STM32H750时钟频率和功耗和RTC功能测试

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• 📌相关篇《STM32H750片外QSPI启动配置简要》

✨在使用STM32CubeMX修改STM32H750时钟树参数时，如果使用软件自动求解，这是一个非常耗时的操作，有时候还不一定成功，还是推荐使用手动方式进行配置，这一点和STM32其他系列不同，像STM32F1系列，输入频率参数回车确认后，自动求解很快就自动配置完成了。可能和时钟配置参数的复杂度有关。

🔰STM32H750时钟频率和功耗粗略统计对比

• 🔖以下是在的单片机正常运行模式下的测试数据。（以个人自制的STM32H750核心板测试为例，数据不代表所有实际使用的STM32H750的运行状态能耗）

• 🌿外部晶振25MHz ， 480MHz主频，电流220mA，1.1w,芯片发热很大
• 🌿外部晶振 25MHz，400MHz，电流164mA，0.82w，芯片发热比较大
• 🌿 外部晶振25MHz， 250MHz，电流75mA，0.4w，芯片稍微发热

• 功耗主要源头和主频关系非常大，与是否使能的外设多少，测试没有明显的影响。
• 如果跑满单片机主频（480MHz）,长期运行，最好贴个散热片辅助散热，供电方面，至少500mA或以上输出能力的电源。

📙时钟频率配置参数

• 🔧25MHz外部晶振，配置480MHz
  

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Supply configuration update enable
  */
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  __HAL_RCC_SYSCFG_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  /** Configure LSE Drive Capability
  */
  HAL_PWR_EnableBkUpAccess();
  __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE|RCC_OSCILLATORTYPE_LSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.LSEState = RCC_LSE_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 5;
  RCC_OscInitStruct.PLL.PLLN = 192;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_2;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 0;
  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_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
  {
    Error_Handler();
  }
}

• 🔧25MHz外部晶振，配置400MHz
  

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Supply configuration update enable
  */
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  /** Configure LSE Drive Capability
  */
  HAL_PWR_EnableBkUpAccess();
  __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE|RCC_OSCILLATORTYPE_LSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.LSEState = RCC_LSE_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 5;
  RCC_OscInitStruct.PLL.PLLN = 160;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_2;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 0;
  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_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}

• 🔧8MHz外部晶振，配置480MHz
  

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Supply configuration update enable
  */
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  __HAL_RCC_SYSCFG_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  /** Configure LSE Drive Capability
  */
  HAL_PWR_EnableBkUpAccess();
  __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE|RCC_OSCILLATORTYPE_LSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.LSEState = RCC_LSE_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 32;
  RCC_OscInitStruct.PLL.PLLN = 240;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_2;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 7753;
  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_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
  {
    Error_Handler();
  }
}

• 🔧8MHz外部晶振，配置400MHz：RCC_OscInitStruct.PLL.PLLN = 240;
  

📘RTC时钟功能

• 🔖在使能RTC日历，配置参数时，最好选择RTC_FORMAT_BIN数据格式，在使用RTC_FORMAT_BCD数据格式，在读取数据就可以省去转换。
  

• 🌿如果使用RTC_FORMAT_BCD数据格式，转换为常规的十进制数参考代码：

RTC_HandleTypeDef hrtc;

void HAL_RTC_MspInit(RTC_HandleTypeDef *hrtc)
{
  /* Enable RTC clock */
  __HAL_RCC_RTC_ENABLE();
}

void RTC_BCDToDecimal(RTC_TimeTypeDef *sTime)
{
  sTime->Hours = ((sTime->Hours & 0xF0) >> 4) * 10 + (sTime->Hours & 0x0F);
  sTime->Minutes = ((sTime->Minutes & 0xF0) >> 4) * 10 + (sTime->Minutes & 0x0F);
  sTime->Seconds = ((sTime->Seconds & 0xF0) >> 4) * 10 + (sTime->Seconds & 0x0F);
}

int main(void)
{
  RTC_TimeTypeDef sTime;

  /* Initialize RTC */

  /* Get RTC time */
  HAL_RTC_GetTime(&hrtc, &sTime, RTC_FORMAT_BCD);

  /* Convert BCD to decimal */
  RTC_BCDToDecimal(&sTime);

  /* Use sTime.Hours, sTime.Minutes, sTime.Seconds as decimal values */

  while (1)
  {
    /* Application code */
  }
}

    

📗RTC功能测试代码

• ✨个人采用的是外部flash运行程序，下载算法和程序地址，和常规片内运行的程序有所不同，这一点需要注意。

int main(void)
{

  /* USER CODE BEGIN 1 */
	uint8_t Rtctmp=0;
	RTC_DateTypeDef GetData = {0}; //获取日期结构体
    RTC_TimeTypeDef GetTime = {0}; //获取时间结构体
    SCB->VTOR = 0x90000000; /*设置中断向量表偏移地址  */

  /* USER CODE END 1 */

  /* Enable the CPU Cache */

  /* Enable I-Cache---------------------------------------------------------*/
  SCB_EnableICache();

  /* Enable D-Cache---------------------------------------------------------*/
  SCB_EnableDCache();

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_RTC_Init();
  MX_USART1_UART_Init();
  /* USER CODE BEGIN 2 */

		/* 使能 PWR 时钟 */
//		__HAL_RCC_RTC_ENABLE();
		/* PWR_CR:DBF置1，使能RTC、RTC备份寄存器和备份SRAM的访问 */
//		HAL_PWR_EnableBkUpAccess();
		/* 等待 RTC APB 寄存器同步 */
//		HAL_RTC_WaitForSynchro(&hrtc);

  /* USER CODE END 2 */

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

    /* USER CODE BEGIN 3 */
        HAL_RTC_GetTime(&hrtc, &GetTime, RTC_FORMAT_BIN);//RTC_FORMAT_BCD
        HAL_RTC_GetDate(&hrtc, &GetData, RTC_FORMAT_BIN);  //RTC_FORMAT_BIN
			// 每秒打印一次
		if(Rtctmp != GetTime.Seconds)
		{
		
        printf("Data:%04d-%02d-%02d\r\n", 2000 + GetData.Year, GetData.Month, GetData.Date);
        printf("Time:%02d:%02d:%02d\r\n", GetTime.Hours, GetTime.Minutes, GetTime.Seconds);
        	
			HAL_GPIO_TogglePin(LED1_GPIO_Port, LED1_Pin);
			printf("STM32H750 SysClockFreq:%d \r\n", SystemCoreClock);
//			printf("STM32H750 SysClockFreq:%d \r\n", HAL_RCC_GetSysClockFreq());
//			(void)RTC->DR;
		}
		Rtctmp = GetTime.Seconds;
    }
  /* USER CODE END 3 */
}

📒RTC不走时的相关原因分析

• 🌿在调用读取时间数据 接口函数时，需要同时一起调用时间和日期对应的函数：

        HAL_RTC_GetTime(&hrtc, &GetTime, RTC_FORMAT_BIN);
        HAL_RTC_GetDate(&hrtc, &GetData, RTC_FORMAT_BIN);  

• 🌿在调用上面两个接口函数时，注意第一个形参，该形参是rtc被初始化过的句柄，被定义在：rtc.c中：

RTC_HandleTypeDef hrtc;

/* RTC init function */
void MX_RTC_Init(void)
{

  /* USER CODE BEGIN RTC_Init 0 */

  /* USER CODE END RTC_Init 0 */

  RTC_TimeTypeDef sTime = {0};
  RTC_DateTypeDef DateToUpdate = {0};

  /* USER CODE BEGIN RTC_Init 1 */

  /* USER CODE END RTC_Init 1 */

  /** Initialize RTC Only
  */
  hrtc.Instance = RTC;
  hrtc.Init.AsynchPrediv = RTC_AUTO_1_SECOND;
  hrtc.Init.OutPut = RTC_OUTPUTSOURCE_ALARM;
  if (HAL_RTC_Init(&hrtc) != HAL_OK)
  {
    Error_Handler();
  }

  /* USER CODE BEGIN Check_RTC_BKUP */

  /* USER CODE END Check_RTC_BKUP */

  /** Initialize RTC and set the Time and Date
  */
  sTime.Hours = 0x20;
  sTime.Minutes = 0x35;
  sTime.Seconds = 0x35;

  if (HAL_RTC_SetTime(&hrtc, &sTime, RTC_FORMAT_BCD) != HAL_OK)
  {
    Error_Handler();
  }
  DateToUpdate.WeekDay = RTC_WEEKDAY_MONDAY;
  DateToUpdate.Month = RTC_MONTH_APRIL;
  DateToUpdate.Date = 0x22;
  DateToUpdate.Year = 0x24;

  if (HAL_RTC_SetDate(&hrtc, &DateToUpdate, RTC_FORMAT_BCD) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN RTC_Init 2 */

  /* USER CODE END RTC_Init 2 */

}

• 🔖如果传递的是一个自己定义的一个rtc句柄（例如：RTC_HandleTypeDef Rtc_Handle;），而未进行初始化操作，直接作为形参传入该句柄，将会导致不走时。
• 🎉设置RTC时间的时候，用的那个变量作为句柄的，在调用读取时间信息的时候，也必须要使用相同的变量作为句柄来读取。
• 🔱如果必须要需使用自己定义的句柄，参考代码如下来做：

RTC_HandleTypeDef Rtc_Handle;

/**
  * @brief  设置时间和日期
  * @param  无
  * @retval 无
  */
void RTC_TimeAndDate_Set(void)
{
    RTC_DateTypeDef  RTC_DateStructure;
    RTC_TimeTypeDef  RTC_TimeStructure;
	// 初始化时间
	RTC_TimeStructure.TimeFormat = RTC_HOURFORMAT12_AM;
	RTC_TimeStructure.Hours = 8;        
	RTC_TimeStructure.Minutes = 12;      
	RTC_TimeStructure.Seconds = 26;      
    HAL_RTC_SetTime(&Rtc_Handle,&RTC_TimeStructure, RTC_FORMAT_BIN);
    // 初始化日期	
	RTC_DateStructure.WeekDay = RTC_WEEKDAY_TUESDAY;       
	RTC_DateStructure.Date = 23;         
	RTC_DateStructure.Month = RTC_MONTH_APRIL;         
	RTC_DateStructure.Year = 24;        
    HAL_RTC_SetDate(&Rtc_Handle,&RTC_DateStructure, RTC_FORMAT_BIN);
 
}

/**
  * @brief  显示时间和日期
  * @param  无
  * @retval 无
  */
void RTC_TimeAndDate_Show(void)
{
	uint8_t Rtctmp=0;
	
	RTC_TimeTypeDef RTC_TimeStructure;
	RTC_DateTypeDef RTC_DateStructure;
		
	while(1)
	{
		// 获取日历
		HAL_RTC_GetTime(&Rtc_Handle, &RTC_TimeStructure, RTC_FORMAT_BIN);
		HAL_RTC_GetDate(&Rtc_Handle, &RTC_DateStructure, RTC_FORMAT_BIN);
			
			// 每秒打印一次
		if(Rtctmp != RTC_TimeStructure.Seconds)
		{
							
			// 打印日期
			printf("The Date :  Y:20%0.2d - M:%0.2d - D:%0.2d - W:%0.2d\r\n", 
			RTC_DateStructure.Year,
			RTC_DateStructure.Month, 
			RTC_DateStructure.Date,
			RTC_DateStructure.WeekDay);
			
			// 打印时间
			printf("The Time :  %0.2d:%0.2d:%0.2d \r\n\r\n", 
			RTC_TimeStructure.Hours, 
			RTC_TimeStructure.Minutes, 
			RTC_TimeStructure.Seconds);
			
		}
		Rtctmp = RTC_TimeStructure.Seconds;
	}	
}

• 🌿另一个时钟不走时的可能就是，在使用外部低速时钟源作为时钟源时，外部32.756KHz晶振没有起振所致。