NI C Series Getting Started

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 two-edge separation
measurement through the counter arm control. Aer the counter is armed, it waits
for the active edge on the first signal, and then it begins measuring the separation.
The measurement data is only ready and valid once the counter has finished
measuring the separation between the first and second edges. The counter returns a
value of zero prior to the first measurement becoming ready. Refer to your soware
documentation for more information on arming the counter.
Incremental Encoder Measurements
You can perform position and velocity measurements using incremental encoders
with the NI-9361, such as the quadrature and two-pulse encoders.
Quadrature Encoder Overview
A quadrature encoder can have up to three channels: A, B, and Z. When channel
A leads channel B in a quadrature cycle, the counter increments. When channel
B leads channel A in a quadrature cycle, the counter decrements. The amount of
increments and decrements per cycle depends on the type of encoding: X1, X2, or
X4.
X1 Encoding
The following figure shows a quadrature cycle and the resulting increments and
decrements for X1 encoding. When channel A leads channel B, the increment occurs
on the rising edge of channel A. When channel B leads channel A, the decrement
occurs on the falling edge of channel A.
Figure 19. X1 Encoding
Encoder Count 5 6 7 7 6 5
Ch A
Ch B
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NI-9361 Getting Started

NI C Series Specifications

General

Brand	NI
Model	C Series
Category	Control Unit
Language	English