X-Cube-Cellular low power

[NHuhs]

Hello all,

I am working with the LBAD0ZZ1SE module, also used on the B-L462E-CELL1.

I successfully adapted the "Nx_TCP_Echo_Client" Sample from X-Cube_cellular 7.1.0 to fit my needs but right now am stuck at the final step, which is the low power mode.

I configured ThreadX for low power:

And implemented the following functions:

/**
  * @brief  App_ThreadX_LowPower_Enter
  * @PAram  None
  * @retval None
  */
void App_ThreadX_LowPower_Enter(void)
{
  /* USER CODE BEGIN  App_ThreadX_LowPower_Enter */
	  ULONG currentValue = 0;
	  UINT ret;
	  tx_semaphore_info_get(&mainSemaphore, NULL, &currentValue, NULL, NULL, NULL);
	  ret = tx_semaphore_get(&mainSemaphore, TX_NO_WAIT);
	  if (ret == TX_SUCCESS)
	  {
	    HAL_GPIO_WritePin(SWITCH_GPIO_Port, SWITCH_Pin, GPIO_PIN_RESET);
	    printf("go to sleep\r\n");
	    /* Enter to the stop mode */
	    HAL_RTCEx_SetWakeUpTimer_IT(&hrtc, 60, RTC_WAKEUPCLOCK_CK_SPRE_16BITS);
	    HAL_PWREx_EnterSTOP2Mode(PWR_STOPENTRY_WFI);
	  }

  /* USER CODE END  App_ThreadX_LowPower_Enter */
}

and

/**
  * @brief  App_ThreadX_LowPower_Exit
  * @PAram  None
  * @retval None
  */
void App_ThreadX_LowPower_Exit(void)
{
  /* USER CODE BEGIN  App_ThreadX_LowPower_Exit */
	HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);
	SystemClock_Config();
	HAL_ResumeTick();
	HAL_GPIO_WritePin(SWITCH_GPIO_Port, SWITCH_Pin, GPIO_PIN_SET);
	if(tx_semaphore_put(&sleepSemaphore)== TX_SEMAPHORE_ERROR){
		while(1){
			 //HAL_GPIO_TogglePin(LED2_GPIO_Port, LED2_Pin);
			 HAL_Delay(1000);
		}
	}
  /* USER CODE END  App_ThreadX_LowPower_Exit */
}

I noticed in the docs for the package: 

"To support low power, the application must close the socket before entering low-power mode."

Which I respected at the end of my application.

	nxd_mqtt_client_delete(&mqtt_client);

	nx_dns_delete(DnsClientPtr);

	UINT ret = nx_ip_delete(p_IpInstance);

So there should be now open sockets.

But still the board does not seem to go to sleep.

I use the StLink-V3-PWR and am measuring this current draw from startup to "sleep".

Any help or ideas would be greatly aprreciated.