#include <Wire.h>
#include <DFRobot_QMC5883.h>
DFRobot_QMC5883 compass;
float x = 0;

void setup() {
   Serial.begin(9600);
   while (!compass.begin()){
   Serial.println(" ");
   delay(500);
}
  if(compass.isHMC() ){
    Serial.println(" ");
    compass.setRange(HMC5883L_RANGE_1_3GA);
    compass.setMeasurementMode(HMC5883L_CONTINOUS);
    compass.setDataRate(HMC5883L_DATARATE_15HZ);
    compass.setSamples(HMC5883L_SAMPLES_8);
  }else if(compass.isQMC()){
    Serial.println(" ");
    compass.setRange(QMC5883_RANGE_2GA);
   compass.setMeasurementMode(QMC5883_CONTINOUS);
   compass.setDataRate(QMC5883_DATARATE_50HZ);
    compass.setSamples(QMC5883_SAMPLES_8);
}
}

void loop() {
      Vector mag = compass.readRaw();
      float heading = atan2(mag.YAxis, mag.XAxis);
      float declinationAngle = (4.0 + (26.0 / 60.0)) / (180 / PI);
      heading += declinationAngle;
     if (heading < 0){
       heading += 2 * PI;
      }
      if (heading > 2 * PI){
        heading -= 2 * PI;
      }
      float headingDegrees = heading * 180/PI;
      x = headingDegrees;
     Serial.println(x);
     delay(300);
} 

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