How is the IntHandler function passed to Timer_IF_IntSetup() is executed?

Hi Steve,

The interrupt handler invocation will depend on whether you are using TI_ROTS environment or not. In case of TI_RTOS the handler gets registered to TI_RTOS's interrupt framework. If no TI_ROTS, the handler address becomes part of the CortexM4 vector table directly.

Did I answered your question ?

Thanks and Regards,
Praveen

Hi Praveen

We are using FreeRTOS. I am using the handler to give a semaphore and need to know if I should call xSemaphoreGiveFromISR() or xSemaphoreGive() from within the handler.

Thanks,
Steve

Hi Steve,

You should use xSemaphoreGiveFromISR() from within the handler.

Thanks and Regards,
Praveen

Hi Praveen

If I call xSemaphoreGiveFromISR() from within the handler function then an assertion error is thrown by FreeRTOS.

So...

ISR calls handler()...

handler() calls xSemaphoreGiveFromISR()

xSemaphoreGiveFromISR() maps to xQueGenericSendFromISR()

xQueGenericSendFromISR() calls vPortValidateInterruptPriority()

vPortValidateInterruptPriority() throws the assertion error.

 

If xSemaphoreGiveFromISR() should definately be called from the interrupt handler function then do you have any thoughts as to why FreeRTOS is throwing an assertion error?

 

Best,

Steve

Hi Steve,

Apologies for delayed response.

FreeRTOS requires the interrupt handler invoking OS calls to have equal or lesser priority than configMAX_SYSCALL_INTERRUPT_PRIORITY.

By default all interrupts are set to highest priority, so you need change the timer interrupt priority by calling.

MAP_IntPrioritySet(GetPeripheralIntNum(ulBase, ulTimer), INT_PRIORITY_LVL_1);

Thanks and Regards,
Praveen

Hi Praveen

OK, I went to try this but GetPeripheralIntNum() is only defined if USE_TIRTOS is defined (in the timer_if.c). Is it OK to define GetPeripheralIntNum() for use with FreeRTOS?

Best,
Steve