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Task creation

Posted by tns1 on October 1, 2008

Some clarification needed on task creation, terminology.

In the demos, the places where tasks are created often have the comment 'task started', even when the call to TaskStartScheduler has not happened yet.

I assume that no task is capable of starting until the call to TaskStartScheduler.
I also assume that if the scheduler is already running, then TaskCreate is all that is needed to create and start a new task.

Is there a way to create a task which is suspended by default, and which requires a call to resume before running?

The OS I am replacing has this capability. It looks like this could possibly be done if I could suspend a task before TaskStartScheduler is ever called. Can I? Another way is if there were a reserved 'no start' priority, or with a flag passed in pvParameters.


RE: Task creation

Posted by Dave on October 1, 2008
Your assumptions are right. Tasks will not run until the scheduler is started. If the scheduler is already running when the task is created it can run straight away, depending on its priority.

There is no way to create a task in the suspended state, but you can have the task put itself into the suspended state as soon as it starts running. You can even have it as a high priority task to ensure it runs first, then suspend itself, and put its priority to its proper level when it is un suspended. I don't think you can suspend it before the scheduler has started.

RE: Task creation

Posted by tns1 on October 1, 2008
I see. If I put that SuspendTask call before the task's infinite loop, then it should behave the same as the old OS.

Thanks


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