基于Proteus的51系列单片机设计与仿真

				/****************************************************************************
							59秒计时器的设计
				******************************************************************************/
				#include"reg51.h"
				#define uchar unsigned char
				#define uint unsigned int
				sbit p21=P2^1;
				sbit p20=P2^0;
				uint t=0;
				uchar count;
				uchar counth,countl;
				const uchar tab[]={  0XC0,0XF9,0XA4,0XB0,0X99,/*0~9*/
				                     0X92,0X82,0XF8,0X80,0X90};
				void delay(void)     //延时
				{         uint i;
				          for(i=0;i				}
				void time0_server_(void) interrupt 1
				{   
					TH0=0x3C;      //定时时间为 50ms  12MHZ的晶振
				    TL0=0xB0;
					t++;
				}
				void Init_t0(void)    //定时器初始化
				{
				      TMOD=0X01;     //选择方式1
					  TH0=0x3C;
				      TL0=0xB0;
				 	  EA=1;
				      ET0=1;
				      TR0=1;  
				}
				void display(void)
				 {counth=count/10;
				  countl=count%10;
				  P1=tab[counth];   //十位显示
				  p21=1;
				  delay();
				  p21=0;
				  P1=tab[countl];   //十位显示
				  p20=1;
				  delay();
				  p20=0;
				 }
				void main(void)
				{   count=0;
				      while(1)                     //0到99的显示
					     {if(t==20)
						   {if(count==59)
					         count=0;}
							t=0;
							count++;
							display();
				   }   
				}