This PIC16F628-based compass uses NMEA-0183 data from a GPS receiver. The direction indicator displayed on eight-point LED with radial pattern every 45°. Although the GPS provides accuracy to a tenth of a degree, that kind of accuracy is not really necessary in the automotive use for which project is designed.
To use the compass, user need to apply power to the GPS and to the display. After the GPS initializes, the display should show heading by illuminating one of the eight LEDs. If the GPS sends a “satellite warning flag” or if there is an RS232 framing (baud rate) error, or if data stops for over four seconds, the display will go dark. GPS Compass is designed by Jon Fick. Project schematic and source code.