MP875 Modem User Guide
56 2130808
GPS protocols and commandsNote: The “MP 3G Modems
TAIP Reference manual”
(document #2130312) provides
a description of the TAIP
commands that can be used with
the MP modem. This is available
at www.sierrawireless.com.
Information about Trimble GPS
modules, including more
documentation on TAIP
commands, is available at
www.trimble.com.
More information on NMEA
message standards is available
at www.nmea.org.
TheGPSmodulesupportstwomethodsofreportingnaviga‐
tionalinformation,usingeithertheTAIP(TrimbleASCII
InterfaceProtocol)orNMEA(NationalMarineElectronics
Association)protocols.TheGPSmoduleispre‐configuredfor
TAIP.IfyouareusingaGPSapplicationthatrequiresdatato
bereportedaccordingtotheNMEAprotocol,theMPmodem
mustbereconfiguredusinganATcommand.(SeetheMP3G
ModemsATCommandReferencemanual(document#2130810.)
NMEAisareportingprotocolonly,whileTAIPprovidesthe
abilitytosendcommandstothemoduletoqueryforinfor‐
mationandconfigurereports.WhentheMPmodemissetfor
TAIP,commandscanbesenttotheMPmodemintheseways:
•Using3GWatch er
•UsingATcommands
TAIPcommandscanbeusedto:
•QuerytheMPmodemforitscurrentposition,heading,
andspeed
•EnableanddisableautomaticreportingofGPSdata,and
settheintervalatwhichautomaticreportsaresent
•Configuretheformatofreports
GPS display in 3G WatcherToview3GWatc her’s GPSDisplaywindow,whichreports
latitude,longitude,speed,direction,altitude,andlocaland
UTCtime1,selectTools > Display GPSordouble‐clicktheGPS
icononthemain3GWatch erwindow.
Fromacoldstart(wheretheMPmodemispoweredonwith
nostorednavigationaldata),itmaytakeupto39secondsfor
theGPSmoduletoobtainsatellitefixesandbeginreporting.
1. UTCreplacesGreenwichMeanTimeasthebasisfor
standardtimethroughouttheworld.UTC,whichuses
atomicmeasurementsratherthantheEarth’srotation,is
theequivalentofmeansolartimeattheprimemeridian
(0°longitude).