Measurement-computing DataShuttle Manual de usuario descargar pdf (Pagina 120)

14-6 Digital I/O

11-12-01

DataShuttle and DynaRes

If the gate interval is one second and pulses come in at the rate of 100 per second (100 Hertz frequency),

the resolution is 1% or 1 Hertz. If the gate interval is reduced to 0.1 second to measure the frequency, the

poorer the resolution.

Many applications require timing beyond the 32 milliseconds that one counter/timer can do with the

internal 2 megahertz clock. This requires the cascading of two counter/timers as was done with CT1 and

CT2. The first counter/timer, CT1, can be used to feed as many other counter/timers as desired. You can,

for instance connect CT1 to several counter/timers, each timing different intervals. CT1 becomes a time

base at a lower frequency than the built in 2 megahertz clock.

You can measure another frequency by adding only a single counter/timer and gating it with CT2. Just

connect the additional counter/timer gate input as well as the gate input of CT3 to the output of CT2. You

can gate almost an unlimited number of additional counter/timers, using only a single counter/timer for

each frequency measurement. The only limitation is that the time interval (gate interval) is the same for all

of them.

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Measurement-computing DataShuttle Manual de usuario Pagina 120