TW5340 User Manual
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©2014 -2015 Tallysman Wireless, Inc.
Confidential
10
NMEA Message Reference
NMEA 0183 sentences are all ASCII. Each sentence begins with a dollar sign ($) and ends
with a carriage return linefeed (<CR><LF>). Data is comma delimited. A checksum is
optionally added.
The first two letters following the „$” are the talker identifier. The next three characters
(sss) are the sentence identifier, followed by a number of data fields separated by
commas, followed by an optional checksum, and terminated by carriage return/line
feed. The data fields are uniquely defined for each sentence type.
RMC
Recommended Minimum Navigation Information
Fields
UTC Time
Status, V=Navigation receiver warning A=Valid
Latitude
N or S
Longitude
E or W
Speed over ground, knots
Track made good, degrees true
Date, ddmmyy
Magnetic Variation, degrees
E or W
FAA mode indicator (NMEA 2.3 and later)
Checksum
A status of V means the GPS has a valid fix that is below an internal quality threshold,
e.g. because the dilution of precision is too high or an elevation mask test failed.
