequentially into data array 00432 gx = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value 00433 gy = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; 00434 gz = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; 00435 } 00436 00437 void readMagData() { 00438 uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition 00439 if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { 00440 // wait for magnetometer data ready bit to be set 00441 readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array 00442 uint8_t c = rawData[6]; // End data read by reading ST2 register 00443 if(!(c & 0x08)) { 00444 // Check if magnetic sensor overflow set, if not then report data 00445 mx = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]) ; // Turn the MSB and LSB into a signed 16-bit value 00446 my = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian 00447 mz = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ; 00448 } 00449 } 00450 } 00451 00452 void readimu() { 00453 readAccelData(); 00454 ax = ax*aRes - accelBias[0]; 00455 ay = ay*aRes - accelBias[1]; 00456 az = az*aRes - accelBias[2]; 00457 00458 readGyroData(); 00459 gx = gx*gRes - gyroBias[0]; 00460 gy = gy*gRes - gyroBias[1]; 00461 gz = gz*gRes - gyroBias[2]; 00462 00463 // Calculate the magnetometer values in milliGauss 00464 // Include factory calibration per data sheet and user environmental corrections 00465 readMagData(); 00466 mx = mx*mRes*magCalibration[0] - magbias[0]; 00467 my = my*mRes*magCalibration[1] - magbias[1]; 00468 mz = mz*mRes*magCalibration[2] - magbias[2]; 00469 00470 checksum = 0; 00471 checksum += int(1000*ax) + int(1000*ay) + int(1000*az) +int(gx) + int(gy) + int(gz) +int(mx) + int(my) + int(mz); 00472 00473 }// end of read IMUData() 00474 00475 int16_t readTempData() { 00476 uint8_t rawData[2]; // x/y/z gyro register data stored here 00477 readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array 00478 return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value 00479 } 00480 00481 00482 void resetMPU9250() { 00483 // reset device 00484 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device 00485 wait(0.1); 00486 } 00487 00488 void initAK8963(float * destination) { 00489 // First extract the factory calibration for each magnetometer axis 00490 uint8_t rawData[3]; // x/y/z gyro calibration data stored here 00491 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer 00492 wait(0.01); 00493 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode 00494 wait(0.01); 00495 readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values 00496 destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc. 00497 destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f; 00498 destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f; 00499 writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer 00500 wait(0.01); 00501 // Configure the magnetometer for continuous read and highest resolution 00502 // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register, 00503 // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates 00504 writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR 00505 wait(0.01); 00506 } 00507 00508 00509 void initMPU9250() { 00510 // Initialize MPU9250 device 00511 // wake up device 00512 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors 00513 wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt 00514 00515 // get stable time source 00516 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001 00517 00518 // Configure Gyro and Accelerometer 00519 // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively; 00520 // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both 00521 // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate 00522 writeByte(MPU9250_ADDRESS, CONFIG, 0x03); 00523 00524 // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV) 00525 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above 00526 00527 // Set gyroscope full scale range 00528 // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3 00529 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG); 00530 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5] 00531 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3] 00532 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro 00533 00534 // Set accelerometer configuration 00535 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG); 00536 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5] 00537 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3] 00538 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer 00539 00540 // Set accelerometer sample rate configuration 00541 // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for 00542 // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz 00543 c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2); 00544 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0]) 00545 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz 00546 00547 // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates, 00548 // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting 00549 00550 // Configure Interrupts and Bypass Enable 00551 // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips 00552 // can join the I2C bus and all can be controlled by the Arduino as master 00553 writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22); 00554 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt 00555 } 00556 00557 //void calibrateMag(float * dest1, float * dest2, Serial &pc) 00558 void calibrateMag(Serial &pc) { 00559 uint16_t ii = 0, sample_count = 0; 00560 //int32_t mag_bias[3] = {0, 0, 0}; 00561 int32_t mag_scale[3] = {0, 0, 0}; 00562 int16_t mag_max[3] = {0x8000, 0x8000, 0x8000}; 00563 int16_t mag_min[3] = {0x7FFF, 0x7FFF, 0x7FFF}; 00564 int16_t mag_temp[3] = {0, 0, 0}; 00565 pc.printf("Pre-Mag Calibration: \r\nx:\t%f\r\ny:\t%f\r\nz:\t%f\r\n", magbias[0], magbias[1], magbias[2]); 00566 pc.printf("Mag Calibration: Wave device in a figure eight until done!\n"); 00567 wait(4); 00568 00569 sample_count = 500; 00570 for(ii = 0; ii < sample_count; ii++) { 00571 //readMagData(mag_temp); // Read the mag data 00572 for (int jj = 0; jj < 3; jj++) { 00573 if(mag_temp[jj] > mag_max[jj]) mag_max[jj] = mag_temp[jj]; 00574 if(mag_temp[jj] < mag_min[jj]) mag_min[jj] = mag_temp[jj]; 00575 }// end of inner for 00576 wait(.035); // at 8 Hz ODR, new mag data is available every 125 ms 00577 pc.printf("%d\t%d\t%d\r\n", mag_temp[0], mag_temp[1], mag_temp[2]); 00578 }// end of outer for 00579 wait(1); 00580 pc.printf("%d\t%d\t%d\t%d\t%d\t%d\r\n", mag_min[0], mag_max[0], mag_min[1], mag_max[1], mag_min[2], mag_max[2]); 00581 wait(10); 00582 // Get hard iron correction 00583 magbias[0] = (mag_max[0] + mag_min[0])/2; // get average x mag bias in counts 00584 magbias[1] = (mag_max[1] + mag_min[1])/2; // get average y mag bias in counts 00585 magbias[2] = (mag_max[2] + mag_min[2])/2; // get average z mag bias in counts 00586 00587 //dest1[0] = (float) mag_bias[0]*mRes*MPU9250magCalibration[0]; // save mag biases in G for main program 00588 //dest1[1] = (float) mag_bias[1]*mRes*MPU9250magCalibration[1]; 00589 //dest1[2] = (float) mag_bias[2]*mRes*MPU9250magCalibration[2]; 00590 00591 // Get soft iron correction estimate 00592 mag_scale[0] = (mag_max[0] - mag_min[0])/2; // get average x axis max chord length in counts 00593 mag_scale[1] = (mag_max[1] - mag_min[1])/2; // get average y axis max chord length in counts 00594 mag_scale[2] = (mag_max[2] - mag_min[2])/2; // get average z axis max chord length in counts 00595 00596 float avg_rad = mag_scale[0] + mag_scale[1] + mag_scale[2]; 00597 avg_rad /= 3.0; 00598 00599 //dest2[0] = avg_rad/((float)mag_scale[0]); 00600 //dest2[1] = avg_rad/((float)mag_scale[1]); 00601 //dest2[2] = avg_rad/((float)mag_scale[2]); 00602 pc.printf("Post-Mag Calibration: \r\nx:\t%f\r\ny:\t%f\r\nz:\t%f\r\n", magbias[0], magbias[1], magbias[2]); 00603 pc.printf("Mag Calibration done!\n"); 00604 }// end of calibrateMag 00605 00606 // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average 00607 // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers. 00608 void calibrateMPU9250(float * dest1, float * dest2) { 00609 uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data 00610 uint16_t ii, packet_count, fifo_count; 00611 int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0}; 00612 00613 // reset device, reset all registers, clear gyro and accelerometer bias registers 00614 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device 00615 wait(0.1); 00616 00617 // get stable time source 00618 // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001 00619 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); 00620 writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00); 00621 wait(0.2); 00622 00623 // Configure device for bias calculation 00624 writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts 00625 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO 00626 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source 00627 writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master 00628 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes 00629 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP 00630 wait(0.015); 00631 00632 // Configure MPU9250 gyro and accelerometer for bias calculation 00633 writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz 00634 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz 00635 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity 00636 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity 00637 00638 uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec 00639 uint16_t accelsensitivity = 16384; // = 16384 LSB/g 00640 00641 // Configure FIFO to capture accelerometer and gyro data for bias calculation 00642 writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO 00643 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250) 00644 wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes 00645 00646 // At end of sample accumulation, turn off FIFO sensor read 00647 writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO 00648 readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count 00649 fifo_count = ((uint16_t)data[0] << 8) | data[1]; 00650 packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging 00651 00652 for (ii = 0; ii < packet_count; ii++) { 00653 int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0}; 00654 readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging 00655 accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO 00656 accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ; 00657 accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ; 00658 gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ; 00659 gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ; 00660 gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ; 00661 00662 accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases 00663 accel_bias[1] += (int32_t) accel_temp[1]; 00664 accel_bias[2] += (int32_t) accel_temp[2]; 00665 gyro_bias[0] += (int32_t) gyro_temp[0]; 00666 gyro_bias[1] += (int32_t) gyro_temp[1]; 00667 gyro_bias[2] += (int32_t) gyro_temp[2]; 00668 00669 } 00670 accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases 00671 accel_bias[1] /= (int32_t) packet_count; 00672 accel_bias[2] /= (int32_t) packet_count; 00673 gyro_bias[0] /= (int32_t) packet_count; 00674 gyro_bias[1] /= (int32_t) packet_count; 00675 gyro_bias[2] /= (int32_t) packet_count; 00676 00677 if(accel_bias[2] > 0L) { 00678 accel_bias[2] -= (int32_t) accelsensitivity; // Remove gravity from the z-axis accelerometer bias calculation 00679 } else { 00680 accel_bias[2] += (int32_t) accelsensitivity; 00681 } 00682 00683 // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup 00684 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 00685 data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases 00686 data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF; 00687 data[3] = (-gyro_bias[1]/4) & 0xFF; 00688 data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF; 00689 data[5] = (-gyro_bias[2]/4) & 0xFF; 00690 00691 /// Push gyro biases to hardware registers 00692 /* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]); 00693 writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]); 00694 writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]); 00695 writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]); 00696 writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]); 00697 writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]); 00698 */ 00699 dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction 00700 dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity; 00701 dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity; 00702 00703 // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain 00704 // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold 00705 // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature 00706 // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that 00707 // the accelerometer biases calculated above must be divided by 8. 00708 00709 int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases 00710 readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values 00711 accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1]; 00712 readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]); 00713 accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1]; 00714 readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]); 00715 accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1]; 00716 00717 uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers 00718 uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis 00719 00720 for(ii = 0; ii < 3; ii++) { 00721 if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit 00722 } 00723 00724 // Construct total accelerometer bias, including calculated average accelerometer bias from above 00725 accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale) 00726 accel_bias_reg[1] -= (accel_bias[1]/8); 00727 accel_bias_reg[2] -= (accel_bias[2]/8); 00728 00729 data[0] = (accel_bias_reg[0] >> 8) & 0xFF; 00730 data[1] = (accel_bias_reg[0]) & 0xFF; 00731 data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers 00732 data[2] = (accel_bias_reg[1] >> 8) & 0xFF; 00733 data[3] = (accel_bias_reg[1]) & 0xFF; 00734 data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers 00735 data[4] = (accel_bias_reg[2] >> 8) & 0xFF; 00736 data[5] = (accel_bias_reg[2]) & 0xFF; 00737 data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers 00738 00739 // Apparently this is not working for the acceleration biases in the MPU-9250 00740 // Are we handling the temperature correction bit properly? 00741 // Push accelerometer biases to hardware registers 00742 /* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]); 00743 writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]); 00744 writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]); 00745 writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]); 00746 writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]); 00747 writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]); 00748 */ 00749 // Output scaled accelerometer biases for manual subtraction in the main program 00750 dest2[0] = (float)accel_bias[0]/(float)accelsensitivity; 00751 dest2[1] = (float)accel_bias[1]/(float)accelsensitivity; 00752 dest2[2] = (float)accel_bias[2]/(float)accelsensitivity; 00753 } 00754 00755 00756 // Accelerometer and gyroscope self test; check calibration wrt factory settings 00757 void MPU9250SelfTest(float * destination) { // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass 00758 uint8_t rawData[6] = {0, 0, 0, 0, 0, 0}; 00759 uint8_t selfTest[6]; 00760 int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3]; 00761 float factoryTrim[6]; 00762 uint8_t FS = 0; 00763 00764 writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz 00765 writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz 00766 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps 00767 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz 00768 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g 00769 00770 for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer 00771 00772 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array 00773 aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value 00774 aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; 00775 aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; 00776 00777 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array 00778 gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value 00779 gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; 00780 gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; 00781 } 00782 00783 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings 00784 aAvg[ii] /= 200; 00785 gAvg[ii] /= 200; 00786 } 00787 00788 // Configure the accelerometer for self-test 00789 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g 00790 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s 00791 wait_ms(25); // Delay a while to let the device stabilize 00792 00793 for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer 00794 00795 readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array 00796 aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value 00797 aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; 00798 aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; 00799 00800 readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array 00801 gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value 00802 gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; 00803 gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; 00804 } 00805 00806 for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings 00807 aSTAvg[ii] /= 200; 00808 gSTAvg[ii] /= 200; 00809 } 00810 00811 // Configure the gyro and accelerometer for normal operation 00812 writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); 00813 writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); 00814 wait_ms(25); // Delay a while to let the device stabilize 00815 00816 // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg 00817 selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results 00818 selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results 00819 selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results 00820 selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results 00821 selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results 00822 selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results 00823 00824 // Retrieve factory self-test value from self-test code reads 00825 factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation 00826 factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation 00827 factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation 00828 factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation 00829 factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation 00830 factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation 00831 00832 // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response 00833 // To get percent, must multiply by 100 00834 for (int i = 0; i < 3; i++) { 00835 destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences 00836 destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences 00837 } 00838 00839 } 00840 00841 // use the madgwick open source version 00842 void Madgwickupdate() 00843 { 00844 // need to convert the gyro measurements 00845 // need to flip the mag x/y coordinates and invert the z axis to match the acell and gyro axis 00846 MadgwickAHRSupdate( gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, ax, ay, az, my, mx, -1.0f*mz, q[0], q[1], q[2], q[3]); 00847 } 00848 00849 // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays" 00850 // (see http://www.x-io.co.uk/category/open-source/ for examples and more details) 00851 // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute 00852 // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc. 00853 // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms 00854 // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz! 00855 void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) { 00856 float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability 00857 float norm; 00858 float hx, hy, _2bx, _2bz; 00859 float s1, s2, s3, s4; 00860 float qDot1, qDot2, qDot3, qDot4; 00861 00862 // Auxiliary variables to avoid repeated arithmetic 00863 float _2q1mx; 00864 float _2q1my; 00865 float _2q1mz; 00866 float _2q2mx; 00867 float _4bx; 00868 float _4bz; 00869 float _2q1 = 2.0f * q1; 00870 float _2q2 = 2.0f * q2; 00871 float _2q3 = 2.0f * q3; 00872 float _2q4 = 2.0f * q4; 00873 float _2q1q3 = 2.0f * q1 * q3; 00874 float _2q3q4 = 2.0f * q3 * q4; 00875 float q1q1 = q1 * q1; 00876 float q1q2 = q1 * q2; 00877 float q1q3 = q1 * q3; 00878 float q1q4 = q1 * q4; 00879 float q2q2 = q2 * q2; 00880 float q2q3 = q2 * q3; 00881 float q2q4 = q2 * q4; 00882 float q3q3 = q3 * q3; 00883 float q3q4 = q3 * q4; 00884 float q4q4 = q4 * q4; 00885 00886 // Normalise accelerometer measurement 00887 norm = sqrt(ax * ax + ay * ay + az * az); 00888 if (norm == 0.0f) return; // handle NaN 00889 norm = 1.0f/norm; 00890 ax *= norm; 00891 ay *= norm; 00892 az *= norm; 00893 00894 // Normalise magnetometer measurement 00895 norm = sqrt(mx * mx + my * my + mz * mz); 00896 if (norm == 0.0f) return; // handle NaN 00897 norm = 1.0f/norm; 00898 mx *= norm; 00899 my *= norm; 00900 mz *= norm; 00901 00902 // Reference direction of Earth's magnetic field 00903 _2q1mx = 2.0f * q1 * mx; 00904 _2q1my = 2.0f * q1 * my; 00905 _2q1mz = 2.0f * q1 * mz; 00906 _2q2mx = 2.0f * q2 * mx; 00907 hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4; 00908 hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4; 00909 _2bx = sqrt(hx * hx + hy * hy); 00910 _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4; 00911 _4bx = 2.0f * _2bx; 00912 _4bz = 2.0f * _2bz; 00913 00914 // Gradient decent algorithm corrective step 00915 s1 = -_2q3 * (2.0f * q2q4 - _2q1q3 - ax) + _2q2 * (2.0f * q1q2 + _2q3q4 - ay) - _2bz * q3 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q4 + _2bz * q2) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q3 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); 00916 s2 = _2q4 * (2.0f * q2q4 - _2q1q3 - ax) + _2q1 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q2 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + _2bz * q4 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q3 + _2bz * q1) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q4 - _4bz * q2) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); 00917 s3 = -_2q1 * (2.0f * q2q4 - _2q1q3 - ax) + _2q4 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q3 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + (-_4bx * q3 - _2bz * q1) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q2 + _2bz * q4) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q1 - _4bz * q3) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); 00918 s4 = _2q2 * (2.0f * q2q4 - _2q1q3 - ax) + _2q3 * (2.0f * q1q2 + _2q3q4 - ay) + (-_4bx * q4 + _2bz * q2) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q1 + _2bz * q3) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q2 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); 00919 norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude 00920 norm = 1.0f/norm; 00921 s1 *= norm; 00922 s2 *= norm; 00923 s3 *= norm; 00924 s4 *= norm; 00925 00926 // Compute rate of change of quaternion 00927 qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1; 00928 qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2; 00929 qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3; 00930 qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4; 00931 00932 // Integrate to yield quaternion 00933 q1 += qDot1 * deltat; 00934 q2 += qDot2 * deltat; 00935 q3 += qDot3 * deltat; 00936 q4 += qDot4 * deltat; 00937 norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion 00938 norm = 1.0f/norm; 00939 q[0] = q1 * norm; 00940 q[1] = q2 * norm; 00941 q[2] = q3 * norm; 00942 q[3] = q4 * norm; 00943 00944 } 00945 }; 00946 #endif
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