【AT-START-F425测评】堆积木之实时时钟（ERTC）

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【AT-START-F425测评】堆积木之实时时钟（ERTC） [复制链接]

 

【实时时钟（ERTC）】

实时时钟用于配置日历时钟，修改 ERTC 中日历寄存器值可以修改系统的当前时间和日期。 ERTC 计数逻辑位于电池供电域，只要电池供电域有电，ERTC 便会一直运行，不受系统复位影响。在前面驱动LCD的前提下，参照官方提供的例子，把ertc驱动，并显示在LCD上：

1、在drivers文件夹下新建ertc.c跟ertc.h分别如下：

#ifndef __ERTC_H
#define __ERTC_H

#include "at32f425_clock.h"

void ertc_time_show(void);
void ertc_timestamp_show(void);
void ertc_config(void);
void ertc_timestamp_config(void);


#endif

ertc.c

#include "ertc.h"
#include "at32f425_board.h"
#include "rtthread.h"
/**
  * [url=home.php?mod=space&uid=159083]@brief[/url] configure the ertc peripheral by selecting the clock source.
  * @param  none
  * @retval none
  */
void ertc_config(void)
{
  /* enable the pwc clock */
  crm_periph_clock_enable(CRM_PWC_PERIPH_CLOCK, TRUE);

  /* allow access to ertc */
  pwc_battery_powered_domain_access(TRUE);

  /* reset ertc bpr domain */
  crm_battery_powered_domain_reset(TRUE);
  crm_battery_powered_domain_reset(FALSE);

  /* enable the lext osc */
  crm_clock_source_enable(CRM_CLOCK_SOURCE_LEXT, TRUE);

  /* wait till lext is ready */
  while(crm_flag_get(CRM_LEXT_STABLE_FLAG) == RESET)
  {
  }

  /* select the ertc clock source */
  crm_ertc_clock_select(CRM_ERTC_CLOCK_LEXT);

  /* enable the ertc clock */
  crm_ertc_clock_enable(TRUE);

  /* deinitializes the ertc registers */
  ertc_reset();
  
  /* wait for ertc apb registers update */
  ertc_wait_update();
  
  /* configure the ertc divider */
  /* ertc second(1hz) = ertc_clk / (div_a + 1) * (div_b + 1) */
  ertc_divider_set(127, 255);
  
  /* configure the ertc hour mode */
  ertc_hour_mode_set(ERTC_HOUR_MODE_24);
  
  /* set date: 2021-05-01 */
  ertc_date_set(22, 3, 29, 5);
  
  /* set time: 12:00:00 */
  ertc_time_set(21, 12, 0, ERTC_AM); 
}

/**
  * @brief  configure the ertc timestamp.
  * @param  none
  * @retval none
  */
void ertc_timestamp_config(void)
{
  exint_init_type exint_init_struct;
   
  /* configure nvic */
  nvic_irq_enable(ERTC_IRQn, 0, 0);

  /* configure exint */  
  exint_default_para_init(&exint_init_struct);
  exint_init_struct.line_enable   = TRUE;
  exint_init_struct.line_mode     = EXINT_LINE_INTERRUPUT;
  exint_init_struct.line_select   = EXINT_LINE_19;
  exint_init_struct.line_polarity = EXINT_TRIGGER_RISING_EDGE;
  exint_init(&exint_init_struct);
  
  /* enable the timestamp */
  ertc_timestamp_valid_edge_set(ERTC_TIMESTAMP_EDGE_FALLING);
  ertc_timestamp_enable(TRUE);
  
  /* enable the timestamp int */  
  ertc_interrupt_enable(ERTC_TS_INT, TRUE);  
}

/**
  * @brief  display the current date.
  * @param  none
  * @retval none
  */
void ertc_time_show(void)
{
  ertc_time_type time;
  
  /* get the current time */
  ertc_calendar_get(&time);
  
  /* display the curent time */  
  rt_kprintf("current time: "); 

  /* display date format : year-month-day */
  rt_kprintf("%02d-%02d-%02d ",time.year, time.month, time.day);      
  
  /* display time format : hour:min:sec */
  rt_kprintf("%02d:%02d:%02d\r\n\r\n",time.hour, time.min, time.sec);
}

/**
  * @brief  display the current timestamp.
  * @param  none
  * @retval none
  */
void ertc_timestamp_show(void)
{
  ertc_time_type time;
  
  /* get the current timestamp */
  ertc_timestamp_get(&time);

  /* display the current timestamp */
  printf("timestamp:    ");
  
  /* display date format : month-day */
  printf("   %02d-%02d ", time.month, time.day);   
  
  /* display time format : hour:min:sec */
  printf("%02d:%02d:%02d\r\n", time.hour, time.min, time.sec); 
}

main.c 新建任务：

static rt_thread_t tid_ertc = RT_NULL;

static void tid_ertc_entry(void *parameter)
{
	ertc_time_type time;
	char str[10];
  while(1)
	{
		/* get the current time */
		ertc_calendar_get(&time);
		//sprintf(str,"%d - %d - %d ",time.year, time.month, time.day);
		LCD_ShowIntNum(10,160,time.year+2000,4,BLACK, WHITE,32);
		LCD_ShowIntNum(80,160,time.month,2,BLACK, WHITE,32);
		LCD_ShowIntNum(120,160,time.day,2,BLACK, WHITE,32);
		
		LCD_ShowIntNum(10,200,time.hour,2,BLACK, WHITE,32);
		LCD_ShowChar(45,200,':',BLACK,WHITE,32,0);
		LCD_ShowIntNum(70,200,time.min,2,BLACK, WHITE,32);
		LCD_ShowChar(100,200,':',BLACK,WHITE,32,0);
		LCD_ShowIntNum(120,200,time.sec,2,BLACK, WHITE,32);
		rt_thread_mdelay(500);
		
	}
  
	
}

在mian主函数中启动任务：

  tid_ertc = rt_thread_create("ERTC",
                            tid_ertc_entry, RT_NULL,
                            THREAD_STACK_SIZE,
                            THREAD_PRIORITY, THREAD_TIMESLICE);
    /* 如果获得线程控制块，启动这个线程 */
    if (tid_ertc != RT_NULL)
        rt_thread_startup(tid_ertc);

编译通过后就可以显示实时时间了：

 【总结】RT_Thread就是方便搭积木，每写一个模块，加入任务函数就可以了。当然这个ERTC还是最基本的处理，比如还需要增加实时更改时间等。下一步，将继续以搭积木的方法加入对其他模块的测试。