i am trying to wakeup stm32lo from sleep mode by interrupt push button connected to pA3

[NASOK.1]

 HAL_SuspendTick();

       /* Enter Sleep Mode,

        *

        */

   HAL_PWR_EnterSLEEPMode(PWR_MAINREGULATOR_ON, PWR_SLEEPENTRY_WFI);

       /* Resume Tick interrupt if disabled prior to SLEEP mode entry */

       HAL_ResumeTick();

I HAVE THE ABOVE CODE IN MY WHILE LOOP 

AND MY CALLBACK IS

void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
// if(GPIO_Pin == WKUP_INT_Pin)
// {
// HAL_GPIO_WritePin(GPIOB, USERLED_Pin, GPIO_PIN_SET);
// }
if(GPIO_Pin == STEP_INT_Pin)
{
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_SET);
} else {
__NOP();
}
}

I AM NOT AT ALL ENTERING THE SLEEP MODE THOUGH.

[RomainR.]

Hello @NASOK.1 

How do you find that the STM32L0 never goes into sleep?

Can you try the following example ? 
https://github.com/STMicroelectronics/STM32CubeL0/tree/master/Projects/NUCLEO-L053R8/Examples/PWR/PWR_SLEEP

BR
Romain,