Breakpoints

The step-by-step debugging feature is enabled by setting breakpoints in the source code of the application.

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• This feature is only available in DEBUG mode.
  See Set the Compilation Options.

Figure 1: Example: Breakpoints tab

• Breakpoints are a marker set in code which, when reached, stops the code's execution at that location.
  • This lets you run one step further in the program with stepping commands.
    
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• • Pausing a program does not interrupt the current VM cycle.
  • The current cycle finishes and execution is paused before the beginning of the next VM cycle.
• Breakpoints are shown as a red circle (dark or light) in the left margin.
• Breakpoints may be active () or inactive ().
  

Active or Inactive Breakpoints

• Breakpoints are active only when the KAS-IDE is connected to a target running an application that is compiled from the exact code displayed in the editor.
• Breakpoints are inactive if the KAS-IDE is:
  • Not connected to a target.
  • Connected but not running.
  • Connected to a different version of the code.
  • Connected to the code but a modification has been made in Edit mode.

Breakpoint Usage

• Breakpoints are always applied to the target, based on their position in the editor.
  • If a breakpoint is moved in the editor, and you reconnect to a target, the breakpoint in the target is moved to the new position.
• A Breakpoint that has been hit has a yellow triangle ( and ) to indicate it has been reached in the code.
• Breakpoints are saved when saving KAS and are reloaded when loading a KAS application.
• Projects support a maximum of 16 breakpoints.
  • This includes both enabled and disabled breakpoints.

See:

• Set, Remove, Enable, and Disable Breakpoints about working with breakpoints.
• Breakpoints tab about information in the Information and Logs widget.

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• • Breakpoints can significantly increase the PLC cycle time execution.
  • This is because the VM must evaluate the breakpoint condition at every cycle.

Online Change

• Online Change cannot be enabled when the KAS Runtime is paused due to a breakpoint.
  • Online Change can only be activated when the target is running. (Figure 2)

  

  Figure 2: Online Change message

• Every breakpoint is activated if an Online Change is performed successfully.

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• Breakpoints are not activated synchronously but in a reasonable time.

• All breakpoints become inactive when an Online Change is reverted.