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Chapter 3
Counter Input
Implicit Timing
With Implicit timing, the device measures the time between every pair of beginning and ending
events. The measurements are stored in a buffer. Each call to DAQmx Read returns values from
this buffer. Figure 3-25 shows an example of Implicit timing.
Figure 3-25.
Two-Edge Separation Measurement: Implicit Timing
To use Implicit timing, use the DAQmx Timing (Implicit) VI or function.
Sample Clock
With Sample Clock timing, on each active edge of the sample clock, the device stores one
measurement. The one measurement is the time between the most recent pair of beginning and
ending events to occur before the sample clock. Figure 3-26 shows an example of Sample Clock
timing.
Figure 3-26.
Two-Edge Separation Measurement: Sample Clock Timing
To use Sample Clock timing, use the DAQmx Timing (Sample Clock) VI or function.
Trigger Settings
By default, the counter begins measuring when software calls DAQmx Start Task. You can
change this behaviors by setting DAQmx Trigger properties.
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