User Guide

NI cDAQ-9172 User Guide and Specifications 66 ni.com
Routing a Signal to Counter n Aux
Each counter has independent input selectors for the Counter n Aux signal.
You can route the following signals to the Counter n Aux input:
• Any PFI terminal
• ai/ReferenceTrigger
• ai/StartTrigger
• Analog Comparison Event
In addition, you can route Counter 1 Internal Output, Counter 1 Gate,
Counter 1 Source, or Counter 0 Gate to Counter 0 Aux. You can also
route Counter 0 Internal Output, Counter 0 Gate, Counter 0 Source, or
Counter 1 Gate to Counter 1 Aux.
Some of these options may not be available in some driver software.
Counter n A, Counter n B, and Counter n Z Signals
Counter n B can control the direction of counting in edge counting
applications. Use the A, B, and Z inputs to each counter when measuring
quadrature encoders or measuring two pulse encoders.
Routing Signals to A, B, and Z Counter Inputs
Each counter has independent input selectors for each of the A, B, and Z
inputs. You can route the following signals to each input:
• Any PFI terminal
• Analog Comparison Event
Routing Counter n Z Signal to an Output Terminal
You can route Counter n Z to any output PFI terminal.
Counter n Up_Down Signal
Counter n Up_Down is another name for the Counter n B signal.
Counter n HW Arm Signal
The Counter n HW Arm signal enables a counter to begin an input or output
function.
To begin any counter input or output function, you must first enable,
or arm, the counter. In some applications, such as buffered semi-period
measurement, the counter begins counting when armed. In other
applications, such as single pulse-width measurement, the counter begins