Pre-test

Dependencies:   LinkedList mbed-rtos mbed

Committer:
Khanchana
Date:
Mon Apr 09 15:57:36 2018 +0000
Revision:
0:d98bd8b7dc46
Pre-test

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Khanchana 0:d98bd8b7dc46 1 #include "MPU9250.h"
Khanchana 0:d98bd8b7dc46 2
Khanchana 0:d98bd8b7dc46 3 MPU9250 mpu9250;
Khanchana 0:d98bd8b7dc46 4
Khanchana 0:d98bd8b7dc46 5 Timer t;
Khanchana 0:d98bd8b7dc46 6
Khanchana 0:d98bd8b7dc46 7 void attitude_setup(void)
Khanchana 0:d98bd8b7dc46 8 {
Khanchana 0:d98bd8b7dc46 9 i2c.frequency(400000); // use fast (400 kHz) I2C
Khanchana 0:d98bd8b7dc46 10
Khanchana 0:d98bd8b7dc46 11 t.start();
Khanchana 0:d98bd8b7dc46 12
Khanchana 0:d98bd8b7dc46 13 // Read the WHO_AM_I register, this is a good test of communication
Khanchana 0:d98bd8b7dc46 14 uint8_t whoami = mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250
Khanchana 0:d98bd8b7dc46 15
Khanchana 0:d98bd8b7dc46 16
Khanchana 0:d98bd8b7dc46 17 if (whoami == 0x73) { // WHO_AM_I should always be 0x68
Khanchana 0:d98bd8b7dc46 18 wait(1);
Khanchana 0:d98bd8b7dc46 19 mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration
Khanchana 0:d98bd8b7dc46 20 mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers
Khanchana 0:d98bd8b7dc46 21 wait(2);
Khanchana 0:d98bd8b7dc46 22 mpu9250.initMPU9250();
Khanchana 0:d98bd8b7dc46 23 mpu9250.initAK8963(magCalibration);
Khanchana 0:d98bd8b7dc46 24 wait(2);
Khanchana 0:d98bd8b7dc46 25 } else while(1) ; // Loop forever if communication doesn't happen
Khanchana 0:d98bd8b7dc46 26
Khanchana 0:d98bd8b7dc46 27 mpu9250.getAres(); // Get accelerometer sensitivity
Khanchana 0:d98bd8b7dc46 28 mpu9250.getGres(); // Get gyro sensitivity
Khanchana 0:d98bd8b7dc46 29 mpu9250.getMres(); // Get magnetometer sensitivity
Khanchana 0:d98bd8b7dc46 30
Khanchana 0:d98bd8b7dc46 31 magbias[0] = +470.; // User environmental x-axis correction in milliGauss, should be automatically calculated
Khanchana 0:d98bd8b7dc46 32 magbias[1] = +120.; // User environmental x-axis correction in milliGauss
Khanchana 0:d98bd8b7dc46 33 magbias[2] = +125.; // User environmental x-axis correction in milliGauss
Khanchana 0:d98bd8b7dc46 34 }
Khanchana 0:d98bd8b7dc46 35
Khanchana 0:d98bd8b7dc46 36 int attitude_get(void)
Khanchana 0:d98bd8b7dc46 37 {
Khanchana 0:d98bd8b7dc46 38 // If intPin goes high, all data registers have new data
Khanchana 0:d98bd8b7dc46 39 if(mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt
Khanchana 0:d98bd8b7dc46 40
Khanchana 0:d98bd8b7dc46 41 mpu9250.readAccelData(accelCount); // Read the x/y/z adc values
Khanchana 0:d98bd8b7dc46 42 // Now we'll calculate the accleration value into actual g's
Khanchana 0:d98bd8b7dc46 43 ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
Khanchana 0:d98bd8b7dc46 44 ay = (float)accelCount[1]*aRes - accelBias[1];
Khanchana 0:d98bd8b7dc46 45 az = (float)accelCount[2]*aRes - accelBias[2];
Khanchana 0:d98bd8b7dc46 46
Khanchana 0:d98bd8b7dc46 47 mpu9250.readGyroData(gyroCount); // Read the x/y/z adc values
Khanchana 0:d98bd8b7dc46 48 // Calculate the gyro value into actual degrees per second
Khanchana 0:d98bd8b7dc46 49 gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
Khanchana 0:d98bd8b7dc46 50 gy = (float)gyroCount[1]*gRes - gyroBias[1];
Khanchana 0:d98bd8b7dc46 51 gz = (float)gyroCount[2]*gRes - gyroBias[2];
Khanchana 0:d98bd8b7dc46 52
Khanchana 0:d98bd8b7dc46 53 mpu9250.readMagData(magCount); // Read the x/y/z adc values
Khanchana 0:d98bd8b7dc46 54 // Calculate the magnetometer values in milliGauss
Khanchana 0:d98bd8b7dc46 55 // Include factory calibration per data sheet and user environmental corrections
Khanchana 0:d98bd8b7dc46 56 mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]; // get actual magnetometer value, this depends on scale being set
Khanchana 0:d98bd8b7dc46 57 my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1];
Khanchana 0:d98bd8b7dc46 58 mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2];
Khanchana 0:d98bd8b7dc46 59
Khanchana 0:d98bd8b7dc46 60
Khanchana 0:d98bd8b7dc46 61 Now = t.read_us();
Khanchana 0:d98bd8b7dc46 62 deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update
Khanchana 0:d98bd8b7dc46 63 lastUpdate = Now;
Khanchana 0:d98bd8b7dc46 64
Khanchana 0:d98bd8b7dc46 65 // Pass gyro rate as rad/s
Khanchana 0:d98bd8b7dc46 66 mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
Khanchana 0:d98bd8b7dc46 67 mpu9250.MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
Khanchana 0:d98bd8b7dc46 68
Khanchana 0:d98bd8b7dc46 69 yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]);
Khanchana 0:d98bd8b7dc46 70 pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
Khanchana 0:d98bd8b7dc46 71 roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]);
Khanchana 0:d98bd8b7dc46 72 pitch *= 180.0f / PI;
Khanchana 0:d98bd8b7dc46 73 yaw *= 180.0f / PI;
Khanchana 0:d98bd8b7dc46 74 yaw -= 13.8f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04
Khanchana 0:d98bd8b7dc46 75 roll *= 180.0f / PI;
Khanchana 0:d98bd8b7dc46 76
Khanchana 0:d98bd8b7dc46 77 return 0;
Khanchana 0:d98bd8b7dc46 78 }
Khanchana 0:d98bd8b7dc46 79 return -1;
Khanchana 0:d98bd8b7dc46 80 }
Khanchana 0:d98bd8b7dc46 81