Misplaced Pages

SuperDrive

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
#262737

78-539: SuperDrive is the product name for a floppy disk drive and later an optical disc drive made and marketed by Apple Inc. The name was initially used for what Apple called their high-density floppy disk drive, and later for the internal CD and DVD drive integrated with Apple computers. Though Apple no longer manufactures computers that feature built-in SuperDrives, the name is still used when referring to Apple's external CD and DVD drive accessory (pictured). The term

156-756: 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

234-400: A "cs" model, differentiated largely by type of LCD technology used. While both models came with 11.3" color displays with 800 × 600 resolution, the pricier 1400c came equipped with an active matrix display and the 1400cs came with a less expensive passive matrix, dual-scan display. The optional 6× CD-ROM is implemented using a sleep-swappable module system similar to the one pioneered by

312-750: A SuperDrive connected to them will behave as an 800 KB drive. These two models can be upgraded via the M0244 upgrade kit (which replaces the IWM disk controller with the SWIM) and gain full use of the SuperDrive. All later models shipped with the SWIM. The first Macintosh model to include a SuperDrive floppy drive was the Macintosh IIx (1988). Every Macintosh and PowerBook introduced from 1988 to 1997 (with

390-443: 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

468-650: 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

624-474: 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

702-413: 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

780-420: 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

858-557: 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

SECTION 10

#1732771712263

936-468: 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

1014-505: 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

1092-709: A slot-based interface called the Apple II 3.5 Disk Controller Card for Apple IIe and II GS computers so they too could use 1.40 MB storage and read/write MS-DOS. The controller card as well as the external Superdrive were discontinued in June 1994. The SuperDrive cannot be used with the original four Mac models ( Macintosh 128K through Macintosh Plus ), as their disk controller (the IWM ) doesn't support high density. The next two models to be released ( Macintosh II & Macintosh SE (1987)) also shipped with that controller;

1170-447: 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

1248-411: 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

1326-607: A starting price of $ 2,499, it was the first new PowerBook after the controversial PowerBook 5300 . After the introduction of the more powerful PowerBook 3400c in February 1997, the 1400 took on the role of Apple's entry level notebook and remained there until its discontinuation in May 1998. Its successor, the PowerBook G3 Series (i.e. - "Wallstreet"/"Mainstreet"), would ultimately go on to replace and consolidate not only

1404-439: 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

1482-475: 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

1560-400: 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

1638-428: 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

SECTION 20

#1732771712263

1716-553: Is the last Macintosh to include a SuperDrive, while the Late 2011 was the last iMac model with the built in optical drive. Apple has sold a USB-connected external SuperDrive as an accessory since 2008 with the introduction of the MacBook Air. The drive has faced criticism and mixed customer reviews, with 410 reviews averaging two and a half stars before Apple's removal of customer reviews from their shopping website. Criticism includes

1794-553: Is used, and extraction of the disc is difficult, requiring tweezers, use of a card with double-sided sticky tape, or complete disassembly of it. The MacBook Air , released on January 29, 2008, is the first Macintosh to not include a SuperDrive after it became standard across the line. Apple began phasing SuperDrives out across the Macintosh line beginning on July 20, 2011. The updated second generation 13-inch MacBook Pro , released on June 11, 2012 and discontinued on October 27, 2016,

1872-466: The PowerBook G4 , the drive controller used in the 1400 is incompatible with ATA-6 hard drives. Compatibility issues could also arise with hard drives larger than 8.2 GB, resolvable by partitioning the boot drive to less than 8.2 GB or by using Mac OS 8.6 or later. Additionally, unlike all Apple notebooks to come after it, the 1400 would not boot from a CD by holding down the C key while starting

1950-551: 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

2028-494: The 1400 also included an internal expansion slot. Although few applications were ever developed to utilize it, Apple did release their own branded video card which included an increased amount of VRAM and an external video port. Other devices included a third-party video card, as well as a relatively rare Ethernet networking card. There are several well-known issues concerning the PowerBook 1400. Like all other PowerBooks prior to

2106-458: The 1400, but the 2400c and 3400c as well. Throughout its 18 months on the market, the PowerBook 1400 was available in a number of different configurations. It was originally released with a 117 MHz PowerPC 603e processor; a 133 MHz processor was added in July 1997, and the line topped out with a 166 MHz processor the following December. Each version was available as either a "c" or

2184-398: 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

2262-469: 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

2340-527: 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

2418-548: 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

SuperDrive - Misplaced Pages Continue

2496-399: The PowerBook 5300; other modules include a Zip drive and the standard 1.4 MB floppy (an 8× CD-ROM would eventually become standard on the 133 MHz model). A pioneering feature of the 1400 is the "BookCover" laptop skin which allows owners the opportunity to give their PowerBook a customized look. Every 1400 shipped with a gray cover, a clear cover, and six inserts; a ClarisWorks template

2574-473: 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

2652-508: The Trademark name FDHD (Floppy Disk High Density), the subsequently renamed SuperDrive was known primarily as an internally mounted floppy drive that was part of the Macintosh computer; however, an external version of the drive was manufactured that came in a Snow White -styled plastic case. While the external drive worked on both Apple's product lines, it was mainly intended for use on the Apple II series, for which Apple introduced in 1991

2730-647: 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

2808-563: The ability to write to these discs is disabled. Apple never offered a Blu-ray drive or supported playback of the format. DVD±R DL Dual Layer DVD did not come out until 2005 and was not supported on the SuperDrive until the release of early 2005 models of PowerMac G5 which came with updated SuperDrives which supported DL recording on DL media. Unlike tray-style disc holders which have an inner guide ring, slot-style drives will not work with MiniCD or MiniDVD discs (8 cm diameter instead of 12 cm) unless an 8 cm optical disc adapter

2886-409: 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

2964-406: 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

3042-399: 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

3120-399: 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

3198-442: 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

SuperDrive - Misplaced Pages Continue

3276-466: 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

3354-406: 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

3432-557: The exception of the PowerBook 100 , PowerBook Duo series, and PowerBook 2400c , which offered a proprietary external floppy drive as an option), had a built-in SuperDrive floppy drive. The last model to include one was the beige Power Macintosh G3 series, which was manufactured until January 1999. The PowerBook G3 1998 model (a.k.a. Wallstreet) had an optional floppy drive module. The PowerBook 190 series, PowerBook 5300 Series, PowerBook 3400c , and original PowerBook G3 shared

3510-692: 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

3588-555: 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

3666-457: 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

3744-512: 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

3822-431: 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

3900-407: 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

3978-450: 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

SECTION 50

#1732771712263

4056-411: The lack of support for Blu-ray or mini optical discs and malfunctions that make the drive inoperable, with no way to eject a stuck disc. On newer Mac computers, it also requires the additional purchase of a USB-C -to-USB-A adapter to connect. 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

4134-499: 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

4212-424: 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

4290-399: 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

4368-400: 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

4446-493: 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

4524-485: 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

4602-526: 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

4680-485: 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

4758-537: The optical drives built into its Macintosh models, which could read and write both DVDs and CDs . The early 2001 release of the Power Mac G4 was the first Macintosh to include a SuperDrive. SuperDrives featured 6–24x write speeds and supported the DVD±R , DVD±RW , CD-R , and CD-RW formats along with all normal read-only media. Some drive models used as SuperDrives are capable of reading DVD-RAM ; on these drives,

SECTION 60

#1732771712263

4836-492: 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

4914-531: The other PowerBooks. The end of the SuperDrive coincides with the demise of Old World ROM Macs; with the advent of the New World ROM machines, Apple stopped offering internal floppy drives on all models. The SuperDrive is not supported in Mac OS X , not even on the few Old World ROM machines that can officially run OS X. Once the use of floppy disks started declining, Apple reused the trademark to refer to

4992-409: 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,

5070-403: 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

5148-412: The same interchangeable floppy drive module as a standard feature. The drive as mounted on PowerBooks lacked the auto-inject feature of Apple's initial desktop SuperDrive implementation, requiring the user to manually insert the disk all the way into the drive. The feature was dropped throughout the lineup during 1993–94. The PowerBook 1400 series also had a floppy drive module, but was incompatible with

5226-651: 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

5304-502: 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

5382-413: 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

5460-408: 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

5538-500: The track length increases. While the original IBM 8-inch disk was actually so defined, the other sizes are defined in the metric system, their usual names being but rough approximations. PowerBook 1400 The PowerBook 1400 is a notebook computer that was designed and sold by Apple Computer, Inc. (now Apple Inc. ) from 1996 to 1998 as part of their PowerBook series of Macintosh computers. Introduced in October 1996 at

5616-442: 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,

5694-640: Was also capable of reading and writing MS-DOS formatted disks and FAT12 file formats, using PC Exchange or other software, unlike the 400 KB and 800 KB drives. This was made possible as the SuperDrive now utilitized the same MFM (Modified Frequency Modulation) encoding scheme used by the IBM PC , yet still retained backward compatibility with Apple's variable-speed zoned CAV scheme and group coded recording encoding format, so it could continue to read Macintosh MFS , HFS and Apple II ProDOS formats on 400/800 KB disks. Introduced in 1988 under

5772-567: Was also included as an "extra" on the system restore CD, from which users could design their own BookCover. The 1400 was easily upgradeable. System memory modules can be "piggy-backed" onto each other (another feature unique to the 1400), allowing the use of additional RAM. The CPU is located on a removable daughter card, which can be replaced with one containing a faster processor, including a number of commercially available cards with PowerPC G3 processors from vendors such as Sonnet Technologies, NewerTech, and Vimage. Aside from its two PC Card slots,

5850-466: Was first used by Apple Computer in 1988 to refer to their 1.44  MB 3.5 inch floppy drive . This replaced the older 800 KB floppy drive that had been standard in the Macintosh up to then, but remained compatible in that it could continue to read and write both 800 KB (double-sided) and 400 KB (single-sided) floppy disks, as well as the newer high-density floppies. This drive

5928-409: 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

6006-468: 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

6084-443: 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

#262737