Copyright (C) 2010 by Will Kamp <manimaul!gmail.com>
Published under the terms of "Simplified BSD License"
License text available in licence.txt

Turn two GPS antennas into a satellite compass

Supports: reading from most GPS devices
Requires: GPS that produce latitude, longitude as (RMC and GGA sentences) every 1 second or less
Outputs: Properly formated NMEA0183 HDT sentence