SuperDisk

Also known as the LS-120 and the later variant LS-240, the SuperDisk was introduced by 3M's storage products group (later known as Imation) circa 1997 as a high-speed, high-capacity alternative to the 90 mm (3.5 in), 1.44 MB floppy disk. SuperDisk's main claim to fame was that in addition to being able to read and write its native 120 MB (later 240 MB) disks, the drives could read and write the 1.44 MB and 720 KB floppy formats (MFM) that were still popular at the time. They also seemed to read and write faster to these sorts of disks than conventional 1.44 MB or 720 KB floppy drives. The newer LS-240 drives also have the ability to read and write regular 1.44 MB floppies at much higher densities.

The true capacity of these "100 MB" drives is 120.375 MB (6848 cylinders × 36 blocks/cylinder × 512 bytes [http://linuxcommand.org/man_pages/floppy8.html] ). The "240 MB" drives have a true capacity of 240.750 MB.

The design of the SuperDisk system came from an early 1990s project at Iomega. It is one of the last examples of Floptical technology, where lasers are used to guide a magnetic head which is much smaller than those used in traditional floppy disk drives. Iomega orphaned the project around the time they decided to release the Zip drive in 1994. The idea eventually ended up at 3M, where the concept was refined and the design was licensed to established floppy drive makers Matsushita (Panasonic) and Mitsubishi. Other companies involved in the development of SuperDisk included Compaq and OR Technology.

Imation mainly sold Matsushita-built drives under the SuperDisk name; other companies tended to use the LS-120 name, and sold the Mitsubishi drives. However, the system was not a huge success. Few OEMs supported it, aside from Compaq. Most SuperDisk drives suffered from slow performance and reliability problems (the disks were quite fragile and broke easily, even when exercising utmost care during usage). Fact|date=June 2008The biggest hurdle standing in the way of success was that Iomega's Zip drive had been out for 3 years at that point. It had enough popularity to leave the public uninterested in SuperDisk technology despite its superior design and its compatibility with the standard floppy disk.

By 2000, the entire removable-disk category quickly faced obsolescence by the falling prices of CD-R and CD-RW drives and in 2006 solid-state (USB flash drives or USB keydrives), and the SuperDisk was no exception; it has since been quietly discontinued, as were the other special disks, which are getting hard to find.

Matsushita continued development of the technology and released the LS-240, which was still fairly available in Asia and Australia until 2003 but is now quite rare. It has double the capacity and the added feature of being able to format regular floppy disks to 32 MB capacity . However, this higher density comes at a price—the entire disk must be rewritten any time a change is made, much like early CD-RW media.

SuperDisk drives have been sold in parallel port, USB, ATAPI and SCSI variants. All drives can read and write 1.44 MB (1440 KB) and 720 KB MFM floppies, as used on PCs, Apple Macintoshes (High Density format only, see below), and many workstations.

Under Windows XP, a USB-based SuperDisk drive will appear as a 3.5" floppy disk drive, receiving either the drive letter A: (if there is no floppy in the machine) or B: (if there already is one). This enables use by software that expects a floppy drive when 1.44MB or 720KB disks are inserted. 120MB disks are also accessed via A: or B:.

One problem faced by Apple Macintosh users was, however, that the SuperDisk drive cannot read the GCR 800K or 400K diskettes used by older Macintoshes. These disks could be used in the SuperDisk drive on a Mac, but only if formatted to PC 720K MFM format.

Imation also released a version of the SuperDisk with "Secured Encryption Technology" which uses Blowfish with a 64 bit key to encrypt the contents.

SuperDisk should not be confused with SuperDrive, which is a trademark used by Apple Computer for various disk drive products.

A SuperDisk drive was used in two Panasonic digital cameras, the PV-SD4090 and PV-SD5000, which allowed them to use both SuperDisk (LS120) and 3.5" floppy disks as the memory media.

References

External links

*http://www.itreviews.co.uk/hardware/h97.htm
*http://www.itreviews.co.uk/hardware/h309.htm
*http://markhobley.yi.org/linux/howto/ls120/