Simulate tasks running for x tick

Kernel
1

betlemme wrote on Wednesday, November 11, 2015:

Hi everybody,
dumb question. is this :

TickType_t xTime = xTaskGetTickCount ();
for ( TickType_t x = xTime; x <= xTime + TOT; x = xTaskGetTickCount () )
{
    //nothing
}

a proper way to keep a task in running state for TOT number of tick?

Enrico

2

rtel wrote on Wednesday, November 11, 2015:

It is not clear why you would want to do this - but if it is your intention to just have a task run continuously for a fixed number of ticks, then the code you suggest has a couple of problems:

  1. It assumes the task that is executing this code is the highest priority task. If it is not the highest priority task then it won’t necessarily run continuously without being preempted.

  2. I think the way you have formulated the tests will not take into account the tick count potentially overflowing. Better would be:

x = xTaskGetTickCount();
while( ( xTaskGetTickCount() - x ) < TOT )
{
}

  1. The code might be optimised away if you turn on compiler optimisation. Best to make the variables volatile.
3

betlemme wrote on Wednesday, November 11, 2015:

My goal is to create just a test application. Gold advices. thanks!