How do I interface another manufacturer's GPS to my Raymarine autopilot? Answer ID 225 | Published 07/30/2001 04:35 PM | Updated 08/03/2005 01:24 PM I have another manufacturer's GPS unit connected to my Raymarine autopilot by NMEA. When I set a "GOTO" waypoint on the GPS and call up the use of the "Auto...Track" instruction on the autopilot, the autopilot comes back and says "NO Data Available". Could you suggest what I should look at first? All of our current autopilots are directly NMEA compatible. The autopilot has a NMEA IN (+)and a NMEA IN (-). Some other manufacturers' GPS units have a slightly different NMEA wiring configuration with a NMEA IN (+), NMEA OUT (+), and a single ground wire which serves as the negative for NMEA IN, NMEA OUT, and Power. Connect the GPS units NMEA OUT (+) to the Raymarine pilot's NMEA IN (+). Then, to connect negative side, run a line from the Raymarine NMEA IN (-) to the GPS ground wire, or to ground. Some GPS units have a configurable NMEA Output. Make sure that it is set to output 4800 baud, NMEA 0183, and if selectable version 1.5 or higher.