The HMC5883L is a 3-axis magnetometer. The most common include usage of the chip is as a digital compass to sense direction or using them to detect ferrous metals.
/*
Analog input 4 I2C SDA
Analog input 5 I2C SCL
*/
Code
[c]
#include <Wire.h>
#define address 0x1E //I2C 7bit address of HMC5883
void setup(){
Serial.begin(9600);
Wire.begin();
//Put the HMC5883 IC into the correct operating mode
Wire.beginTransmission(address);
Wire.write(0x02);
Wire.write(0x00);
Wire.endTransmission();
}
void loop(){
int x,y,z
//begin reading data
Wire.beginTransmission(address);
Wire.write(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.read()<<8; //X msb
x |= Wire.read(); //X lsb
z = Wire.read()<<8; //Z msb
z |= Wire.read(); //Z lsb
y = Wire.read()<<8; //Y msb
y |= Wire.read(); //Y lsb
}
//Print out values of each axis
Serial.print(“x: “);
Serial.print(x);
Serial.print(” y: “);
Serial.print(y);
Serial.print(” z: “);
Serial.println(z);
delay(250);
}
[/c]
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