//請問為什么在main函數中聲明變量一定要放在最前,詳細的疑問請看程序
#include <reg52.h>
#define uchar unsigned char
#define uint unsigned int
sbit key1 = P3^4;
sbit dula = P2^6;
sbit wela = P2^7;
uchar code table[]={
0x3f, 0x06, 0x5b, 0x4f, 0x66, 0x6d,
0x7d, 0x07, 0x7f, 0x6f, 0x77, 0x7c,
0x39, 0x5e, 0x79, 0x71
};
void main(void)
{
uchar num;//num變量放在這里申明,程序不會出錯,放在下面注釋的位置就會出錯???請大神解釋下
wela = 1;
P0 = 0xfe;
wela = 0;
//uchar num;///////num變量如果是在這里申明;那么程序就會出錯,請問我們在申明main函數中的變量的時候為什么一定要放在第一位?
P3 = 1;
while(1)
{
if(key1 == 0)
{
num++;
}
dula = 1;
P0 = table[num];
dula = 0;
}
}
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