The HMC5883L is a triple-axis magnetometer compass, which uses I2C for communication.
Compass heading accuracy of 1° to 2°, provided by internal 12-bit ADC (Analog-to-Digital Converter).
The module includes on-board pull-up resistors on the I2C lines.
There is a data ready pin (pin DRDY) you can use to make your communication with the module more efficient; refer to the datasheet below for details.
Since this module has such great compass heading accuracy, it is great for giving your robot precise navigation abilities.
Module Power supply: 3~5v
Communication: I2C communication protocol
Max Data Rate: 160 Hz
Heading accuracy: 1° – 2°
Measuring range: ± 1.3 – 8 gauss
Size (mm): 18.2 * 13.3 * 2.2