I2C
https://github.com/adafruit/Adafruit_Sensor
https://github.com/adafruit/Adafruit_HMC5883_Unified es pot instal·lar directament des delgestor de llibreries
https://learn.adafruit.com/adafruit-hmc5883l-breakout-triple-axis-magnetometer-compass-sensor
https://www.adafruit.com/product/1746
1,20 €