Formatting

USB Flash Drives All USB Flash Drives
1

I tried using cmd to format the Scandisk cruzer blade 4gb when the format option in the dialogue when u right click the said drive couldnt help formatting… Please is there any other method i can use. thanks

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\Users\Administrator>diskpart

Microsoft DiskPart version 6.1.7601
Copyright (C) 1999-2008 Microsoft Corporation.
On computer: ICT-PC

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  —  —
  Disk 0    Online          465 GB  1024 KB
  Disk 1    Online           64 MB      0 B

DISKPART> select disk 1

Disk 1 is now the selected disk.

DISKPART> clean

DiskPart succeeded in cleaning the disk.

DISKPART> create partition primary

No usable free extent could be found. It may be that there is insufficient
free space to create a partition at the specified size and offset. Specify
different size and offset values or don’t specify either to create the
maximum sized partition. It may be that the disk is partitioned using the MBR di
sk
partitioning format and the disk contains either 4 primary partitions, (no
more partitions may be created), or 3 primary partitions and one extended
partition, (only logical drives may be created).

DISKPART>

2

Try RMPrepUSB.

http://www.rmprepusb.com/tutorials/54—how-to-fix-write-protected-disks

To replace the drive:

http://kb.sandisk.com/app/answers/detail/a_id/5232/~/return-material-authorization-(rma)-process

3

yes, i have the same problem, anybody have solution???

4

Why are you trying to format the drive?

8

hi @itmichael I’m implementing the SD FAT32 file system without CPU involved so i took using 8GB SD card and i formatted as FAT32 and i check the FAT32 structure fields values
And again i took 16 GB SD card card and i did same which i done in 8GB card that time i got some fields values were different So could you please tell me how these values will vary wrt disk size and what is the calculation to calculate this?
Thanks And Regards,
Vinayak

9

The FAT32 file system uses a File Allocation Table (FAT) to manage file storage on the disk. The structure of the FAT32 file system and the values in its fields can vary depending on the size of the disk or partition. Here’s a general overview of how these values can vary with disk size and the calculation involved:

1.Cluster Size (Allocation Unit Size):

  • The cluster size is the smallest unit of disk space that the file system can allocate to hold a file. Larger disks typically have larger cluster sizes to efficiently manage disk space.
  • Calculation: Cluster size = 2^n bytes, where ‘n’ is the value specified during formatting. For example, a cluster size of 4KB would be 2^12 bytes.

2. Number of Clusters:

  • The total number of clusters depends on the size of the disk and the cluster size. Larger disks can accommodate more clusters.
  • Calculation: Total clusters = (Disk size in bytes) / (Cluster size)

3. FAT (File Allocation Table):

  • The FAT is a data structure that maps each cluster on the disk to its corresponding status (e.g., free, allocated, end of file). The size of the FAT can vary based on the number of clusters.
  • Calculation: FAT size = (Number of clusters) * (FAT entry size)

4. Root Directory Entries:

  • The root directory is a special directory at the beginning of the disk that stores information about files and directories in the root of the file system. The number of entries in the root directory can vary.
  • Calculation: Root directory entries = (Disk size) / (Cluster size) / (Entries per cluster)

5. FAT Entry Size:

  • The size of each FAT entry can vary depending on the total number of clusters. Larger disks may require more bits to represent each cluster.
  • Calculation: FAT entry size = (Total clusters) * (bits per FAT entry)

6. Total Sectors and Size:

  • The total number of sectors on the disk and the disk size in bytes are also important values that can vary with disk size.
  • Calculation: Total sectors = (Disk size in bytes) / (Sector size), Disk size = (Total sectors) * (Sector size)

These calculations are approximate and may vary slightly depending on the specific implementation of the FAT32 file system and the formatting tool used. Different operating systems and formatting utilities may also have variations in how they calculate and set these values during formatting.

For precise calculations and detailed information about FAT32 structures, you may refer to the FAT32 file system specification or consult the documentation of the formatting tool you are using.