NI VeriStand 2018 Help
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As part of setting up an AI channel(s) to acquire waveforms, you specify the rate and size of acquisitions you want to perform, as well as other properties. You define these properties in a group, called a task, and you assign the task back to the AI channel(s). Tasks also define when the system starts and stops acquisitions and how to perform data logging.
Complete the following steps to configure timing properties, triggers, and logging in a task and assign the task to analog input channels:
- Select the Analog Input node under a DAQ device in the System Explorer configuration tree.
- Ensure the Sample Mode is set to Waveform.
- In the Analog Input Task menu, select Create new. This menu also contains any tasks already in the system definition.
- In the Create DAQ Task dialog box that displays, name the task and set basic timing properties.
When you click OK, NI VeriStand assigns the new task to the analog input channels in the system definition.
- Select the new task under the Waveform Tasks node in the configuration tree. The configuration tree appears similar to the following screenshot, where Task1 is the new task:
Configure how NI VeriStand performs waveform acquisitions using the following features in the configuration tree:
- Task configuration page—If you want the task to perform finite acquisitions, choose the size of each acquisition on this page. Identify an external sample clock, if desired.
- Logging page—If you want to log acquisitions, use this page to allow logging and configure how to save data in .tdms log files.
- Task Enabled channel—Use this channel to set whether the task is in an active, running state. Notice that enabling a task does not necessarily start acquiring samples. You might have specified triggering properties such that a waveform is not acquired until a trigger is detected.
- Triggers page—If you want acquisitions to start and stop when a certain analog or digital value occurs or a software command is received, define triggers on this page.
Overview: Acquiring Waveform Data from DAQ Devices
Timing Properties of Waveform Acquisitions
Features for Logging Waveform Data to Disk
Methods of Starting and Stopping Waveform Acquisitions
Waveform Task Channels