SD卡读扇区前127个可以读后面的不能读问题

zlj644

各位兄弟姐妹们，能不能帮我一个忙啊，小弟在用SPI读SD卡式，出现一个问题，前面的127个扇区可用正常读写，但是128及以后的扇区就不能读写了，不知道为什么啊！
ret=SD_Rd_Block(DBUF, 128);
返回值是255
源程序如下，请教高人指点啊！  先谢谢了！
byte SD_Rd_Block(Uint16 *buff, unsigned long address)
{
        Uint16 count;
  //Block size is 512 bytes exactly
  //First Lower SS
    byte resp;
  SD_Assert();
  //Then send write command
  SD_Wt_Cmd(0x11,address<<9,0xff);
  resp=SD_Rd_Resp();
  if(resp!=0)
  return resp;
    //command was a success - now send data
    //start with DATA TOKEN = 0xFE
    while(SD_Rd_Byte()!=0xfe);

    for(count=0;count<128;count++)
    {
            *buff|=(Uint16)(SD_Rd_Byte()<<8);
                  *buff|= (Uint16)(SD_Rd_Byte());
                *buff++;
            *buff|=(Uint16)(SD_Rd_Byte()<<8);
                  *buff|=(Uint16)(SD_Rd_Byte());
                *buff++;
    }
    //data block sent - now send checksum
    SD_Rd_Byte();
    SD_Rd_Byte();
    //Now read in the DATA RESPONSE token
    SD_deAssert();//SD_CS=1
    SD_Rd_Byte();
    return 1;
//  printf("Command 0x11 (Read) was not received by the MMC.\n");
}

zlj644

哎，发帖从来没被人回过，杯具啊

zlj644

结帖，不问了，呵呵，自己解决