AT89C51单片机8路抢答器的代码怎么写，急用，求解答

#include
#define uchar unsigned char
uchar table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f};
sbit rstkey=P2^2;
sbit speaker=P2^0;
void delay(uchar a)
{
uchar i,j;
for(i=0;ifor(j=0;j<120;j++);
}
main()
{
uchar i,key;
	P2=0xff;
	while(1)
	{
	i=0;
	P1=table[i];
	while(1)
	{
	key=P3;
	if(key!=0)break;
	}
	switch(key)
	{
	case 0x01:i=1;break;
	case 0x02:i=2;break;
	case 0x04:i=3;break;
	case 0x08:i=4;break;
	case 0x10:i=5;break;
	case 0x20:i=6;break;
	case 0x40:i=7;break;
	case 0x80:i=8;break;
	default:break;
	}
	P1=table[i];//显示按下抢答器的号
	P0=key;//显示按下键号的LED
	while(1)
	{
	if(rstkey==0)break;//主持人按下复位键则重新开始
	speaker=~speaker;//否则蜂鸣器报警
	delay(250);
	}
	}
}