ThePIC16C5Xhasone8-bittimer(Timer0),whichcan
beusedwithan8-bitprescaler.Theprescalerruns
asynchronously,henceitcancountaveryhigh
frequency.Theminimumriseandfalltimesoftheinput
frequencyarespecifiedtobe10ns,sothefastestclock
ratetheTMR0cancountis50MHz.Theprescalermust
beusedwhenmeasuringhighfrequency.Sincethe
prescalercanbeconfiguredasadivideby256counter,
themaximumresolutionatwhichtheinputfrequency
canbemeasuredis16-bits.However,theprescaler
cannotbedirectlyreadlikeafileregister.Thisapplica-
tionnotedepictsauniquemethodbywhichtheuser
can“extract”the8-bitvalueintheprescaler,whereby
theresolutionofthemeasurementis16-bitswiththe
high8-bitsinTMR0andthelow8-bitsintheprescaler.AN592FrequencyCounterUsingPIC16C5XTMR0isconguredtomeasuretheinputfrequency,atAuthor:StanD’SouzaT0CKIofthePIC16C54.Theinputfrequencyis“gated”MicrochipTechnologyInc.foraprecisedurationoftime.Beforestartingthispre-cise“gate”,TMR0iscleared(whichalsoclearstheINTRODUCTIONprescaler),andtheRA2pinisconguredasaninput.Theprecise“gate”is
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