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

GBS

GNSS satellite fault detection (RAIM support)

GGA

Time, position, and fix related data

GLL

Position data: position fix, time of position fix, and status

GNS

GNS Fix data

GRS

GRS range residuals

GSA

GPS DOP and active satellites

GST

Position error statistics

GSV

Number of SVs in view, PRN, elevation, azimuth, and SNR

HDT

Heading from True North

LLQ

Leica local position and quality

MSS

MSK receiver signal

PASHR

Proprietary roll and pitch sentence

PTNL,AVR

Time, yaw, tilt, range, mode, PDOP, and number of SVs for Moving Baseline RTK

PTNL,BPQ

Base station position and position quality indicator

PTNL,DG

L-band corrections and beacon signal strength and related information

PTNL,GGK

Time, position, position type, and DOP values

PTNL,PJK

Time, position, position type, and DOP values

PTNL,REX

Rover Extended output

PTNL,VGK

Time, locator vector, type, and DOP values

PTNL,VHD

Heading Information

RMC

Position, Velocity, and Time

ROT

Rate of turn

VTG

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.