magnetometer_sensor.ino

#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_LSM303_U.h>

/* Assign a unique ID to this sensor at the same time */
Adafruit_LSM303_Mag_Unified mag = Adafruit_LSM303_Mag_Unified(12345);
#define SERIAL_BAUD   115200

void displaySensorDetails(void)
{
  sensor_t sensor;
  mag.getSensor(&sensor);
  Serial.println("------------------------------------");
  Serial.print  ("Sensor:       "); Serial.println(sensor.name);
  Serial.print  ("Driver Ver:   "); Serial.println(sensor.version);
  Serial.print  ("Unique ID:    "); Serial.println(sensor.sensor_id);
  Serial.print  ("Max Value:    "); Serial.print(sensor.max_value); Serial.println(" uT");
  Serial.print  ("Min Value:    "); Serial.print(sensor.min_value); Serial.println(" uT");
  Serial.print  ("Resolution:   "); Serial.print(sensor.resolution); Serial.println(" uT");
  Serial.println("------------------------------------");
  Serial.println("");
  delay(500);
}

void setup(void)
{
#ifndef ESP8266
  while (!Serial);     // will pause Zero, Leonardo, etc until serial console opens
#endif
  Serial.begin(SERIAL_BAUD);
  Serial.println("Magnetometer Test"); Serial.println("");

  /* Enable auto-gain */
  mag.enableAutoRange(true);

  /* Initialise the sensor */
  if(!mag.begin())
  {
    /* There was a problem detecting the LSM303 ... check your connections */
    Serial.println("Ooops, no LSM303 detected ... Check your wiring!");
    while(1);
  }

  /* Display some basic information on this sensor */
  displaySensorDetails();
}

void loop(void)
{
  /* Get a new sensor event */
  sensors_event_t event;
  mag.getEvent(&event);

  /* Display the results (magnetic vector values are in micro-Tesla (uT)) */
  Serial.print("X: "); Serial.print(event.magnetic.x); Serial.print("  ");
  Serial.print("Y: "); Serial.print(event.magnetic.y); Serial.print("  ");
  Serial.print("Z: "); Serial.print(event.magnetic.z); Serial.print("  ");Serial.println("uT");

  /* Note: You can also get the raw (non unified values) for */
  /* the last data sample as follows. The .getEvent call populates */
  /* the raw values used below. */
  Serial.print("X Raw: "); Serial.print(mag.raw.x); Serial.print("  ");
  Serial.print("Y Raw: "); Serial.print(mag.raw.y); Serial.print("  ");
  Serial.print("Z Raw: "); Serial.print(mag.raw.z); Serial.println("");
  float heading = atan2(event.magnetic.y,event.magnetic.x)*180/3.14159;
  if(heading < 0)
    heading +=360;
  Serial.print("Magnetic North: "); Serial.println(heading);

  /* Delay before the next sample */
  delay(500);
}