Proper method to know function under interrupt

[GChen.6]

Hi,

Currently, I am looking for the method to detect this function is under ISR or not.

And I found that there has two snipset code,

<Example 1>

uint8_t isUnderInterrupt(void)

{

uint8_t status = THREAD_MODE;

if (SCB->ICSR & SCB_ICSR_VECTACTIVE_Msk)

  {

     status = ISR_MODE;

  }

return status;

}

After I studying programming manual, I think above function is proper method to detect

this function is under ISR or not (If there has wrong thought, please correct me, thank you).

And I check some web example, someone uses freeRTOS with M3 MCU and the Example 2 using different way to implement it, but even I check programming manual, I cannot understand it,

<Example 2>

if (0 == __get_CONTROL())

{

// Under ISR

}

else

{

// Under Normal

}

How can using read out CONTROL register bit (SPSEL, nPRIV) to know MCU is under ISR? (M3 with freeRTOS).

By the way, if Example 2 is good method to know, when I use M4 MCU with FPU, the CONTROL register bit is (FPCA, SPSEL, nPRIV) the Example 2 is still work?

Please to give me some suggestion to guide me which method is proper one when using in M4 with FPU under freeRTOS, thank you so much.

[Pavel A.]

If you use FreeRTOS, just call xPortIsInsideInterrupt.

"Some web example" is not a reliable source ;)

-- pa

[TDK]

The currently executing interrupt, if any, is stored in the VECTACTIVE bits in SCB->ICSR. This is a cortex register, look there for the details.

// return true if we're in an interrupt
inline bool InInterrupt() {
  return SCB->ICSR & SCB_ICSR_VECTACTIVE_Msk;
}

[GChen.6]

Hi,

Thank you all~~~

All your suggestion is very useful : )