单片机键盘扫描

1、本文给出单片机键盘扫描的两种程序。供大家学习参考 第一种：#include<reg52.h>#define uchar unsigned char#define uint unsigned intuint temp,num,num1;uchar table=0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71,0xff;uchar scan();/ 定义一个键盘扫描函数void delay(uint z)uint x,y;for(x=0;x<z;x+)for(y=0;y&

2、lt;110;y+);void main()P2=0;P0=0x00;while(1)temp=scan();switch(temp)case 0x7e:P0=table0;break;/0按下相应的键显示相对应的码值case 0x7d:P0=table1;break;/1case 0x7b:P0=table2;break;/2 case 0x77:P0=table3;break;/3case 0xbe:P0=table4;break;/4case 0xbd:P0=table5;break;/5case 0xbb:P0=table6;break;/6case 0xb7:P0=table7;br

3、eak;/7 case 0xde:P0=table8;break;/8case 0xdd:P0=table9;break;/9case 0xdb:P0=table10;break;/acase 0xd7:P0=table11;break;/bcase 0xee:P0=table12;break;/c case 0xed:P0=table13;break;/dcase 0xeb:P0=table14;break;/ecase 0xe7:P0=table15;break;/fuchar scan()P3=0x0f;num=P3&0x0f;if(num!=0x0f)delay(10);if(

4、num!=0x0f)num=P3&0x0f;P3=num|0xf0;num1=P3&0xf0;return(num+num1);第二种：#include"reg52.h"#define uchar unsigned char#define uint unsigned intunsigned char code dofly=0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71;/0-Fvoid delay(uint i)/延时函数while(i-);voi

5、d main()P2=0xf8;/1 数码管亮 按相应的按键，会显示按键上的字符P0=dofly0;while(1)uchar key,num;P3=0xef; / 第四列key=P3;key=key&0x0f;while(key!=0x0f)delay(500);key=P3;key=key&0x0f;while(key!=0x0f)key=P3;switch(key)case 0xee: num=12; break;case 0xed: num=13; break;case 0xeb: num=14; break;case 0xe7: num=15; break;while

6、(key!=0x0f)key=P3;key=key&0x0f;P0=doflynum;P3=0xdf; / 第三列key=P3;key=key&0x0f;while(key!=0x0f)delay(500);key=P3;key=key&0x0f;while(key!=0x0f)key=P3;switch(key)case 0xde: num=8; break;case 0xdd: num=9; break;case 0xdb: num=10; break;case 0xd7: num=11; break; while(key!=0x0f)key=P3;key=key&

7、amp;0x0f;P0=doflynum;P3=0xbf; / 第二列key=P3;key=key&0x0f;while(key!=0x0f)delay(500);key=P3;key=key&0x0f;while(key!=0x0f)key=P3;switch(key)case 0xbe: num=4; break;case 0xbd: num=5; break;case 0xbb: num=6; break;case 0xb7: num=7; break;while(key!=0x0f)key=P3;key=key&0x0f;P0=doflynum;P3=0x7f; / 第一列key=P3;key=key&0x0f;while(key!=0x0f)delay(500);key=P3;key=key&0x0f;while(key!=0x0f)key=P3;switch(key)case 0x7e: num=0; break;case 0x7d: num=1; break