jianpan2.c

这是一个单片机矩阵键盘的源程序.希望对初学单片机的朋友有用.

#include <reg52.h>
#define uchar unsigned char
#define uint unsigned int
sbit dula=P2^7;
sbit wela=P2^6;
uchar temp;
uint num;
uchar code table[]={
0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};
void delay(uchar);
void display(uchar);
void main()
{
	while(1)
	{
		P1=0xfe;
		temp=P1;
		temp=temp&0xf0;
	
		if(temp!=0xf0)
			{
				delay(50);
				if(temp!=0xf0)
					{
						switch(temp)
						{
							case 0xe0:num=0;
							break;
							case 0xd0:num=1;
							break;
							case 0xb0:num=2;
							break;
							case 0x70:num=3;
							break;
						}
					}
			}
		P1=0xfd;
		temp=P1;
		temp=temp&0xf0;
		if(temp!=0xf0)
			{
				delay(50);
				if(temp!=0xf0)
					{
						switch(temp)
						{
							case 0xe0:num=4;
							break;
							case 0xd0:num=5;
							break;
							case 0xb0:num=6;
							break;
							case 0x70:num=7;
							break;
						}
					}
			}
		P1=0xfb;
		temp=P1;
		temp=temp&0xf0;
		if(temp!=0xf0)
			{
				delay(50);
				if(temp!=0xf0)
					{
						switch(temp)
						{
							case 0xe0:num=8;
							break;
							case 0xd0:num=9;
							break;
							case 0xb0:num=10;
							break;
							case 0x70:num=11;
							break;
						}
					}
			}
		P1=0xf7;
		temp=P1;
		temp=temp&0xf0;
		if(temp!=0xf0)
			{
				delay(50);
				if(temp!=0xf0)
					{
						switch(temp)
						{
							case 0xe0:num=12;
							break;
							case 0xd0:num=13;
							break;
							case 0xb0:num=14;
							break;
							case 0x70:num=15;
							break;
						}
					}
			}
		display(num);
		}
}

void delay(uchar x)
{
	uchar a,b;
	for(a=x;a>0;a--)
	 for(b=200;b>0;b--);
}
void display(uchar num1)
{
	P0=table[num1];
	dula=1;
	dula=0;	
	P0=0xc0;
	wela=1;
	wela=0;
}