Trimble Outdoors aggps 332 Benutzerhandbuch
AgGPS 332 GPS Receiver User Guide 79
NMEA-0183 Messages C
Each
NMEA
message includes:
•
an identifier to distinguish it from other messages in the data
stream
stream
•
one or more fields of data, separated by a comma
•
a checksum (preceded by *) to validate the data
Table C.1 explains the fields in the ZDA example shown in Figure C.1.
Fields 5 and 6 together give the total offset. Local time is 5 hours and
15 minutes earlier than
15 minutes earlier than
GMT
.
C2.1
Symbols and delimiters
All messages follow the
NMEA-0183
Version 2.1 format, in which
symbols and delimiters identify or separate the message data.
NMEA-0183
messages always:
•
begin with a dollar sign (
$
) followed by a talker ID code ( for
example GP) and a message
ID
code ( for example, ZDA)
•
end with a carriage return and line feed
Table C.1
Fields in an NMEA-0183 message — ZDA
Field
Data
Description
1
220320.0
Time in
UTC
2
26
Day (01 to 31)
3
06
Month (01 to 12)
4
1997
Year
5
-5
Local time zone offset from
GMT
(in hours
00 to ±13 hours)
6
15
Local time zone offset from
GMT
(in minutes)