main.c

4*4键盘

/*列扫描法*/
#include<reg51.h>
const int LEDCode[16]={0x40,0x79,0x24,0x30,0x19,0x12,0x02,0x78,0x00,0x10,0x08,0x03,0x46,0x21,0x06,0x0e};
void main()
{
	unsigned int Code;
	P3 = 0xf0;
	P1 = 0x0f;
while(1)
{
  if(P1!=0x0f)
    {
        P1=0xef;
     	if(P1!=0xef)
		  {
	        Code = P1;
			goto display;
		  }
		P1=0xdf;
     	if(P1!=0xdf)
		  {
	        Code = P1;
			goto display;
		  }
		P1=0xbf;
     	if(P1!=0xbf)
		  {
	        Code = P1;
			goto display;
		  }
		P1=0x7f;
     	if(P1!=0x7f)
		  {
	        Code = P1;
		  }
    }
display:
	switch (Code)
	{
		case(0xee):P2 = LEDCode[0];break;
		case(0xed):P2 = LEDCode[1];break;	
		case(0xeb):P2 = LEDCode[2];break;
		case(0xe7):P2 = LEDCode[3];break;
		case(0xde):P2 = LEDCode[4];break;	
		case(0xdd):P2 = LEDCode[5];break;
		case(0xdb):P2 = LEDCode[6];break;
		case(0xd7):P2 = LEDCode[7];break;
		case(0xbe):P2 = LEDCode[8];break;
		case(0xbd):P2 = LEDCode[9];break;
		case(0xbb):P2 = LEDCode[10];break;
		case(0xb7):P2 = LEDCode[11];break;
		case(0x7e):P2 = LEDCode[12];break;
		case(0x7d):P2 = LEDCode[13];break;
		case(0x7b):P2 = LEDCode[14];break;
		case(0x77):P2 = LEDCode[15];break;
	}
}
}