stm32h7 rtc掉电后复位（连接vbat）
stm32h7 rtc resets after power down (vbat is connected)
我正在使用 stm32h753 和 stm32cubemx，并尝试 运行 VBAT 上的 RTC 模块。为此，我将电池连接到 MCU。 RTC 连接到 LSE。接下来，我在代码中设置 RTC，然后断开 MCU 与电源的连接，然后重新连接。根据文档，这应该会自动将 RTC 电源从 VDD 切换到 VBAT。
我在启动的时候注释掉了MX_RTC_Init()，这样MCU重启的时候RTC就不会复位了。
下面是系统时钟配置、RTC初始化和复位后读取RTC寄存器的代码。
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {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);
/** Macro to configure the PLL clock source
*/
__HAL_RCC_PLL_PLLSOURCE_CONFIG(RCC_PLLSOURCE_HSE);
/** Initializes the CPU, AHB and APB busses clocks
*/
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 = 1;
RCC_OscInitStruct.PLL.PLLN = 84;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 4;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_3;
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 busses 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_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV4;
RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC|RCC_PERIPHCLK_USART3
|RCC_PERIPHCLK_SPI1|RCC_PERIPHCLK_SDMMC
|RCC_PERIPHCLK_ADC;
PeriphClkInitStruct.PLL2.PLL2M = 1;
PeriphClkInitStruct.PLL2.PLL2N = 25;
PeriphClkInitStruct.PLL2.PLL2P = 4;
PeriphClkInitStruct.PLL2.PLL2Q = 2;
PeriphClkInitStruct.PLL2.PLL2R = 2;
PeriphClkInitStruct.PLL2.PLL2RGE = RCC_PLL2VCIRANGE_3;
PeriphClkInitStruct.PLL2.PLL2VCOSEL = RCC_PLL2VCOMEDIUM;
PeriphClkInitStruct.PLL2.PLL2FRACN = 0;
PeriphClkInitStruct.SdmmcClockSelection = RCC_SDMMCCLKSOURCE_PLL;
PeriphClkInitStruct.Spi123ClockSelection = RCC_SPI123CLKSOURCE_PLL;
PeriphClkInitStruct.Usart234578ClockSelection = RCC_USART234578CLKSOURCE_D2PCLK1;
PeriphClkInitStruct.AdcClockSelection = RCC_ADCCLKSOURCE_PLL2;
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
}
这是 RTC 初始化代码
static void MX_RTC_Init(void)
{
/* USER CODE BEGIN RTC_Init 0 */
/* USER CODE END RTC_Init 0 */
RTC_TimeTypeDef sTime = {0};
RTC_DateTypeDef sDate = {0};
RTC_AlarmTypeDef sAlarm = {0};
/* USER CODE BEGIN RTC_Init 1 */
/* USER CODE END RTC_Init 1 */
/** Initialize RTC Only
*/
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127;
hrtc.Init.SynchPrediv = 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
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 = 0x0;
sTime.Minutes = 0x0;
sTime.Seconds = 0x0;
sTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
sTime.StoreOperation = RTC_STOREOPERATION_RESET;
if (HAL_RTC_SetTime(&hrtc, &sTime, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
sDate.WeekDay = RTC_WEEKDAY_MONDAY;
sDate.Month = RTC_MONTH_JANUARY;
sDate.Date = 0x1;
sDate.Year = 0x0;
if (HAL_RTC_SetDate(&hrtc, &sDate, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
/** Enable the Alarm A
*/
sAlarm.AlarmTime.Hours = 0x0;
sAlarm.AlarmTime.Minutes = 0x20;
sAlarm.AlarmTime.Seconds = 0x0;
sAlarm.AlarmTime.SubSeconds = 0x0;
sAlarm.AlarmTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
sAlarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_RESET;
sAlarm.AlarmMask = RTC_ALARMMASK_DATEWEEKDAY|RTC_ALARMMASK_HOURS;
sAlarm.AlarmSubSecondMask = RTC_ALARMSUBSECONDMASK_ALL;
sAlarm.AlarmDateWeekDaySel = RTC_ALARMDATEWEEKDAYSEL_DATE;
sAlarm.AlarmDateWeekDay = 0x1;
sAlarm.Alarm = RTC_ALARM_A;
if (HAL_RTC_SetAlarm_IT(&hrtc, &sAlarm, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
/** Enable the Alarm B
*/
sAlarm.AlarmTime.Minutes = 0x40;
sAlarm.Alarm = RTC_ALARM_B;
if (HAL_RTC_SetAlarm_IT(&hrtc, &sAlarm, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN RTC_Init 2 */
/* USER CODE END RTC_Init 2 */
}
这是我在启动后用来读取 rtc 寄存器值的代码：
HAL_RTC_GetTime(&hrtc, &sTime, RTC_FORMAT_BIN);
HAL_RTC_GetDate(&hrtc, &sDate, RTC_FORMAT_BIN);
float subSecondsFloat = ( 255 - sTime.SubSeconds );
subSecondsFloat = (subSecondsFloat /255);
subSecondsFloat = (subSecondsFloat * 1000);
year = (uint32_t) (sDate.Year);
month = (uint32_t) (sDate.Month);
day = (uint32_t) (sDate.Date);
hours = (uint32_t) (sTime.Hours);
minutes = (uint32_t) (sTime.Minutes);
seconds = (uint32_t) (sTime.Seconds);
subseconds = (uint32_t) (subSecondsFloat);
sprintf(usartSendBuffer,"\n%lu,%lu,%lu,%lu,%lu,%lu,%lu\n", year,month,day,hours, minutes,seconds,subseconds);
printf(usartSendBuffer);
当我将 MCU 与电源断开并重新连接到电源时，以上代码在电源复位后给出以下结果（RTC 寄存器值）：
159,10,9,32,51,51,4294967295
所以RTC在MCU复位的某处被复位了。考虑到我禁用了MX_RTC_Init()，我不知道RTC在哪里重置。
抱歉，如果这个问题很初级，我真的是这个领域的新手。
非常感谢任何帮助，谢谢。
此致，
沃里亚
确认一下：我也找不到使用VBat维护RTC时钟的例子；
只是提示：HAL RTC 时钟初始化将时钟和日历寄存器设置为零，这有点古怪。您必须从初始化代码中删除它，否则每次启动时都会将时钟设置为零：
/**
* @brief RTC Initialization Function
* @param None
* @retval None
*/
static void MX_RTC_Init(void)
{
/* USER CODE BEGIN RTC_Init 0 */
/* USER CODE END RTC_Init 0 */
#if TIME_DATE_SET_ON_BOOT == 1
RTC_TimeTypeDef sTime = {0};
RTC_DateTypeDef sDate = {0};
#endif
/* USER CODE BEGIN RTC_Init 1 */
/* USER CODE END RTC_Init 1 */
/** Initialize RTC Only
*/
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127;
hrtc.Init.SynchPrediv = 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
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
*/
#if TIME_DATE_SET_ON_BOOT == 1
sTime.Hours = 0x0;
sTime.Minutes = 0x0;
sTime.Seconds = 0x0;
sTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
sTime.StoreOperation = RTC_STOREOPERATION_RESET;
if (HAL_RTC_SetTime(&hrtc, &sTime, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
sDate.WeekDay = RTC_WEEKDAY_MONDAY;
sDate.Month = RTC_MONTH_JANUARY;
sDate.Date = 0x1;
sDate.Year = 0x0;
if (HAL_RTC_SetDate(&hrtc, &sDate, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
#endif
/* USER CODE BEGIN RTC_Init 2 */
/* USER CODE END RTC_Init 2 */
}
这是我的 STM32H7B3LIHxQ 处理器的启动代码：
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MPU Configuration--------------------------------------------------------*/
MPU_Config();
/* 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();
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
#if BACKEND_PERIPERHALS == 1
#if (TRAP_DIV_BY_ZERO_HARD_FAULT == 1 && DEBUG_NMI_FAULTS == 1)
SCB->CCR |= 0x10; // enable div-by-0 trap
#endif
/* Enable the Backup System and VBat parameters */
__HAL_RCC_BKPRAM_CLK_ENABLE();
HAL_PWREx_DisableBatteryCharging();
HAL_PWREx_EnableBkUpReg();
HAL_PWR_EnableBkUpAccess();
/* Enable Back up SRAM */
/* Enable write access to Backup domain */
PWR->CR1 |= PWR_CR1_DBP;
while((PWR->CR1 & PWR_CR1_DBP) == RESET)
{
}
#endif
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_CRC_Init();
MX_GPIO_Init();
MX_DMA2D_Init();
MX_LTDC_Init();
MX_I2C4_Init();
MX_OCTOSPI1_Init();
MX_TouchGFX_Init();
/* USER CODE BEGIN 2 */
#if BACKEND_PERIPERHALS == 1
MX_DMA_Init();
MX_TIM5_Init();
#if ADC2_ENABLED == 1
MX_ADC2_Init();
MX_TIM3_Init();
#endif
MX_CRC_Init();
MX_I2C1_Init();
#if OP_AMPS_ENABLED == 1
MX_OPAMP1_Init();
MX_OPAMP2_Init();
#endif
MX_RNG_Init();
MX_RTC_Init();
...
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
/** Supply configuration update enable
*/
HAL_PWREx_ConfigSupply(PWR_DIRECT_SMPS_SUPPLY);
/** Configure the main internal regulator output voltage
*/
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);
while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}
/** Configure LSE Drive Capability
*/
// __HAL_RCC_BKPRAM_CLK_ENABLE();
//
// HAL_PWREx_DisableBatteryCharging();
// HAL_PWREx_EnableBkUpReg();
// HAL_PWR_EnableBkUpAccess();
//
// __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);
/** Macro to configure the PLL clock source
*/
__HAL_RCC_PLL_PLLSOURCE_CONFIG(RCC_PLLSOURCE_HSE);
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48|RCC_OSCILLATORTYPE_HSI
|RCC_OSCILLATORTYPE_LSI|RCC_OSCILLATORTYPE_HSE
|RCC_OSCILLATORTYPE_LSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.LSEState = RCC_LSE_ON;
RCC_OscInitStruct.HSIState = RCC_HSI_DIV2;
RCC_OscInitStruct.HSICalibrationValue = 0;
RCC_OscInitStruct.LSIState = RCC_LSI_ON;
RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = 12;
RCC_OscInitStruct.PLL.PLLN = 280;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 2;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_1;
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_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV1;
RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3) != HAL_OK)
{
Error_Handler();
}
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC|RCC_PERIPHCLK_LTDC
|RCC_PERIPHCLK_RNG|RCC_PERIPHCLK_ADC
|RCC_PERIPHCLK_I2C1|RCC_PERIPHCLK_I2C4
|RCC_PERIPHCLK_OSPI;
PeriphClkInitStruct.PLL2.PLL2M = 24;
PeriphClkInitStruct.PLL2.PLL2N = 266;
PeriphClkInitStruct.PLL2.PLL2P = 2;
PeriphClkInitStruct.PLL2.PLL2Q = 2;
PeriphClkInitStruct.PLL2.PLL2R = 2;
PeriphClkInitStruct.PLL2.PLL2RGE = RCC_PLL2VCIRANGE_0;
PeriphClkInitStruct.PLL2.PLL2VCOSEL = RCC_PLL2VCOMEDIUM;
PeriphClkInitStruct.PLL2.PLL2FRACN = 0;
PeriphClkInitStruct.PLL3.PLL3M = 24;
PeriphClkInitStruct.PLL3.PLL3N = 201;
PeriphClkInitStruct.PLL3.PLL3P = 2;
PeriphClkInitStruct.PLL3.PLL3Q = 2;
PeriphClkInitStruct.PLL3.PLL3R = 41;
PeriphClkInitStruct.PLL3.PLL3RGE = RCC_PLL3VCIRANGE_0;
PeriphClkInitStruct.PLL3.PLL3VCOSEL = RCC_PLL3VCOMEDIUM;
PeriphClkInitStruct.PLL3.PLL3FRACN = 5462;
PeriphClkInitStruct.OspiClockSelection = RCC_OSPICLKSOURCE_PLL2;
PeriphClkInitStruct.RngClockSelection = RCC_RNGCLKSOURCE_HSI48;
PeriphClkInitStruct.I2c123ClockSelection = RCC_I2C123CLKSOURCE_D2PCLK1;
PeriphClkInitStruct.I2c4ClockSelection = RCC_I2C4CLKSOURCE_D3PCLK1;
PeriphClkInitStruct.AdcClockSelection = RCC_ADCCLKSOURCE_PLL2;
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSI, RCC_MCODIV_1);
}
这段代码工作正常。我可以移除主电源，时钟和备用 ram 继续滴答作响。
您需要检查备份状态。
参考以下代码。
这是使用STM32系列的日历示例。
/**
* @brief RTC Initialization Function
* @param None
* @retval None
*/
static void MX_RTC_Init(void)
{
/* USER CODE BEGIN RTC_Init 0 */
/* USER CODE END RTC_Init 0 */
RTC_TimeTypeDef sTime = {0};
RTC_DateTypeDef sDate = {0};
/* USER CODE BEGIN RTC_Init 1 */
/* USER CODE END RTC_Init 1 */
/** Initialize RTC Only
*/
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127; ///?// 127;
hrtc.Init.SynchPrediv = 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
if (HAL_RTC_Init(&hrtc) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN Check_RTC_BKUP */
/*##-1- Check if Data stored in BackUp register1: No Need to reconfigure RTC#*/
/* Read the Back Up Register 1 Data */
if (HAL_RTCEx_BKUPRead(&hrtc, RTC_BKP_DR0) != RTC_BKUP_DEFINE_CODE)
{
// Clear Backup registor : recover to current RTC information
// Set to Time/Date from current Time/Date
// Write a data in ad RTC Backup data register
HAL_RTCEx_BKUPWrite(&hrtc, RTC_BKP_DR0, RTC_BKUP_DEFINE_CODE);
} else
{
// Only read time and date
HAL_RTC_GetTime(&hrtc, Time, Format);
HAL_RTC_GetDate(&hrtc, Date, Format);
}
/* USER CODE END Check_RTC_BKUP */
/* USER CODE BEGIN RTC_Init 2 */
/* USER CODE END RTC_Init 2 */
}
刚看完你的代码我也遇到了类似的问题。
问题出在你的代码中。
sAlarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_RESET;
应该在后面
sAlarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_SET;
在 Ioc 文件中进入 RTC 并将存储操作设置更改为设置。
然后取消注释 MX_RTC_Init 函数。
我正在使用 stm32h753 和 stm32cubemx，并尝试 运行 VBAT 上的 RTC 模块。为此，我将电池连接到 MCU。 RTC 连接到 LSE。接下来，我在代码中设置 RTC，然后断开 MCU 与电源的连接，然后重新连接。根据文档，这应该会自动将 RTC 电源从 VDD 切换到 VBAT。
我在启动的时候注释掉了MX_RTC_Init()，这样MCU重启的时候RTC就不会复位了。
下面是系统时钟配置、RTC初始化和复位后读取RTC寄存器的代码。
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {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);
/** Macro to configure the PLL clock source
*/
__HAL_RCC_PLL_PLLSOURCE_CONFIG(RCC_PLLSOURCE_HSE);
/** Initializes the CPU, AHB and APB busses clocks
*/
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 = 1;
RCC_OscInitStruct.PLL.PLLN = 84;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 4;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_3;
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 busses 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_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV4;
RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC|RCC_PERIPHCLK_USART3
|RCC_PERIPHCLK_SPI1|RCC_PERIPHCLK_SDMMC
|RCC_PERIPHCLK_ADC;
PeriphClkInitStruct.PLL2.PLL2M = 1;
PeriphClkInitStruct.PLL2.PLL2N = 25;
PeriphClkInitStruct.PLL2.PLL2P = 4;
PeriphClkInitStruct.PLL2.PLL2Q = 2;
PeriphClkInitStruct.PLL2.PLL2R = 2;
PeriphClkInitStruct.PLL2.PLL2RGE = RCC_PLL2VCIRANGE_3;
PeriphClkInitStruct.PLL2.PLL2VCOSEL = RCC_PLL2VCOMEDIUM;
PeriphClkInitStruct.PLL2.PLL2FRACN = 0;
PeriphClkInitStruct.SdmmcClockSelection = RCC_SDMMCCLKSOURCE_PLL;
PeriphClkInitStruct.Spi123ClockSelection = RCC_SPI123CLKSOURCE_PLL;
PeriphClkInitStruct.Usart234578ClockSelection = RCC_USART234578CLKSOURCE_D2PCLK1;
PeriphClkInitStruct.AdcClockSelection = RCC_ADCCLKSOURCE_PLL2;
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
}
这是 RTC 初始化代码
static void MX_RTC_Init(void)
{
/* USER CODE BEGIN RTC_Init 0 */
/* USER CODE END RTC_Init 0 */
RTC_TimeTypeDef sTime = {0};
RTC_DateTypeDef sDate = {0};
RTC_AlarmTypeDef sAlarm = {0};
/* USER CODE BEGIN RTC_Init 1 */
/* USER CODE END RTC_Init 1 */
/** Initialize RTC Only
*/
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127;
hrtc.Init.SynchPrediv = 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
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 = 0x0;
sTime.Minutes = 0x0;
sTime.Seconds = 0x0;
sTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
sTime.StoreOperation = RTC_STOREOPERATION_RESET;
if (HAL_RTC_SetTime(&hrtc, &sTime, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
sDate.WeekDay = RTC_WEEKDAY_MONDAY;
sDate.Month = RTC_MONTH_JANUARY;
sDate.Date = 0x1;
sDate.Year = 0x0;
if (HAL_RTC_SetDate(&hrtc, &sDate, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
/** Enable the Alarm A
*/
sAlarm.AlarmTime.Hours = 0x0;
sAlarm.AlarmTime.Minutes = 0x20;
sAlarm.AlarmTime.Seconds = 0x0;
sAlarm.AlarmTime.SubSeconds = 0x0;
sAlarm.AlarmTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
sAlarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_RESET;
sAlarm.AlarmMask = RTC_ALARMMASK_DATEWEEKDAY|RTC_ALARMMASK_HOURS;
sAlarm.AlarmSubSecondMask = RTC_ALARMSUBSECONDMASK_ALL;
sAlarm.AlarmDateWeekDaySel = RTC_ALARMDATEWEEKDAYSEL_DATE;
sAlarm.AlarmDateWeekDay = 0x1;
sAlarm.Alarm = RTC_ALARM_A;
if (HAL_RTC_SetAlarm_IT(&hrtc, &sAlarm, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
/** Enable the Alarm B
*/
sAlarm.AlarmTime.Minutes = 0x40;
sAlarm.Alarm = RTC_ALARM_B;
if (HAL_RTC_SetAlarm_IT(&hrtc, &sAlarm, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN RTC_Init 2 */
/* USER CODE END RTC_Init 2 */
}
这是我在启动后用来读取 rtc 寄存器值的代码：
HAL_RTC_GetTime(&hrtc, &sTime, RTC_FORMAT_BIN);
HAL_RTC_GetDate(&hrtc, &sDate, RTC_FORMAT_BIN);
float subSecondsFloat = ( 255 - sTime.SubSeconds );
subSecondsFloat = (subSecondsFloat /255);
subSecondsFloat = (subSecondsFloat * 1000);
year = (uint32_t) (sDate.Year);
month = (uint32_t) (sDate.Month);
day = (uint32_t) (sDate.Date);
hours = (uint32_t) (sTime.Hours);
minutes = (uint32_t) (sTime.Minutes);
seconds = (uint32_t) (sTime.Seconds);
subseconds = (uint32_t) (subSecondsFloat);
sprintf(usartSendBuffer,"\n%lu,%lu,%lu,%lu,%lu,%lu,%lu\n", year,month,day,hours, minutes,seconds,subseconds);
printf(usartSendBuffer);
当我将 MCU 与电源断开并重新连接到电源时，以上代码在电源复位后给出以下结果（RTC 寄存器值）：
159,10,9,32,51,51,4294967295
所以RTC在MCU复位的某处被复位了。考虑到我禁用了MX_RTC_Init()，我不知道RTC在哪里重置。
抱歉，如果这个问题很初级，我真的是这个领域的新手。
非常感谢任何帮助，谢谢。
此致，
沃里亚
确认一下：我也找不到使用VBat维护RTC时钟的例子；
只是提示：HAL RTC 时钟初始化将时钟和日历寄存器设置为零，这有点古怪。您必须从初始化代码中删除它，否则每次启动时都会将时钟设置为零：
/**
* @brief RTC Initialization Function
* @param None
* @retval None
*/
static void MX_RTC_Init(void)
{
/* USER CODE BEGIN RTC_Init 0 */
/* USER CODE END RTC_Init 0 */
#if TIME_DATE_SET_ON_BOOT == 1
RTC_TimeTypeDef sTime = {0};
RTC_DateTypeDef sDate = {0};
#endif
/* USER CODE BEGIN RTC_Init 1 */
/* USER CODE END RTC_Init 1 */
/** Initialize RTC Only
*/
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127;
hrtc.Init.SynchPrediv = 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
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
*/
#if TIME_DATE_SET_ON_BOOT == 1
sTime.Hours = 0x0;
sTime.Minutes = 0x0;
sTime.Seconds = 0x0;
sTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
sTime.StoreOperation = RTC_STOREOPERATION_RESET;
if (HAL_RTC_SetTime(&hrtc, &sTime, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
sDate.WeekDay = RTC_WEEKDAY_MONDAY;
sDate.Month = RTC_MONTH_JANUARY;
sDate.Date = 0x1;
sDate.Year = 0x0;
if (HAL_RTC_SetDate(&hrtc, &sDate, RTC_FORMAT_BCD) != HAL_OK)
{
Error_Handler();
}
#endif
/* USER CODE BEGIN RTC_Init 2 */
/* USER CODE END RTC_Init 2 */
}
这是我的 STM32H7B3LIHxQ 处理器的启动代码：
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MPU Configuration--------------------------------------------------------*/
MPU_Config();
/* 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();
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
#if BACKEND_PERIPERHALS == 1
#if (TRAP_DIV_BY_ZERO_HARD_FAULT == 1 && DEBUG_NMI_FAULTS == 1)
SCB->CCR |= 0x10; // enable div-by-0 trap
#endif
/* Enable the Backup System and VBat parameters */
__HAL_RCC_BKPRAM_CLK_ENABLE();
HAL_PWREx_DisableBatteryCharging();
HAL_PWREx_EnableBkUpReg();
HAL_PWR_EnableBkUpAccess();
/* Enable Back up SRAM */
/* Enable write access to Backup domain */
PWR->CR1 |= PWR_CR1_DBP;
while((PWR->CR1 & PWR_CR1_DBP) == RESET)
{
}
#endif
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_CRC_Init();
MX_GPIO_Init();
MX_DMA2D_Init();
MX_LTDC_Init();
MX_I2C4_Init();
MX_OCTOSPI1_Init();
MX_TouchGFX_Init();
/* USER CODE BEGIN 2 */
#if BACKEND_PERIPERHALS == 1
MX_DMA_Init();
MX_TIM5_Init();
#if ADC2_ENABLED == 1
MX_ADC2_Init();
MX_TIM3_Init();
#endif
MX_CRC_Init();
MX_I2C1_Init();
#if OP_AMPS_ENABLED == 1
MX_OPAMP1_Init();
MX_OPAMP2_Init();
#endif
MX_RNG_Init();
MX_RTC_Init();
...
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
/** Supply configuration update enable
*/
HAL_PWREx_ConfigSupply(PWR_DIRECT_SMPS_SUPPLY);
/** Configure the main internal regulator output voltage
*/
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);
while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}
/** Configure LSE Drive Capability
*/
// __HAL_RCC_BKPRAM_CLK_ENABLE();
//
// HAL_PWREx_DisableBatteryCharging();
// HAL_PWREx_EnableBkUpReg();
// HAL_PWR_EnableBkUpAccess();
//
// __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);
/** Macro to configure the PLL clock source
*/
__HAL_RCC_PLL_PLLSOURCE_CONFIG(RCC_PLLSOURCE_HSE);
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48|RCC_OSCILLATORTYPE_HSI
|RCC_OSCILLATORTYPE_LSI|RCC_OSCILLATORTYPE_HSE
|RCC_OSCILLATORTYPE_LSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.LSEState = RCC_LSE_ON;
RCC_OscInitStruct.HSIState = RCC_HSI_DIV2;
RCC_OscInitStruct.HSICalibrationValue = 0;
RCC_OscInitStruct.LSIState = RCC_LSI_ON;
RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = 12;
RCC_OscInitStruct.PLL.PLLN = 280;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 2;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_1;
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_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV1;
RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3) != HAL_OK)
{
Error_Handler();
}
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC|RCC_PERIPHCLK_LTDC
|RCC_PERIPHCLK_RNG|RCC_PERIPHCLK_ADC
|RCC_PERIPHCLK_I2C1|RCC_PERIPHCLK_I2C4
|RCC_PERIPHCLK_OSPI;
PeriphClkInitStruct.PLL2.PLL2M = 24;
PeriphClkInitStruct.PLL2.PLL2N = 266;
PeriphClkInitStruct.PLL2.PLL2P = 2;
PeriphClkInitStruct.PLL2.PLL2Q = 2;
PeriphClkInitStruct.PLL2.PLL2R = 2;
PeriphClkInitStruct.PLL2.PLL2RGE = RCC_PLL2VCIRANGE_0;
PeriphClkInitStruct.PLL2.PLL2VCOSEL = RCC_PLL2VCOMEDIUM;
PeriphClkInitStruct.PLL2.PLL2FRACN = 0;
PeriphClkInitStruct.PLL3.PLL3M = 24;
PeriphClkInitStruct.PLL3.PLL3N = 201;
PeriphClkInitStruct.PLL3.PLL3P = 2;
PeriphClkInitStruct.PLL3.PLL3Q = 2;
PeriphClkInitStruct.PLL3.PLL3R = 41;
PeriphClkInitStruct.PLL3.PLL3RGE = RCC_PLL3VCIRANGE_0;
PeriphClkInitStruct.PLL3.PLL3VCOSEL = RCC_PLL3VCOMEDIUM;
PeriphClkInitStruct.PLL3.PLL3FRACN = 5462;
PeriphClkInitStruct.OspiClockSelection = RCC_OSPICLKSOURCE_PLL2;
PeriphClkInitStruct.RngClockSelection = RCC_RNGCLKSOURCE_HSI48;
PeriphClkInitStruct.I2c123ClockSelection = RCC_I2C123CLKSOURCE_D2PCLK1;
PeriphClkInitStruct.I2c4ClockSelection = RCC_I2C4CLKSOURCE_D3PCLK1;
PeriphClkInitStruct.AdcClockSelection = RCC_ADCCLKSOURCE_PLL2;
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSI, RCC_MCODIV_1);
}
这段代码工作正常。我可以移除主电源，时钟和备用 ram 继续滴答作响。
您需要检查备份状态。
参考以下代码。 这是使用STM32系列的日历示例。
/**
* @brief RTC Initialization Function
* @param None
* @retval None
*/
static void MX_RTC_Init(void)
{
/* USER CODE BEGIN RTC_Init 0 */
/* USER CODE END RTC_Init 0 */
RTC_TimeTypeDef sTime = {0};
RTC_DateTypeDef sDate = {0};
/* USER CODE BEGIN RTC_Init 1 */
/* USER CODE END RTC_Init 1 */
/** Initialize RTC Only
*/
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127; ///?// 127;
hrtc.Init.SynchPrediv = 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
if (HAL_RTC_Init(&hrtc) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN Check_RTC_BKUP */
/*##-1- Check if Data stored in BackUp register1: No Need to reconfigure RTC#*/
/* Read the Back Up Register 1 Data */
if (HAL_RTCEx_BKUPRead(&hrtc, RTC_BKP_DR0) != RTC_BKUP_DEFINE_CODE)
{
// Clear Backup registor : recover to current RTC information
// Set to Time/Date from current Time/Date
// Write a data in ad RTC Backup data register
HAL_RTCEx_BKUPWrite(&hrtc, RTC_BKP_DR0, RTC_BKUP_DEFINE_CODE);
} else
{
// Only read time and date
HAL_RTC_GetTime(&hrtc, Time, Format);
HAL_RTC_GetDate(&hrtc, Date, Format);
}
/* USER CODE END Check_RTC_BKUP */
/* USER CODE BEGIN RTC_Init 2 */
/* USER CODE END RTC_Init 2 */
}
刚看完你的代码我也遇到了类似的问题。 问题出在你的代码中。
sAlarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_RESET;
应该在后面
sAlarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_SET;
在 Ioc 文件中进入 RTC 并将存储操作设置更改为设置。 然后取消注释 MX_RTC_Init 函数。