09-定时器拓展应用

#include "reg52.h"

sbit S4 = P3^3;
sbit S5 = P3^2;

unsigned char fen = 0;
unsigned char miao = 0;
unsigned char t_005ms = 0;

void delay(unsigned char t)
{
	while(t--);
	
}
unsigned char code table[] = 
{
	0xc0,//0
	0xf9,//1
	0xa4,//2
	0xb0,//3
	0x99,//4
	0x92,//5
	0x82,//6
	0xf8,//7
	0x80,//8
	0x90,//9
	0x88,//A
	0x83,//B
	0xc6,//C
	0xa1,//D
	0x86,//E
	0x8e,//F
	0xbf,//-
	0x7f//.
};

void SelectHC573(unsigned char n)
{
	switch(n)
	{
		case 4:
		P2 = (P2&0x1f) | 0x80;
		break;
		case 5:
		P2 = (P2&0x1f) | 0xa0;
		break;
		case 6:
		P2 = (P2&0x1f) | 0xc0;
		break;
		case 7:
		P2 = (P2&0x1f) | 0xe0;
		break;
	}
	
}

void display(unsigned char val,unsigned char pos)
{
	SelectHC573(6);
	P0 = 0x01<<pos;
	SelectHC573(7);
	P0 = table[val];
}
void showtime()
{
	display(t_005ms%10,7);//个0.05ms
	delay(500);
	display(t_005ms/10,6);//十
	delay(500);
	display(16,5);
	delay(500);
	
	display(miao%10,4);//个秒
	delay(500);
	display(miao/10,3);//十
	delay(500);
	display(16,2);
	delay(500);
	
	display(fen%10,1);//个分
	delay(500);
	display(fen/10,0);//十
	delay(500);
	
}

//========定时器相关函数==============
void InitTimer0()
{
	TMOD = 0x01;
	TH0 = (65535 - 50000)/256;
	TL0 = (65535 - 50000)%256;
	
	ET0 = 1;
	EA = 1;
	TR0 = 1;
}

void Timer0() interrupt 1
{
	TH0 = (65535 - 50000)/256;
	TL0 = (65535 - 50000)%256;
	
	t_005ms++;
	if(t_005ms == 20)
	{
		miao++;
		t_005ms = 0;
		if(miao == 60)
		{
			fen++;
			miao = 0;
		}
		if(fen == 99)
		{
			fen = 0;
		}
	}
}

//==============按键扫描======================

void scan()
{
	if(S4 == 0) //启动暂停
	{
		delay(100);
		if(S4 == 0)
		{
			TR0 = ~TR0;
			while(S4 == 0)
			{
				showtime();
			}
				
		}
	}
	if(S5 == 0) //清零
	{
		delay(100);
		if(S5 == 0)
		{
			t_005ms = 0;
			fen = 0;
			miao = 0;
			while(S5 == 0)
			{
				showtime();
			}
		}
	}
}


void main()
{
	InitTimer0();
	while(1)
	{
		scan();
		showtime();
	}
}