timer.c

基于C语言编程的keil单片机时间显示定时器。相对于汇编语言

#include <at89x51.h>
unsigned char code disp_code[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71}; 

unsigned char count=0,second=0;

delay( unsigned char n)
{
	unsigned char i;
	for( ;n>0;n--)
	  for(i=0;i<125;i++);	
}

display()
{   unsigned char temp[2];
	
	temp[1]=second/10;  //高位
	temp[0]=second%10;  //低位
	P0=~disp_code[temp[1]];P2_4=0; delay(20);P2_4=1;
	P0=~disp_code[temp[0]];P2_5=0; delay(20);P2_5=1;
}

main()
{
	TMOD=0X10;//T1 定时, 模式1  
	TH1=0X3C;  //15536/256;
	TL1=0XB0;  //15536%256;
	TR1=1;  //启动定时器
    while(1)
	{
	display();
	if(TF1==1)
	 {  TF1=0;  //标志位清零
		TH1=0X3C; //重新赋初值
	    TL1=0XB0;  ////重新赋初值
		count++;//50ms计数加1
		if(count==10)
    	{
			second++;count=0;
		}

	 }
	
	}



}