1. HMC5883L
TYWu

2. GY-271 HMC5883L Compass Module
Pictures

3. Other Versions 3 Axis Magnetometer - HMC5883L Breakout Board R2
Sparkfun Triple Axis Magnetometer Breakout - HMC5883L

4. HMC5883L
Block Diagram

5. HMC5883L 3-Axis Digital Compass IC
Use Honeywell’s Anisotropic Magnetoresistive (AMR) technology that provides advantages over other magnetic sensor technologies. These
12-Bit ADC Coupled with Low Noise AMR Sensors Achieves 5 milli-gauss Resolution in ±8 Gauss Fields
Low Voltage Operations (2.16 to 3.6V) and Low Power Consumption (100 μA)

6. HMC5883L
Specifications

7. HMC5883L
Specifications

8. Arduino Resource Example in WWW

9. Experiment Connection VCC 3.3V GND GND SCL A5 SDA A4
DRDY Floating

10. Experiment Arduino Code (Simple Version)
#include <Wire.h> //I2C Arduino Library
#define address 0x1E // b, I2C 7bit address of HMC5883
void setup(){
Serial.begin(9600);
Wire.begin();
//Put the HMC5883 IC into the correct operating mode
Wire.beginTransmission(address);
//open communication with HMC5883
Wire.send(0x02); //select mode register
Wire.send(0x00); //continuous measurement mode
Wire.endTransmission(); }

11. Experiment void loop(){ int x,y,z; //triple axis data
//Tell the HMC5883 where to begin reading data
Wire.beginTransmission(address);
Wire.send(0x03); //select register 3, X MSB register
Wire.endTransmission();
//Read data from each axis, 2 registers per axis
Wire.requestFrom(address, 6);
if(6<=Wire.available()){
x = Wire.receive()<<8; //X msb
x |= Wire.receive(); //X lsb
z = Wire.receive()<<8; //Z msb
z |= Wire.receive(); //Z lsb
y = Wire.receive()<<8; //Y msb
y |= Wire.receive(); //Y lsb }

12. Experiment //Print out values of each axis Serial.print("x: ");
Serial.print(" y: ");
Serial.print(y);
Serial.print(" z: ");
Serial.println(z);
delay(250); }

13. Experiment
Snapshot of
execution