Trimble Outdoors Part Number 45005-00-ENG manual Nmea 0183 Communication Interface

NMEA 0183 C

C.1 The NMEA 0183 Communication Interface

NMEA 0183 allows a single source (talker) to transmit serial data over a single twisted wire pair to one or more receivers (listeners). The table below lists the characteristics of the NMEA 0183 data transmissions.

Table C-1	NMEA 0183 Characteristics
Signal Characteristic		NMEA Standard
Baud Rate		4800
Data Bits		8
Parity		None (Disabled)
Stop Bits		1

C.2 NMEA 0183 Message Format

The NMEA 0183 protocol covers a broad array of navigation data. This broad array of information is separated into discrete messages, which convey a specific set of information. The entire protocol encompasses over 50 messages, but only a sub-set of these messages apply to a GPS receiver like the Acutime 2000. The NMEA message structure is described below.

$IDMSG,D1,D2,D3,D4,.......,Dn*CS[CR][LF]

“$”	The “$” signifies the start of a message.
ID	The talker identification is a two-letter mnemonic
	that describes the source of the navigation
	information. The GP identification signifies a GPS
	source.
MSG	The message identification is a three-letter
	mnemonic that describes the message content and the
	number and order of the data fields.
“,”	Commas serve as delimiters for the data fields.

C-2 Acutime 2000 Synchronization Kit User Guide