这个键盘扫描程序怎么理解(急急急急急!!!!)

来源:百度知道 编辑:UC知道 时间:2024/06/20 13:40:52
#include <reg51.h>
#include <math.h>
#include <intrins.h>
#define uchar unsigned char
#define TURE 1
#define FALSE 0
int key;
int del;
void Tkey(void);
/************主 程序*************/
void main(void)
{
void tkey(void);
void delay(int);

SCON=0x00;
TI=0;
while(TURE)
{
Tkey();
delay(2000);
}

}
void Tkey(void)
{
uchar readkey;//rereadkey;
uchar x_temp,y_temp;

P1=0x0f;
x_temp=P1&0x0f;
if(x_temp==0x0f) goto keyout;
P1=0xf0;
y_temp=P1&0xf0;
readkey=x_temp|y_temp;
readkey=~readkey;

switch(readkey)
{
case 0x11:key=0; break;
case 0x21:key=1; break;
case 0x41:key=2; break;
case 0x81:key=3; break;
case 0x12:key=4; break;
case 0x22:key=5; break;
case 0x42:key=6; break;
case 0x82:key=7; break;
case 0x14:key=8; break;
case 0x24:

你的程序有问题哦!
#include <reg51.h>
#include <math.h>
#include <intrins.h>
#define uchar unsigned char
#define TURE 1
#define FALSE 0
int key;
int del;
void Tkey(void);
/************主 程序*************/
void main(void)
{
void tkey(void);
void delay(int);

SCON=0x00;
TI=0;
while(TURE)
{
Tkey();
delay(2000);
} //这是一个死循环

}
void Tkey(void)
{
uchar readkey;//rereadkey;
uchar x_temp,y_temp;
/*你给出的程序提示你的键盘是4X4的*/

P1=0x0f; //给行送高电平,列送低电平
x_temp=P1&0x0f; //读回行的状态
if(x_temp==0x0f) goto keyout; /*若行中有低电平也即不等于0x0f,
/*表示有键按下
P1=0xf0; //给给列送高电平,行送低电平
y_temp=P1&0xf0; //读回列状态
readkey=x_temp|y_temp; //行状态列状态并起代表一个按键
readkey=~readkey; //取反
switch(rea