File content as of revision 0:6bc5f85ca6fa:

#include "mbed.h"
#include "HMC5883L.h"

#include <math.h>

#define SDA      p9
#define SCL      p10
#define PI       3.14159265

int main()
{      
    float x, y, z, heading;
    /*
    float m_x, m_y, m_z;
    */
    printf("Inicializing...\r\n");
    HMC5883L hmc5883l(SDA, SCL);
    //HMC5883L *hmc5883l = new HMC5883L(SDA, SCL);
    printf("OK...\r\n");
    /*
    for (int i = 0 ; i < 100 ; i++)
    {
        x += hmc5883l.getMx()/100;
        y += hmc5883l.getMy()/100;
        z += hmc5883l.getMz()/100;
        wait_ms(100);
    }
    

    m_x = x/2;
    m_y = y/2;
    m_z = z/2;
    */
    wait(1);

    while(1) 
    { 
        /*
        x = m_x - hmc5883l.getMx()*0.92;
        y = m_y - hmc5883l.getMy()*0.92;
        z = m_z - hmc5883l.getMz()*0.92;
        */
        x = hmc5883l.getMx();
        y = hmc5883l.getMy();
        z = hmc5883l.getMz();
        
        heading = atan2(y, x);
        if(heading < 0) 
            heading += 2*PI;
        if(heading > 2*PI) 
            heading -= 2*PI;
        
        heading = heading * 180 / PI;
        
        // Correct for when signs are reversed.
        //if(heading < 0) 
        //    heading += 2*PI;
        //if(heading > 2*PI) 
        //    heading -= 2*PI;
       
        //while(heading < 0) heading += 360;
        //while(heading > 360) heading -= 360;


        printf("x: %f \t\ty: %f \t\t z: %f \t\t heading: %f \t\r\n", x, y, z, heading);
        wait_ms(200);

    }
}