Digital Outputs Tab

Use the Digital Outputs tab to configure the digital output lines to use in an acquisition.

Complete the following steps to configure your digital output settings:

1. Click the Add Digital Output button to add a digital output to the Digital Outputs Summary Table.

   Tip  Click the Remove Digital Output button to remove a digital output from the Digital Outputs Summary Table.

2. Specify the Line to use for the digital output.
3. Specify an Action for the selected digital output line.
4. Complete one of the following sets of steps based on the selected Action.
   • Pulse Train, Single Pulse, or Rearmed Pulse. Refer to Pulse Types for more information on pulse types.
     1. Specify a Polarity to define the state of the pulse.
     2. Specify the Units to use for the Pulse Delay and Pulse Width controls. Units can be in milliseconds or Scaled Encoder counts.

        Note  Not all hardware supports scaled encoders.

     3. Specify a Pulse Delay as the desired duration of the first phase of the signal in timebase units. If the timebase units are Milliseconds, the Pulse Delay must be greater than 0. If the timebase units are scaled encoder, the minimum delay is one cycle.
     4. Specify a Pulse Width as the desired duration of the second phase of the signal in timebase units. If the timebase units are milliseconds, the Pulse Width must be greater than 0. If the timebase units are scaled encoder, the minimum delay is one cycle.
     5. Specify a trigger Source. A Source can be Immediate, a hardware line, or a Status Signal. When Immediate is selected, the pulse is driven when the acquisition begins. When a hardware line is selected, the pulse waits for the selected hardware line to have the selected polarity. When Status Signal is selected, the pulse waits for the selected status signal to have the selected polarity.

        Note  If the Source is Immediate, the Polarity and Signal settings do not apply. If the Source is a hardware line, the Signal setting does not apply.

     6. Select the Polarity of the trigger signal. The following options are avaialable:
        • Rising Edge
        • Falling Edge
     7. If the Source is Status Signal, select a Signal for the pulse trigger. The following Status Signals are supported: Acquisition in Progress, Acquisition Done, Frame Start, and Frame Done.

        Note  Frame Start and Frame Done are only valid for area scan cameras.

   • Drive Status Signal
     1. Specify a Polarity for the status signal.
     2. Specify a Status Signal to output. The following status signals are supported: Disabled, Acquisition in Progress, Acquisition Done, Unasserted, Asserted, Frame Start, Frame Done, Vertical Synchronization Signal, Horizontal Synchronization Signal, and Scaled Encoder. Frame Start, Frame Done, and Vertical Synchronization Signal only apply to Area scan cameras.

        Note  Scaled Encoder only applies to NI devices that support scaled encoders.