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.
The following table summarizes the set of NMEA messages supported by the receiver.
Message |
Function |
---|---|
GNSS satellite fault detection (RAIM support) |
|
Time, position, and fix related data |
|
Position data: position fix, time of position fix, and status |
|
GNS |
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 |
|
Time, position, position type, and DOP values |
|
Time, position, position type, and DOP values |
|
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 |
|
ZDA |
UTC day, month, and year, and local time zone offset |
To enable or disable the output of individual NMEA messages, do one of the following:
-
Create an application file in the Configuration Toolbox software that contains NMEA output settings and then send the file to the receiver.
-
Add NMEA outputs in the Serial outputs tab of the GPS Configurator software and then apply the settings.
For SPS Modular receivers, you cannot use the GPS Configuration software to load application files to the receiver. You must set up the NMEA output using the keypad and display or a web browser.
For a copy of the NMEA-0183 Standard, go to the National Marine Electronics Association website at www.nmea.org.