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Access this dialog box by double-clicking a transition node. You also can access this dialog box by right-clicking a transition node and selecting Configure Transition.

Use this dialog box to configure the trigger(s), guard, and/or action of a transition.

Note  LabVIEW disables the Triggers/Groups and Guard pages when you configure a transition node that leaves an Initial pseudostate.

• Label—Specifies the name of the transition or state. This name is for documentation purposes only and does not affect the execution of the statechart.
  
  Right-click the state border or transition node and select View»Label to see this label on the statechart diagram.
• Code Status—Displays a green checkmark if the Guard or Action code does not contain any errors. If LabVIEW detects an error in the code, this indicator updates to display a red X. Click this X to display the errors.
• Triggers/Groups—Use this page to specify a trigger or group of triggers that causes the statechart to begin evaluating this transition or static reaction. You can choose from triggers and groups that you have created.

  Note  You must specify at least one trigger for every transition and static reaction. Consider using the NULL trigger for transitions and static reactions in synchronous statecharts.

  • Edit Triggers and Groups—Launches the Edit Triggers and Groups dialog box, which you use to create and manage triggers and groups.
  • Select All Triggers—Specifies that any trigger in the Triggers list causes the statechart to begin evaluating this transition or static reaction.
  • Deselect All Triggers—Specifies that only the NULL trigger causes the statechart to begin evaluating this transition or static reaction.
• Guard—Use this page to write LabVIEW block diagram code that comprises the guard of the transition or static reaction. The statechart evaluates this guard after detecting a trigger or group you specify on the Triggers/Groups page. Specifying a guard is optional.
  
  The block diagram on this page is similar to a traditional LabVIEW block diagram. For example, you can access the Functions palette, call subVIs, and use probes. National Instruments recommends using subVIs to save space on this block diagram.
  
  You cannot access the front panel window for this block diagram, which means you cannot use front panel controls or indicators. To specify the value of a VI parameter, use a block diagram constant or input or state data..
  
  The left side of the block diagram contains two cluster elements. Click a cluster element to access a specific input, output, or state of the statechart. You can resize the cluster elements to access multiple elements simultaneously.

  Note  The Inputs cluster contains a special element, Inputs»StatechartStates»All Elements, which you use with the IsIn function.

  
  
  The right side of the block diagram contains the Execute? Boolean control. The guard code must send a TRUE or FALSE value to this Boolean control. If the guard code sends a TRUE value, LabVIEW executes any Action code associated with this this transition or static reaction. If the guard code sends a FALSE value, LabVIEW does not execute any action code.
  • Disable?—Prevents the statechart from executing the code on this block diagram. Place a checkmark in this checkbox to disable this code without erasing the code. Remove the checkmark from this checkbox to enable the code again.
• Action—Use this page to write block diagram code that describes any actions to take if the Guard evaluates to TRUE. You use this block diagram in the same way that you use the block diagram on the Guard page. Specifying an action is optional.

  Note  The Outputs cluster contains a special element, Outputs»InternalQueue»All Elements, which you use with the Send Internal Trigger function.

  This page has an additional cluster element on the right side of the block diagram. You use this cluster element to modify statechart output and/or state data.

  • Disable?—Prevents the statechart from executing the code on this block diagram. Place a checkmark in this checkbox to disable this code without erasing the code. Remove the checkmark from this checkbox to enable the code again.
• Documentation—Use this page to edit the name and description of the item you are modifying. This description is for documentation purposes only and does not affect the execution of the statechart.
  • Transition Name—Specifies the name of the transition.
  • Description—Specifies a description of the transition or static reaction.