Android sensortag compass azimuth not working (Java code)

Question

Android sensortag compass azimuth not working (Java code)

I am using Sensortag cc2541 as a sensor connected to NEXUX 5 via bluetooth. Thus, the code below is not typical onSensorChanged, since it does NOT use the sensors of the phone itself. Instead, he uses cc2541 sensor methods.

I want to make a simple compass and did some research and came up with the following.

From what I read on the Internet, Azimuth should be the direction (around Z) of the compass. However, I do not get the correct reading.

I also included images showing orientation accelerometerand magnetometersensor.

Accelerometer orientation

Accelerometer

Magnetometer orientation

Magnetometer

the code

public class ManagerListener extends SensorTagLoggerListener implements SensorTagListener {

    private float[] gravityData = new float[3];
    private float[] geomagneticData  = new float[3];
    private double azimuth,pitch,roll;

    @Override
    public void onUpdateAccelerometer(SensorTagManager mgr, Point3D acc) {
        super.onUpdateAccelerometer(mgr, acc);

        gravityData[0] = (float)acc.x;
        gravityData[1] = (float)acc.y;
        gravityData[2] = (float)acc.z;

    }

    @Override
    public void onUpdateMagnetometer(SensorTagManager mgr, Point3D b) {
        super.onUpdateMagnetometer(mgr, b);

        geomagneticData[0] = (float) -b.y;
        geomagneticData[1] = (float) b.x;
        geomagneticData[2] = (float) -b.z;

        float I[] = new float[9];
        float R[] = new float[9];
        boolean success = SensorManager.getRotationMatrix(R, I, gravityData, geomagneticData);

        if (success)
        {
            float orientationMatrix[] = new float[3];
            SensorManager.getOrientation(R, orientationMatrix);
            azimuth = Math.toDegrees(orientationMatrix[0]);
            pitch = Math.toDegrees(orientationMatrix[1]);
            roll = Math.toDegrees(orientationMatrix[2]);
        }

        final float rotation = (float) azimuth;
        final String xyz = "Azimuth:\t" + String.valueOf(Math.round(azimuth)) + 
                           "\nPitch:\t" + String.valueOf(Math.round(pitch)) + 
                           "\nRoll:\t" + String.valueOf(Math.round(roll));

        runOnUiThread(new Runnable() {

            @Override
            public void run() {
                degree.setText(xyz);
                pointer.setRotation(rotation);
            }
        });
    }

}