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Posted by avi asaf on February 18, 2009

hello all,

I am working on atmel at91sam7s256 base on IAR workbench 5.00.

the semaphore example which appears in FreeRtos Web site uses portYIELD_FROM_ISR macro,

its being called after xSemaphoreGiveFromISR and if xHigherPriorityTaskWoken was set to true.

first of all, I would like to understand, what is the Yield macro role ? is it uses in order to force a context switch after the interrupt routine is ended?

second, I didn't found portYIELD_FROM_ISR macro at all, so I was trying to use "taskYIELD" but the OS was crashed.

what am I doing wrong?

does any one can help me with that problem?



Posted by Dave on February 18, 2009
There is an example given under "interrupt service routines" on this page http://www.freertos.org/portsam7iar.html and most likely in the demo for your port as well.

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