使用PIC16C5X单片机解码红外遥控器

Formanyyearstheconsumerelectronicsindustryhas

beenemployinginfraredremotecontrolsforthecontrol

oftelevisions,VCR’s,andcableboxes.Thissametech-

nologyhasrecentlystartedtoappearinindustrialappli-

cationstoeliminatekeypads.

Decodingmostoftheinfraredsignalscanbeeasily

handledbyPIC16C5Xmicrocontrollers.Thisapplica-

tionnotedescribeshowthisdecodingmaybedone.

TheonlymandatoryhardwarefordecodingIRsignals

isaninfraredreceiver.Theuseoftwotypesis

describedhere.Botharemodulartypesusedoftenby

theconsumerelectronicsindustry.Thefirsttype

respondstoinfraredsignalsmodulatedatabout

40kHz.Thesecondrespondstonon-modulatedinfra-

redpulsesandhasarestrictedrange.Thehardware

costsofeachapproachwillbelessthantwodollars.

ThreePIC16C5Xapplicationprogramsaredescribed,

andinstructionsonhowtheycanbeusedtocreatean

algorithmthatcandecodejustaboutanyremotecon-

trolsignal.EachPIC16C5Xapplicationprogramrepre-

sentsastepinmappingoutapre-existinginfrared

format.Thefinalapplicationisafullyimplemented

exampleofdecodingandinterpretingtheinfraredsig-

nalsofatypeofTeknikaTVremote.AN657DecodingInfraredRemoteControlsUsingaPIC16C5XMicrocontrollerThemodulationlayerreferstothefactthateachburstAuthor:WilliamG.GrimmofinfraredsignalisoftenmodulatedatafrequencyConsultantbetween32.75kHzand56.8kHz.Thisisdonetodiminishtheeffectsofambientlight.Thislayer,how-ever,isoptional.Someinfraredformatsdonotmodu-INTRODUCTION