National Instruments Eight-slot USB Chassis NI cDAQ-9172 - Manual (Page 68)

NI cDAQ-9172 User Guide and Specifications 68 ni.com
Default Counter/Timer Routing
Counter/timer signals are available to correlated digital I/O C Series
modules in slots 5 and/or 6. To determine the signal routing options for
modules installed in your system, refer to the Device Routes tab in MAX.
Counter Triggering
Counters support three different triggering actions:
• Arm Start Trigger—to begin any counter input or output function, you
must first enable, or arm, the counter. Software can arm a counter or
configure counters to be armed on a hardware signal. Software calls
this hardware signal the Arm Start Trigger. Internally, software routes
the Arm Start Trigger to the Counter n HW Arm input of the counter.
For counter output operations, you can use the arm start trigger to have
start trigger-like behavior. The arm start trigger can be used for
synchronizing multiple counter input and output tasks.
• Start Trigger—for counter output operations, you can configure a start
trigger to begin a finite or continuous pulse generation. Once a
continuous generation triggers, the pulses continue to generate until
you stop the operation in software. For finite generations, the specified
number of pulses is generated and the generation stops unless you use
the retriggerable attribute. When you use this attribute, subsequent
start triggers cause the generation to restart.
When using a start trigger, the start trigger source routes to the
Counter n Gate signal input of the counter.
For counter input operations, the arm start trigger can imitate
trigger-like behavior.
• Pause Trigger—you can use pause triggers in edge counting and
continuous pulse generation applications. For edge counting
acquisitions, the counter stops counting edges while the external
trigger signal is low and resumes when the signal goes high or vice
versa. For continuous pulse generations, the counter stops generating
pulses while the external trigger signal is low and resumes when the
signal goes high or vice versa.
When using a pause trigger, the pause trigger source routes to the
Counter n Gate signal input of the counter.