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Use the Breakpoint tool to place a breakpoint on a VI, node, or wire on the block diagram and pause execution at that location. When you set a breakpoint on a wire, execution pauses after data passes through the wire. Place a breakpoint on the block diagram to pause execution after all nodes on the block diagram execute.

When a VI pauses at a breakpoint, LabVIEW brings the block diagram to the front and uses a marquee to highlight the node or wire that contains the breakpoint. When you move the cursor over an existing breakpoint, the black area of the Breakpoint tool cursor appears white.

Placing Breakpoints

Complete the following steps to place a breakpoint on a VI, node, or wire on the block diagram and pause execution at that location.

1. Use the Breakpoint tool to click the wire or block diagram node where you want to pause execution. You also can right-click the wire or node and select Set Breakpoint from the shortcut menu.
2. Run the VI. When you reach a breakpoint during execution, the VI pauses and the Pause button appears red. The VI background and border begin flashing. You can take the following actions:
   • Single-step through execution using the single-stepping buttons.
   • Check intermediate values on probes that you placed on wires prior to running the VI.
   • Check intermediate values on probes that you place after running the VI if you have enabled the Retain Wire Values option.
   • Change values of front panel controls.
   • Click the Pause button to continue running to the next breakpoint or until the VI finishes running.

Removing Breakpoints

Use the Breakpoint tool to click an existing breakpoint to remove it. You also can right-click a breakpoint using the Positioning tool and select Clear Breakpoint to remove it. To remove all breakpoints in the VI hierarchy, select Edit»Remove Breakpoints from Hierarchy. You can select the Remove Breakpoints from Hierarchy option only in the Edit menu of a VI.

Note  You must manually remove breakpoints in dynamically called VIs or VIs referenced by the Static VI Reference function.

To locate and navigate all breakpoints on a block diagram, select Operate»Breakpoints and click the Find button on the Find dialog box that appears. The Search Results window lists all breakpoints in the VI. Double-click any item in the listbox to highlight the breakpoint on the block diagram.