debug_emifa()   //這是初始化SDRAM的程序，可先不考慮  what's the means??
{/*****************DeBug EMIFA_CE0/SDRAM*************************************/ 
  short myemifa;
 for(myemifa=0;myemifa<100;myemifa++)
 {
 *(unsigned int *)(0x80000000+myemifa*4)=myemifa+100; 
 
 }   
  for(myemifa=0;myemifa<100;myemifa++)
 {
 *(unsigned int *)(0x70000+myemifa*4)=*(unsigned int *)(0x80000000+myemifa*4); 
 
 }   
  }