HT67F4892 datasheet(89/188 Pages) HOLTEK

89 / 188 page

Rev. 1.00

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Rev. 1.00

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HT67F4892

Enhanced A/D Flash MCU with LCD & EEPROM

HT67F4892

Enhanced A/D Flash MCU with LCD & EEPROM

Capture Input Mode

ToselectthismodebitsTnM1andTnM0intheTMnC1registershouldbesetto01respectively.

Thismodeenablesexternalsignalstocaptureandstorethepresentvalueoftheinternalcounter

andcanthereforebeusedforapplicationssuchaspulsewidthmeasurements.Theexternalsignalis

suppliedontheTPn_0,TPn_1orTCKnpinwhichisselectedusingtheTnCAPTSbitintheTMnC1

edges;theactiveedgetransitiontypeisselectedusingtheTnIO1andTnIO0bitsintheTMnC1

theapplicationprogram.

WhentherequirededgetransitionappearsontheTPn_0,TPn_1orTCKnpinthepresentvaluein

thecounterwillbelatchedintotheCCRAregistersandaTMinterruptgenerated.Irrespectiveof

whateventsoccurontheTPn_0,TPn_1orTCKnpin,thecounterwillcontinuetofreerununtilthe

TnONbitchangesfromhightolow.WhenaCCRPcomparematchoccursthecounterwillreset

backtozero;inthiswaytheCCRPvaluecanbeusedtocontrolthemaximumcountervalue.When

aCCRPcomparematchoccursfromComparatorP,aTMinterruptwillalsobegenerated.Counting

thenumberofoverflowinterruptsignalsfromtheCCRPcanbeausefulmethodinmeasuringlong

pulsewidths.TheTnIO1andTnIO0bitscanselecttheactivetriggeredgeontheTPn_0,TPn_1

orTCKnpintobearisingedge,fallingedgeorbothedgetypes.IftheTnIO1andTnIO0bitsare

bothsethigh,thennocaptureoperationwilltakeplaceirrespectiveofwhathappensontheTPn_0,

TPn_1orTCKnpin,howeveritmustbenotedthatthecounterwillcontinuetorun.

AstheTPn_0,TPn_1orTCKnpinispinsharedwithotherfunctions,caremustbetakeniftheTM

isintheCaptureInputMode.Thisisbecauseifthepinissetupasanoutput,thenanytransitionson

thispinmaycauseaninputcaptureoperationtobeexecuted.TheTnCCLR,TnOCandTnPOLbits

arenotusedinthisMode.

HT67F4892 Datasheet(PDF) 89 Page - Holtek Semiconductor Inc