单片机 EA=1； 错误

#include<reg52.h> sbit wei=P2^7; sbit duan=P2^6; sbit d1=P1^0; sbit beep=P2^3; unsigned char code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c, 0x39,0x5e,0x79,0x71,0x00}; void main() { EA=1; EX0=1; unsigned char num; unsigned int a=10000; wei=1;P0=0x2a;wei=0; for(num=0;num<16;num++) { duan=1;P0=table[num];duan=0; while(a--); } } void exter0() interrupt 0 { d1=0; beep=0; } 去掉EA=1;EX0=1编译没有错误，没去掉就会出现7个错误！为什么？？

C51语法，变量定语要在当前函数或程序块中的开头部分
unsigned char num;unsigned int a=10000;
移到前边, EA=1;EX0=1;放定义变量之后
或者加花括号:
void main()
{
EA=1;
EX0=1;
{
unsigned char num;
unsigned int a=10000;
wei=1;P0=0x2a;wei=0;
for(num=0;num<16;num++)
{ duan=1;P0=table[num];duan=0;
while(a--);
}
}
}

C 语言需要先定义变量, 再赋值 把语句 EA=1; EX0=1; 放到 unsigned int a=10000; 语句之后

unsigned char num; // 定义要放在前面 试试 unsigned int a=10000; EA=1; EX0=1;

#include<reg52.h> sbit wei=P2^7; sbit duan=P2^6; sbit d1=P1^0; sbit beep=P2^3; unsigned char code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c, 0x39,0x5e,0x79,0x71,0x00}; void main() { unsigned char num; unsigned int a=10000; EA=1; EX0=1; wei=1;P0=0x2a;wei=0; for(num=0;num<16;num++) { duan=1;P0=table[num];duan=0; while(a--); } } void exter0() interrupt 0 { d1=0; beep=0; }