Compass sensor, this compass module has been specifically designed for use in robots as an aid to navigation, the aim was to produce a unique number to represent the direction the robot is facing, 5V working voltage, 20mA current, 0.1° resolution, I2C interface.
Produces a unique number to represent an orientational direction
Two Philips KMZ512 magnetic field sensors (which are sensitive enough to detect the Earth's magnetic field) are mounted at right angles to compute the direction of the horizontal component of the Earth's magnetic field
The output bearing can be obtained from a PWM signal on pin 4 or via the I²C bus on pins 2 and 3
The PWM signal is a pulse width modulated signal with the positive width of the pulse representing the angle
The pulse width varies from 1ms (0°) to 36.99ms (359.9°) – that is 100µs/° with a +1ms offset
Works well; I am quite new to electronics but got it working on a Picaxe microcontroller in about 30 minutes. This was my first ever I2C project too. I have seen cheaper units out there, but am not sure if they would work as well. This unit has to be kept flat to work, some higher spec ones can compensate for being tilted and remain accurate.
