digital compass modules

[Schmidt András]

Tilman Baumann wrote:
> Bluetooth would be nice. You would need no hardware hacks on the phone 
> itself.
> Should be pretty easy to hack a bluetooth->serial converter (like 
> BlueSMiRF from sparkfun) to the sensor. Maybe with a little 
> microcontroller glue in between.
> Bluetooth is very simple to code and simple to handle.
I was thinking about two possible applications:

   1. The map of a GPS map viewer application turns when you turn the
      machine so it is always aligned with the environment (this feature
      is included on some GPS tools.)
   2. A software rendered compass (I have already seen one on a phone as
      I mentioned in a previous mail)

Certainly these applications work best when the magnet sensor is fixed 
to the device itself :-). BT may work, but is an overkill. The I2C 
solution sugested by joerg and Robert Paulson seems to fit better.