We'll be demoing it with an Arduino but any other microcontroller can be used if you are willing to port the I2C code. We suggest using an Arduino to start since its guaranteed to work
- Connect VIN to 5V pin on the Arduino. If you have a 3V logic Arduino, connect VIN to 3V instead
- Connect GND to the ground pin on the Arduino
- Connect the SDA pin on the breakout to the I2C data SDA pin on your Arduino. On an UNO & '328 based Arduino, this is also known as A4, on a Mega it is also known as digital 20 and on a Leonardo/Micro, digital 2
- Connect the SCL pin on the breakout to the I2C clock SCL pin on your Arduino. On an UNO & '328 based Arduino, this is also known as A5, on a Mega it is also known as digital 21 and on a Leonardo/Micro, digital 3
Lucky for you we have written a very nice sensor library for the HMC5883L, which is based off of our Adafruit_Sensor framework library.
Open up the Arduino library manager:
Search for the Adafruit Sensor library and install it
Search for the Adafruit HMC5883 library and install it
We also have a great tutorial on Arduino library installation at:
Now, open the demo with
file -> examples -> Adafruit_HMC5883_U -> magsensor and upload it to your Arduino.