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long vTaskDelay() problem

Posted by pierreculot on November 23, 2016


I'm working with STM32, and a tick each 1 ms.

I get problem with vTaskDelay more than 10000. I test like this:

before = xTaskGetTickCount(); vTaskDelay(10000); after = xTaskGetTickCount();

In this case we get exaclty after = before + 10000 and my stopwatch indicates 10 seconds. So far so good.

With a vTaskDelay more than 20000, my stopwatch indicates less than 20 seconds and after != (before + 10000).

I have the same problem with vTaskDelayUntil.

configUSE16BIT_TICKS is set at 0.

I don't understand why? I was thinking that we can program a delay of 4294967295 ms.


long vTaskDelay() problem

Posted by rtel on November 23, 2016

What else is your system doing? Try creating a test project that only creates one task that has no code in it other than the test code you posted above, and does not use any third party drivers. Do you then still see the same issue?

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