Contents
Counter n A, Counter n B, and Counter n Z Signals ......................................
9-28
Routing Signals to A, B, and Z Counter Inputs................................
Counter n Up_Down Signal............................................................................
Counter n HW Arm Signal..............................................................................
Routing Signals to Counter n HW Arm Input ..................................
Counter n Internal Output and Counter n TC Signals.....................................
9-29
Routing Counter n Internal Output to an Output Terminal ..............
Frequency Output Signal ................................................................................
Routing Frequency Output to a Terminal.........................................
Default Counter/Timer Pinouts .....................................................................................
Counter Triggering ........................................................................................................
9-31
Arm Start Trigger............................................................................................
Start Trigger ....................................................................................................
Pause Trigger ..................................................................................................
Other Counter Features..................................................................................................
9-32
Sample Clock ..................................................................................................
Cascading Counters.........................................................................................
9-33
Counter Filters.................................................................................................
Prescaling ........................................................................................................
9-34
Duplicate Count Prevention ............................................................................
9-35
Example Application That Works Correctly
(No Duplicate Counting) ...............................................................
9-36
Example Application That Works Incorrectly
(Duplicate Counting) .....................................................................
9-37
Example Application That Prevents Duplicate Count......................
Enabling Duplicate Count Prevention in NI-DAQmx......................
9-38
Chapter 10
PFI
Using PFI Terminals as Timing Input Signals ..............................................................
10-2
Exporting Timing Output Signals Using PFI Terminals...............................................
10-3
Using PFI Terminals as Static Digital I/Os ...................................................................
Connecting PFI Input Signals........................................................................................
PFI Filters ......................................................................................................................
10-4
I/O Protection ................................................................................................................
10-6
Programmable Power-Up States....................................................................................
NI USB-621x User Manual
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