As I wait for replacement parts from Digikey (smoked a processor), I started to play with a magnetic compass. This unit has a serial interface. It took me quite a while to figure out/remember that you can’t connect a serial device to the TX/RX lines of an Arduino and both program and use the serial port for the compass without connecting and disconnecting the compass. To get past this hurtle, I moved the compass to other pins and used the SoftwareSerial library from Arduino V1.0. Not too shabby.
By the end of my play hour, I had the compass up and running and providing 4Hz updates. Tonight I hope to start logging this data to look for magnetic shifts that are occurring due to solar storms. I subscribe to the NOAA space weather updates and get an email at least once a week warning of magnetic storms. Will be interesting to see if a consumer compass can see the shifts that are logged by scientists with special building sized magnetometers.