Arduino Mega + HMC5883L compass
Digital 3-axis compass
Photo
I wanted the Ardunio to be able to detect the direction it is pointing - thus a compass. This module is not a Tilt Compensation Compass. For a yacht which heals, I thus do not recommend its use.
The Arduino Mega has pins 20 and pin 21 for the i2C SDA and SLC connectors.
Fritzing
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