Simrad ST90 - Synchronization Using Clear to Send (CTS) and Request to Send (RTS) Signals

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•Thesystemsareallconnectedtoacommonsynchronizationsystem.
•Oneoftheacousticsystemsissetupas"master",andcontrolsthetransmissionson
theothersystems.
TheST90offersfunctionalityforremotetransmitsynchronization.Itcanbesetupto
operateineitherMasterorSlavemode.
Thefollowingsynchronizationmodesareavailable:
•Stand-alone
Synchronizationisturnedoff.ThissynchronizationmodeisusediftheST90is
workingbyitselfandwithnosynchronizationrequired.Thisisthedefaultsetting.
TheST90operatesusingitsinternalpingintervalparameters,independentofany
triggersignalsarrivingatthesynchronizationport.
TheSynchronizationDelaysettingisnotapplicablewhensynchronizationisswitched
off.
•Master
MastermodeisusediftheST90isgoingtoactasthecontrollingunitina
synchronizedsystem.Theperipheralhydroacousticsystem(s)areonlypermitted
totransmitwhenenabledbytheST90.WhenMastermodeisselected,theST90
willrunusingitsinternalpingintervalparametersandsendtriggersignalstothe
peripheralsystem(s).
•Slave
SlavemodeisusediftheST90isgoingtotransmitonlywhenpermittedbya
peripheralsystem.WhenSlavemodeisselected,theST90doesnottransmit("ping")
unlessanexternaltriggerappearsonthechosensynchronizationport.Theperipheral
systemmaybeanyotherhydroacousticproduct(forexampleanechosounderor
sonar),orevenadedicatedsynchronizationsystem.
Relatedtopics
Cabledrawingsandspecications,page206
SettinguptheST90inasynchronizedsystem,page199
SynchronizationusingClearToSend(CTS)andRequestTo
Send(RTS)signals
Inmanyapplications,thesynchronisationinterfaceisbasedonanRS-232serialport.
OnlytheCleartoSend(CTS)andRequesttoSend(RTS)connectionsoftheRS-232
interfacearethenused.
AccordingtothestandardspecicationsforRS-232,anoutputmustgenerateavoltage
levelof+5to+15VDC(logic"low"),and-5to-15VDC(logic"high")intoaloadof3
to7kΩ.AnRS-232receivermustpresenta3to7kΩload,convertinganinputof+3to
+25VDCtologic"low",andaninputof+3to+25VDCtologic"high".Withapositive
triggerpulse,theoffsetvoltagedoesnothaveanysignicance.Evensmallvariations
(utter)overandbelow0VDCwillnottriggertheinterface.
SimradST90InstallationManual