NMEA-GN-HDT

Description:

Standard NMEA: True heading. This message contains the actual vessel heading (from the Fusion solution) in degrees. “True” means the geometric North (not the magnetic North). Note that this is not the heading of motion (direction of travel) but the orientation of the sensor.

We recommend using the FP_A-ODOMETRY.orientation_* and FP_A-ODOMETRY.vel_* fields to calculate the heading of motion. See Appendix C to understand how to extract the heading from the FP_A-ODOMETRY message.

Configuration:

NMEA-GN-HDT_FUSION
NMEA-GP_HDT_FUSION
- Legacy message. This message also has GN constellation but the talker ID is “GP”

Notes:

These messages does not contain any information that would let one tell them apart. Do not enable more than one of these in the same port.
This message is according to NMEA 0183 v4.11 (and erratas).

Example message:

CODE

$GNHDT,61.7,T*05\r\n

Example message with non-standard high-precision fields:

CODE

$GNHDT,61.7183,T*3F\r\n

Message fields:

#	Field	Format	Unit	Nullable	Example	Description
1	`heading`	Float (.1/.4)	deg	Y	`61.7`	True heading
2	`true_ind`	Character	-	Y	`T`	Always `T`