51单片机独立按键
#include "reg52.h"typedef unsigned char u8;
typedef unsigned int u16;
sbit KEY1=P3^1;
sbit KEY2=P3^0;
sbit KEY3=P3^2;
sbit KEY4=P3^3;
sbit LED1=P2^0;
#define KEY1_PRESS 1
#define KEY2_PRESS 2
#define KEY3_PRESS 3
#define KEY4_PRESS 4
#define KEY_UNPRESS 0
void delay_10us(u16 ten_us)
{
while(ten_us--);
}
u8 key_scan(u8 mode)
{
static u8 key=1;
if(mode)key=1;
if(key=1&&(KEY1==0||KEY2==0||KEY3==0||KEY4==0))
{
delay_10us(1000);
key=0;
if(KEY1==0)
return KEY1_PRESS;
else if(KEY2==0)
return KEY2_PRESS;
else if(KEY3==0)
return KEY3_PRESS;
else if(KEY4==0)
return KEY4_PRESS;
}
else if(KEY1==1&&KEY2==1&&KEY3==1&&KEY4==1)
{
key=1;
}
return KEY_UNPRESS;
}
void main()
{
u8 key=0;
while(1)
{
key=key_scan(0);
if(key==KEY1_PRESS)
LED1=!LED1;
}
}
实验结果不是按一下亮按一下灭，请问问题出在哪里
页:
[1]