The new system used a different recording format that stored up to 250¼ kB on the same disks. In 1976, media supplier Information Terminals Corporation enhanced resilience further by adding a Teflon coating to the magnetic disk itself. A significant feature of IBM's read/write disk media was the use of a Teflon-lubricated fabric liner to lengthen media life. In 1973, IBM shipped its first read/write floppy disk drive, the 33FD, as a component of the 3740 Data Entry System, code named "IGAR", designed to directly replace IBM's punched card ("keypunch") data entry machines. The Memorex disk was "hard-sectored", that is, it contained 8 sector holes (plus one index hole) at the outer diameter (outside data track 00) to synchronize the beginning of each data sector and the beginning of a track. The 650 had a data capacity of 175 kB, with 50 tracks, 8 sectors per track, and 448 bytes per sector. Internally IBM used another device, code named Mackerel, to write boot disks for distribution to the field.Īlan Shugart left IBM and moved to Memorex where his team shipped the Memorex 650 in 1972, the first commercially available read-write floppy disk drive. and then as a standard part of most System 370 processing units and other IBM products. The new device, developed under the code name Minnow, first shipped in 1971 as the 23FD, the program load component of the 2835 Storage Control Unit. IBM introduced the diskette commercially in 1971. The original disk was bare, but dirt became a serious problem so they enclosed it in a plastic envelope lined with fabric that would remove dust particles. Noble's team developed a read-only, 8-inch-diameter (200 mm) flexible diskette they called the "memory disk", holding 80 kilobytes of data. Noble, who tried to develop a new-style tape for the purpose, but without success. IBM Direct Access Storage Product Manager, Alan Shugart, assigned the job to David L. IBM also wanted inexpensive media that could be sent out to customers with software updates. The System/370 was IBM's first computer system family to make extensive usage of volatile read/write semiconductor memory for microcode, so for most models, whenever the power was turned on, the microcode had to be loaded (System/370's predecessor, System/360, generally used non-volatile read-only memory for microcode). In 1967, IBM tasked their San Jose, California storage development center to develop a reliable and inexpensive system for loading microcode into their System/370 mainframes in a process called Initial Control Program Load (ICPL). While floppy disk drives still have some limited uses, especially with legacy industrial computer equipment, they have been superseded by data storage methods with much greater capacity such as USB flash drives, portable external hard disk drives, optical discs, memory cards, and computer networks. This fadeout was already on its way in the mid-1990s, as noted by a 1994 "Floppy disk drive prices falling" headline on an article that began "Floppy disk drive revenues are falling down and they can't get up." Low-cost floppy drives became indispensable for word processors and PCs.įloppy disks remained a popular portable digital-storage medium for nearly 40 years. A number of varient sizes with limited market success were also available. First introduced into the market as 8-inch floppy disks in 1972, they were followed by 5¼-inch disks in 1976 and 3½-inch disks in 1982. Work on the drive for what became the media of "the world's first" floppy disk drive began in 1967 at a San Jose (CA) IBM facility. A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, readable by a floppy disk drive (FDD), and sealed in a rectangular plastic carrier lined with fabric which serves the purpose of keeping the data storage disk free of foreign particles such as dust.
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