How to Generate a Pulse using an NI-IMAQ I/O Device

Use the Generate Pulse (NI-IMAQ I/O) step to configure digital pulse generation on NI CVS-1450 Series Compact Vision System and NI PCI-8254R/PCIe-8255R IEEE 1394 interface devices with reconfigurable I/O. The Generate Pulse (NI-IMAQ I/O) step starts pulse generation, but the step does not wait until a pulse finishes before continuing the inspection.

1. In the Step Name control, enter a descriptive name for the step.
2. In the Pulse Settings table, select the digital output line you want to configure.
3. In the Action control, specify the behavior you want for the selected digital output line and complete one of the following sets of steps to configure the digital output line:
   • Do not Update—Performs no action on the digital output line when the step is run. Select this option if you do not want to use the selected digital output line or if you do not want to change the operation because the line is being used by another Generate Pulse (NI-IMAQ I/O) or Read/Write I/O (NI-IMAQ I/O) step in the inspection.
   • Generate Single Pulse—Configures the selected digital output line to generate a single pulse. Complete the following steps to configure the single pulse:
     1. Specify the Polarity for the pulse.
     2. Specify a Delay and Timebase for the pulse.
     3. Specify the Width of the pulse.
     4. In the Single Pulse Settings control, select whether you want the pulse to Always pulse when this step runs or Pulse when this step runs AND a specified condition is met. If you select the Pulse when this step runs AND option, you must also specify a Measurement and value to use to determine if the single pulse is generated when the step runs.
   • Start/Stop Pulse Generation—Configures the selected digital output line to generate continuous pulses. Complete the following steps to configure the pulse train:
     1. Specify the Polarity for the pulse.
     2. Specify a Delay and Timebase for the pulse.
     3. Specify the Width of the pulse.
     4. In the Continuous Pulse Settings control, select whether you want the pulse to be an Immediate Pulse or a Triggered Pulse. If you select Immediate Pulse, a pulse train starts when the step executes. If you select Triggered Pulse, a single pulse occurs every time the state of the selected trigger line has the specified polarity.
4. Repeat steps 2 and 3 to configure additional pulses.
5. Click Apply to preview the pulse generation settings.
6. Click OK to add the step to the inspection.