Lassen SQ, Reference Manual

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Lassen SQ GPS Receiver 4 1
Software Interface 3
3.3.6
NMEA 0183 Protocol and Data Output Options
The National Marine Electronics Association (NMEA) protocol is an
industry standard data protocol which was developed for the marine
industry. Trimble has chosen to adhere stringently to the NMEA 0183
data specification as published by the NMEA. The Lassen SQ GPS
receiver also adheres to the NMEA 0183, Version 3.0 specification.
NMEA data is output in standard ASCII sentence formats. Message
identifiers are used to signify what data is contained in each sentence.
Data fields are separated by commas within the NMEA sentence. In
the Lassen SQ GPS receiver, NMEA is an output only protocol. The
NMEA protocol is described in detail in Appendix C.
The receiver is shipped from the factory with the TSIP protocol
configured on Port 1. The receiver can be reconfigured using TSIP
command packet 0xBC, in conjunction with TSIPCHAT, SQ_Monitor,
or a user written serial interface program.
The NMEA output messages selection and message output rate can be
set using TSIP command packet 0x7A. The default setting is to output
the GGA and VTG messages at a 1 second interval, when the receiver
output protocol is configured to NMEA, using packet 0xBC.
If NMEA is to be permanent for the application, the protocol
configuration (0xBC) and NMEA message output setting (0x7A) can
be stored in the non-volatile memory (on-board flash) using TSIP
command 0x8E-26.