NI C Series Getting Started

measurement becoming ready. Refer to your soware documentation for more
information on arming the counter.
Two-Edge Separation Measurement
You can take two-edge separation measurements with the NI-9361 on CompactRIO
systems only.
The counter measures the time between two events. The beginning event is an
active edge on a first signal. The ending event is an active edge on a second signal.
The NI-9361 returns the current time between the two events in the number of ticks
of the 100 MHz counter timebase when the counter is read. The following figure
shows an example of two-edge separation measurement.
Figure 18. Two-Edge Separation
0 0 0 0 1 2 3 4 5 6 87
Counter
Armed
Counter
Read
First Signal
Second Signal
Counter Timebase
Counter Value
Current Measurement
Read Value
8
8
Measured Interval
Channel Settings
You can configure the following counter properties:
■
Input terminal of the first signal.
■
Input terminal of the second signal.
■
The active edge of the first signal, rising or falling, the NI-9361 begins the
measurement.
■
The active edge of the second signal, rising or falling, the NI-9361 ends the
measurement.
■
Maximum measurable separation—You can set the maximum measurable
separation of the signals. If separation time between the first and second
signals is longer than this value, the counter returns a measurement value of
zero. Use this property to get updated measurement data when the signal
slows down or is stopped instead of returning previous measurements. To
disable this feature, set the maximum measurable separation to zero. When
© National Instruments
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NI-9361 Getting Started

NI C Series Specifications

General

Brand	NI
Model	C Series
Category	Control Unit
Language	English