This project is a PIC18F252-based repeater for GPS data. It is intended to connect to hand held GPS receivers that don’t have external antennas such as Garmin-38. The aim of the repeater is to allow the GPS to be placed outside, exposed to the satellite view, and allow the user to see the data below decks at the navigation station. The gps repeater displays several pages of data pertaining to both the GPS and the boat electrical system on LCD display. A DB-9 jack is on the front panel for the purposes of connection of a laptop to upload and download GPS waypoint data, etc.
The project features : interfaces for Garmin GPSMAP 172C (both Garmin and NMEA protocols); USB interface to connect a laptop to either Garmin or NMEA bus; Seatalk® interface for Raytheon instruments (speed, depth, autopilot); battery voltage interface; diesel tachometer interface. The project is designed by Jon Fick. Project C code and schematic