STM32U5 Stop mode with FreeRTOS

[JPortilha]

Hello,

I am using an STM32U585 with STOP mode and FreeRTOS in tickless idle mode. The datasheet says the current consumption should be around 4.5uA, however I am measuring 35uA on my custom board that only has the MCU and some decoupling capacitators. Can someone tell me if I need to add something in the code to lower consumption? Are the datasheet consumptions possible running an RTOS? I will leave my code and measurements in attach:

void PreSleepProcessing(uint32_t ulExpectedIdleTime)
{
/* place for user code */
	(void)ulExpectedIdleTime;
        __HAL_RCC_GPIOC_CLK_DISABLE();
        __HAL_RCC_GPIOH_CLK_DISABLE();
        __HAL_RCC_GPIOA_CLK_DISABLE();
        __HAL_RCC_GPIOB_CLK_DISABLE();
	HAL_ICACHE_Disable();
	HAL_SuspendTick();
	HAL_PWREx_EnterSTOP2Mode(PWR_STOPENTRY_WFI);
}

void PostSleepProcessing(uint32_t ulExpectedIdleTime)
{
/* place for user code */
	(void)ulExpectedIdleTime;
	SystemClock_Config();
	__HAL_RCC_GPIOC_CLK_ENABLE();
	__HAL_RCC_GPIOH_CLK_ENABLE();
	__HAL_RCC_GPIOA_CLK_ENABLE();
	__HAL_RCC_GPIOB_CLK_ENABLE();
	HAL_ICACHE_Enable();
	HAL_ResumeTick();
}

static void SystemPower_Config(void)
{

  /*
   * SRAM Power Down In Stop Mode Config
   */
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM1_PAGE1_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM1_PAGE2_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM1_PAGE3_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM2_PAGE1_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM2_PAGE2_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE1_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE2_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE3_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE4_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE5_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE6_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE7_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE8_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM4_FULL_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_ICACHE_FULL_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_DCACHE1_FULL_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_DMA2DRAM_FULL_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_PKA32RAM_FULL_STOP_RETENTION);
  HAL_PWREx_DisableRAMsContentStopRetention(PWR_PERIPHRAM_FULL_STOP_RETENTION);
/* USER CODE BEGIN PWR */
/* USER CODE END PWR */
}

void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Configure the main internal regulator output voltage
  */
  if (HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE4) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI|RCC_OSCILLATORTYPE_MSI;
  RCC_OscInitStruct.LSIState = RCC_LSI_ON;
  RCC_OscInitStruct.MSIState = RCC_MSI_ON;
  RCC_OscInitStruct.MSICalibrationValue = RCC_MSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_4;
  RCC_OscInitStruct.LSIDiv = RCC_LSI_DIV1;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2
                              |RCC_CLOCKTYPE_PCLK3;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }

  /** Enable the force of MSIK in stop mode
  */
  __HAL_RCC_MSIKSTOP_ENABLE();
}

[Saket_Om]

Hello @JPortilha 

To better isolate the source of the higher current consumption, could you please perform a first measurement in STOP2 mode without FreeRTOS enabled. 

[JPortilha]

Hello, I have used this code to measure STOP2 mode in bare metal.

  __HAL_RCC_PWR_CLK_ENABLE();

    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM1_PAGE1_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM1_PAGE2_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM1_PAGE3_STOP_RETENTION);
//    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM2_PAGE1_STOP_RETENTION);
//    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM2_PAGE2_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE1_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE2_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE3_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE4_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE5_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE6_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE7_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM3_PAGE8_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_SRAM4_FULL_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_ICACHE_FULL_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_DCACHE1_FULL_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_DMA2DRAM_FULL_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_PKA32RAM_FULL_STOP_RETENTION);
    HAL_PWREx_DisableRAMsContentStopRetention(PWR_PERIPHRAM_FULL_STOP_RETENTION);

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */

	HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_12);
	HAL_SuspendTick();
	if (HAL_RTCEx_SetWakeUpTimer_IT(&hrtc, 40000, RTC_WAKEUPCLOCK_RTCCLK_DIV16, 0) != HAL_OK)
	{
		Error_Handler();
	}

	HAL_PWREx_EnterSTOP2Mode(PWR_STOPENTRY_WFI);

	SystemClock_Config();
	HAL_ResumeTick();

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

I got around 12uA. This is way better than using FreeRTOS, however its still far from the 4.5uA advertised in the datasheet. Do you have any hints?

BR.

[Saket_Om]

Hello @JPortilha 

Please refer to the article below which cover the needed steps to use the FreeRTOS™ in tickless mode, specifically entering in STOP2 low-power mode with the STM32U5.

How to use STM32U5 with FreeRTOS™ in tickless mode - STMicroelectronics Community