编码键盘输出.c

这是键盘接收处理子程序。可以当作通用程序使用

/*
	WRITE FROM CHAO-JEN HUANG
	DATE: 2004-04-30
	PROGRAM: Keil uVision C51
*/
#include <reg51.h>

sbit P3_0 = 0xB0;			//DEFINE P3.0
sbit P3_1 = 0xB1;			//DEFINE P3.1
sbit P3_2 = 0xB2;			//DEFINE P3.2
sbit P3_3 = 0xB3;			//DEFINE P3.3

void delay();				//DELAY

void main(void)
{
	while(1)
	{
		P1=0xbf;
		P3=0x7f;		//SCAN FIRST COLUMN
		if(P3_3==0)		//SHOW 0
		{
			P1=0xc0;
			delay();
			while(P3_3==0);
		}
		else if(P3_2==0)	//SHOW 1
		{
			P1=0xf9;
			delay();
			while(P3_2==0);
		}
		else if(P3_1==0)	//SHOW 2
		{
			P1=0xa4;
			delay();
			while(P3_1==0);
		}
		else if(P3_0==0)	//SHOW 3
		{
			P1=0xb0;
			delay();
			while(P3_0==0);
		}
		P3=0xbf;		//SCAN SECOND COLUMN
		if(P3_3==0)		//SHOW 4
		{
			P1=0x99;
			delay();
			while(P3_3==0);
		}
		else if(P3_2==0)	//SHOW 5
		{
			P1=0x92;
			delay();
			while(P3_2==0);
		}
		else if(P3_1==0)	//SHOW 6
		{
			P1=0x82;
			delay();
			while(P3_1==0);
		}
		else if(P3_0==0)	//SHOW 7
		{
			P1=0xf8;
			delay();
			while(P3_0==0);
		}
		P3=0xdf;		//SCAN THIRD COLUMN
		if(P3_3==0)		//SHOW 8
		{
			P1=0x80;
			delay();
			while(P3_3==0);
		}
		else if(P3_2==0)	//SHOW 9
		{
			P1=0x90;
			delay();
			while(P3_2==0);
		}
		else if(P3_1==0)	//SHOW A
		{
			P1=0x88;
			delay();
			while(P3_1==0);
		}
		else if(P3_0==0)	//SHOW B
		{
			P1=0x83;
			delay();
			while(P3_0==0);
		}
		P3=0xef;		//SCAN FOUTH COLUMN
		if(P3_3==0)		//SHOW C
		{
			P1=0xc6;
			delay();
			while(P3_3==0);
		}
		else if(P3_2==0)	//SHOW D
		{
			P1=0xa1;
			delay();
			while(P3_2==0);
		}
		else if(P3_1==0)	//SHOW E
		{
			P1=0x86;
			delay();
			while(P3_1==0);
		}
		else if(P3_0==0)	//SHOW F
		{
			P1=0x8e;
			delay();
			while(P3_0==0);
		}
	}
}

void delay()				//DELAY 10MS
{
	int i, j;
	for(i=0;i<25;i++)
	{
		for(j=0;j<200;j++);
	}
}