Media Recognition Guide - Flash Media

Flash memory is the alternative to byte-programmable memory, which is used by hard, floppy and Zip disks. It is much less expensive, meaning large capacity devices are economically viable and has faster access times and much better shock resistance and durability. Altogether this makes it particularly suitable for use as a portable storage device. Flash memory does have a finite number of write-erase cycles, but manufacturers can guarantee at least 100,000 cycles, which is a much larger number than with byte-programmable memory.

USB Flash Drive

Type:	Flash memory data storage device with USB interface
Introduced:	2000, though the company that invented the device is a legal issue.
Active:	Yes
Cessation:	-
Capacity:	First drive had a capacity of 8 MB but the latest versions can have capacities as large as 256 GB
Compatibility:	Widely supported by modern operating systems including Windows, Mac OS, Linux and Unix systems.
Users:	Broad. Has replaced 3.5” floppy disks as the preferred device for individuals and small organisations for personal data storage, transfer and backup.
File Systems:	FAT, NTFS, HFS+, ext2, ext3
Common manufacturers:	Many manufacturers and brands including Sandisk, Integral, HP, Kingston Technology and Sony

Recognition

USB flash drives can come in a range of shapes and sizes, but as a general rule they measure somewhere in the region of 70mm x 20mm x 10mm and all have a male USB connector at one end. Capacity also varies widely, though the majority of manufacturers specify this either by printing the information on the casing or etching it onto the connector.

Using the word ‘drive’ is misleading as nothing moves mechanically in a USB flash drive. However, they are read and written to by computers in the same way they read and write to disk drives, therefore they are referred to by operating systems as ‘drives’.

The only visible component is the male USB connector, often with a protective cap. Inside the plastic casing is a USB mass storage controller, a NAND flash memory chip and a crystal oscillator to control data output. Some drives also include jumpers and LEDS and a few also have a write-protect switch.

High Level Formatting

USB drives use many of the same file systems as hard disk drives, though it is rare to find a drive that contains a version that pre-dates its creation. Therefore, USB drives most likely contain FAT32, rather than FAT16 or FAT12. FAT32 is the file system most commonly found on USB drives due to its broad compatibility with all major operating systems. NTFS can be used but it is not as reliable when used on operating systems other than Windows. If a drives is intended for a specific operating system, you can expect to find either HFS+ (for Macs) or ext2 or ext3 (for Linux).

Formatting a disk is done in the same way as formatting a floppy disk. If being done on a Windows operating system for example the only difference is you will right click on the USB drive icon, rather than the floppy drive.

FireWire Flash Drive

Type:	Flash memory data storage device with firewire interface
Introduced:	2004
Active:	Yes
Cessation:	-
Capacity:	Either 4, 8 or 16 GB
Compatibility:	Compatible with any computer with a firewire connector
Users:	Limited. Never achieved the same popularity as USB flash drives. They come in smaller sizes and have slower memory
File Systems:	FAT, NTFS, HFS+, ext2, ext3
Common manufacturers:	Kanguru

Recognition

FireWire flash drives look similar and are similar in construction to USB drives, the one difference being that they use a FireWire connector, rather than a USB one. Due to this they have different data transfer rates and capacities than USB drives. Depending on which version of FireWire the drive has been manufactured with it has a transfer rate of either 49.13, 98.25 or 393 MB/s. With the exception of 40.13 MB/s, these rates exceed that of the latest USB version, however they have a much smaller capacity. Furthermore they are heavier and more expensive and fewer computers have the appropriate FireWire connectors compared to those with USB ports. Thus, FireWire flash drives have never dominated the market and are fairly rare.

High Level Formatting

FireWire drives only differ from USB drives in their type of connector, therefore they will contain the same file systems and can be formatted in the same way.