File content as of revision 6:8cd00c26bb47:

#include "chair_imu.h"
 
Serial pc(USBTX, USBRX);
Timer t;

// Default Initialization
chair_imu::chair_imu(){
    imu = new BNO055(SDA, SCL);
}

// Initialize Pins 
chair_imu::chair_imu(PinName SDA_Pin, PinName SCL_Pin){
    imu = new BNO055(SDA_Pin, SCL_Pin);
}
 
// Check to make sure BNO055 is properly working
void chair_imu::setup(){
    imu->reset();
    pc.printf("Bosch Sensortec BNO055 test program on \r\n");
    while (imu->check() == 0) {
        pc.printf("Bosch BNO055 is NOT available!!\r\n");
        wait(.5);
    }
    pc.printf("Bosch Sensortec BNO055 available \r\n");

    //Set the SI units & start the timer
    imu->set_accel_units(MPERSPERS);
    imu->setmode(OPERATION_MODE_AMG);
    imu->set_angle_units(DEGREES);
    imu->get_calib();
    imu->write_calibration_data();
    imu->setmode(OPERATION_MODE_AMG); //put into while loop 
    t.start();
}
 
// Receive acceleration data (in meters per second)
double chair_imu::accel_x(){
    imu->get_accel();
    return (double)imu->accel.x;
}
 
double chair_imu::accel_y(){
    imu->get_accel();
    return (double)imu->accel.y;
}
 
double chair_imu::accel_z(){
    imu->get_accel();
    return (double)imu->accel.z;
}
 
 
// Receive Gyroscope data (in degrees)
double chair_imu::gyro_x(){
    imu->get_gyro();
    return (double)imu->gyro.x;
}
 
double chair_imu::gyro_y(){
    imu->get_gyro();
    return (double)imu->gyro.y;
}
 
double chair_imu::gyro_z(){
    imu->get_gyro();
    return (double)imu->gyro.z;
}


// Receive angle relative to North
double chair_imu::angle_north(){
    imu->get_mag();
    float x = imu->mag.x;
    float y = imu->mag.y;
  
    float result = x/y;
    float angleToNorth;
  
    if(imu->mag.y > 0)
        angleToNorth = 90.0 - atan(result) * 180/PI;
    else if(imu->mag.y < 0)
        angleToNorth = 270.0 - atan(result) * 180/PI;
    else if(y == 0 && x <= 0)
        angleToNorth = 180;
    else if(y == 0 && x > 0)
        angleToNorth = 0;
  
    return (double)angleToNorth;
}
 
// Rotation about the X-axis
double chair_imu::roll(){
    imu->get_accel();
    imu->get_gyro();
  
    float roll = atan2 (-imu->accel.x , (sqrt ((imu->accel.y * imu->accel.y) + 
                       (imu->accel.z * imu->accel.z)) ));
    roll = roll * 57.3;         // Scaling factor   

    t.reset();
 
    return (double)roll;
}

// Rotation about the Y-axis
double chair_imu::pitch(){
    imu->get_accel();
    imu->get_gyro();
  
    float pitch = atan2 (imu->accel.y , (sqrt ((imu->accel.x * imu->accel.x) + 
                        (imu->accel.z * imu->accel.z)) ));
    pitch = pitch * 57.3;       // Scaling Factor

    t.reset();

    return (double)pitch;
}
 
// Rotation about the Z-axis
double chair_imu::yaw(){
    imu->get_gyro();
    float yaw = (yaw - t.read() * imu->gyro.z);

    // Return a yaw value between 0 and 360 degrees
    if(yaw > 360)
    yaw -= 360;
    if(yaw < 0)
    yaw += 360;

    t.reset();

    return (double)yaw;
}