Pulse Train Generation; Continuous Pulse Train Generation - National Instruments PCI-6251 User Manual

Pulse Train Generation

Refer to the following sections for more information about the M Series pulse train generation
options:

Continuous Pulse Train Generation

•
Finite Pulse Train Generation
•
Continuous Pulse Train Generation
This function generates a train of pulses with programmable frequency and duty cycle. The
pulses appear on the Counter n Internal Output signal of the counter.
You can specify a delay from when the counter is armed to the beginning of the pulse train. The
delay is measured in terms of a number of active edges of the Source input.
You specify the high and low pulse widths of the output signal. The pulse widths are also
measured in terms of a number of active edges of the Source input. You also can specify the
active edge of the Source input (rising or falling).
The counter can begin the pulse train generation as soon as the counter is armed, or in response
to a hardware Start Trigger. You can route the Start Trigger to the Gate input of the counter.
You also can use the Gate input of the counter as a Pause Trigger (if it is not used as a Start
Trigger). The counter pauses pulse generation when the Pause Trigger is active.
Figure 7-25 shows a continuous pulse train generation (using the rising edge of Source).
SOURCE
Continuous pulse train generation is sometimes called frequency division. If the high and low
pulse widths of the output signal are M and N periods, then the frequency of the Counter n
Internal Output signal is equal to the frequency of the Source input divided by M + N.
For information about connecting counter signals, refer to the
section.
Figure 7-25. Continuous Pulse Train Generation
OUT
Counter Armed
M Series User Manual
Default Counter/Timer Pinouts
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