Pausing and Resuming Programs
You can pause and resume programs from the Configuration Editor or DPL Editor.
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Note: |
On SM-Applications and SM-Applications Lite it is only possible to pause or resume a program if the node properties have requested that debug information is embedded in the program. |
To pause or resume a program from within the Configuration Editor
In the Hardware Architecture view, select the node for which to stop or start the program and do one of the following:
From the Run menu, choose Pause/Resume Program.
On the main toolbar press
To pause or resume a program from within the DPL Editor
Do one of the following:
From the Run menu, choose Pause/ Resume Program.
On the main toolbar press
To pause or resume a node DPL program from the task manager within the DPL editor
In the task manager, press
See Also
Controlling Program Execution
Debugging Applications
Editing the Properties of Nodes
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Stopping and Stepping Tasks
Stepping a task means executing a single line of code in the task at a time. However, before stepping a task, you need to pause execution of the task. When execution of a task has been paused you can choose to continue normal execution of the task.
To stop or step a task from the DPL editor
1. In the main DPL view, place the cursor in the task to stop.
2. From the Run menu, choose Stop/Step Task.
To stop or step a task from the task manager within the DPL editor
In the task manager, select the task to stop or step, then press
When a task is running, it stops (or sleeps). When a task is stepped, the next line in the program is executed, then the task stops again.
The following picture shows a Background task stopped in the DPL editor. The status of the task is shown as Sleeping in the Task Manager and a yellow arrow is shown in the left column of the DPL showing the line which will be executed next if the task is stepped or resumed.
If the task is stepped once as described above by selecting Stop/ Step Task from the Run menu, the line a% = a% + 1will be executed and the DPL editor will look like:
See Also
Running Tasks
Controlling Program Execution
Debugging Applications
Using Breakpoints
Tasks
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Running Tasks
Within active programs, you can run specific tasks after having stopped them. You run tasks from within an active program in the DPL Editor or the Task Manager.
To run a stopped task from the DPL editor
1. In the program, place the cursor in the task to run.
2. From the Run menu, choose Run Task.
To run a stopped task from the task manager
In the task manager, select the task to run, then press
The task resumes execution. Execution will continue until either a breakpoint is hit or the task is stopped.
See Also
Stopping and Stepping Tasks
Controlling Program Execution
Debugging Applications
Using Breakpoints
Tasks
Using Breakpoints
While in on-line mode, breakpoints enable you to interrupt, i.e. stop, the execution of a task in a program prior to execution of a specific line of code. Breakpoints can only be set in tasks and only one breakpoint can be set per task.
Once a breakpoint is reached, you can choose to perform many operations:
Resume program flow
Execute the code in single steps (single lines)
Run the task
Go to the next breakpoint
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Note: |
You can execute all DPL tasks in single steps except for event tasks, user-defined tasks and function blocks. |
You set breakpoints throughout a DPL program as required. However, these must be placed on lines of code, not on comments or blank lines. You can only set one breakpoint in a DPL task at any one time. Breakpoints cannot be used in sub-routines. QLD and LD/FBD diagrams are considered as a single line and as such are completely executed in a single step. In addition, breakpoints are cleared when target drives are switched off or reset.
Breakpoints are drawn in the left-hand margin of a DPL program. In the following example, a breakpoint is set on the line of code b% = a% * 100. The Background task will pause execution when it hits the breakpoint prior to executing the line of code.
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Note: |
Breakpoints are only visible while in on-line mode and are not stored with the DPL program. Breakpoints information is stored on the target drive and is uploaded by the DPL Editor when switching to on-line mode. Breakpoints are lost when the target drive is reset or powered off. |
The following shows how the DPL editor looks when a breakpoint has been hit, i.e. the task has been paused prior to the line on which the breapoint is set. Note that only the task containing the breakpoint has been paused - any other tasks will continue to run.
To set or clear a breakpoint
Place the cursor at the line of code where you want to set or clear a breakpoint and do one of the following:
Press F2.
From the Run menu, choose Toggle Breakpoint.
On the main toolbar press
Alternatively,
Double-click the grey column on the lefthand side of the DPL view on the line where you want to set a breakpoint.
To remove all breakpoints set in a program
From the Run menu, choose Remove all Breakpoints.
To go to the next breakpoint
From the Run menu, choose Go to Next Breakpoint.
See Also
Controlling Program Execution
Debugging Applications
Tasks
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