NI C Series Getting Started

Figure 11. Pulse Measurement
Counter
Armed
Pulse High
Pulse
Low
Pulse
Low
Pulse
High
Counter
Read
Counter
Read
Signal to Measure
Counter Timebase
Counter Value 0 1 2 3 1 2 1 2 1 1 1 2
Current Measurement
Read Value
3 3 2
3 2
1 1 22 2 1
1 2
Pulse High Time: 3 * Counter Timebase Period = 30 ns
Pulse Low Time: 2 * Counter Timebase Period = 20 ns
Signal Period: Pulse High Time + Pulse Low Time = 50 ns
Duty Cycle: Pulse High Time / Signal Period = 0.6
Channel Settings
You can configure the following counter properties:
■
Input terminal of the signal-to-measure.
■
The active edge, rising or falling, the NI-9361 begins the measurement.
■
Maximum measurable period.
■
You can set the maximum measurable period of the signal. If the input
signal period is slower 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 previous measurements. To
disable this feature, set the maximum measurable period to zero. When this
feature is disabled, the counter keeps measuring until a valid measurement
is detected, the counter overflows, or the user stops the counter.
Trigger Settings
Counter Arm—You can control when the counter starts the pulse measurement
through the counter arm control. Aer the counter is armed, it waits for the active
edge on the signal-to-measure, and then it begins measuring the signal high and
low times. The measurement data is only ready and valid once the counter has
finished measuring the first signal period. The counter returns a value of zero for
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NI-9361 Getting Started

NI C Series Specifications

General

Brand	NI
Model	C Series
Category	Control Unit
Language	English