Editing Counter (digital) (section)

===Frequency counter===

Some counter applications utilize multiple counters. An example of this is the [[frequency counter]] shown below, which uses two counters to measure the frequency of a digital signal. One counter, configured as a one-shot, produces a pulse of precisely controlled width known as the ''time gate''. The time gate is used to enable the clocking of an event counter, which is clocked by the signal whose frequency is to be measured.

[[File:Basic frequency counter.jpg|500px|border|Frequency counter]]

When a measurement begins (by asserting ''Start''), the event counter is zeroed and then proceeds to count rising edges of the unknown frequency signal while the time gate remains active. When the time gate ends, edge counting stops and the accumulated count indicates the measured frequency. The count directly indicates the measured frequency in Hz when the gate time is one second; for other gate times, the count must be scaled to obtain Hz.