平顶山网站建设电话网站内容页相关性怎么做
矩阵键盘:

这个矩阵键盘可以接到P0、P1、P2、P3都是可以的。
使用矩阵键盘是能节省单片机的IO口。

P3.0 P3.1 P3.2 P3.3 称之为行号。
P3.4 P3.5 P3.6 P3.7 称之为列号。
矩阵键盘检测原理:
1、检查是否有键按下;
2、键的抖动处理;
3、查询按下键所在行和列的位置,并对行号和列号译码,得到键值。

#include<reg52.h>#define uchar unsigned char
#define uint unsigned intsbit dula=P2^6;
sbit wela=P2^7;uchar disnum,temp,key;uchar code table_duan[]={
0x3f,0x06,0x5b,0x4f,0x66,0x6d,
0x7d,0x07,0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71,0};void delay(uchar);void main()
{disnum=16;wela=1;P0=0xfe;wela=0;while(1){P3=0xf0;temp=P3;temp=temp&0xf0; //按位与if(temp!=0xf0)  //判断是否有按键按下{delay(10);if(temp!=0xf0){temp=P3;temp=temp|0x0f;P3=temp;key=P3;switch(key){case 0xee: disnum=0; break;case 0xde: disnum=1; break;case 0xbe: disnum=2; break;						case 0x7e: disnum=3; break;						case 0xed: disnum=4; break;						case 0xdd: disnum=5; break;						case 0xbd: disnum=6; break;						case 0x7d: disnum=7; break;						case 0xeb: disnum=8; break;						case 0xdb: disnum=9; break;						case 0xbb: disnum=10; break;						case 0x7b: disnum=11; break;						case 0xe7: disnum=12; break;						case 0xd7: disnum=13; break;						case 0xb7: disnum=14; break;						case 0x77: disnum=15; break;}}	}P0=table_duan[disnum];dula=1;dula=0;}
}void delay(uchar x)
{uchar a, b;for(a=x;a>0;a--){for(b=200;b>0;b--);}	
} 
 
使用子模块(函数)的方法:
#include<reg52.h>#define uchar unsigned char
#define uint unsigned intsbit dula=P2^6;
sbit wela=P2^7;uchar disnum,temp,key,num;void delay(uchar);
uchar keyscan();uchar code table_duan[]={
0x3f,0x06,0x5b,0x4f,0x66,0x6d,
0x7d,0x07,0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71,0};void main()
{disnum=16;wela=1;P0=0xfe;wela=0;while(1){num=keyscan();P0=table_duan[num];dula=1;dula=0;}
}uchar keyscan()
{P3=0xf0;temp=P3;temp=temp&0xf0; //按位与if(temp!=0xf0)  //判断是否有按键按下{delay(10);if(temp!=0xf0){temp=P3;temp=temp|0x0f;P3=temp;key=P3;switch(key){case 0xee: disnum=0; break;case 0xde: disnum=1; break;case 0xbe: disnum=2; break;						case 0x7e: disnum=3; break;						case 0xed: disnum=4; break;						case 0xdd: disnum=5; break;						case 0xbd: disnum=6; break;						case 0x7d: disnum=7; break;						case 0xeb: disnum=8; break;						case 0xdb: disnum=9; break;						case 0xbb: disnum=10; break;						case 0x7b: disnum=11; break;						case 0xe7: disnum=12; break;						case 0xd7: disnum=13; break;						case 0xb7: disnum=14; break;						case 0x77: disnum=15; break;}}	}return disnum;	
}void delay(uchar x)
{uchar a, b;for(a=x;a>0;a--){for(b=200;b>0;b--);}	
} 
光看不练,就是眼高手低。多练习才行的。
