Specifications

EssentialsofCrestronProgramming
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TheOneShotsymbolrespondstoarisingedgeonthe<trig>inputbydrivingtheoutput
signal(connectedto<out>)highforthedurationspecifiedbythedouble‐precision
<time>parameter.Theoutputsignalwillremainhighonlyforthisduration,regardless
ofwhatishappeningonthe<trig>input.Once<out>ha
sgonelow,thesymbolmaybe
re‐triggeredbyanotherrisingedge.Theoutput<out*>isthecomplementof<out>,just
aswesawwiththeTogglesymbol.
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OneShotalsohasa<reset>input.ThisinputallowsyoutocancelaOne‐Shotoperation
thatisalreadyinprogress.Thatis,on
cetheoutputpulsehasstarted,theonlywayto
cancelitbeforethefull<pulse_time>haselapsedisbydrivingthe<reset>inputhigh.
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ShownabovearetwoOneShot symbolsthataretriggeredoffbytheScreenUpand
ScreenDownbuttonpresses(s
inceonlyonerelaycanbeopenatatime),generatinga2‐
secondoutputpulsetodrivetherelaycommand.
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DrapesControl
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TheVirtualPresentationRoomusesasingle‐switch drapecontrollerforopeningand
closingthedrapes.Suchcontrollersoftenha
vealow‐voltagecontactclosureinterface:
closethecontactandthedrapesclose,openthecontactandthedrapesopen.Sincethe
touchpanelhastwobuttonsbeingroutedtoonerelay,weclearlyneedalatchingsignal
toconnecttotherelay.ASet/ResetLatchsymbolwillworkperfectlyfo
rthisapplication.
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TheSet/ResetLatchsymbolimplementsthemostbasicmemoryelement,alsoknownas
aset/resetflip‐flop.Thesymbolhastwopossiblestates,referredto(oddlyenough)asset
andreset.Arisingedgeofthe<set>inputwillsetthelatchandcause<ou
t>togohigh.
Oncethistransitionisseentheoutputwillnotchangeuntilarisingedgeisseenonthe