Specifications

EssentialsofCrestronProgramming
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76
SourceSelectionFeedback
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TheprogrammingforsourceselectionfeedbackutilizesanInterlock‐Togglesymbol,
whichincorporatesInterlockandTogglefunctionsinonesymbol.Thisisnecessary
becauseeachsourceselectbuttonwilltogglethecorrespondingtransportcontrol
subpageopenandclosed.Atthesametime,thebuttonsneedtobeinterlockedsothat
onlyonesubpagecanbeactiveaton
etime.TheInterlock‐Togglesymbolaccomplishes
thisbecauseittogglesthestateofagivenoutputhighandlowwitheachrisingedgeof
thecorrespondinginput,andalsointerlockstheoutputssothatonlyoneoutputcanbe
highatonetim
e(breakbeforemake).
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Arisingedgeofthe<clear>inputimmediatelyforcesalloutputstozero.Thesignal
attachedtothisinputispartofthePowerOffeventandwillbediscussedlater.
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SerialI/O
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Uponselectingasource,thetouchpanelwilldisplayamessageindicatingthecurrently
selectedsource.Thestringisupdatedduringruntimeastheselectedso
urcechanges.
TheSIMPLprogramwillutilizetheSerialI/Osymboltosendstringsdynamicallytothe
touchpanel.
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Asseenintheexample,eachofthesourceselectionbuttonpresseshasbeenroutedtoan
<in>inputontheSerialI/Osymbol.Ontherisingedgeofaninput,thecorresponding
string(indicatedintheparameterfield)willbetransmittedon<tx$>.The<tx$>outputis