WDT的超时周期自动校正
TheWDTtimerisasimpleRCtimerwithatypical
time-outperiodofabout18ms.Thistime-outperiodis
dependentonVoltage,TemperatureandSiliconpro-
cessvariations.Hencethetoleranceonthetime-out
periodisverywide:Min.of9mstoaMax.of33ms
(pleaserefertoappropriatedatasheetfordevice
dependentvalue).Thereareapplicationswherean
additionaltimerwouldbeusefulasanapproximate
timekeeper,hencegettingamoreprecisevalueofthe
WDTtime-outisuseful.ThisTechBriefimplementsan
automaticcalibrationoftheWDTtime-outperiodon
start-up.TB004AutomaticCalibrationoftheWDTTime-outPeriodCONCLUSIONAuthor:StanD’SouzaAdvancedMicrocontrollerThecalibrationoftheWDTissimpleandtakesverylit-TechnologyDivisiontleoverheadinaprogram.ThecodeinAppendixAiswrittenforaPIC16C84device,butcanbetranslatedtoworkonanyPIC16CXXXproduct.ThecodeinAppendixBiswritt