title: Can FreeRTOS taskGetTickCount() not be polled?
body: <p>I think I either have a) a misunderstanding of the way FreeRTOS taskGetTickCount() function works or b) something not quite right with our port.</p>
  
  <p>I have some debugging where I'm showing the output of xTaskGetCount(). Any time I've done a vTaskDelayUntil(), it seems it's updated and is current. But if I do a spin-wait, waiting for it to increment, it never will. I <em>thought</em> the interrupt fired ever tick and incremented that value. But I'm only running one task at the moment, so perhaps it is smart enough to never check for a reschedule and the tickCount never gets updated? Anyone who can set me straight on how the FreeRTOS tick count works, I'd be much obliged.</p>
  
  <p>EDIT: A sample fragment:</p>
  
  <pre><code>void someTask(void * _)
  {
      portTickType now = xTaskGetTickCount();
      for( ; xTaskGetTickCount() - now &lt; 25; )
      {
          debug("%u", xTaskGetTickCount();
      }
  } 
  </code></pre>
  
  <p>This will spin forever, long past the 25 ms implied when tick = 1 ms. The output will just continually list the same value over and over and over. IF I add a vTaskDelay() to the bottom of the loop though, it will increment healthily, and drop out eventually.</p>