Raspberry Pi 3 + CMPS14 compass

Example code of connecting the Raspberry Pi v3 to a CMPS14 compass. The compass is a tilt compensated compass which is great for a boat that heels. The compass power and signal/logic levels appear to be 3.3v to 5v tolerant which is good when learning.

A bit of an issue communicating between the Raspberry Pi and the CMPS14 compass. The CMPS14 might be using the allowed i2c clock-stretching to keep up with the Raspberry Pi, but available i2c libraries don't take this into account. I have thus had to manage the i2c communication in software. Which is slower and because it is slower, now probably doesn't need the clock-stretching.