[嵌入式]蓝桥杯STM32G431——RTC实时时钟

RTC基本定义

STM32的实时时钟(RTC)是一个独立的定时器。STM32的RTC模块拥有一组连续计数的计数器，在相应软件配置下，可提供时钟日历的功能。修改计数器的值可以重新设置系统当前的时间和日期。

RTC时钟框图

RTC配置一般步骤

1、使能PWR和BKP时钟
2、使能后备寄存器访问
3、配置RTC时钟源，使能RTC时钟:如果使用LSE，要打开LSE: RCC_LSEConfig(RCC_LSE_ON);
4、设置RTC预分频系数
5、设置时间
6、开启相关中断（如果需要)
7、编写中断服务函数
8、部分操作要等待写操作完成和同步。

RTC的初始化CubeMX基本配置

1、选择时钟源有效，日历有效

2、对时钟进行初始化配置

3、配置时钟树

RTC代码编写

rtc.c文件

#include "rtc.h"

RTC_HandleTypeDef hrtc;	//句柄结构体

void RTC_Init(void)	//RTC初始化函数
{

  /* 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;	//24小时计时方式
  hrtc.Init.AsynchPrediv = 125;
  hrtc.Init.SynchPrediv = 6000;	//完成分频最后输出1Hz
  hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
  hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
  hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
  hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
  hrtc.Init.OutPutPullUp = RTC_OUTPUT_PULLUP_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 = 0x12;	//时间初始值设置
  sTime.Minutes = 0x0;
  sTime.Seconds = 0x0;
  sTime.SubSeconds = 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_THURSDAY;	//日期设置
  sDate.Month = RTC_MONTH_FEBRUARY;
  sDate.Date = 0x3;	
  sDate.Year = 0x22;

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

  /* USER CODE END RTC_Init 2 */

}

void HAL_RTC_MspInit(RTC_HandleTypeDef* rtcHandle)
{

  if(rtcHandle->Instance==RTC)
  {
  /* USER CODE BEGIN RTC_MspInit 0 */

  /* USER CODE END RTC_MspInit 0 */
    /* RTC clock enable */
    __HAL_RCC_RTC_ENABLE();	//使能RTC时钟
  /* USER CODE BEGIN RTC_MspInit 1 */

  /* USER CODE END RTC_MspInit 1 */
  }
}

rtc.h文件

#ifndef __RTC_H
#define __RTC_H
#include "main.h"

extern RTC_HandleTypeDef hrtc;
void RTC_Init(void);
#endif

main.c文件

#include "main.h"
#include "stdio.h"
#include "string.h"
#include "lcd.h"
#include "rtc.h"

__IO uint32_t uwTick_LCD_State_Pointer;	
unsigned char Lcd_Disp_String[21];

//RTC结构体变量
RTC_TimeTypeDef T; //时间结构体
RTC_DateTypeDef D; //日期结构体

int main(void)
{
	//RTC初始化
	RTC_Init();
	while (1)
  	{
		LCD_Proc();
	}
}

void LCD_Proc(void)
{
	if(uwTick-uwTick_LCD_State_Pointer<100) return;
	uwTick_LCD_State_Pointer=uwTick;	
	
	//RTC时间和日期读取函数
	HAL_RTC_GetTime(&hrtc , &T , RTC_FORMAT_BIN);	
	HAL_RTC_GetDate(&hrtc , &D , RTC_FORMAT_BIN);	//时间和日期必须同时Get，否则时间无法正常计数
	
	memset(Lcd_Disp_String,0,sizeof(Lcd_Disp_String));
	sprintf((char*)Lcd_Disp_String, "Date: %02d-%02d-%02d " ,D.Year,D.Month,D.Date);	//显示日期22-02-03
	LCD_DisplayStringLine(Line0, Lcd_Disp_String);
	
	memset(Lcd_Disp_String,0,sizeof(Lcd_Disp_String));
	sprintf((char*)Lcd_Disp_String, "Time: %02d-%02d-%02d " ,T.Hours,T.Minutes,T.Seconds);	//显示时间从计数初值12-00-00开始计数
	LCD_DisplayStringLine(Line1, Lcd_Disp_String);
}

/**
  * @brief System Clock Configuration
`  * @retval None
  */
void SystemClock_Config(void)	//时钟初始化函数
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
	RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

  /** Configure the main internal regulator output voltage
  */
  HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);
  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV3;
  RCC_OscInitStruct.PLL.PLLN = 20;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
  RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
  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_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
	/** Initializes the peripherals clocks
  */
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_RTC|RCC_PERIPHCLK_USART1
                              |RCC_PERIPHCLK_ADC12;
  PeriphClkInit.Usart1ClockSelection = RCC_USART1CLKSOURCE_PCLK2;
  PeriphClkInit.Adc12ClockSelection = RCC_ADC12CLKSOURCE_SYSCLK;
  PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV32;

  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
}