Cliffs: Anyone know of a magnetic compass that works with the raspberry Pi, I2C and is 3.3V tolerant on the SDA/SCL? It may need to be tilt compensated. Please have first hand experience using it, I need it to work I cannot afford any more trial and error. Thanks!
Details:
I've had some serious issues with my quadcop_project in terms of getting heading. I've tried a mems sensor from xtrinsic but its not compatible via I2C with the Raspberry Pi 2. It works fine with RPi B+. I digress.
I have an HCM5883L breakout and realized its not 5V tolerant, I think I burned it up and the data doesn't make any sense to me. It is suppose to return a value between 0 and 255 but the registers are 16 bit with MSB and LSB being read independently.
https://www.sparkfun.com/products/10530
The examples from the Arduino don't make any sense. Its really simple to use:
https://www.sparkfun.com/tutorials/301
You can see the values they are getting there. A couple of odd things, the datasheet says it returns the data in 2 compliment form, which to me says I need to flip the bits but the sample code does not such thing.
Regardless, I am not sure how to use this because it has 3 axis! There is very little information on this board and no idea why I would want a 3 axis reading and how I would use that to calculate north.
