Originally Posted by Waterman480
Drawing E shows GPS/XTE data going from the BT adapter to the baudrate converter - however the line from the GX2150 to the BT adapter contains only AIS/DSC data not GPS/XTE data - so you are missing something there...
No, the autopilot needs waypoint, XTE, SOG, etc. to run in track mode. That needs so come from a chartplotter/GPS combination. In my schematic, these sentences are transmitted by OpenCPN from the Netbook through Bluetooth to the autopilot. AIS has nothing to do with this. The AIS sentences go the other way through Bluetooth so that OpenCPN can plot the traffic.