TECDIS Installation Manual Page 40
When a given sensor provides more than one of the supported NMEA sentences, the highest
ranking option from the following lists (as applicable) should be used:
Position
1. $??GNS GNSS fix data
2. $??GGA GPS fix data
3. $??GLL Geographic position lat/long
4. $??RMC Recommended minimum specific GNSS data
5. !AIVDO * AIS own ship position. UAIS VHF Data link own-vessel report
Course & Speed
1. $??VTG Course and speed over ground
2. $??RMC Recommended minimum specific GNSS data
3. $??OSD Own ship data
4. !AIVDO AIS own ship position. UAIS VHF Data link own-vessel report
Heading
1. $??THS True heading and status
2. $??HDT Heading true
3. $??OSD Own ship data
4. $??VHW Water Speed and Heading
5. !AIVDO AIS own ship position. UAIS VHF Data link own-vessel report
Radar ARPA
$??TTM Tracked Target Message
Radar Cursor
$??RSD Radar System Data
AIS
!AI??? AIS UAIS VHF Data Link
Depth
1. $??DPT Depth
2. $??DBT Depth below transducer
* Position: !AIVDO may be used as a secondary position source whenever primary source is
missing.