PIC16F84A看门狗定时器测量温度

Almostalltemperaturesensorcircuitsusesomeform

ofdiscretecomponent(suchasathermistororasolid-

statesensor)toactuallymeasuretheenvironment’s

temperature.Itislefttothemicrocontrollertointerpret

thereadingintoahuman-friendlyformfortheuser’s

benefit.

Itispossible,however,todesignadigitalthermometer

withoutanexternalsensor,byusingatemperature

sensitivepropertyofthemicrocontrolleritself.This

ApplicationNoteshowshowtousetheWatchdog

Timer(WDT)ofaPICmicro

®

microcontrollerfortem-

peraturemeasurement.MAN828MeasuringTemperaturewiththePIC16F84AWatchdogTimerAuthor:LeenaChaudhariTHEORYOFOPERATIONMicrochipTechnologyInc.TheWDTonallPICmicromicrocontrollershasanomi-naltime-outperiodof18ms.TheWDTtime-outperiodvarieswithtemperature,VDDandpart-to-partprocessINTRODUCTION