In my quest for an accurate compass I found this - http://www.hitechnic.com/cgi-bin/commerce.cgi?preadd=action&key=NMC1034
The NXT Compass Sensor is a digital compass that measures the earth's magnetic field and outputs a value representing the current heading. The magnetic heading is calculated to the nearest 1° and returned as a number from 0 to 359. The NXT Magnetic Compass Sensor updates the heading 100 times per second.
From the documenation it seems like plain old I2C communication, so it should work fine with microcontrollers like the Axon. Anyone have any experience with hacking the NXT protocol? Any tips or tricks?
Or , does anyone know of a compass which has 1° accuracy that has a different interface?