51单片机的数码管跟矩阵键盘

使用4*4的矩阵键盘和一个数码管

在4*4的矩阵键盘上编码0-F的字符，和一个数码管显示每个键盘上输入的字符。

//4*4键盘检测程序,按下键后相应的代码显示在数码管上#include<reg51.h>typedef unsigned char UINT8;UINT8 i=100;UINT8 j,k,temp,key;void delay(unsigned char i){  for(j=i;j>0;j--)    for(k=125;k>0;k--);}UINT8 code table[]={	0x3f,0x06,0x5b,0x4f,	0x66,0x6d,0x7d,0x07,	0x7f,0x6f,0x77,0x7c,	0x39,0x5e,0x79,0x71};void display(unsigned char num){     P0=table[num];}void init_led(){	P0 = 0x00;}                                                                                                     void main(){	while(1)	{  		P1 = 0xef;		temp = P1;		temp = temp&0xf0;		if (temp != 0xf0)		{			temp = P1;			switch(temp)			{				  case 0xee:					   key=0;					   break;				  case 0xed:					   key=1;					   break;				  case 0xeb:					   key=2;					   break;				  case 0xe7:					   key=3;					   break;				  default:					  					  break;			}			display(key);			P1=0xfe;		}		P1 = 0xdf;		temp = P1;		temp = temp&0x0f;		if(temp != 0x0f)		{			temp = P1;			switch(temp)			{				  case 0xde:					   key = 4;					   break;				  case 0xdd:					   key = 5;					   break;				  case 0xdb:					   key = 6;					   break;				  case 0xd7:					   key = 7;					   break;				  default:					  break;			 }			 display(key);		}		P1=0xbf;		temp=P1;		temp=temp&0x0f;		if(temp != 0x0f)		{			temp=P1;			switch(temp)			{				  case 0xbe:					   key=8;					   break;				  case 0xbd:					   key=9;					   break;				  case 0xbb:					   key=10;					   break;				  case 0xb7:					   key=11;					   break;				  default:					   break;			}			display(key);		}		P1=0x7f;		temp=P1;		temp=temp&0x0f;		if(temp!=0x0f)		{		  			temp=P1;			switch(temp)			{				  case 0x7e:					   key=12;					   break;				  case 0x7d:					   key=13;					   break;				  case 0x7b:					   key=14;					   break;				  case 0x77:					   key=15;					   break;				  				  default:					  break;			}			display(key);		}	}	}