/*用矩阵键盘输入数字在数码管显示*/
矩阵键盘代码的编写有点像VHDL 编码器的书写，很多那些数字都是根据唯一的扫描位置来定，也就是说这些数字可以任意设置，主要就是巧妙在“
0xf0&0xfe” 通过这样确定出一定的位置，然后“编码”为你想要位置所代表的数字。矩阵键盘其实代码都很固定，很多东西其实也可以算是一沉不变的，
作为初学者继续加油吧！
#include<reg52.h>
#define uint unsigned int#define uchar unsigned charsbit dula=P2^6;sbit wela=P2^7;sbit key1=P3^4;uchar code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71,0};uchar num,temp,num1;void delay(uint z){ uint x,y; for(x=z;x>0;x--) for(y=110;y>0;y--);}uchar keyscan();void display(uchar aa);void main(){ num=17; dula=1; P0=0; dula=0; wela=1; P0=0x00; wela=0; while(1) { display(keyscan()); }}void display(uchar aa){ dula=1; P0=table[aa-1]; dula=0; }uchar keyscan(){ P3=0xfe; temp=P3; temp=temp&0xf0; //0xf0&0xfe while(temp!=0xf0) { delay(5); temp=P3; temp=temp&0xf0; //延时消抖 while(temp!=0xf0) { temp=P3; switch(temp) { case 0xee:num=1; break; case 0xde:num=2; break; case 0xbe:num=3; break; case 0x7e:num=4; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } } } P3=0xfd; temp=P3; temp=temp&0xf0; while(temp!=0xf0) { delay(5); temp=P3; temp=temp&0xf0; while(temp!=0xf0) { temp=P3; switch(temp) { case 0xed:num=5; break; case 0xdd:num=6; break; case 0xbd:num=7; break; case 0x7d:num=8; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } } } P3=0xfb; temp=P3; temp=temp&0xf0; while(temp!=0xf0) { delay(5); temp=P3; temp=temp&0xf0; while(temp!=0xf0) { temp=P3; switch(temp) { case 0xeb:num=9; break; case 0xdb:num=10; break; case 0xbb:num=11; break; case 0x7b:num=12; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } } } P3=0xf7; temp=P3; temp=temp&0xf0; while(temp!=0xf0) { delay(5); temp=P3; temp=temp&0xf0; while(temp!=0xf0) { temp=P3; switch(temp) { case 0xe7:num=13; break; case 0xd7:num=14; break; case 0xb7:num=15; break; case 0x77:num=16; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } } }return num;}
