Autohelm Inboard Autopilots (ST6000 and ST7000 systems) Service ...

Autohelmmessage indicates the ST6000 is receiving data recognised as NMEA but has aninvalid flag set. This is normally due to the receiver having a low signal strength or ahigh noise figure.5.4 Autohelm 6000 NMEA 0183 data input formatThe 6000 must receive Cross Track Error data at least once every 30seconds.If a display of Waypoint Bearing, Distance or Number or the Waypointadvance facility is required then this information must be received atleast once every 30 seconds.All NMEA data is read into a buffer thus enabling the 6000 to copewith delays between characters and delays between sentences.All Talker identifier characters, ie RA, DE, LC etc. are ignored allowinginterface with any type of equipment so long as the sentence type isone of the following :-Apparent wind speed and angle can be received from any external equipmenttransmitting the N.M.E.A VWR header. The ST6000 will only display apparent windangle but will convert and retransmit both apparent wind speed and direction on theseatalk bus. This information can then be displayed on an ST50 wind instrumentacting as a repeater.TrackControlBearing toWaypointDistance toWaypointWaypointNumberApparent WindSpeed and DirectionXTE APB WDR APB VWRXTR BPI WDC APAAPA BWR BPI BPIAPB BWC BWR BWRRMB BER BWC WDRBEC BER BWCRMB BEC WDCRMBRMBBODWCVBERBEC20SeaTalk Service Manual