rtel wrote on Monday, February 16, 2015:
As we were just discussing in this thread: http://sourceforge.net/p/freertos/discussion/382005/thread/e717bb2f/#d81e if you are using tickles idle then you should >not< be doing any of this stuff in the idle hook - all you should be doing is defining the pre and post sleep macros if that is desirable to do something chip specific before and after the sleep respectively.
You cannot use another hook, or another task, because when the CPU is sleeping nothing is running (so the task you want to use to wake up is not running so can’t wake you up).
The tickless idle mode takes care of all this for you. It will wake up at the right time, or when an interrupt occurs.
Regards.