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xTaskCallApplicationTaskHook() - General Questions

Posted by westmorelandeng on March 28, 2015

Hello All,

I have some general questions regarding xTaskCallApplicationTaskHook() and the associated application task hook function -

*)When running in preemptive mode - does the hook run in the parent task time or does it run when the scheduler has switched out the parent task? *) Based on that answer - how does the hook get preempted? Or does it run until completion? *) Can the hook call any of the RTOS facilities or is that a no-no; i.e. vTaskDelay() might not be a good idea to call? *) If the hook is preempted; when the task restarts; does the task restart in the hook function?

Just some general questions and trying to get a feel for how it works. I wrote a real quick test function and works OK - just wondering what the recommended mode of operation is. I read the note about trace hook macros but was also wondering if it is more GP than that.

Thanks, John W.

xTaskCallApplicationTaskHook() - General Questions

Posted by rtel on March 28, 2015

The hook is just a function pointer - it has nothing special about it, and calling it is just like calling any function.


The hook runs in the context of whatever calls it. So if you call it form a task it will run in that task exactly where it is called. If you call it in the tick hook it will run in the tick hook exactly where you call it.

It will get preempted just like any regular function being called.


xTaskCallApplicationTaskHook() - General Questions

Posted by westmorelandeng on March 29, 2015

OK - thanks. I plan on making use of it.

Regards, John W.

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