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cembeddedfreertosrtosnrf52

FreeRTOS can't set isr routine as critical region

I am running FreeRTOS on a nrf52840
I have 2 interrupts running and my RTOS crashes if I enter in an interrupt while in another one
To avoid such case I added the critical region functions, I also added debug pins to see time spent in the two irqs

void my_irq (void)
{
    BaseType_t xHigherPriorityTaskWoken;
    UBaseType_t uxSavedInterruptStatus;
    uxSavedInterruptStatus = taskENTER_CRITICAL_FROM_ISR();
    d_set_pin();
    xHigherPriorityTaskWoken = pdFALSE;
    
    /* some code */
    
    vTaskNotifyGiveFromISR(acq->task.handler, &xHigherPriorityTaskWoken);
    
    portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
    
    d_clear_pin();
    taskEXIT_CRITICAL_FROM_ISR(uxSavedInterruptStatus);
}

It did not work so I tried disabling interrupts :

void my_irq (void)
{
    BaseType_t xHigherPriorityTaskWoken;
    taskDISABLE_INTERRUPTS();
    d_set_pin();
    xHigherPriorityTaskWoken = pdFALSE;
    
    /* some code */
    
    vTaskNotifyGiveFromISR(acq->task.handler, &xHigherPriorityTaskWoken);

    portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
    
    d_clear_pin();
    taskENABLE_INTERRUPTS();
}

But still I get this and it crashes :

logic capture of irq

Do you have any ideas why my MCU leaves the interrupt routine ?

Solution

  • Your MCU is built around ARM Cortex-M4F kernel. I'm sorry, you didn't mention this in your question, did you set interrupt priorities correctly, according to this: https://www.freertos.org/RTOS-Cortex-M3-M4.html ?

    Also I've found that you can't call FreeRTOS API functions from within critical section in the ISR. See this: https://www.freertos.org/taskENTER_CRITICAL_FROM_ISR_taskEXIT_CRITICAL_FROM_ISR.html

    I'm sorry again if you've already checked these moments.