Heading for HMC6343

Software Particle
1

Hello,
I need to make a compass with a HMC6343, but in the example code provided I cant see where I can obtain an heading from only mag and accl. Im sure I can get heading from the HMC6343 but im not sure where I can find some example code for this. Pitch, roll, and heading are not in the example code. Any help is appreciated.

// Distributed with a free-will license.
// Use it any way you want, profit or free, provided it fits in the licenses of its associated works.
// HMC6343A
// This code is designed to work with the HMC6343A_I2CS I2C Mini Module available from ControlEverything.com.
// https://www.controleverything.com/content/Accelorometer?sku=HMC6343A_I2CS#tabs-0-product_tabset-2

#include <application.h>
#include <spark_wiring_i2c.h>

// HMC6343A I2C address is 19(25)
#define Addr 0x19

int xAccl = 0, yAccl = 0, zAccl = 0, xMag = 0, yMag = 0, zMag = 0;
void setup()
{
// Set variable
Particle.variable(“i2cdevice”, “HMC6343A”);
Particle.variable(“xAccl”, xAccl);
Particle.variable(“yAccl”, yAccl);
Particle.variable(“zAccl”, zAccl);
Particle.variable(“xMag”, xMag);
Particle.variable(“yMag”, yMag);
Particle.variable(“zMag”, zMag);

// Initialise I2C communication as MASTER
Wire.begin();
// Initialise Serial Communication, set baud rate = 9600
Serial.begin(9600);

// Start I2C Transmission
Wire.beginTransmission(Addr);
// Select Operational mode register 1
Wire.write(0x04);
// Set enable run mode and level orientation
Wire.write(0x11);
// Stop I2C Transmission
Wire.endTransmission();

// Start I2C Transmission
Wire.beginTransmission(Addr);
// Select Operational mode register 2
Wire.write(0x05);
// Set measuremnet rate 5 Hz
Wire.write(0x01);
// Stop I2C Transmission
Wire.endTransmission();
delay(300);

}

void loop()
{
unsigned int data[6];
for(int i = 0; i < 6; i++)
{
// Start I2C Transmission
Wire.beginTransmission(Addr);
// Select data register
Wire.write((64+i));
// Stop I2C Transmission
Wire.endTransmission();

    // Request 1 byte of data
    Wire.requestFrom(Addr, 1);
    
    // Read 6 bytes of data
    // xAccl msb, xAccl lsb, yAccl msb, yAccl lsb, zAccl msb, zAccl lsb
    if(Wire.available() == 1)
    {
        data[i] = Wire.read();
    }
    delay(300);
}


// Convert the data
xAccl = ((data[0] * 256) + data[1]);
if(xAccl > 32767)
{
    xAccl -= 65536;
}
yAccl = ((data[2] * 256) + data[3]);
if(yAccl > 32767)
{
    yAccl -= 65536;
}
zAccl = ((data[4] * 256) + data[5]);
if(zAccl > 32767)
{
    zAccl -= 65536;
}

for(int i = 0; i < 6; i++)
{
    // Start I2C Transmission
    Wire.beginTransmission(Addr);
    // Select data register
    Wire.write((69+i));
    // Stop I2C Transmission
    Wire.endTransmission();
    
    // Request 1 byte of data
    Wire.requestFrom(Addr, 1);
    
    // Read 6 bytes of data
    // xMag msb, xMag lsb, yMag msb, yMag lsb, zMag msb, zMag lsb
    if(Wire.available() == 1)
    {
        data[i] = Wire.read();
    }
    delay(300);
}


// Convert the data
xMag = ((data[0] * 256) + data[1]);
if(xMag > 32767)
{
    xMag -= 65536;
}
yMag = ((data[2] * 256) + data[3]);
if(yMag > 32767)
{
    yMag -= 65536;
}
zMag = ((data[4] * 256) + data[5]);
if(zMag > 32767)
{
    zMag -= 65536;
}

// Output data to dashboard
Particle.publish("Acceleration in X-Axis : ", String(xAccl));
delay(1000);
Particle.publish("Acceleration in Y-Axis : ", String(yAccl));
delay(1000);
Particle.publish("Acceleration in Z-Axis : ", String(zAccl));
delay(1000);
Particle.publish("Magnetic field in X-Axis : ", String(xMag));
delay(1000);
Particle.publish("Magnetic field in Y-Axis : ", String(yMag));
delay(1000);
Particle.publish("Magnetic filed in Z-Axis : ", String(zMag));
delay(1000);

}