National Instruments NI 1450 Series - Manual (Page 50)

Chapter 4 Digital I/O Functionality
© National Instruments Corporation 4-5 NI 1450 Series Compact Vision System User Manual
Figure 4-1 shows an output pulse when a trigger is selected.
Figure 4-1. Output Pulse When Trigger Is Selected
Pulse Modes
Each pulse generator has a Start and a Stop mode. Configure the pulse
generator when in Stop mode and then set it to Start mode.
Pulse Delay
Pulse delay is the amount of time between a trigger and the first (assertion)
edge of an output pulse. The pulse delay is configurable in units of
microseconds or quadrature encoder counts. If configured for
microseconds, available values are between 10
µs and 4,294,967,295 µs,
which is 4,294 seconds, or approximately 71 minutes. If the delay is
configured for quadrature encoder counts, the range of choices is 0 counts
to 4,294,967,295 counts.
Pulse Width
Pulse width is the amount of time between the first (assertion) edge of a
pulse and the second (deassertion) edge. Pulse width is configurable only
in microseconds from 10
µs to 4,294,967,295 µs.
Trigger Polarity
Each pulse generator can be individually configured for rising or falling
edge triggering. Even if multiple pulse generators are using the same
trigger, each can have different polarities.
Figure 4-2 shows the output of a pulse generator configured to look for a
rising edge trigger and output a high pulse with a microsecond width and
delay.
Output
Pulse
Trigger
Input