Toshiba nv Series - Chapter 3 Counter Function of the PI918; Operation of the Speed Counter

Chapter 3 Counter function of the PI918
6F8C1370
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3.2. Operation of the speed counter
Thespeedcountercontinuouslycountsinputpulses,andtransfersthe
countvaluetotheholdregisteratcertaincycles.  Thecountstarts
from"0."
Whenexternalinputpulsesareused,itcanbeusedasafrequency
counter.  Becausecountingisdonecontinuously,theabsolutevalueof
inputpulsecountcanbemeasured.
Wheninternalinputpulsesareused,itcanbeusedasaselfdiagnosis
counter.
Theinterruptstatusfunctionsetwiththealarmfunctioncanbeused. 
Interruptsduetothealarmvaluesettingofthespeedcounteroccurin
synchronizationwiththedataupdatecycleoftheholdregister.
Forthespeedcounter,gatecontrolwithgateinputandcommandis
invalid.
Someexampleapplicationsofthespeedcounterareprovidedbelow.