As mentioned above, you do not send a route to the autopilot. The route is in the chartplotter
, OpenCPN) and you send the current
waypoint, bearing, distance, cross track error, etc. to the autopilot. You do not need any converters, just connect the nmea output from CPN to the nmea input on the ST60+.
There is also no useful information that you can take from the autopilot to OpenCPN, so you do not need the reverse connection. Now, if you have other Seatalk data such as depth
or speed, then you need a Seatalk to nmea converter to be able to use/display that. In most cases though, it is cheaper to display the data on the autopilot head