}
#if (FS_FAT_NOFAT32==0)
  else {
    /* FAT32 */
    /* FATSz32 */
    buffer[36]  = (char)(bpb.FATSz32 & 0xff);
    buffer[37]  = (char)((FS_u32)(bpb.FATSz32 & 0x0000ff00UL) >> 8);
    buffer[38]  = (char)((FS_u32)(bpb.FATSz32 & 0x00ff0000UL) >> 16);
    buffer[39]  = (char)((FS_u32)(bpb.FATSz32 & 0xff000000UL) >> 24);
    /* EXTFlags */
    buffer[40]  = (char)(bpb.ExtFlags & 0xff);
    buffer[41]  = (char)((unsigned int)(bpb.ExtFlags & 0xff00) >> 8);
    /* FSVer = 0:0 */
    buffer[42]  = 0x00;
    buffer[43]  = 0x00;
    /* RootClus */
    buffer[44]  = (char)(bpb.RootClus & 0xff);
    buffer[45]  = (char)((FS_u32)(bpb.RootClus & 0x0000ff00UL) >> 8);
    buffer[46]  = (char)((FS_u32)(bpb.RootClus & 0x00ff0000UL) >> 16);
    buffer[47]  = (char)((FS_u32)(bpb.RootClus & 0xff000000UL) >> 24);
    /* FSInfo */
    buffer[48]  = (char)(bpb.FSInfo & 0xff);
    buffer[49]  = (char)((unsigned int)(bpb.FSInfo & 0xff00) >> 8);
    /* BkBootSec = 0x0006; */
    buffer[50]  = 0x06;
    buffer[51]  = 0x00;
    /* Reserved */
    for (i = 52; i < 64; i++) {
      buffer[i] = (char)0x00;
    }
    /* DrvNum = 0x00 (floppy) */
    buffer[64]  = (char)0x00;
    /* Reserved1 = 0x00 (floppy) */
    buffer[65]  = (char)0x00;
    /* BootSig = 0x00 (next three fields are not 'present') */
    buffer[66]  = (char)0x00;
    /* VolID = 0x00000000 (serial number, e.g. date/time) */
    for (i = 67; i < 71; i++) {
      buffer[i] = (char)0x00;
    }
    /* VolLab = ' ' */
    for (i = 71; i < 82; i++) {
      buffer[i] = (char)0x20;
    }
    /* FilSysType = 'FAT12' */
    FS__CLIB_strncpy(&buffer[82], "FAT32   ", 8);
  }
#endif /* FS_FAT_NOFAT32==0 */
  /* Signature = 0xAA55 */
  buffer[510] = (char)0x55;
  buffer[511] = (char)0xaa;
  /* Write BPB to media */
  i = FS__lb_write(pDriver, Unit, 0, (void*)buffer);
  if (i < 0) {
    FS__fat_free(buffer);
    return -1;
  }
  if (FSysType == 2) {
    /* Write backup BPB */
    i = FS__lb_write(pDriver, Unit, 6, (void*)buffer);
    if (i<0) {
      FS__fat_free(buffer);
      return -1;
    }
  }
  /*  Init FAT 1 & 2   */
  FS__CLIB_memset(buffer, 0x00, (FS_size_t)FS_FAT_SEC_SIZE);
  for (sector = 0; sector < 2 * (bpb.FATSz16 + bpb.FATSz32); sector++) {
    value = sector % (bpb.FATSz16 + bpb.FATSz32);
    if (value != 0) {
      i = FS__lb_write(pDriver, Unit, bpb.RsvdSecCnt + sector, (void*)buffer);
      if (i<0) {
        FS__fat_free(buffer);
        return -1;
      }
    }
  }
  buffer[0] = (char)Media;
  buffer[1] = (char)0xff;
  buffer[2] = (char)0xff;
  if (FSysType != 0) {
    buffer[3] = (char)0xff;
  }
#if (FS_FAT_NOFAT32==0)
  if (FSysType == 2) {
    buffer[4]   = (char)0xff;
    buffer[5]   = (char)0xff;
    buffer[6]   = (char)0xff;
    buffer[7]   = (char)0x0f;
    buffer[8]   = (char)0xff;
    buffer[9]   = (char)0xff;
    buffer[10]  = (char)0xff;
    buffer[11]  = (char)0x0f;
  }
#endif /* FS_FAT_NOFAT32==0 */
  for (i = 0; i < 2; i++) {
    j = FS__lb_write(pDriver, Unit, (FS_u32)bpb.RsvdSecCnt + i * ((FS_u32)bpb.FATSz16+bpb.FATSz32), (void*)buffer);
    if (j < 0) {
      FS__fat_free(buffer);
      return -1;
    }	// two fat table
  }
  /* Init root directory area */
  FS__CLIB_memset(buffer, 0x00, (FS_size_t)FS_FAT_SEC_SIZE);
  if (bpb.RootEntCnt != 0) {
    /* FAT12/FAT16 */
    n = (((FS_u32)bpb.RootEntCnt * 32) / (FS_u32)512);	//n show the sectors accupied by root directory entries
    for (i = 0; i < n; i++) {
      j = FS__lb_write(pDriver, Unit, bpb.RsvdSecCnt + 2 * bpb.FATSz16 + i, (void*)buffer);	//reserved sectors under fat12/16 is 1
      if (j < 0) {
        FS__fat_free(buffer);
        return -1;
      }
    }
  }
#if (FS_FAT_NOFAT32==0)
  else {
    /* FAT32 */
    n = bpb.SecPerClus;
    for (i = 0; i < n; i++) {
      j = FS__lb_write(pDriver, Unit, bpb.RsvdSecCnt + 2 * bpb.FATSz32 + (bpb.RootClus - 2) * n + i, (void*)buffer);
      if (j < 0) {
        FS__fat_free(buffer);
        return -1;
      }
    }
  }
#endif /* FS_FAT_NOFAT32==0 */
#if (FS_FAT_NOFAT32==0)
  if (FSysType == 2) {
    /* Init FSInfo */
    FS__CLIB_memset(buffer, 0x00, (FS_size_t)FS_FAT_SEC_SIZE);
    /* LeadSig = 0x41615252 */
    buffer[0]     = (char)0x52;
    buffer[1]     = (char)0x52;
    buffer[2]     = (char)0x61;
    buffer[3]     = (char)0x41;
    /* StructSig = 0x61417272 */
    buffer[484]   = (char)0x72;
    buffer[485]   = (char)0x72;
    buffer[486]   = (char)0x41;
    buffer[487]   = (char)0x61;
    /* Invalidate last known free cluster count */
    buffer[488]   = (char)0xff;
    buffer[489]   = (char)0xff;
    buffer[490]   = (char)0xff;
    buffer[491]   = (char)0xff;
    /* Give hint for free cluster search */
    buffer[492]   = (char)0xff;
    buffer[493]   = (char)0xff;
    buffer[494]   = (char)0xff;
    buffer[495]   = (char)0xff;
    /* TrailSig = 0xaa550000 */
    buffer[508]   = (char)0x00;
    buffer[509]   = (char)0x00;
    buffer[510]   = (char)0x55;
    buffer[511]   = (char)0xaa;
    i = FS__lb_write(pDriver, Unit, bpb.FSInfo, (void*)buffer);
    if (i < 0) {
      FS__fat_free(buffer);
      return -1;
    }
  }
#endif /* FS_FAT_NOFAT32==0 */
  FS__fat_free(buffer);
  return 0;
}


/*********************************************************************
*
*             _FS_FAT_AutoFormat
*
  Description:
  FS internal function. Get information about the media from the 
  device driver. Based on that informaton, calculate parameters for
  formatting that media and call the format routine.

  Parameters:
  Idx         - Index of device in the device information table 
                referred by FS__pDevInfo.
  Unit        - Unit number.
  
  Return value:
  >=0         - Media has been formatted.
  <0          - An error has occured.
*/

static int _FS_FAT_AutoFormat(int Idx, FS_u32 Unit) {
  struct {
    FS_u32 hiddennum;
    FS_u32 headnum;
    FS_u32 secnum;
    FS_u32 partsize;
  } devinfo;
  FS_u32 rootentcnt;
  FS_u32 fatsz;
  FS_u32 rootdirsectors;
  FS_u32 tmpval1;
  FS_u32 tmpval2;
  FS_u32 fatsz32;
  FS_u32 totsec32;
  FS_u32 resvdseccnt;
  FS_u16 totsec16;
  FS_u16 fatsz16;
  int i;
  unsigned char secperclust;
  char fsystype;

  /* Get info from device */
  devinfo.hiddennum = 0x00001111UL;
  devinfo.headnum   = 0x00002222UL;
  devinfo.secnum    = 0x00003333UL;
  devinfo.partsize  = 0x00004444UL;
  i = FS__lb_ioctl(FS__pDevInfo[Idx].devdriver, Unit, FS_CMD_GET_DEVINFO, 0, (void*)&devinfo);
  if (i) {
    return -1;
  }
  /* Check if the driver really supports FS_CMD_GET_DEVINFO */
  if (devinfo.hiddennum == 0x00001111UL) {
    if (devinfo.headnum == 0x00002222UL) {
      if (devinfo.secnum == 0x00003333UL) {
        if (devinfo.partsize == 0x00004444UL) {
          return -1;
        }
      }
    }
  }
  if (devinfo.partsize <= 1048576UL) {
    fsystype = 1;   /* FAT16 */
  }
#if (FS_FAT_NOFAT32==0)
  else {
    fsystype = 2;   /* FAT32 */
  }
#else
  else {
    /* FAT32 disabled */
    return -1;
  }
#endif /* FS_FAT_NOFAT32==0 */

  /* Set correct RootEntCnt & ResvdSecCnt */ 
  if (fsystype != 2) {
    /* FAT16 */
    i = 0;
    while (_FS_auto_rootcnt[i].SecNum < devinfo.partsize) {
      i++;
    }
    rootentcnt = (FS_u16)_FS_auto_rootcnt[i].Num;
    resvdseccnt = 1;
  }
#if (FS_FAT_NOFAT32==0)
  else {
    /* FAT32 */
    rootentcnt = 0;
    resvdseccnt = 0x20;
  }
#endif /* FS_FAT_NOFAT32==0 */

  /* Determinate SecPerClust */
  i = 0;
  while (_FS_auto_secperclust[i].SecNum < devinfo.partsize) {
    i++;
  }
  secperclust = (unsigned char) _FS_auto_secperclust[i].Num;
  /* 
     FAT16/FAT32 FAT size calculation 
     The formula used is following the Microsoft specification
     version 1.03 very closely. Therefore the calculated FAT
     size can be up to 8 sectors bigger than required for the 
     media. This is a waste of up to 8 sectors, but not a problem
     regarding correctness of the media's data.
  */
  rootdirsectors = ((rootentcnt * 32 ) + 511) / 512;
  tmpval1 = devinfo.partsize - (resvdseccnt + rootdirsectors);
  tmpval2 = (256 * secperclust) + 2;
#if (FS_FAT_NOFAT32==0)
  if (fsystype == 2) {
    tmpval2 = tmpval2 / 2;
  }
#endif /* FS_FAT_NOFAT32==0 */
  fatsz = (tmpval1 + (tmpval2 - 1)) / tmpval2;
  if (fsystype != 2) {
    fatsz16 = (FS_u16)fatsz;
    fatsz32 = 0;
  }
#if (FS_FAT_NOFAT32==0)
  else {
    fatsz16 = 0;
    fatsz32 = fatsz;
  }
#endif /* FS_FAT_NOFAT32==0 */

  /* Number of total sectors (512 byte units) of the media
     This is independent of FAT type (FAT12/FAT16/FAT32) */
  if (devinfo.partsize < 0x10000UL) {
    totsec16 = (FS_u16)devinfo.partsize;
    totsec32 = 0;
  }
  else {
    totsec16 = 0;
    totsec32 = devinfo.partsize;
  }
  /* Format media using calculated values */
  i = _FS_fat_format(FS__pDevInfo[Idx].devdriver,
                        Unit,
                        secperclust,
                        (FS_u16)rootentcnt,
                        totsec16,
                        totsec32,
                        (char)0xf8,
                        fatsz16,
                        fatsz32,
                        (FS_u16)devinfo.secnum,
                        (FS_u16)devinfo.headnum,
                        devinfo.hiddennum,
                        fsystype);
  return i;
}

#endif /* FS_FAT_NOFORMAT==0 */


#if FS_FAT_DISKINFO

/*********************************************************************
*
*             _FS_fat_GetTotalFree
*