/* 6位數碼管演示程序:  顯示數碼從0---99循環,按 P3.2 按鍵,顯示從"0" 開始*/

#include <reg52.h>    

int count1s;	   	
unsigned int count1m;	
unsigned char  dis_bitcount=0;	
unsigned char  display_o[6];			
unsigned char  display_q[6];			

unsigned char code  SEG[11]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0xff};	
unsigned char dis_bitdriver=0;


void delay5ms()
{
	register int i;
	for (i=0;i<500;i++)
	;
}

main()
{
	unsigned char dcode;
	unsigned char p2code,p3code;
	count1m=0;	
	count1s=0;	
	while(1)
	{

		switch(dis_bitcount+1)	
	{
		case 1:dis_bitdriver=0x01;  break;/*display 1*/
		case 2:dis_bitdriver=0x02;  break;/*display 2*/
		case 3:dis_bitdriver=0x04;  break;/*display 3*/
		case 4:dis_bitdriver=0x08;  break;/*display 4*/
		case 5:dis_bitdriver=0x10;  break;/*display 5*/
		default:dis_bitdriver=0x20; break;/*display 6 */
		
	}
	p2code=P2;
	P2=p2code&0x40;
	dcode=SEG[display_q[dis_bitcount]];
	P0=SEG[display_q[dis_bitcount]]; 	
	P2=(p2code&0x40)|dis_bitdriver;
	if(dis_bitcount>=5) dis_bitcount=0;
	else dis_bitcount++;
	
	
	count1s++;
	if(count1s>=400)   
	{
		count1m++;
		count1s=0;
	}	
	p3code=P3&0x04;
	
	if(count1m>99) count1m=0;
	if(p3code==0) count1m=0;

	display_o[1]=count1m/10;
	display_o[0]=count1m-display_o[1]*10;
	display_q[1]=display_o[1];  
	display_q[0]=display_o[0]; 
	
	delay5ms();
	

	}
	
}