AppendixETelegramformats
GLLGeographicalposition
latitude/longitude
Thistelegramisusedtotransferlatitudeandlongitudeofvessel
position,timeofpositionxandstatusfromaglobalpositioning
system(GPS).
$--GLL,llll.ll,a,yyyyy.yy,a,
hhmmss.ss,A,a*hh<CR><LF>
•GLL=telegramidentier.
•llll.ll,a=latitudenorth/south,positionindegrees,minutes
andhundredths.CharactersN(North)orS(South)identies
thebearing.
•yyyyy.yy,a=longitudeeast/west,positionindegrees,minutes
andhundredths.CharactersW(West)orE(East)identies
thebearing.
•hhmmss.ss=coordinateduniversaltime(UTC)ofposition.
•A=status,charactersA(datavalid)orV(datanotvalid)
areused.
•a=modeindicator.
HDMHeading,magnetic
Thistelegramcontainsvesselheadingindegreesmagnetic.The
telegramisnolongerrecommendedforuseinnewdesigns.Itis
oftenreplacedbytheHDGtelegram.
$--HDM,x.x,M*hh<CR><LF>
•HDM=telegramidentier
•x.x=headingindegrees,magnetic
HDTHeading,true
Thistelegramisusedtotransferheadinginformationfromagyro.
$--HDT,x.x,T*hh<CR><LF>
•HDT=telegramidentier
•x.x,T=heading,degreestrue
MWDWinddirectionandspeed
Thistelegramprovidesthedirectionfromwhichthewindblows
acrosstheearth’ssurface,withrespecttonorth,aswellasthe
speedofthewind.
$--MWD,x.x,T,y.y,M,z.z,N,s.s,M*hh<CR><LF>
307531/C
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