keyboard.c

8*8键盘检测

#include<reg51.h>

typedef	unsigned char uchar;

sbit vclk = P1^0;
sbit qh = P1^1;
sbit sl = P1^2;

bit flag;

void delay(uchar count)	
{
	int i,j;
	for(j = count ; j ; j --)
		for(i = 125 ; i; i --);
}

void out_164(uchar set)
{
	SBUF = set;
	while(!TI);
	TI = 0;
}

uchar in_165()
{	
	uchar i,result;
	sl = 0;
	sl = 1;
	for(i = 8; i; i --)
	{
		result <<= 1;
		vclk = 0;
		if(qh == 1)
			result = result | 0x01;
		else
			result = result & 0xfe;
		vclk = 1;	
	}
	return result;
}

void init()
{	
	SCON = 0x00;
	TI = 0;
	out_164(0x00);
	vclk = 0;
}


void main()
{	

	init();
	do
	{	
		while(in_165() == 0xff);
		delay(10);
		if(in_165() != 0xff)
			flag = 0;
		else
			flag = 1;
	}while(flag);

	out_164(0x07);
	if(in_165() == 0xf7)
	{
		P2 = 0x02;
	}
	if(in_165() == 0xfb)
	{
		P2 = 0x11;
	}
	//后边还可以检查其他按钮；；
	
}