Chapter 9

Counters

Some of these options may not be available in some driver software.

Counter n Internal Output and Counter n TC Signals

Counter n TC is an internal signal that asserts when the counter value is 0.

The Counter n Internal Output signal changes in response to Counter n TC. The two software-selectable output options are pulse on TC and toggle output polarity on TC. The output polarity is software-selectable for both options.

Routing Counter n Internal Output to an Output

Terminal

You can route Counter n Internal Output to any PFI <4..7> or PFI <12..15> terminal.

Frequency Output Signal

The Frequency Output (FREQ OUT) signal is the output of the frequency output generator.

Routing Frequency Output to a Terminal

You can route Frequency Output to any PFI <4..7> or PFI <12..15> terminal.

Default Counter/Timer Pinouts

By default, NI-DAQmx routes the counter/timer inputs and outputs to the

PFI pins, shown in Tables 9-5and 9-6.

Table 9-5.Default NI-DAQmx Counter/Timer Pins for USB-6210/6211/6215 Devices

Counter/Timer Signal

Default Terminal Number (Name)

 

 

 

 

CTR 0 SRC

1 (PFI 0)

 

 

CTR 0 GATE

2 (PFI 1)

 

 

CTR 0 AUX

1 (PFI 0)

 

 

CTR 0 OUT

6 (PFI 4)

 

 

CTR 0 A

1 (PFI 0)

 

 

CTR 0 Z

3 (PFI 2)

 

 

© National Instruments Corporation

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NI USB-621x User Manual