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1、EnhancedCaptureTimerModule ReferenceManual ECT 16B8CBlockUserGuide EnhancedCaptureTimer16bbufferedReg 8b counter ECTHardwareOverview A16 bitmasterup counter A16 bitmodulusdown counter withprogrammableprescaler 8independenttimerchannels eachcapableofinputcaptureandoutputcomparefunctions 4x8 bitpulsea
2、ccumulatorswhichmaybeconfiguredas2x16 bitpulseaccumulators TIMERSTRUCTURE PRE SCALERPR 2 0 MainClock 1248163264128 TCNT 15 0 DATABUS PAPULSEAccumulator PIN R R R R 1 CLOCKSCOUNTERENABLE0 CLOCKSCOUNTERDISABLE TENTSWAITSFRZTFFCA TSCR1 TIMERSYSTEMCONTROLREGISTER RST 00000000 TCNTCLK TEN B0 B7B8 B15 R R
3、eserved 0006 AddressOffset 0004 05 TOF Timer PrescalerandCounter 1 TCNT 2 TFLG2 TimerOverflowFlagWritea 1 toclear 16BITFREERUNNING MODULOCOUNTER PRESCALER SELECTION 1 TIMEROVERFLOWINTERRUPTENABLE0 TIMEROVERFLOWINTERRUPTDISABLE TOF0000000 B7 B0 B15 B0 REGISTERS RST 00000000 RST 0 0 000F 000D AddressO
4、ffset 0004 0005 3 TSCR2 RST 00000000 1 TIMERRESETBYOC7MATCH0 COUNTERISFREERUNING TCRE ALLOWSFORPULSEWIDTHMODULATIONFUNCTION B7 B0 TOI000TCREPR2PR1PR0 TIMEROPERATION USEFULFOR 1 BASISFORALLTHETIMINGFUNCTIONS 2 PROVIDINGTIMEINFORMATIONTOPROGRAMS DESCRIPTION THEE CLOCKDRIVESAPRESCALER DIVIDEBY1 T0128 W
5、HICHINTURNDRIVESA16BITCOUNTER WHENTHETIMERGOESFROM FFFFTO 0000 THETIMEROVERFLOWFLAGBITISSETINADDITION ANOVERFLOWINTERRUPTMAYOCCUR RESETCONDITIONS TCNTISINITIALIZEDTOALLZEROESANDDisabled TIMEROVERFLOWINTERRUPTSAREDisabledTC7 TC0REGISTERSARECLEARED TIMEROVERFLOWFLAGISCLEARED PRESCALERIS1 INTERRUPT FOR
6、TIMEROVERFLOW TOCLEARINTERRUPTWRITE1TOTOFBITTFLG2 DONOTUSEBITMANIPULATIONINSTRUCTIONS SINCERM WOPERATION TIMEROVERFLOWVECTORUSED TimerOverflowInterrupt OutputCompareFunction Compare CaptureUnit16 BitFree RunningCounter 16 BitOutputCompareRegister programmedbysoftware PinControlLogic InterruptRequest
7、toCPU OCxF StatusFlagissetuponcomparematch OCxI OptionalLocalInterruptMask Enabledthroughsoftware UPTO8separateOutputCompareFunctions EachOutputCompareFunctionhasitsownVectorandControls Providesamechanismtooutputasignalataspecifictime Actiontakenuponmatchofcompareregisterwithcounter TCNT TOCx PinOCx
8、 Comparator MATCH OutputCompare OC7 OC0 1of4 USEFULFOR 1 OUTPUTWAVEFORMCONTROL SOFTWARECONTROLLED 2 ELAPSEDTIMEINDICATOR TOEXTERNALCIRCUITRY DESCRIPTION DURINGEACHE CLOCKCYCLE THEOUTPUTCOMPARE REGISTERSARECOMPAREDTOTHEFREE RUNNING COUNTER IFTHEREISACOMPARETHEN 1 THEINTERRUPTFLAGBITISSET INADDITION E
9、ITHERORBOTHOFTHEFOLLOWINGMAY OCCUR 1 THESTATEOFTHEASSOCIATEDOUTPUTPINMAYBECHANGED 2 ANINTERRUPTISGENERATEDTOCPU IFEnabled OutputCompare 2of4 C7FC6FC5FC4FC3FC2FC1FC0F C7IC6IC5IC4IC3IC2IC1IC0I OM7 OL7 OM6 OL6 OM5 OL5 OM4 OL4 1 TC7 TC0 2 TFLG1 3 TIE 4 TCTL1 COMPARE CAPTUREFLAGSWrite 1 toClearInterruptF
10、lag COMPARE CAPTUREMASK0 InterruptRequestMasked1 InterruptRequestEnabled OUTPUTMODEAND OUTPUTLEVEL O7 OC0 REGISTERS OM3 OL3 OM2 OL2 OM1 OL1 OM0 OL0 5 TCTL2 RST 00000000 0008 RST 00000000 RST 00000000 RST 00000000 000C 000E 0009 AddressOffset 0010 0011 001E 001F ForceOutputCompare 3of4 FOC7FOC6FOC5FO
11、C4FOC3FOC2FOC1FOC0 5 CFORC B7B6B5B4B3B2B1B0 FORCEOUTPUTCOMPARE PINS 1 OC7 OC0 PORTTPINS7 0 USEDTOSTABLISHINITIALTIMERPINSTATES NOTE FORCEOUTPUTCOMPAREDOESNOTSETOCxFLAGS FORCEOUTPUTCOMPARE7MAYAFFECTANYORALLOUTPUTCOMPAREPINS RST 00000000 0001 OutputCompare OC7 OC0 4of4 INTERRUPTS FOROUTPUTCOMPARES OC7
12、 OC0 TOCLEARINTERRUPT WRITE1TOOCxFBITINTFLG1 DONOTUSEBITMANIPULATIONINSTRUCTIONS SINCERM WOPERATION OC7 OC0VECTORSAREUSED RESETCONDITIONS FREERUNNINGCOUNTER TCNT INITIALIZEDTO 0000ANDDisabled OutputCompare OC7 1of2 CONTROLOFMULTIPLEOUTPUTCOMPAREPINS CONTROLOFASINGLEPINBYTWOOUTPUTCOMPARES THUS SHORTP
13、ULSESAREPOSSIBLE DURINGEACHE CLOCKCYCLE THEOUTPUTCOMPARE REGISTER1ISCOMPAREDTOTHEFREE RUNNING COUNTER IFTHEREISACOMPARETHEN INADDITION EITHERORBOTHOFTHEFOLLOWINGMAY OCCUR 1 THEINTERRUPTFLAGBITISSET 1 THESTATEOFOUTPUTPINSOC7 OC0 MAYBECHANGED 2 ANINTERRUPTMAYOCCUR USEFULFOR DESCRIPTION 1 2 OC7CANAFFEC
14、TMULTIPLEPINS OC7 OC0 OC7ACTIONOVERRIDESANYCONFLICTINGOC7 OC0ACTION FORAGIVENPIN OutputCompare7 2of2 C7IC6FC5FC4FC3FC2FC1FC0F OC7M7OC7M6OC7M5OC7M4OC7M3OC7M2OC7M1OC7M0 4 TIE TIMERINTERRUPTENABLE 5 OC7M OC7MASK B7 B0 1 TC7 16BITCOMPAREREGISTER7 RST 00000000 RST 00000000 0002 000C C7FC6FC5FC4FC3FC2FC1F
15、C0F RST 00000000 000E B7 B0 2 TCNT 16 BITTIMER B15 B0 RST 0 0 0004 05 B7 B0 3 TFLG1 TIMERFLAG1 OC7D7OC7D6OC7D5OC7D4OC7D3OC7D2OC7D1OC7D0 6 OC7D OC7DATA RST 00000000 0003 B7 B0 OutputCompare7FlowChart COUNTER ANDOUTPUT COMPAREREG MATCH 1ST ECYCLE FORTHIS COUNTER VALUE WRITEBIT TOFOC7 START SET OC7F OC
16、7I 1 ASSERT INTERRUPT 0 0 1 1 0 1 0 1 0 0 1 1 0 1 0 1 END DRIVEOC7 PINLOW DRIVEOC7 PINHIGH Y N OC7M7 OC7D7 OC7M0 OC7D0 DRIVEOC0 PINLOW DRIVEOC0 PINHIGH N N Y Y OutputCompareFlowChart Complete COUNTER ANDOUTPUT COMPAREREG MATCH 1ST ECYCLE FORTHIS COUNTER VALUE WRITEBIT TOFOCx START SET OCxF OCxI 1 ASSERT INTERRUPT 0 0 1 1 0 1 0 1 END DRIVEOCx PINLOW DRIVEOCx PINHIGH Y N OC7Mx OC7Dx DRIVEOCx PINLOW DRIVEOCx PINHIGH N N Y Y OC7 ASSERTED THISE CYCLE N TOGGLE OCxPIN Y FOROCx OC7 OC0 n TimerToggleonOv
