Specifications
EssentialsofCrestronProgramming
66
Feedback
Buttonfeedbackdescribesthebuttonʹsactiveappearance.Forkeypads,feedbackis
usuallyindicatedwithaLEDlocatedinsidethebuttonhousing.Fortouchpanels,
feedbackcanvary,andoftenincludeschangingtheframeandtextcolor,alongwitha
simulated3Dappearance.IntheTPS‐15‐G‐QMproject,thePowerbutton’stextlabel
changescolor,andthe3Dappearan
ceinverts.
Visual Button Feedback
Feedbackisvitallyimportanttoagooduserinterfacedesign.Foronething,feedback
letstheuserknowthatabuttonpresshasregisteredwiththesystem.Thisisespecially
importantfortouchpanels,wheretheusercannottellfromfeelalonewhetherthey
pressedintherightspot.
Anotherpurposefeedbackservesistoprovideinformationtotheuserab
outthecurrent
stateofthesystem(thattheDVDiscurrentlyinPLAYmode,forexample).Inthiscase,
careshouldbetakentomakethefeedbackbeasaccurateaspossible,asinaccurateor
vaguefeedbackwillonlyservetoconfusetheuser.
Whetherab
uttonispressedornotisdeterminedbytheuser(ortheuserʹsfingertobe
exact!)butitisa signalthatdecideswhetherabuttonisshowninitsfeedbackstateor
not.Therefore,thesignalisthedrivingforceforthebuttonf
eedback.Wherethesignal
comesfromdependsuponwhattypeoffeedbackisneeded.
Themostbasictypeoffeedbackiscalledmomentaryfeedback.Momentaryfeedback
causesthebuttontodisplayinitsfeedbackstateonlywhenthebuttonitselfispressed.
Thistypeoffeedbackmakessenseforfunctionsthatoccuronlywhilethebutton is
pressed.Forexample,volumeupan
dvolumedownbuttonstypicallyreceive
momentaryfeedbackbecausethevolumelevelonlychanges(goesupordown)while
thecorrespondingbuttonispressed.
Momentaryfeedbackcanbeachievedsimplybyconnectingthebuttonpresssignal
nametothefeedbacksignalforthesa
mebutton,asshowninthediagrambelow.