求救！！！关于韦东山的视频，我用linux编译的bin文件执行到延时程序就停了？

int main()
{
        volatile unsigned long dly;
        rGPBCON = (1<<(5*2))| (1<<(6*2))| (1<<(7*2))| (1<<(8*2));
        rGPBDAT = ((1<<5)|(1<<6)|(1<<7)|(1<<8));
    while(1)
    {
            dly=30000;
            rGPBDAT = ~(1<<5);
            for(;dly>0;dly--);
            rGPBDAT = ~(1<<6);
            dly=30000;
            for(;dly>0;dly--);
            rGPBDAT = ~(1<<6);
            dly=30000;
            for(;dly>0;dly--);   
开发板的现象是只有第一个灯常亮着，求解？拜托了···