KEELOQ®数据CRC校验程序

lloftheKEELOQEncoderssharethesamestandard

codewordformatcomposedofabasicsetof65bitsof

information.Although,theAdvancedEncoders(e.g.

HCS360,HCS361)supplementthatsetwithextrabits

ofinformationalongwithapairofCRCbits(Cyclic

RedundancyCheck).ThisTechnicalBriefpresentsa

routineinPICmicro

®

microcontroller(MCU)assembly

languagethatimplementstheCRCpolynomialasused

byAdvancedKEELOQEncodersandallowsaKEELOQ

receivertoverifythereceivedcodeword.TB043KEELOQCRCVerificationRoutinesAuthor:LucioDiJasioPICmicroMCUIMPLEMENTATIONMicrochipTechnologyInc.TheCRCcalculationwouldbeideallydoneontheflybythesameroutinethatisreceivingthedatafromtheOVERVIEWradioinput.Therefore,itwouldcomputeanewCRCvalueaseverydatabitgetsshiftedin.AfterreceivingAlloftheKEELOQEncoderssharet