# 工程创建参考：https://shequ.stmicroelectronics ... p;extra=#pid2657071

# CubeMX配置工程


# 修改代码
    static void MX_LPTIM3_Init(void)
    {

    /* USER CODE BEGIN LPTIM3_Init 0 */

    /* USER CODE END LPTIM3_Init 0 */

    /* USER CODE BEGIN LPTIM3_Init 1 */

    /* USER CODE END LPTIM3_Init 1 */
    hlptim3.Instance = LPTIM3;
    hlptim3.Init.Clock.Source = LPTIM_CLOCKSOURCE_APBCLOCK_LPOSC;
    hlptim3.Init.Clock.Prescaler = LPTIM_PRESCALER_DIV128;
    hlptim3.Init.Trigger.Source = LPTIM_TRIGSOURCE_SOFTWARE;
    hlptim3.Init.Period = 65535;
    hlptim3.Init.UpdateMode = LPTIM_UPDATE_IMMEDIATE;
    hlptim3.Init.CounterSource = LPTIM_COUNTERSOURCE_INTERNAL;
    hlptim3.Init.Input1Source = LPTIM_INPUT1SOURCE_GPIO;
    hlptim3.Init.Input2Source = LPTIM_INPUT2SOURCE_GPIO;
    hlptim3.Init.RepetitionCounter = 0;
    if (HAL_LPTIM_Init(&hlptim3) != HAL_OK)
    {
        Error_Handler();
    }
    /* USER CODE BEGIN LPTIM3_Init 2 */
    HAL_LPTIM_Counter_Start_IT(&hlptim3);//添加启动低功耗定时器
    /* USER CODE END LPTIM3_Init 2 */

    }


    while (1)
    {

        /* -- Sample board code for User push-button in interrupt mode ---- */
        if (BspButtonState == BUTTON_PRESSED)
        {
        /* Update button state */
        BspButtonState = BUTTON_RELEASED;
        /* -- Sample board code to toggle leds ---- */
        BSP_LED_Toggle(LED_GREEN);
        /* ..... Perform your action ..... */
        }
        HAL_SuspendTick();//添加进入休眠，以及串口打印命令
        printf("\r\n Enter sleep mode! \r\n");
        BSP_LED_Off(LED_GREEN);
        HAL_PWR_EnterSLEEPMode(PWR_MAINREGULATOR_ON, PWR_SLEEPENTRY_WFI);

        /* USER CODE END WHILE */

        /* USER CODE BEGIN 3 */
    }

    /* USER CODE BEGIN 0 */
    void HAL_LPTIM_UpdateEventCallback(LPTIM_HandleTypeDef *hlptim)
    {//添加回调函数、唤西醒并打印提示
        HAL_ResumeTick();
        BSP_LED_On(LED_GREEN);
        printf("\r\n Exit sleep mode ! \r\n");
    }
    /* USER CODE END 0 */


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