[Al Skierkiewicz]

Kelli,
We had looked into using a compass on a few occassions. The ones we were looking at (and I am guessing this one as well) reguire a rather large current pulse or pulses to help calibrate and restore operation. The I2C reference is a car serial control protocol as I remember. Perhaps someone from the auto makers could elaborate on this. We had trouble working with our prototype depending on the building structure. Although we were able to get usable data in most locations, we didn't want to depend on arena variables to prevent us from doing a good auto mode. FYI so you don't get too discouraged, we spent some long hours trying to debug the compass while working on a stainless steel conference room table. Rack that up to late hours at the end of the build. It took us a while to realize where the error was coming from.

See http://www.robot-electronics.co.uk/h...he_i2c_bus.htm