stan wrote:
The question, somewhat inarticulate when written, is not whether it
should be done, for that should be simple, but what will it do for the
4000, for the wind meter, etc. Will new information become viewable on
the 4000 control screen?

Does anyone see any distinct advantage in hard wiring a Raymarine RC400
Chartplotter to a Raymarine 4000 autopilot?

The sophistication of what you can get has increased over time with the
advancement from "Autohelm 4000" (no screen) and "Autohelm ST4000"
(single line LCD) to "Autohelm ST4000+" (multi line LCD).

The original 4000 has no NMEA or Seatalk capability.

The ST4000 has NMEA input and a Seatalk port. From the ST4000 up you can
activate a waypoint or route on the chartplotter which your autopilot
will be able to follow the line towards that waypoint. This is called
"track" mode. I suggest you look this up in the manual.

The main advantage over keeping a magnetic heading is that it
compensates for leeway and current.

The ST4000+ also has the capability to display additional data, such as
(from a GPS/Chartplotter) UTC time, GPS location, distance/bearing to
waypoint, Speed over Ground (SOG), and from other Seatalk units: Depth,
Speed through water, etc.

--
Kees