main.c

从零开始学51单片机源代码

//main.c
#include <reg51.h>	//包含头文件    
#include "fun.h"  

void  INT0_interrupt() interrupt 0
{
 	running = ~running;	  //切换暂停/计时
	if (running)
	{//切换为运行 
		TR0 = 1;
	}
	else
	{ //切换为暂停 
		TR0 = 0;
	} 
}

void Timer0_interrupt() interrupt 1
{
	TH0 = T0_50ms >> 8;	   //重装初值 
	TL0 = T0_50ms;

	if ((++ count_in_T0) == 20)//count_in_T0自加到20，计时1s
	{
		count_in_T0 = 0;
		if ( (++ display_num) ==60)
		{//display_num自加1后判断是否等于60
		 	display_num = 0;
		}
	}
}

main()
{
	unsigned char shi, ge;	//定义十位、个位要输出的数据 

	init_port();
	init_int();	
	init_timer();
	
	display_num = 0;
	count_in_T0 = 0;
	running = 0;
	//把两个数码管都关闭 
	en2 = 1;
	en1 = 1;
	EA = 1;//开总中断 
	TR0 = 1;//启动T0

	while(1)
	{
		shi =  display_num / 10;
		ge = display_num % 10;
		display(shi,ge);
		//检测清零按键 
		if ( clear == 0)
		{
			ms_delay(10);
			if ( clear == 0 )
			{//确认按下清零按钮 
				if ( !running )//如果处于暂停状态 
					display_num = 0;
			}
		}
	}
}