Trimble Outdoors AgGPS 332 - Manual (Page 89)

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
• 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
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)