Installation manual

Telegramformats
AbouttheNMEAtelegramformat
TheSimradES70cansendandreceiveinformationtoandfromseveraldifferent
peripherals.Alltransmissionstakeplaceastelegramswithdatasentences.Each
telegramhasadenedformatandlength.
TheNMEA0183standardisthemostcommonprotocolusedtoreceiveandtransmitdata
toandfromperipheralsensors.AparametricsentencestructureisusedforallNMEA
data.Thesentencestartwitha“$”delimiter,andrepresentthemajorityofapproved
sentencesdenedbythestandard.Thissentencestructure,withdelimitedanddened
datales,isthepreferredmethodforconveyinginformation.
Thefollowingprovidesasummaryexplanationoftheapprovedparametricsentence
structure.
$aaccc,c—c*hh<CR><LF>
FormoreinformationabouttheNMEAstandard,theformatandthedatasentences,refer
totheirofcialpublications.TheirdocumentNMEA1083-Standardforinterfacing
marineelectronicdevicesexplainstheformatsindetail.Thedocumentcanbeobtained
fromh
t t p : / / w w w . n m e a . o r g .
Note
InsometelegramsreceivedfromotherSimradequipments,the$characterisreplacedby
the@character .Thechecksumeldmaythennotbeinuse.
1“$”:Startofsentence(Hex:24).
2aaccc:Addresseld.Thersttwocharacters(aa)identiestheTalkerID,while
thelastthreecharactersaretheSentenceformattermnemoniccodeidentifyingthe
datatypeandthestringformatofthesuccessiveelds.
3“,”:Fielddelimiter(Hex:2C).Thischaracterstartseacheldexcepttheaddress
andchecksumelds.Ifitisfollowedbyanulleld,itisallthatremainstoindicate
nodataintheeld.
4c—c:Datasentenceblock.Thisisaseriesofdataeldscontainingallthedatatobe
transmitted.ThedataeldsentenceisxedandidentiedbytheSentenceformatter
intheaddresseld.Dataeldsmaybeofvariablelengths,andtheyarepreceded
bytheFielddelimiter.
5“*”:Checksumdelimiter(Hex:2A).Thisdelimiterfollowsthelasteldofthe
sentence,andindicatesthatthefollowingtwoalphanumericalcharacterscontain
thechecksum.
6hh:Checksum
7<CR><LF>:Terminatessentence
DBSDepthbelowsurface
Thistelegramcontainsvesselheadingindegreesmagnetic.Thetelegramisnolonger
recommendedforuseinnewdesigns.
ItisoftenreplacedbytheDPTtelegram.
343522/A
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