Building Run LabVIEW VI Steps from a Template

Note You must use LabVIEW 7.1 or later to create a VI you can run from the Run LabVIEW VI step. You cannot run a VI that was saved for a previous version of LabVIEW using the Run LabVIEW VI step. You must save the VI in the actual version of LabVIEW you want to run.

The LabVIEW SignalExpress steps have four execution states. In LabVIEW, open UserDefinedStepTemplate.vi in the SignalExpress\User Step Templates directory. The UserDefinedStepTemplate VI contains a Case structure with four cases. Each case represents one of the four execution states. The following list describes each case:

• Configure—Executes once as the first case each time you click the Run button in LabVIEW SignalExpress.
• Reconfigure—Executes when you change parameter values on a Run LabVIEW VI step while the project is running.
• Run—Executes repeatedly or once after the Configure case executes, depending on the run mode you use to run the project. Place indicators for data you acquire in this case.
• Stop—Executes once after you click the Stop button or select the Abort option in LabVIEW SignalExpress.

Note  The _Event enumerated type control on the front panel of the template VI is connected to the connector pane and wired to the selector terminal of the Case structure on the block diagram. Removing or renaming this control breaks the template VI.

If you need to share data between execution cases, use a shift register on the While Loop that surrounds the Case structure. Notice that a Boolean constant wired to the While Loop condition node is set to TRUE. This forces code in the While Loop to execute once every time LabVIEW SignalExpress calls the Run LabVIEW VI step. You only need to use a While Loop if you use shift registers to share data between execution cases.