NMEA-0183 messages: Overview
When NMEA-0183 output is enabled, a subset of NMEA-0183 messages can be output to external instruments and equipment connected to the receiver serial ports. These NMEA-0183 messages let external devices use selected data collected or computed by the GNSS receiver.
All messages conform to the NMEA-0183 version 3.01 format. All begin with $ and end with a carriage return and a line feed. Data fields follow comma (,) delimiters and are variable in length. Null fields still follow comma (,) delimiters, but contain no information.
An asterisk (*) delimiter and checksum value follow the last field of data contained in an NMEA-0183 message. The checksum is the 8-bit exclusive of all characters in the message, including the commas between fields, but not including the $ and asterisk delimiters. The hexadecimal result is converted to two ASCII characters (0–9, A–F). The most significant character appears first.
NMEA messages are in a ASCII-based format.
The following table summarizes the set of NMEA messages supported by the receiver.
Message |
Function |
---|---|
Dynamic positioning |
|
Datum reference information |
|
GNSS satellite fault detection (RAIM support) |
|
Time, position, and fix related data |
|
Position data: position fix, time of position fix, and status |
|
GNS Fix data |
|
GRS range residuals |
|
GPS DOP and active satellites |
|
Position error statistics |
|
Number of SVs in view, PRN, elevation, azimuth, and SNR |
|
Heading from True North |
|
Leica local position and quality |
|
MSK receiver signal |
|
Time, yaw, tilt, range, mode, PDOP, and number of SVs for Moving Baseline RTK |
|
Base station position and position quality indicator |
|
L-band corrections and beacon signal strength and related information |
|
Event marker data |
|
Time, position, position type, and DOP values |
|
Time, position, position type, and DOP values |
|
Projection type |
|
Rover Extended output |
|
Time, locator vector, type, and DOP values |
|
Heading Information |
|
Position, Velocity, and Time |
|
Rate of turn |
|
Actual track made good and speed over ground |
|
UTC day, month, and year, and local time zone offset |
To enable or disable the output of individual NMEA messages:
-
In the receiver web interface, select I/O Configuration. Choose the required port to output NMEA messages.
-
Select NMEA as the output message type and then enable or disable individual NMEA messages as required.
For a copy of the NMEA-0183 Standard, go to the National Marine Electronics Association website at www.nmea.org.