main.c(76): error C202: 'key': undefined identifier报错

ID:1077140 · 发表于 2023-9-7 14:24

求助  加了中断之后有报错

单片机源程序如下:
#include "reg52.h"

typedef unsigned int u16;
typedef unsigned char u8;

//定义独立按键控制脚
sbit KEY1=P0^5;                      //A
sbit KEY2=P0^6;                      //B
sbit KEY3=P0^0;                      //感应器
sbit KEY4=P0^4;                      //光栅

//定义LED1控制脚
sbit LED1=P1^0;
sbit LED2=P1^1;

//使用宏定义独立按键按下的键值
#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;//连续扫描按键
      if(key==1&&(KEY1==0||KEY2==0||KEY3==0||KEY4==0))//任意按键按下
      {
            delay_10us(1000);//消抖
            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)       //无按键按下
      {
            key=1;
      }
      return KEY_UNPRESS;
}

void Int1Init()
{
      //设置INT0
      IT1=1;//跳变沿出发方式（下降沿）
      EX1=1;//打开INT0的中断允许。
      EA=1;//打开总中断
}

void main()
{
u8 key=1;
      Int1Init();
      while(1);
      }

void Int1()       interrupt 2
{
      delay_10us(1000);
      if(KEY4==0)
            {
      key=key_scan(0);
               if(key==KEY1_PRESS)
                     LED1=!LED2;
            else if(key==KEY3_PRESS)
                     LED2=!LED2;
            else if(key==KEY2_PRESS)
                     (LED2=!LED2)|(LED1=!LED1);

}
}

main.c(75): error C202: 'key': undefined identifier
main.c(76): error C202: 'key': undefined identifier
main.c(78): error C202: 'key': undefined identifier
main.c(80): error C202: 'key': undefined identifier