小白，求大神指点~~

#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char
sbit dula=P2^6;
sbit wela=P2^7;
uchar num;
uchar code table[]={
0x3f,0x06,0x5b,0x4f, 0x66,0x6d,
0x7d,0x07, 0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};
void delay(uint z);
void main() {
wela=1;P0=0xc0;wela=0;
while(1)
{for(num=0;num<16;num++)
{ dula=1;
P0=table[num];
dula=0;
delay(1000);
}
}
}
void delay (uint z)
{ uint x,y;for (x=z;x>0;x--)
for(y=110;y>0;y--);
}
为啥下载不到单片机上，运行不了？？
一打开开关运行的还是上次的程序呀，程序貌似没有错误呀！！
小白求指点！！！