DSTATUS status;
  FRESULT result;
  FATFS FATFS_Obj;

  status = disk_initialize(0);
  if (status == RES_OK)
  {
     result = f_mount(&FATFS_Obj, "0", 1);
     if (result == FR_OK)
      {
          FIL file;
          UINT nRead, nWritten;

          result = f_open(&file, "test.txt", FA_CREATE_ALWAYS | FA_WRITE);
          if (result == FR_OK)
          {
             f_write(&file, "hello", 4, &nWritten);
              f_close(&file);
          }

     }
     }