My E-120 has a mode where you can display raw data received from the NMEA
, Seatalk2 (NMEA-2000) and HSB2 (IP over Ethernet) ports
. I just skimmed through the C-120 manual downloaded from Raymarine, and didn't see a similar feature for it - but it still may be buried somewhere.
Assuming your autopilot is physically connected, you can see if it is sending any data to the chartplotter
. If not, then the first thing to check out is whether the cable is properly connected, and whether it's properly wired.
Finally, you need to make sure the chartplotter
is sending the proper sentences to the autopilot. My Raymarine S3G looks for cross track error (APB or XTE), bearing to waypoint (BWC), heading (HDG/HDT/HDM), among others. If your autopilot is NMEA-only (not Seatalk-capable), you'll probably have to configure your chartplotter to output via the NMEA
port the proper sentences. It's in the manual...