Creating Probes after a VI Runs
You can configure a VI to retain wire values so that when you create a probe on the block diagram, the probe displays the data that flowed through the wire at the last VI execution. Click the Retain Wire Values button to save the wire values at each point in the flow of execution so that when you place a probe on a wire, you can immediately obtain the most recent value of the data that passed through the wire. You must successfully run the VI at least once before you can collect data from any wires using probes. Using probes after a VI runs is useful when the block diagram is complex and you want to debug the VI.
Complete the following steps to create a probe after a VI runs.
- Click the Retain Wire Values button
on the block diagram toolbar to retain wire values for use with probes.
- Run the VI. The VI must execute at least once so that wire values can be available immediately to any probes you create.
- Stop the VI.
- Place a probe on a wire by right-clicking the wire and selecting Probe. Notice that the most recent value of the data that passed through the wire appears in the subpanel of the Probe Watch Window.
Click the Do Not Retain Wire Values button 
at any time to refrain from saving wire values at each execution.
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Note Choose the Do Not Retain Wire Values option to reduce memory requirements and improve performance slightly. |