Nmea-0183 outputs – Trimble Outdoors 5700/5800 User Manual
Page 168
A NMEA-0183 Output
1 56 5700/5800 GPS Receiver User Guide
5700/
5800 GPS Receiv
er Oper
ation
This appendix describes the formats of the subset of NMEA-0183
messages that are available for output by the receivers. For a copy of the
NMEA-0183 Standard, go to the National Marine Electronics
Association website at www.nmea.org.
A.1
NMEA-0183 Outputs
When NMEA-0183 output is enabled, a subset of NMEA-0183 messages
can be output to external instruments and equipment connected to the
5700 or 5800 serial ports. These NMEA-0183 messages let external
devices use selected data collected or computed by the GPS receiver.
All messages conform to the NMEA-0183 version 2.30 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 OR 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.
Table A.1 summarizes the set of NMEA messages supported by the
5700 and 5800 receivers, and shows the page where detailed
information about each message can be found.
Table A.1
NMEA message summary
Message
Function
Page
AVR
Time, yaw, tilt, range, mode, PDOP, and
number of SVs for Moving Baseline RTK
GGA
Time, position, and fix related data
GSA
GPS receiver operating mode
GST
Position error statistics