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91-539: The portable has a special high-resolution 640 × 400 display mode which is similar to and partially compatible with the Olivetti/AT&;T 6300 graphics. The base model has 640 KB memory. There is a single proprietary expansion slot for 1200 bit/s modem, expansion chassis for 5x 8-bit ISA cards, Ethernet NIC , 2400 bit/s modem, and a 2 MB memory card (thus 2.6 MB in max total). T3100e model has 1 MB of memory, which can be upgraded to 5 MB. Toshiba T3100

182-756: A computer or other device. The first floppy disks, invented and made by IBM in 1971, had a disk diameter of 8 inches (203.2 mm). Subsequently, the 5¼-inch (133.35 mm) and then the 3½-inch (88.9 mm) became a ubiquitous form of data storage and transfer into the first years of the 21st century. 3½-inch floppy disks can still be used with an external USB floppy disk drive. USB drives for 5¼-inch, 8-inch, and other-size floppy disks are rare to non-existent. Some individuals and organizations continue to use older equipment to read or transfer data from floppy disks. Floppy disks were so common in late 20th-century culture that many electronic and software programs continue to use save icons that look like floppy disks well into

273-443: A button that, when pressed, ejects the disk with varying degrees of force, the discrepancy due to the ejection force provided by the spring of the shutter. In IBM PC compatibles , Commodores, Apple II/IIIs, and other non-Apple-Macintosh machines with standard floppy disk drives, a disk may be ejected manually at any time. The drive has a disk-change switch that detects when a disk is ejected or inserted. Failure of this mechanical switch

364-581: A cost—with all software licenses included—on par with the IBM PC/AT with MS-DOS alone. A review in PC Magazine declared that AT&T's 6300 Plus was "flat out the better machine" compared to the IBM PC/AT. The version of Simultask included with the 6300 Plus was based on Locus Computing Corporation 's Merge software . In order to allow MS-DOS applications to run as "concurrent UNIX tasks",

455-650: A customized operating system is used that has no drivers for USB devices. Hardware floppy disk emulators can be made to interface floppy-disk controllers to a USB port that can be used for flash drives. In May 2016, the United States Government Accountability Office released a report that covered the need to upgrade or replace legacy computer systems within federal agencies. According to this document, old IBM Series/1 minicomputers running on 8-inch floppy disks are still used to coordinate "the operational functions of

546-428: A disk can be accessed, the drive needs to synchronize its head position with the disk tracks. In some drives, this is accomplished with a Track Zero Sensor, while for others it involves the drive head striking an immobile reference surface. In either case, the head is moved so that it is approaching track zero position of the disk. When a drive with the sensor has reached track zero, the head stops moving immediately and

637-474: A disk, some 3½-inch drives (notably the Macintosh External 400K and 800K drives ) instead use Constant Linear Velocity (CLV), which uses a variable speed drive motor that spins more slowly as the head moves away from the center of the disk, maintaining the same speed of the head(s) relative to the surface(s) of the disk. This allows more sectors to be written to the longer middle and outer tracks as

728-441: A fixed black background), but could be expanded to 4 or 8 colours/greyscales in all resolutions, and 16 in all but 512×256, with the addition of a graphics memory expansion board holding between 32 and 96 KB RAM (the resolution:colour relationship being unintuitive due to Motorola HD6845 CRTC bandwidth and addressing limitations - 16 colours in the 640-pixel modes effectively combined the standard and expansion memory spaces into

819-413: A hard-sectored disk, there are many holes, one for each sector row, plus an additional hole in a half-sector position, that is used to indicate sector zero. The Apple II computer system is notable in that it did not have an index hole sensor and ignored the presence of hard or soft sectoring. Instead, it used special repeating data synchronization patterns written to the disk between each sector, to assist

910-420: A loaded disk can be removed manually by inserting a straightened paper clip into a small hole at the drive's front panel, just as one would do with a CD-ROM drive in a similar situation. The X68000 has soft-eject 5¼-inch drives. Some late-generation IBM PS/2 machines had soft-eject 3½-inch disk drives as well for which some issues of DOS (i.e. PC DOS 5.02 and higher) offered an EJECT command. Before

1001-468: A maximum speed of exactly the same 10 MHz. To support this, the motherboard now featured a switchable 24/30 MHz master crystal, still divided by 3 to produce the 33% duty CPU clock, with an additional 4 MHz crystal to maintain that clock signal for peripherals that required it, and the video board receiving its own 24 MHz crystal to maintain the same image size and scan frequencies at both processor speeds. In October 1985, AT&T launched

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1092-504: A moderate level of support from software developers, mostly for "serious" applications such as Lotus 1-2-3 and Symphony ( Earl Weaver Baseball is however an example of a game that can use it), and was for a time both supported and emulated (as well as extended to e.g. 752x410) by various "Super EGA "/"any mode on any monitor" cards such as the ATI EGA Wonder . These, as well as any other replacement video card, could be used in

1183-426: A non-standard hardware unit known as OS Merge was provided, allowing DOS applications to "think" that they had "complete control over the system" and offering "almost complete compatibility with IBM PC software", with a reported performance penalty when running applications such as Microsoft Flight Simulator of around 15 percent. Such additional hardware was necessary to support these virtualisation features due to

1274-439: A poorly documented 512×256 mode for compatibility with the earlier M20 model (in conjunction with a Z8000 -based emulator card that included a necessary additional clock source). All modes were non-interlaced , albeit running at a then-common 50 Hz Vsync rate, and required the dedicated OEM 26.3 kHz, 12" monitor (either colour or multi-level monochrome) because of their comparatively high line frequency, with all but

1365-557: A recovery. The music and theatre industries still use equipment requiring standard floppy disks (e.g. synthesizers, samplers, drum machines, sequencers, and lighting consoles ). Industrial automation equipment such as programmable machinery and industrial robots may not have a USB interface; data and programs are then loaded from disks, damageable in industrial environments. This equipment may not be replaced due to cost or requirement for continuous availability; existing software emulation and virtualization do not solve this problem because

1456-468: A selectable option and purchasable as an aftermarket OEM add-on. By January 2007, only 2% of computers sold in stores contained built-in floppy disk drives. Floppy disks are used for emergency boots in aging systems lacking support for other bootable media and for BIOS updates, since most BIOS and firmware programs can still be executed from bootable floppy disks . If BIOS updates fail or become corrupt, floppy drives can sometimes be used to perform

1547-470: A single 360 KB 5.25" drive and a 20 MB hard drive. An Iomega Bernoulli 10/10 removable cartridge drive was also offered as a factory option, as well as a "small expansion" sidecar hosting a hard drive for users who found themselves with no internal space left between floppies and expansion cards. After the 6300 Plus, AT&T announced that it was turning over both production and development of its PC products to Olivetti . In 1987, AT&T offered

1638-517: A single 64-bit wide bank); the expansion card also had its own monitor port built in allowing native dual-monitor support. CGA compatibility was necessarily limited to "RGB" modes, and "well behaved" software that only used the BIOS-preset modes and didn't attempt too much clever direct reprogramming of the CRTC registers (including setting of pseudo-text hack modes like 160×100 16 colours), as there

1729-505: A single hole in the rotating floppy disk medium line up. This mechanism is used to detect the angular start of each track, and whether or not the disk is rotating at the correct speed. Early 8‑inch and 5¼‑inch disks also had holes for each sector in the enclosed magnetic medium, in addition to the index hole, with the same radial distance from the center, for alignment with the same envelope hole. These were termed hard sectored disks. Later soft- sectored disks have only one index hole in

1820-447: A small circle of floppy magnetic material encased in hard plastic. Earlier types of floppy disks did not have this plastic case, which protects the magnetic material from abuse and damage. A sliding metal cover protects the delicate magnetic surface when the diskette is not in use and automatically opens when the diskette is inserted into the computer. The diskette has a square shape: there are apparently eight possible ways to insert it into

1911-411: A small oblong opening in both sides to allow the drive's heads to read and write data and a large hole in the center to allow the magnetic medium to spin by rotating it from its middle hole. Inside the cover are two layers of fabric with the magnetic medium sandwiched in the middle. The fabric is designed to reduce friction between the medium and the outer cover, and catch particles of debris abraded off

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2002-439: A thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined with a fabric that removes dust particles from the spinning disk. The three most popular (and commercially available) floppy disks are the 8-inch, 5¼-inch, and 3½-inch floppy disks. Floppy disks store digital data which can be read and written when the disk is inserted into a floppy disk drive ( FDD ) connected to or inside

2093-539: A true AT-based 286, their 6310 — a rebadge of Olivetti M28 . Equipped with a one- wait state 8 MHz processor, it was a pretty slow machine for its class, even slower than the IBM XT 286 . Simultask was also an option for the 6310. The later-released 6312 addressed the speed problem with a 12-MHz CPU. After the announcement of the 6310, in April 1987, AT&T announced price cuts across its 6300 PC product line, with

2184-475: Is a common source of disk corruption if a disk is changed and the drive (and hence the operating system) fails to notice. One of the chief usability problems of the floppy disk is its vulnerability; even inside a closed plastic housing, the disk medium is highly sensitive to dust, condensation and temperature extremes. As with all magnetic storage , it is vulnerable to magnetic fields. Blank disks have been distributed with an extensive set of warnings, cautioning

2275-456: Is correctly aligned. For a drive without the sensor, the mechanism attempts to move the head the maximum possible number of positions needed to reach track zero, knowing that once this motion is complete, the head will be positioned over track zero. Some drive mechanisms such as the Apple II 5¼-inch drive without a track zero sensor, produce characteristic mechanical noises when trying to move

2366-577: Is not a true portable, because it needs an external power source in all except the last version. Five versions exist: BYTE in 1989 listed the T3100/20 as among the "Distinction" winners of the BYTE Awards, citing its "amazingly clear" display and hard drive. Olivetti M24 The Olivetti M24 is a computer that was sold by Olivetti in 1983 using the Intel 8086 CPU . The system

2457-428: Is still used by software on user-interface elements related to saving files even though physical floppy disks are largely obsolete. Examples of such software include LibreOffice , Microsoft Paint , and WordPad . The 8-inch and 5¼-inch floppy disks contain a magnetically coated round plastic medium with a large circular hole in the center for a drive's spindle. The medium is contained in a square plastic cover that has

2548-476: The 6300 Plus that used a 6 MHz 286 microprocessor in the same case as the 6300. Prior to release, this machine had been referred to as the 8300 and codenamed "Safari 5" ( PC 7300 was "Safari 4"). On the hardware level, this machine was criticized by an InfoWorld reviewer for being incompatible with AT cards . On the other hand, AT&T sold a package of the 6300 Plus bundled with Simultask , which ran MS-DOS and UNIX System V simultaneously, at

2639-584: The PERSONA 1600 , built by LogAbax . The initial 1984 US version named AT&T 6300 came with either one or two 360 KB 5.25" floppy drives; a hard disk was not offered. In Europe, Olivetti launched a 10 MHz version: the Olivetti M24 SP , announced in November 1985, a contender for the title of "highest clocked 8086 computer" as its processor was the fastest grade of 8086-2, rated for

2730-551: The Type 1 Diskette in 1973, the industry continued to use the terms "floppy disk" or "floppy". In 1976, Shugart Associates introduced the 5¼-inch floppy disk drive. By 1978, there were more than ten manufacturers producing such drives. There were competing floppy disk formats , with hard- and soft-sector versions and encoding schemes such as differential Manchester encoding (DM), modified frequency modulation (MFM), M FM and group coded recording (GCR). The 5¼-inch format displaced

2821-398: The 1990s were non-networked, and floppy disks were the primary means to transfer data between computers, a method known informally as sneakernet . Unlike hard disks, floppy disks were handled and seen; even a novice user could identify a floppy disk. Because of these factors, a picture of a 3½-inch floppy disk became an interface metaphor for saving data. As of 2024 , the floppy disk symbol

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2912-469: The 21st century, as a form of skeuomorphic design . 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 data storage capacity and data transfer speed , such as USB flash drives , memory cards , optical discs , and storage available through local computer networks and cloud storage . The first commercial floppy disks, developed in

3003-449: The 6300 Plus discounted by 27-38%, while the original 6300 was discounted by 17-23% (depending on configuration). 6300s made in 1986-1987 have BIOS Version 1.43 which added proper support for 3.5" floppies and fixed a number of bugs. As with all contemporary systems, a BIOS upgrade required a physical chip replacement, which AT&T provided for $ 35. The M24 was designed to be highly compatible with IBM PC . One of its characteristics

3094-648: The 6300 Plus, described below) put it in the fourth place in terms of market share in the US. Olivetti's M24 did much better in Europe, where it became the market leader in 1986. The company produced almost half a million M24 machines that year, about 200 000 of which went to the United States. As it claimed the crown of most PC machines sold in Europe that year, Olivetti also became the third largest PC manufacturer worldwide. Olivetti would however be unable to repeat

3185-522: The 6300 so long as they were designed to work either specifically with the machine (for high speed 16-bit cards), or in an IBM PC compatible mode (necessarily 8-bit at 4.77 MHz). However, the original graphics card had to remain in place even if no longer in use, as it formed an essential part of the bridge connecting the expansion board to the motherboard, and although it featured DIP switch jumpers to select between MDA / Hercules , 40 and 80 column CGA, and expanded video options including its own (as per

3276-523: The 6300) instead of the latterly more common 9-pin serial transmission. A January 1985 review in InfoWorld declared it "a fair performer, better than the 8088-equipped IBM PC and PC XT and about equal to the 8086-based Compaq Deskpro ", and taking pricing into account concluded that it was "a good deal, but by no means perfect." The reviewer wondered how the "5 MHz" 8086 in the Compaq ran as fast as

3367-527: The 720 KB double density 3½-inch microfloppy disk on its Convertible laptop computer in 1986 and the 1.44 MB (1,474,560 bytes) high-density version with the IBM Personal System/2 (PS/2) line in 1987. These disk drives could be added to older PC models. In 1988, Y-E Data introduced a drive for 2.88 MB Double-Sided Extended-Density (DSED) diskettes which was used by IBM in its top-of-the-line PS/2 and some RS/6000 models and in

3458-548: The 8-inch one for most uses, and the hard-sectored disk format disappeared. The most common capacity of the 5¼-inch format in DOS-based PCs was 360 KB (368,640 bytes) for the Double-Sided Double-Density (DSDD) format using MFM encoding. In 1984, IBM introduced with its PC/AT the 1.2 MB (1,228,800 bytes) dual-sided 5¼-inch floppy disk, but it never became very popular. IBM started using

3549-516: The IBM motherboard settings), there was no "disable" switch. Instead, the (socketed) Motorola HD6845 CRTC main controller chip had to be removed, and replaced with a simple but remarkably expensive bridging circuit (or a user installed set of jumper wires to the correct half-dozen socket terminals) to bypass the necessary bus signals through the card untouched. Some plasma-screen and early LCD based portables from Compaq and other manufacturers also copied

3640-497: The M20 mode using the 24 MHz system master crystal to drive the pixel clock either directly or (320×200 and 8×16 40-character only) divided in two (in comparison, contemporary IBM displays ran at 15.8 to 21.9 kHz with 14.3 to 16.3 MHz dot clocks). Colour depth remained the standard fixed 4-colour CGA palettes in 320×200, and "monochrome" in all higher modes (any selectable RGB(I) foreground colour/one of 15 shades, with

3731-720: The M24 The keyboard used a proprietary 9-pin D-sub connector built into the system board and had the unconventional option of plugging a mouse into the keyboard via another 9-pin D-sub connector. The mouse could be configured to simulate the usage of the keyboard's arrow keys in DOS applications without mouse support, aided by the choice of a parallel quadrature encoding design (as per the Microsoft Bus Mouse , Amiga , and Atari ST mice, all of which can be modified to work with

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3822-481: The M24/6300's graphics hardware to make better use of early square-pixel 640×400 panels popular for Japanese and other non-IBM portables (still well suited to the basic CGA/EGA resolutions, but not so much EGA-high or MDA/EGA text, and unable to show MCGA /VGA-high or Hercules graphics without cropping or losing details) in an IBM Compatible hardware ecosystem that otherwise avoided the mode. However, it remained on

3913-620: The M240 (8086 at 10 MHz, which AT&T marketed in the USA as the 6300 WGS) while the M28 (and M28 SP) was succeeded by the M280 (80286 at 12 MHz). Olivetti also introduced an M380 series (both tower and desktop) using the 80386 processor. Floppy disk A floppy disk or floppy diskette (casually referred to as a floppy , a diskette , or a disk ) is a type of disk storage composed of

4004-636: The Olivetti M24 were only 42 000 in the first year, well below the planned production capacity of 200 000 . As a result, AT&T introduced the faster models with hard drive and a math co-processor in March. Still, after about one year on the market, AT&T had only claimed about 1% of the PC market, on par with that of TeleVideo and Columbia Data Products , but well below that of Compaq and Kaypro . By December 1986 however, AT&T's PC line (including

4095-473: The Sony design, introduced in 1983 by many manufacturers, was then rapidly adopted. By 1988, the 3½-inch was outselling the 5¼-inch. Generally, the term floppy disk persisted, even though later style floppy disks have a rigid case around an internal floppy disk. By the end of the 1980s, 5¼-inch disks had been superseded by 3½-inch disks. During this time, PCs frequently came equipped with drives of both sizes. By

4186-584: The United States' nuclear forces". The government planned to update some of the technology by the end of the 2017 fiscal year. Use in Japan's government ended in 2024. Windows 10 and Windows 11 no longer come with drivers for floppy disk drives (both internal and external). However, they will still support them with a separate device driver provided by Microsoft. The British Airways Boeing 747-400 fleet, up to its retirement in 2020, used 3½-inch floppy disks to load avionics software. Sony, who had been in

4277-867: The bad luck of launching just a few months before the IBM PC/AT, which introduced the entirely different 16-bit connector and signalling standard extension to the PC bus now known simply as "ISA", and so ended up featuring slots incompatible on all three fronts of physical configuration, complement and arrangement of signals, and data transfer rate, significantly restricting the number of compatible 16-bit cards produced for it. The M24/6300 had an unusual enhanced 32 KB CGA -compatible video card (Video Enhanced Adapter - EGC 2413) which, in addition to standard 200-line CGA graphics modes (automatically line doubled, transparent to software, with text modes also using 400 scanlines with higher quality 8×16 pixel fonts, or even 16×16 in 40-column mode with an expansion ROM ), also supported an additional 640×400 pixel graphics mode, as well as

4368-471: The case via the video card which, rather than occupying an ISA slot, has two female edge connectors and plugs onto the ends of both the motherboard and the backplane , doubling as a bridge between them. The M24 has seven 8-bit ISA slots, as were standard for its time, but a number of slots (exact figure seeming to vary between one and at least four across extant machines) have proprietary second connectors to accept Olivetti-specific 16-bit cards. The machine had

4459-409: The computer in finding and synchronizing with the data in each track. The later 3½-inch drives of the mid-1980s did not use sector index holes, but instead also used synchronization patterns. Most 3½-inch drives used a constant speed drive motor and contain the same number of sectors across all tracks. This is sometimes referred to as Constant Angular Velocity (CAV). In order to fit more data onto

4550-406: The corresponding sensor; this was mainly a hardware cost-saving measure. The core of the 3½-inch disk is the same as the other two disks, but the front has only a label and a small opening for reading and writing data, protected by the shutter—a spring-loaded metal or plastic cover, pushed to the side on entry into the drive. Rather than having a hole in the center, it has a metal hub which mates to

4641-399: The current is reversed the magnetization aligns in the opposite direction, encoding one bit of data. To read data, the magnetization of the particles in the media induce a tiny voltage in the head coil as they pass under it. This small signal is amplified and sent to the floppy disk controller , which converts the streams of pulses from the media into data, checks it for errors, and sends it to

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4732-399: The disk media, an action originally accomplished by a disk-load solenoid. Later drives held the heads out of contact until a front-panel lever was rotated (5¼-inch) or disk insertion was complete (3½-inch). To write data, current is sent through a coil in the head as the media rotates. The head's magnetic field aligns the magnetization of the particles directly below the head on the media. When

4823-442: The disk shell are not quite square: its width is slightly less than its depth, so that it is impossible to insert the disk into a drive slot sideways (i.e. rotated 90 degrees from the correct shutter-first orientation). A diagonal notch at top right ensures that the disk is inserted into the drive in the correct orientation—not upside down or label-end first—and an arrow at top left indicates direction of insertion. The drive usually has

4914-466: The disk to keep them from accumulating on the heads. The cover is usually a one-part sheet, double-folded with flaps glued or spot-welded together. A small notch on the side of the disk identifies whether it is writable, as detected by a mechanical switch or photoelectric sensor . In the 8-inch disk, the notch being covered or not present enables writing, while in the 5¼-inch disk, the notch being present and uncovered enables writing. Tape may be used over

5005-406: The eight ways one might try to insert the diskette, only one is correct, and only that one will fit. An excellent design. A spindle motor in the drive rotates the magnetic medium at a certain speed, while a stepper motor-operated mechanism moves the magnetic read/write heads radially along the surface of the disk. Both read and write operations require the media to be rotating and the head to contact

5096-692: The existing 3½-inch designs was the SuperDisk in the late 1990s, using very narrow data tracks and a high precision head guidance mechanism with a capacity of 120 MB and backward-compatibility with standard 3½-inch floppies; a format war briefly occurred between SuperDisk and other high-density floppy-disk products, although ultimately recordable CDs/DVDs, solid-state flash storage, and eventually cloud-based online storage would render all these removable disk formats obsolete. External USB -based floppy disk drives are still available, and many modern systems provide firmware support for booting from such drives. In

5187-559: The expansion board), was divided down from a 24.0 MHz master crystal, with the CPU timing in particular using an Intel 8284 clock generator , as per the IBM PC, to produce the 33% duty cycle pulse wave required by the 8086. The system was designed "split-level", with the motherboard screwed onto the underside of the computer case and connected to the ISA bus backplane in the top section of

5278-834: The feat in the subsequent years, and so 1986 represents the company's apogee in terms of PC market share. The 6300 was also supported by Unix-based operating systems particularly by Venix /86 Encore, released in September 1984, and by a version of Xenix adapted for the machine by the Santa Cruz Operation , and announced in June 1985. In response to IBM's launch of their PS/2 line, Olivetti revamped their product line in July 1987 to include 3.5" floppy drives (in 5.25-to-3.5" converted bays though) and also introduced new 80386 -based products. The M24 (and M24 SP) were succeeded by

5369-555: The flexibility of floppy disks combined with greater capacity, but remained niche due to costs. High-capacity backward compatible floppy technologies became popular for a while and were sold as an option or even included in standard PCs, but in the long run, their use was limited to professionals and enthusiasts. Flash-based USB thumb drives finally were a practical and popular replacement, that supported traditional file systems and all common usage scenarios of floppy disks. As opposed to other solutions, no new drive type or special software

5460-457: The floppy disk business since 1983, ended domestic sales of all six 3½-inch floppy disk models as of March 2011. This has been viewed by some as the end of the floppy disk. While production of new floppy disk media has ceased, sales and uses of this media from inventories is expected to continue until at least 2026. For more than two decades, the floppy disk was the primary external writable storage device used. Most computing environments before

5551-512: The general population, floppy disks were often used to store a computer's operating system (OS). Most home computers from that time have an elementary OS and BASIC stored in read-only memory (ROM), with the option of loading a more advanced OS from a floppy disk. By the early 1990s, the increasing software size meant large packages like Windows or Adobe Photoshop required a dozen disks or more. In 1996, there were an estimated five billion standard floppy disks in use. An attempt to enhance

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5642-431: The greater capacity, compatibility with existing CD-ROM drives, and—with the advent of re-writeable CDs and packet writing—a similar reusability as floppy disks. However, CD-R/RWs remained mostly an archival medium, not a medium for exchanging data or editing files on the medium itself, because there was no common standard for packet writing which allowed for small updates. Other formats, such as magneto-optical discs , had

5733-531: The hard drive-equipped version found it on par with the (6 MHz, 80286 equipped) IBM PC AT as far as processor performance was concerned, but with considerably slower I/O. The initial model of the AT&;T 6300 (no hard disk and only 360K floppy) had slow sales in 1984 with only 28 500 sold compared to 1.5 million IBM PCs. The sales were not much better in the first three months of 1985, with only 8500 sold in that time period. If fact, worldwide sales of

5824-407: The heads past the reference surface. This physical striking is responsible for the 5¼-inch drive clicking during the boot of an Apple II, and the loud rattles of its DOS and ProDOS when disk errors occurred and track zero synchronization was attempted. All 8-inch and some 5¼-inch drives used a mechanical method to locate sectors, known as either hard sectors or soft sectors , and is the purpose of

5915-450: The host computer system. A blank unformatted diskette has a coating of magnetic oxide with no magnetic order to the particles. During formatting, the magnetizations of the particles are aligned forming tracks, each broken up into sectors , enabling the controller to properly read and write data. The tracks are concentric rings around the center, with spaces between tracks where no data is written; gaps with padding bytes are provided between

6006-499: The late 1960s, were 8 inches (203.2 mm) in diameter; they became commercially available in 1971 as a component of IBM products and both drives and disks were then sold separately starting in 1972 by Memorex and others. These disks and associated drives were produced and improved upon by IBM and other companies such as Memorex, Shugart Associates , and Burroughs Corporation . The term "floppy disk" appeared in print as early as 1970, and although IBM announced its first media as

6097-541: The limitations of the 80286. The PC 6300 Plus shipped with MS-DOS in 1985 though, because its Unix System V distribution would not be ready until the end of March 1986. The 6300 Plus did not sell as well as the original 6300. Forrester Research estimated in December 1986 that AT&T's financial losses in PC market were about $ 600M for the year. In 1986, AT&T began offering 3.5" 720 KB floppies and 20 MB hard disks . The Xerox 6060 came standard with

6188-424: The machine, only one of which is correct. What happens if I do it wrong? I try inserting the disk sideways. Ah, the designer thought of that. A little study shows that the case really isn't square: it's rectangular, so you can't insert a longer side. I try backward. The diskette goes in only part of the way. Small protrusions, indentations, and cutouts prevent the diskette from being inserted backward or upside down: of

6279-399: The media. In some 5¼-inch drives, insertion of the disk compresses and locks an ejection spring which partially ejects the disk upon opening the catch or lever. This enables a smaller concave area for the thumb and fingers to grasp the disk during removal. Newer 5¼-inch drives and all 3½-inch drives automatically engage the spindle and heads when a disk is inserted, doing the opposite with

6370-400: The medium, and sector position is determined by the disk controller or low-level software from patterns marking the start of a sector. Generally, the same drives are used to read and write both types of disks, with only the disks and controllers differing. Some operating systems using soft sectors, such as Apple DOS , do not use the index hole, and the drives designed for such systems often lack

6461-493: The mid-1990s, 5¼-inch drives had virtually disappeared, as the 3½-inch disk became the predominant floppy disk. The advantages of the 3½-inch disk were its higher capacity, its smaller physical size, and its rigid case which provided better protection from dirt and other environmental risks. Floppy disks became commonplace during the 1980s and 1990s in their use with personal computers to distribute software, transfer data, and create backups . Before hard disks became affordable to

6552-485: The mid-1990s, mechanically incompatible higher-density floppy disks were introduced, like the Iomega Zip disk . Adoption was limited by the competition between proprietary formats and the need to buy expensive drives for computers where the disks would be used. In some cases, failure in market penetration was exacerbated by the release of higher-capacity versions of the drive and media being not backward-compatible with

6643-526: The notch to change the mode of the disk. Punch devices were sold to convert read-only 5¼" disks to writable ones, and also to enable writing on the unused side of single-sided disks for computers with single-sided drives. The latter worked because single- and double-sided disks typically contained essentially identical actual magnetic media, for manufacturing efficiency. Disks whose obverse and reverse sides were thus used separately in single-sided drives were known as flippy disks . Disk notching 5¼" floppies for PCs

6734-485: The old format, including a rigid case with a sliding metal (or later, sometimes plastic) shutter over the head slot, which helped protect the delicate magnetic medium from dust and damage, and a sliding write protection tab, which was far more convenient than the adhesive tabs used with earlier disks. The large market share of the well-established 5¼-inch format made it difficult for these diverse mutually-incompatible new formats to gain significant market share. A variant on

6825-492: The original drives, dividing the users between new and old adopters. Consumers were wary of making costly investments into unproven and rapidly changing technologies, so none of the technologies became the established standard. Apple introduced the iMac G3 in 1998 with a CD-ROM drive but no floppy drive; this made USB-connected floppy drives popular accessories, as the iMac came without any writable removable media device. Recordable CDs were touted as an alternative, because of

6916-409: The press of the eject button. On Apple Macintosh computers with built-in 3½-inch disk drives, the ejection button is replaced by software controlling an ejection motor which only does so when the operating system no longer needs to access the drive. The user could drag the image of the floppy drive to the trash can on the desktop to eject the disk. In the case of a power failure or drive malfunction,

7007-403: The read operation; other errors are permanent and the disk controller will signal a failure to the operating system if multiple attempts to read the data still fail. After a disk is inserted, a catch or lever at the front of the drive is manually lowered to prevent the disk from accidentally emerging, engage the spindle clamping hub, and in two-sided drives, engage the second read/write head with

7098-516: The same processor at 8 MHz in the AT&T machine; however, this appears to be a misunderstanding given that the Compaq was switchable between a guaranteed IBM PC-compatible 4.77 MHz and an enhanced-performance 7.16 MHz clock rate (respectively one-third and one-half of the same NTSC colourburst crystal used in the IBM, but not the Olivetti/AT&;T), and defaulted to the latter on boot, as detailed in other publications of

7189-651: The second-generation NeXTcube and NeXTstation ; however, this format had limited market success due to lack of standards and movement to 1.44 MB drives. Throughout the early 1980s, limits of the 5¼-inch format became clear. Originally designed to be more practical than the 8-inch format, it was becoming considered too large; as the quality of recording media grew, data could be stored in a smaller area. Several solutions were developed, with drives at 2-, 2½-, 3-, 3¼-, 3½- and 4-inches (and Sony 's 90 mm × 94 mm (3.54 in × 3.70 in) disk) offered by various companies. They all had several advantages over

7280-502: The sectors and at the end of the track to allow for slight speed variations in the disk drive, and to permit better interoperability with disk drives connected to other similar systems. Each sector of data has a header that identifies the sector location on the disk. A cyclic redundancy check (CRC) is written into the sector headers and at the end of the user data so that the disk controller can detect potential errors. Some errors are soft and can be resolved by automatically re-trying

7371-413: The small hole in the jacket, off to the side of the spindle hole. A light beam sensor detects when a punched hole in the disk is visible through the hole in the jacket. For a soft-sectored disk, there is only a single hole, which is used to locate the first sector of each track. Clock timing is then used to find the other sectors behind it, which requires precise speed regulation of the drive motor. For

7462-408: The spindle of the drive. Typical 3½-inch disk magnetic coating materials are: Two holes at the bottom left and right indicate whether the disk is write-protected and whether it is high-density; these holes are spaced as far apart as the holes in punched A4 paper, allowing write-protected high-density floppy disks to be clipped into international standard ( ISO 838 ) ring binders . The dimensions of

7553-608: The time, and endlessly misreported (including as "8 MHz", about as frequently as the miscalculated "7.14 MHz") ever since. The reason behind the M24/6300's failure to perform any better than equal with the 1/9th-slower Deskpro may be traceable, as hinted at in the InfoWorld review, to poorly optimised graphics routines in the BIOS, which would have a particularly noticeable effect in the high resolution 640x400 and extended colour modes. A November 1985 review in PC Magazine of

7644-442: The user not to expose it to dangerous conditions. Rough treatment or removing the disk from the drive while the magnetic media is still spinning is likely to cause damage to the disk, drive head, or stored data. On the other hand, the 3½‑inch floppy disk has been lauded for its mechanical usability by human–computer interaction expert Donald Norman : A simple example of a good design is the 3½-inch magnetic diskette for computers,

7735-511: The whole a poorly supported oddity, much like IBM's own PGC and most Super EGAs outside of their limited library of applications with direct driver support, and PC graphics on the whole did not exceed 640×350 in 16 colours or 720×348 in monochrome until the arrival of both the VGA standard, and Windows 3.0 which provided a simple one-driver-for-all-programs framework for future expansion cards to build on. Olivetti produced 2 official keyboards for

7826-409: Was generally only required where users wanted to overwrite original 5¼" disks of store-bought software, which somewhat commonly shipped with no notch present. Another LED/photo-transistor pair located near the center of the disk detects the index hole once per rotation in the magnetic disk. Detection occurs whenever the drive's sensor, the holes in the correctly inserted floppy's plastic envelope and

7917-468: Was little financial incentive to omit the device from a system. Subsequently, enabled by the widespread support for USB flash drives and BIOS boot, manufacturers and retailers progressively reduced the availability of floppy disk drives as standard equipment. In February 2003, Dell , one of the leading personal computer vendors, announced that floppy drives would no longer be pre-installed on Dell Dimension home computers, although they were still available as

8008-438: Was no composite video output available and although some basic register settings remained the same, others were necessarily very different because of the line doubling trickery (itself a type of CRTC hack) and altered scan rates, and Olivetti's protective "scrambler" chip that attempted to convert custom settings to the nearest safe equivalents could only go so far. In its turn, the machine's headline 640×400 graphics mode received

8099-443: Was required that impeded adoption, since all that was necessary was an already common USB port . By 2002, most manufacturers still provided floppy disk drives as standard equipment to meet user demand for file-transfer and an emergency boot device, as well as for the general secure feeling of having the familiar device. By this time, the retail cost of a floppy drive had fallen to around $ 20 (equivalent to $ 34 in 2023), so there

8190-626: Was sold in the United States under its original name by Docutel /Olivetti of Dallas. AT&T and Xerox bought rights to rebadge the system as the AT&;T PC 6300 and the Xerox 6060 series, respectively. (AT&T owned 25% of Olivetti around this time. ) The AT&T 6300, launched in June 1984, was AT&T's first attempt to compete in the PC compatible market. It was also available in France as

8281-468: Was the use of the more powerful 8.0 MHz Intel 8086 CPU rather than the 4.77 MHz Intel 8088 used in IBM 's own PC XT , configured for "maximum mode" that allowed direct installation of an 8087 math co-processor (also at 8 MHz) to the motherboard . The CPU clock, along with most others in the machine (other than the serial baud rate generator and an IBM-standard 14.3 MHz crystal used on

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