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Aboutseriallines
ApreferredmethodtoestablishcommunicationbetweentheEK80andperipheraldevices,
isbymeansofseriallines.Severalseriallinestandardsareavailable,eachwithdifferent
qualities.
Unlessotherwisespecied,allseriallinecablesmustbeprovidedbytheinstallation
shipyard.
RS-232serialcommunication
AnRS-232serialportwasonceastandardfeatureofapersonalcomputer,usedfor
connectionstomodems,printers,mice,datastorage,uninterruptiblepowersupplies,
andotherperipheraldevices.However,RS-232ishamperedbylowtransmission
speed,largevoltageswing,andlargestandardconnectors.[...]Nevertheless,RS-232
devicesarestillused,especiallyinindustrialmachines,networkingequipmentand
scienticinstruments.
https://en.wikipedia.org/wiki/RS-232(September2015)
MostRS-232cablesdonotsupportallthesignalsinthestandardRS-232specication.
Important
WhenyouareusingRS-232serialcommunication,observethatlongrunsofunshielded
cablewillpickupnoiseeasily.ThisisbecausetheRS-232signalsarenotbalanced.
MaximumlengthforanRS-232serialcableistypically60meterswith2400bpsdata
rate,howeverthisdependsonthecablequality.Alwayscheckthecablemanufacturers
specicationsfortheactual"shuntcapacitance".Acommongureis47.5pF/m,which
givesamaximumcablelengthofabout50meters.
Note
EventhoughastandardexistforRS-232pinconguration,certainmanufacturermaystill
choosetheirownconnectorpinsforthevarioussignalsused.InordertomaketheRS-232
connectiontoyourperipheraldeviceworkproperly,youmustalwaysconsulttherelevant
instructionsprovidedbythedevicemanufacturer.
ForemoreinformationabouttheRS-232serialcommunicationstandard,see(forexample):
•https://en.wikipedia.org/wiki/RS-232
RS-422serialcommunication
WhileRS-232isthemostcommonserialinterfaceforcommunicatingwithexternaldevices
usingtheNMEAstandard,itonlyallowsforonetransmitterandonereceiveroneachline.
Cablelayoutandinterconnections