Floppy disk memory 3.5. What are floppy disks: description, specifications and reviews

April 26, 2010, having lived her last 3.5-inch 24-year life. If someone doesn't remember, floppy disks are black square memory devices that once could be called flat, with 1.44 MB. Just one third of an mp3 song or several documents previously archived could fit. The Ministry of Defense is now buying them most actively in Russia: one of the experts interviewed told Life that "the archaic nature of floppy disks does not affect the trajectory of missiles." The American authorities, by the way, also buy floppies, the owner of the floppydisk.com store, Tom Persky, told us.

"I do not know of any company that currently produces floppy disks. It looks like the last floppy disk has already been issued "

For most users, Sony's announcement of the discontinuation of floppy disks passed unnoticed. Before that, manufacturers gradually stopped releasing equipment with floppy drives, these drives in Windows were designated by the letter "A" (under "B" were 5-inch floppy drives, so the traditional "C" remained - this is the system hDD). If you already knew this or are ready to clarify the previous proposal, then we are connected with the feeling of old age.

In 2015, the departments purchased floppy disks for at least 300 thousand rubles, from 2010 to May this year - for 2.3 million rubles. "At least" - because the search function for attached files (technical specifications) has not been working on the public procurement portal for three years, and representatives of the Lanit group refused to repair it. IN new version the portal, which was launched this year, has no function at all.

The Ministry of Defense needed most of all floppy disks - from January 2010 to May 2016, the War Ministry spent 563 thousand rubles on floppy disks, of which 80 thousand rubles were purchases of military enlistment offices.

Floppy disks are purchased for security reasons, to transfer information to the state secret protection service [structure of the Ministry of Defense], - a representative of one of the military enlistment offices told Life. - Mostly floppy disks are used to write secret maps.

What are these cards for and where they are used, the interlocutor did not explain, referring to the state secret. But it is known that floppy disks, for example, are used to control missiles. The US Audit Office reported in its report that the US military still uses 8-inch floppy disks to navigate missiles. The US nuclear forces are still dependent on "flops", they are planned to be removed from service in 2017.

According to a source close to the Ministry of Defense, "the actual archaism of floppy disks does not affect the trajectory of missiles." The department officially refused to comment on this topic.

For security reasons, floppy disks are also purchased by another law enforcement agency - the Ministry of Internal Affairs, one of the employees of the investigation department told us about this.

You must understand that many [police] departments do not have free access to the Internet due to secrecy. So we carry our criminal cases to the bosses for verification, downloading them to floppy disks, and they write the corrected files back to them and give them to us, '' says Alexey, adding that at least there is a reason to leave the office sometimes in a whole working day.

He noted that there are still many computers in the Ministry of Internal Affairs that are adapted to work with 3.5-inch floppy disks. And that the incompatibility of a number of government agencies with optical discs and flash drives is connected not only with secrecy - supposedly we are talking about saving.

It's good that in the XXI century you can buy a regular floppy disk. We don't get money for flash drives, they say it's expensive. They cost 150 rubles each, but you can buy a floppy disk on the wholesale market for 25-30 rubles. Well, if the markets are not there, then you have to go to large stationery or computer stores. There, a box with ten Hong Kong floppy disks costs 400 rubles. The check can be handed over to the accounting department, and in six months the money will be returned. They are just enough for a modest lunch in a cafe opposite the investigation department, - said the policeman.

But the Ministry of Internal Affairs did not make it into the top ten buyers - because the police, according to Alexei, themselves stock up on floppy disks. True, they will probably be needed soon - the Ministry includes the Federal Drug Control Service (FSKN), which purchased these media. The Federal Customs Service of the Russian Federation told us that diskettes are a necessary part of the operational activities of customs authorities:

"A 3.5-inch floppy disk, of course, looks wildly against the background of iPhones and mobile internet, but precisely because of huge amount loopholes through which classified information can leak, and old-fashioned floppy disks are needed that allow you to store and transfer information in your pocket, and not through a sieve called the Internet "

Director of information security system integrator Softline Oleg Shaburov (previously worked for the antivirus company Symantec) noted that he does not see any advantages in floppy disks and cannot be called an archival tool either - because of the vulnerability to magnetic radiation and moisture, the average storage period for them does not exceed 3-5 years. At the same time, Shaburov recalled that the first of the most common viruses were transferred to floppy.

"Well, unless the police and customs officers have a calculation that the attackers will not have a floppy drive - or that the virus will not fit on a floppy disk"

In addition to law enforcement agencies, among the largest buyers of floppy disks are also state universities, hospitals and clinics. From January 2010 to May this year, they spent 247 thousand rubles and 243 thousand rubles, respectively. Basically, universities and hospitals are forced to use floppy disks due to outdated technology. In March of this year, there was even an uproar over the fact that the Russian Academy of Sciences asked young scientists to apply for grants on diskettes, but the requirement was declared optional. The average age of RAS academicians is over 70 years.

The five leaders in the purchase of floppy disks also included the Pension Fund of Russia and city administrations. Over the past six years, they have spent 235 thousand rubles and 90 thousand rubles on diskettes, respectively. According to Alexander Burtsev, director of the company "Internet Partner", state institutions have become hostages of their infrastructure, and To the Pension Fund the multimillion-dollar works on modernization of equipment and software, regularly paid by him, do not help.

There are many floppy disk suppliers in Russia. Among them is Elena Cheprasova's Samara firm "Spetsstroisnab", which supplies computer and printing consumables.

These are regional divisions of the FSB, the Ministry of Internal Affairs, customs, courts. More often - these are contracts of thousands for 30 rubles, since government services, even the security forces, do not have free money: the crisis, - said the representative of Spetsstroisnab.

The company buys floppy disks from larger wholesalers that are gradually clearing out Asian warehouses. Tom Persky (sells over 200 thousand floppy disks a year) says that he does not often have orders from Russia, and he sells a little to the American departments - mostly floppy disks go to companies whose equipment works only "on flops." These are embroidery, stamping machines and other special machines.

Floppy disks are running out - their reserves will last for another five years. Tom Persky now makes more money not on floppy disks, but on a related service - he is ordered to quickly transfer data from large batches of floppy disks to modern media.

Floppy disks are a relic of the past for most computers in use today, but they have long served as the only source of information transfer between computers. These disks are floppy disks that are labeled "Disk 3.5 [A]" in Windows. Until now, this device can be found on old computers.

Floppy history

Floppy disks began to spread around when A. Shugart of IBM invented them. In the beginning, this device was huge - about 8 inches (over 20 cm). Synonyms for this name appeared almost immediately, such as " floppy disk"," floppy disk ". The last name appeared later, when floppies became smaller and reached 5.25". At that time their capacity was 360 kilobytes, which is difficult to imagine today, since today the smallest files are measured in megabytes.

By the mid 80s of the last century, the size of the floppy disk was 3.5 inches. This diskette lasted until the final transition to various discs and flash drives.

The capacity of the floppy disks could vary as the standard size was installed on an unformatted floppy disk and the formatting methods were different. In this regard, formats appeared that were incompatible with each other. The Macintosh company used floppy drives with a different principle of encoding for writing compared to IBM, which did not allow information on floppy disks to be transferred between different operating systems until Apple created floppy drives. SuperDrive, which worked in two modes.

Floppy disk device

Information is recorded on a thin plastic disk, which is protected from above by hard plastic, which has an open area on top, closed by a special shutter, usually metal. There was a dust-proof cloth under the hard plastic. The disc underneath is covered with a ferromagnetic material. By analogy with a hard drive, it is divided into tracks and sectors. The floppy disk has two surfaces that can be written to simultaneously (although there were also single-sided floppy disks, marked SS), since the magnetic heads are displaced relative to each other, and therefore, no interference is created during recording. The disc begins to move when the motor engages with the center of the disc, made of metal. Depending on where the recording is going, it makes 300-360 rpm.

The floppy disk had a stub that allowed or denied writing to the floppy disk.

Floppy disk formats

The most common floppy disk formats differed in the number of sides used, recording density, the number of sectors per track, and the size of the disks. The drive could have single (SD), double (DD), or quarter density (QD) (this density was used in clones with 5.25-inch floppy disks of 640 and 720 kilobytes), as well as high density (HD), which was different from the previous increased number of sectors, extended density (ED), in which the floppy disks had 36 sectors (standard - 18 sectors) and a volume of 2880 kilobytes, but there was a lot of negative reviews, and therefore they did not spread.

The 5.25 and 8 "floppy disks could have capacities ranging from 160 to 180 kilobytes. 8" floppies had only one side for recording. 5.25 "floppy disks for DD-drives already had a volume of 320-360 kilobytes, which is 3, A 5-inch floppy disk increased to 720 kilobytes (there was no SD and QD for a 3.5-inch diskette), for a 5.25 "QD, the volume was 640-720 kilobytes, for an HD 3.5" - 1440 kilobytes, 5.25 " - 1200 kilobytes.

There were deviations from these standards, for example, for the Iskra-1030 (1031) computers 320/360 kB floppy disks were used, which were actually SS / QDs, but their boot sector was marked as DS / DD, which led to the fact that the IBM PC drive could not read them, as well as the drive of these computers on the IBM PC floppy disk.

Floppy disk advantages

• The recording is carried out according to a simple algorithm.
• Low cost.
• Availability and versatility (in recent times, all computers were equipped with a floppy drive).
• The optimal volume for that time for transferring information between unconnected computers.
• Rewritability.

Disadvantages of floppies

• While volume was optimal for carrying text files, spreadsheets, it was small for photos, pictures, the capacity of a floppy disk (1.44 megabytes) was poorly suited for transfer softwareespecially when its size began to grow with terrifying rapidity.
• Constant squeak during recording.
• Slow write speed.
• Unreliability (if one sector is damaged, the entire disk could stop reading).
• Short service life (usually, after several uses, the disc was damaged largely due to the fact that the plastic surface did not protect it reliably).

These shortcomings led to the fact that most users left negative reviews about floppy disks, which gradually led to the creation of new media and the disappearance of floppy disks.

Disconnect the floppy disk

This is usually not necessary to safely remove the floppy. The floppy disk drive has a button with which the diskette was removed after the end of the noise it produced, which indicated the end of the recording.

In this case, the question of how to disable the floppy disk can be considered in relation to Computer BIOS... So, going into the BIOS and going to its Standart CMOS Features section, you can see the designation Drive A or Drive B depending on the type of floppy disks used, on the contrary, information about the capacity and size is indicated. If you need to disable it, you need to press the "+" button until the word None appears instead of the capacity and size, after which you need to press F10 to save the changes and reboot.

Floppy disk emulators

The appearance of these programs was due to the fact that floppy drives began to gradually disappear from computers, while some programs for writing files to a floppy disk required. Some accounting programs refused to save the file anywhere other than to a floppy disk.

One of the most common emulation programs was the Virtual Floppy Drive program, which provided full integration of a floppy drive, which was virtual, with the operating windows system before its Vista version, it was possible to create virtual floppies on which it was possible to place the necessary information, support was provided for virtual 3.5 "and 5.25" floppies with support for capacities from 160 KB to 2.88 MB. These floppy disks could be formatted, and also, which is important for that time, run in a console form.

Many such floppy disk emulators were released, but they all were characterized by approximately the same algorithm of action.

The disappearance of floppy disks

The edges of the casing covering the plastic disc were periodically bent, which caused the floppy disk to get stuck in the drive, the spring that was supposed to drive the casing into the initial state, could move, which led to the fact that the disk was not covered by the casing as it should have been. When a floppy fell to the floor, the disk would often fail. All this required some work.

But new times have come with new technologies. Recordable and rewritable CDs first appeared, then DVDs, etc., then flash media appeared, which had a lower cost per unit of capacity, greater durability, big amount overwrite cycle. All this led to the fact that in new computers the complete set of floppy drives was increasingly absent, and gradually floppy disks practically disappeared from our everyday life.

Cinquefoil Floppy Disc

With the almost complete disappearance of floppy disks in today's life, their name has not disappeared. Floppy Disc can be used as a low hedge, on rocky terraces, together with shrubs and trees, rock gardens and as a curb. It has bright pink semi-double flowers with yellowness in the middle on a bush up to 40 cm high. This shrub loves light, tolerates frosts and winters well.

Finally

Floppy disks were a portable data storage used in the absence of a network between computers and for some programs that automatically save data to a floppy disk. Later, floppy disk emulators began to be used for such programs. Floppy disks developed extremely slowly, their design and capacity were imperfect, which contributed to their disappearance. But the name "Floppy Disc" was left in the name of one of the decorative cinquefoil.

Evolution of the modern floppy disk

Most of the technologies used in personal computers were developed either after the advent of the PC, or specifically for them. One of the few exceptions is the floppy disk, aka floppy disk, aka floppy disk. Largely thanks to the floppy disk, the emergence of personal computers became possible, but it was thanks to personal computers that the floppy disk became so widespread. All of the following about capacities and formats applies to IBM compatible personal computers unless otherwise noted. This is due to their much wider distribution, especially in Russia. Therefore, below you will not find descriptions of exotic floppy disk layout formats - yes, fans of the Macintosh or Amiga platforms will not be offended by me.

The first sample floppy disk was developed by IBM in 1967. Thirty two years - for computer technology age is very respectable, but, apparently, "my old woman is still alive." Let's try to trace her life in development.

The time of birth of our heroine belongs to the initial period of the development of mini- and microcomputers. They required a storage medium different from the then bulky drives on magnetic and punched tapes, hard drives and punched cards (cardboard cards with rows of numbers and a complex pattern of machine-punched holes - something like brass discs for a mechanical piano. Approx. ed.). The period of infancy and childhood, that is, the development of technology, took four years, so the first commercial drives were offered by IBM in 1971 - the same year that Intel introduced the 4004 processor. We can say that the two events coincided by chance, since there was no preliminary intention to use a floppy drive on a future "Intel-compatible" personal computer. But this accident once again demonstrates the parallel development of various technologies that led to the appearance of the first personal computers.

The development of our heroine of the diskette in some way corresponds to the stages of maturation of homo sapiens, and in some ways it is completely opposite to it. A person gains intelligence with age, his capabilities increase; the same can be said for floppy disks, the capacity of which increases as technology improves. But the "growth" of floppy disks has a completely opposite tendency - with age it decreases.

Our heroine was born in the size (more precisely, in diameter) 8 inches (203.2 mm), which is not enough for a person, but for a medium with a capacity of a little more than 100 KB at that time it was just right. Named at birth the Flexible Disk, it quickly got a few slang names. For example, floppy disk "alias" comes from the English word flop ("flap your wings"). Indeed, the sound produced by waving a 20x20 cm envelope is similar to the noise produced by a bird of appropriate dimensions taking off. A diskette such a medium began to be called a little later, after the first reduction in size. This is perhaps the record for the number of names for the same technology.

Initially, a floppy disk consisted of two parts: a carrier and an envelope. The media was a circular plate with a central reinforced edge hole and one or more index holes cut from a wide and thick double-sided magnetic tape. The envelope was made of plastic, smooth on the outside and covered with pile on the inside, and had holes for a spindle that rotated the media, a slot for the heads and an optocoupler for reading the index.

At the very beginning, the division of floppy disks into sectors was rigid, that is, for each sector its own index hole was made. Subsequently, the number of index holes was reduced to one corresponding to the beginning of the track. Therefore, floppy disks like Hard Sectored (hard partitioning into sectors) and Soft Sectored (one index hole) coexisted for some time. Due to internal reserves, the volume of the media was increased from 100 to 256 KB, which remained the physical limit for standard 8-inch floppy disks. Until the end of the 70s, floppy disk drives were installed mainly in mini-, and then in microcomputers (the PC we are used to belongs to the class of microcomputers. - Approx. ed.). As a result, the volume of production of floppy drives was small, and therefore the prices for them went off scale for $ 1000.

The first commercial personal computer to use 8-inch floppy disks was the Apple II, shown as a prototype in 1976. However, just a few months earlier, Shugart had announced the release of a 5.25-inch floppy drive. reasonable price at $ 390. However, 8-inch floppy disks have been around for a long time, and the designs of the drives shine with variety. For example, in the Rainbow Personal Computer (DEC), to reduce cost, the two devices shared a common head drive so that only one diskette could be accessed at a time. By the way, to the question of longevity. 8-inch floppy disks are still in production: anyone who doesn't believe can check the Imation website (http://www.imation.com, formerly a division of 3M).

So, in 1976 there was the first reduction in the size of a floppy disk from 8 to 5.25 inches. Its volume briefly became equal to 180 KB, which was clearly not enough, so floppy disks soon appeared, recording on which was made from both sides. They received the name Double Density ("Double Density"), although it was not the density that was increased, but the volume. Such drives were installed in personal computer IBM PC, released in 1981.

As the volume of programs and data grew, it became clear that the capacity of a 360 KB floppy disk was clearly insufficient. Was developed new format and, accordingly, new floppy disks and drives. For the manufacture of floppy disks with a volume of 1.2 MB, improved magnetic materials were used, which made it possible, while reducing the track width by half and increasing the recording density, nevertheless, a satisfactory signal level from the read head was obtained. The doubling of the number of tracks (from 48 to 96) allowed for backward compatibility, that is, a 1.2 MB floppy drive could read a 360 KB floppy disk. Interestingly, there were no cutouts or holes on the floppy disk with which the drive could determine its type; this information was recorded in the table of contents.

However, having reached a decent (and practically maximum for this technology) density, the 5.25-inch floppy disk still suffered from "childhood diseases", that is, insufficient mechanical strength and the degree of protection of the carrier from external influences. Through the hole for the head block, the surface was easily dirty, especially if the disk was not stored in an envelope. The floppy disk was literally flexible: it could be folded into a tube and ... then thrown into the nearest trash can. The inscriptions on the sticker could only be done with a soft felt-tip pen, since a ballpoint pen or pencil pushed through the envelope material. So the time has come for the soft disk to acquire a hard shell.

In 1980, Sony demonstrated a new standard 3.5-inch floppy disk and drive. Now it has become difficult to call it flexible or floppy - "clapping". Solid hard plastic housing and no index hole provide mechanical protection to the media. The only remaining hole for the heads to access the media is covered by a spring-loaded metal shutter. To protect against accidental overwriting, there is not a sealed cut-out, like on a 5.25-inch floppy disk (try to find the necessary piece of black sticky paper at the right time!), But a movable flap, which is part of the body structure. The original capacity of the 3.5-inch floppy disk was 720KB (Double Density, DD), and then grew to 1.44MB (High Density, HD).

It was such a drive (and only one) that was installed in computers of the sensational and rather disastrous because of incompatible innovations of the IBM PS / 2 series of computers. Subsequently, this standard, due to obvious advantages, replaced 5.25-inch floppy disks. True, the more convenient Sony standard floppy disks in a hard plastic case were outperforming 5-inch drives for a long time in terms of price / capacity ratio, and the compatibility problem had been making itself felt for a long time: 3.5-inch drives could not be found everywhere.

The last evolutionary improvement of the floppy disk was undertaken by Toshiba in the late 1980s. By improving media technology and recording methods, the floppy disk capacity has been doubled to 2.88 MB. However, this format did not take root for a number of reasons. The high baud rate adopted in the drive of this format (more than 1 Mbit / s) was not supported by most of the previously released controllers and chipsets designed for the speed of 500 Kbps, that is, to use the new drive, it was necessary to purchase a corresponding card. The cost of such a floppy disk is high, at a few dollars, compared to about 50 cents for a regular 1.44MB floppy disk. And finally, the inertia of the huge mass of drives for 1.44 MB floppy disks, already available at that time, did not allow the market to swing towards 2.88 MB media - the use of a non-standard format could complicate exchange with the outside world.

Anatomy of a floppy disk

Like any other magnetic disk media, a floppy disk is divided into concentric tracks. The tracks, in turn, are divided into sectors. Moving the head to access different tracks is carried out using a special head positioning drive, which moves the magnetic head unit in the radial direction from one track to another. The various sectors within a track are accessed simply by rotating the media. It is interesting that the numbering of tracks starts from "0", and sectors - from "1", and this system was later transferred to hard drives.

The principle of recording information on a floppy disk is the same as in a tape recorder: there is a direct mechanical contact of the head with a magnetic layer applied to an artificial film - mylar. This determines the low read / write speed (the medium cannot move quickly relative to the head), low reliability and durability (after all, mechanical erasure and wear of the medium occur). Unlike a tape recorder, the recording is carried out without high-frequency bias - by reversing the magnetization of the media material to saturation.

As already noted, initially the marking of an 8-inch floppy disk into sectors was rigid, that is, the beginning of each sector corresponded to an index hole, the passage of which through an optocoupler caused an electrical impulse. This simplified the design of the controller (no need to track the beginning of each sector) and the drive (no need to maintain high rotation speed stability), but limited the increase in capacity due to internal reserves and reduced durability. Subsequently, thanks to the progress of microelectronics, the number of index holes was reduced to one corresponding to the track header, and the sector headers were recognized by the controller. There is no index hole in 3.5-inch floppy disks; synchronization is performed solely by reading headers.

At first, the positioning of the head was most often carried out using the "stepper motor-screw-nut" mechanism. The block of heads was mounted on a carriage moving along guides parallel to the radius of the floppy disk. In the carriage, there was a hole through which the screw passed, and on the hole there was a protrusion that entered the thread on the screw and played the role of the thread section of the nut. The stepper motor rotated the lead screw, moving the head assembly in the radial direction by means of the nut in one step per one track. On an 8-inch floppy disk, only such a mechanism could provide accurate positioning of the carriage with its long stroke (about 60 mm). After the appearance of smaller floppy disks (5.25 and 3.5 inches), another kinematic drive scheme was developed, which is still used today. It is based on a flexible elastic metal strip, one end attached to the carriage, and the other on a drum mounted on the stepper motor shaft. When the motor shaft (and the drum) is turned, the strip is wound or unwound, with its other end moving the carriage with the block of heads progressively along the radius of the floppy disk.

The general design principles of the classic diskette head assembly have undergone few changes. Their peculiarity lies in the presence of two tunnel erase heads located on the sides behind the recording / reproduction head. The role of these heads is to exclude the mutual influence of information recorded on adjacent tracks. To illustrate their work, you can use the following example: one person sprinkles a path with sand, and two following him sweep inward all the sand that has fallen over the edges of the path.

The drives, which should replace the classic floppy disk, use even more complex heads, which must interact with two different media, sometimes even based on different operating principles.

The diskette still has time to catch a cold at the funeral of its "killers"

So, the evolutionary development of the floppy disk ended due to the fact that technology had reached its limit. The period of revolutions has come, and, as in the political revolution, every revolutionary knows best what the "revolutionized" users need, and acts in accordance with it. The result is a variety of formats that differ from each other, so that compatibility between all these devices is really only ensured because they can work with a 1.44 MB floppy disk. The floppy disk killers line up, elbowing and interfering with each other. Let's list only the "loudest" names of these would-be killers:

• The LS-120 (Laser Servo) is the brainchild of Mitsubishi Electronics America and Winstation Systems, has a capacity of 120 MB and a maximum transfer rate of 4 MB / s (for SCSI interface). It can also be connected via the IDE interface. As with Sony's new 200MB HiFD drive, this drive uses different heads to handle 1.44MB floppy disk and high capacity media. A magnetic head with a "laser sight" is used to read / write 120 MB media. That is, the positioning of the head is carried out in the same way as it happens in CD-ROM drives, but only along the service tracks specially printed during the manufacture of the carrier, which cannot be rewritten. On the surface of an LS-120 floppy disk, 2,490 tracks per inch can fit, versus 135 tracks per inch for a conventional 1.44 MB floppy disk. An analogue of the LS-120 in principle of operation and volume, SuperDisk Drive was developed by Imation (formerly a division of 3M).
• The HiFD (High Capacity Floppy Disk) diskette and drive are jointly developed by Sony, TEAC, Alps and Fuji. At a spindle speed of 3600 rpm, a transfer rate of about 600 KB / s is provided (according to other sources, the Sony HiFD performance reaches 3.6 MB / s - testing by our laboratory will show. - Approx. ed.). The cartridge has a capacity of 200 MB.
• The UHC-31130 drive was invented by Mitsumi Electric and Swan Instruments.
• The Ultra High Density (UHD) drive from Caleb Technology Corp. has a capacity of 144 MB. According to the developers, this drive with an IDE interface provides a sevenfold increase in performance compared to a traditional floppy drive. Caleb UHD has a declared data transfer speed of 970 KB / s, costs about $ 70, and in the future it is planned to increase the storage capacity to 540 MB.
• Samsung's Pro-FD has a capacity of 123 MB and a transfer rate of 625 KB / s. The positioning uses exclusively magnetic technology with self-alignment.

The sheer abundance of technology and formats gathered at the floppy's "funeral" suggests that rumors of her death are greatly exaggerated. The reason for the wide popularity (maybe forced, since there is no replacement for it in the current situation and cannot be) of a floppy disk is precisely that it is possible not to check the presence of a certain type of drive in the company where the data is sent: you do not need to ask the secretary whether they have Zip or what magneto-optics they use. According to Disk / Trend, about 100 million 1.44MB floppy drives were sold last year.

The floppy drive not only did not die, but did not even weaken its positions - in terms of sales in pieces, it is 12 times stronger than all its competitors combined, including the Iomega Zip.

Therefore, my personal opinion is this: if anyone manages to bury a floppy disk, then not all these "gravediggers" - they repel each other more, seeking to take possession of the inheritance of the culprit of the event, than they are doing business. Moreover, they already have a competitor possessing the main qualities of a floppy disk, namely: complete and absolute compatibility and mass character. This refers to CD. As prices for rewritable discs and rewritable discs and related drives come down, they will become more widespread. Their main advantage is the "handicap" of hundreds of millions of already installed drives and full compatibility with each other.

A standard floppy drive has a data transfer rate of 62 KB / s and an average seek time of 84 ms. This, along with the ISA bus (to which 1.44 MB drives were connected until recently), is a serious limitation of their performance. Even very slow (by the standards of high-density drives) LS-120 class drives have a seek time of about 70 ms, and a data transfer rate of up to 565 KB / s.

ComputerPress 8 "1999

Diskette, floppy disk (GMD), floppy Disk, jarg. flop - portable magnetic data carrier. It is a plastic disk covered with a magnetic material and placed in a protective envelope.

Reading and writing information to a floppy disk is done by means of a floppy drive. Writing is done by the drive head sliding the spinning disc and magnetizing the surface.

Story

· 1971 - The first 200 mm (8 ″) floppy disk with a suitable disk drive was introduced by IBM. Usually the invention itself is attributed to Alan Sugart, who worked at IBM in the late 1960s.

1973 - Alan Shugert founds his own firm, Shugart Associates.

· 1976 - Alan Schugert develops the 5.25 ″ floppy disk.

1981 - Sony introduces a 3.5 ″ (90 mm) floppy disk. In the first version, the volume is 720 kilobytes (9 sectors). The later version has a volume of 1440 kilobytes or 1.40 megabytes (18 sectors). It is this type of floppy disk that becomes the standard (after IBM uses it in its IBM PC).

Later, the so-called ED floppy disks appeared (from the English. ExtendedDensity - "extended density"), which had a volume of 2880 kilobytes (36 sectors), which did not become widespread

Floppy disk design

The main components of a floppy disk are a magnetic disk that stores information and an envelope that performs protective function for the disk.

The envelope of 8- and 5.25-inch floppy disks was made from a material that allows it to bend easily enough, which became the reason to call them "flexible". 3.5-inch floppy disks were already produced in a hard plastic case, but the name has remained with them.

There are two main holes in the envelope: one in the center so that the spindle motor can grip and rotate the magnetic disk, the other is elongated from the center to the edge, and serves so that the heads can touch the surface of the disk. double-sided floppy disks have a hole on each side for this. For 3-inch floppy disks, the holes for the heads during transportation are closed by a shutter, which is opened by the mechanics of the disk drive when the disk is inserted.

The envelope also has a write-protect window or cutout. For 8- and 5-inch floppy disks, you need to glue the cutout for protection (for which a piece of paper with an adhesive layer was supplied with the floppy disk). On a 3-inch floppy disk, just move the slider in the window to open it.

Organizing information on a floppy disk

Physically, information on a diskette is a sequence of magnetized sections in different directions, the magnetization sequences are determined by error-resistant coding.

Data is written to a floppy disk in concentric tracks along the direction of rotation of the disk. By default, the side of a floppy disk holds 40 or 80 tracks. Usually it is possible to record 2-4 more tracks, but this is already determined by mechanical stops.

In this case, each track is divided into several sectors. Sector-by-sector writing provides random access in fairly small chunks. Some systems read and write the entire track, and then the partitioning into sectors may either not be performed or be purely logical. Typical sector sizes are 512B, although some systems use values \u200b\u200bbetween 128 and 1024B. 512-bit sectors typically fit on floppy 9 (double density), 15 (5-inch high-density floppies), or 18 (3-inch high-density floppies). density).

It should be noted that the actual capacity of the floppy disks depended on how they were formatted. Since, apart from the earliest models, virtually all floppy disks did not contain rigidly formed tracks, the road to experiments in the field of more effective use floppy disk was opened to system programmers. The result was the emergence of many incompatible diskette formats, even under the same operating systems. For example, for RT-11 and its versions adapted in the USSR, the number of incompatible floppy disk formats in circulation exceeded ten. (The most famous are MX, MY used in DCK).

Added to the confusion was the fact that Apple used floppy drives in its Macintosh computers that use a different magnetic tape encoding principle than the IBM PC. As a result, despite the use of identical floppy disks, transferring information between platforms on floppy disks was not possible until Apple introduced high-density SuperDrives that operated in both modes.

The “standard” formats of IBM PC floppy disks differed in disk size, number of sectors per track, number of sides used (SS stands for single-sided floppy, DS stands for double-sided), and the type (density) of the drive. The drive type was marked as SD - single density, DD - double density, QD - quadruple density (used in clones such as Robotron-1910 - 5.25 "floppy disk 720 K, Amstrad PC, PC Neuron - 5.25" floppy disk 640 K , HD - high density (differed from QD by an increased number of sectors), ED - extended density.

8-inch drives have long been included in the BIOS and were supported by MS-DOS, but there is no exact information about whether they were supplied to consumers (perhaps they were supplied to enterprises and organizations and were not sold to individuals).

In addition to the above format variations, there were a number of improvements and deviations from the standard floppy disk format.

The most famous ones - 320/360 KB floppy disks Iskra-1030 / Iskra-1031 - were actually SS / QD diskettes, but their boot sector was marked as DS / DD. As a result, the standard IBM PC disk drive could not read them without using special drivers (800.com), and the Iskra-1030 / Iskra-1031 disk drive, respectively, could not read the standard DS / DD diskettes from the IBM PC.

Special drivers-extenders BIOS 800, pu_1700 and a number of others allowed to format floppy disks with an arbitrary number of tracks and sectors. Since floppy drives usually supported from one to 4 additional tracks, and also allowed, depending on design features, to format 1-4 sectors per track more than the standard, these drivers provided the appearance of such non-standard formats as 800 KB (80 tracks, 10 sectors) 840 KB (84 tracks, 10 sectors), and so on. The maximum capacity consistently achieved with this method on 3.5 ″ HD drives was 1700 KB.

This technique was later used in Windows 98, as well as Microsoft's DMF floppy disk format, which expanded the floppy disk capacity to 1.68 MB by formatting floppy disks into 21 sectors in a similar IBM XDF format.

XDF was used on OS / 2 distributions, and DMF was used on various distributions software products from Microsoft.

The pu_1700 driver also allowed for offset and sector interleaved formatting - this accelerated sequential read / write operations, but was incompatible even with a standard number of sectors, sides, and tracks.

Finally, a fairly common modification of the 3.5 ″ floppy format is to format them at 1.2 MB (with a reduced number of sectors). This feature can usually be enabled in the BIOS modern computers... This use of 3.5 ″ is typical for Japan and South Africa. As a side effect, the activation of this bIOS settings usually reads floppy disks formatted with 800 type drivers.

Additional (non-standard) tracks and sectors sometimes contained copy protection data of proprietary floppy disks. Standard programs, such as the diskcopydid not transfer these sectors when copying.

The unformatted capacity of a 3.5 ″ floppy disk, determined by recording density and media area, is 2 MB.

The height of a 5.25 "floppy disk drive is 1 U. All CD drives, including Blu-ray, are the same width and height as a 5.25" drive (this does not apply to notebook drives).

The 5.25 ″ drive is nearly three times the height. This was sometimes used by the manufacturers of computer cases, where three devices placed in a square “basket” could be reoriented with it from horizontal to vertical arrangement.

Disappearing

One of the main problems with floppy disks was their fragility. The most vulnerable element of the floppy disk design was a tin or plastic casing that covered the floppy disk itself: its edges could be bent, which led to the floppy getting stuck in the floppy drive, the spring that returned the casing to its original position could be displaced, as a result, the floppy casing was separated from the casing and never returned to starting position. The plastic enclosure of the floppy disk itself did not provide sufficient protection against mechanical damage (for example, when a floppy disk falls on the floor), which disabled the magnetic media. Dust may have entered the crevices between the diskette case and the casing.

3.4. COMPUTER MEMORY

FLEXIBLE MAGNETIC DRIVES

Diskette - a portable magnetic storage medium used for multiple recording and storage of relatively small data. This type of media was especially common in the 1970s and late 1990s. The abbreviation is sometimes used instead of the term "floppy disk" GMD - "floppy disk" (respectively, the device for working with floppy disks is called NGMD - "floppy disk drive").

Typically, a floppy disk is a flexible plastic plate covered with a ferromagnetic layer, hence the English name "floppy disk". This plate is housed in a plastic housing that protects the magnetic layer from physical damage. The shell is flexible or rigid. Floppy disks are written and read using a special device - a floppy disk drive (floppy drive).

Floppy disks usually have a write protection feature, through which you can provide read-only access to data.

Floppy disks (8 ″; 5,25 ″ ; 3.5 ″ respectively)

Story

· 1971 - The first 200 mm (8 ″) floppy disk with a suitable disk drive was introduced by IBM. Usually the invention itself is attributed to Alan Sugart, who worked at IBM in the late 1960s.

· 1973 - Alan Shugert founds his own firm, Shugart Associates.

· 1976 - Alan Schugert develops the 5.25 ″ floppy disk.

· 1981 - Sony introduces a 3.5 ″ (90 mm) floppy disk to the market. In the first version, the volume is 720 kilobytes (9 sectors). The later version has a volume of 1440 kilobytes or 1.40 megabytes (18 sectors). It is this type of floppy disk that becomes the standard (after IBM uses it in its IBM PC).

Later, the so-called ED floppy disks appeared (from the English. Extended Density - "extended density"), which had a volume of 2880 kilobytes (36 sectors), which did not become widespread.

Formats

Chronology of floppy disk formats
Format	Year of origin	Volume in kilobytes
8 ″ double density
5.25 "double density
5.25 ″ Quad Density
5.25 "high density
3 ″ double density
3.5 "double density
3.5 "high density
3.5 ″ expanded density

It should be noted that the actual capacity of the floppy disks depended on how they were formatted. Since, apart from the earliest models, virtually all floppy disks did not contain hard-formed tracks, the path for experiments in the field of more efficient use of the floppy disk was open for system programmers. The result was the emergence of many incompatible floppy disk formats, even under the same operating systems. For example, for RT-11 and its versions adapted in the USSR, the number of incompatible floppy disk formats in circulation exceeded ten. (The most famous are MX, MY used in DCK).

Added to the confusion was the fact that Apple used floppy drives in its Macintosh computers that use a different magnetic tape encoding principle than the IBM PC. As a result, despite the use of identical floppy disks, transferring information between platforms on floppy disks was not possible until Apple introduced high-density SuperDrives that operated in both modes.

The “standard” formats of IBM PC floppy disks differed in disk size, number of sectors per track, number of sides used (SS stands for single-sided floppy, DS stands for double-sided), and the type (density) of the drive. The drive type was marked as SD - single density, DD - double density, QD - quadruple density (used in clones such as Robotron-1910 - 5.25 "floppy disk 720 K, Amstrad PC, PC Neuron - 5.25" floppy disk 640 K , HD - high density (differed from QD by an increased number of sectors), ED - extended density.

Working floppy densities and floppy capacities in kilobytes
Density	Inch

8-inch drives have long been included in the BIOS and were supported by MS-DOS, but there is no exact information about whether they were supplied to consumers (perhaps they were supplied to enterprises and organizations and were not sold to individuals).

In addition to the above format variations, there were a number of improvements and deviations from the standard floppy disk format. The most famous - 320/360 KB diskettes Iskra-1030 / Iskra-1031 - actually were SS / QD floppy disks, but their boot sector was marked as DS / DD. As a result, a standard IBM PC drive could not read them without using special drivers (800.com), and the Iskra-1030 / Iskra-1031 drive, respectively, could not read standard DS / DD diskettes from IBM PC.

Special drivers-extenders BIOS 800, pu_1700 and a number of others allowed to format floppy disks with an arbitrary number of tracks and sectors. Since floppy drives usually supported from one to 4 additional tracks, and also allowed, depending on design features, to format 1-4 sectors per track more than the standard, these drivers ensured the appearance of such non-standard formats as 800 KB (80 tracks, 10 sectors) 840 Kb (84 tracks, 10 sectors), etc. The maximum capacity, consistently achieved by this method, is 3.5″ HD drives was 1700 KB.

This technique was later used in Windows 98, as well as Microsoft's DMF floppy disk format, which expanded the floppy disk capacity to 1.68 MB by formatting the floppy disks into 21 sectors in the same IBM XDF format. XDF was used in OS / 2 distributions, and DMF was used in distributions of various software products from Microsoft.

Finally, a fairly common modification of the 3.5 ″ floppy format is to format them at 1.2 MB (with a reduced number of sectors). This feature can usually be enabled in the BIOS of modern computers. This use of 3.5 ″ is common in Japan and South Africa R. As a side effect, activating this BIOS setting will usually read floppies formatted with 800 type drivers.

Additional (non-standard) tracks and sectors sometimes contained copy protection data of proprietary floppy disks. Standard programs such as diskcopy did not transfer these sectors when copying.

The unformatted capacity of a 3.5 ″ floppy disk, determined by recording density and media area, is 2 MB.

The height of a 5.25 "floppy disk drive is 1 U. All CD drives, including Blu-ray, are the same width and height as a 5.25" drive (this does not apply to notebook drives).

The 5.25 ″ drive is nearly three times the height. This was sometimes used by the manufacturers of computer cases, where three devices placed in a square “basket” could be reoriented with it from horizontal to vertical arrangement.

Disappearing

One of the main problems with floppy disks was their fragility. The most vulnerable element of the floppy disk design was a tin or plastic casing that covered the floppy disk itself: its edges could bend, which led to the floppy disk getting stuck in the floppy drive, the spring that returned the casing to its original position could be displaced, as a result, the floppy disk casing was separated from the case and never returned to starting position. The plastic case of the floppy disk itself did not provide sufficient protection for the floppy disk from mechanical damage (for example, when a floppy disk fell on the floor), which rendered the magnetic medium out of order. Dust may have entered the crevices between the diskette case and the casing. And the floppy disk itself could be relatively easily demagnetized from the effects of magnetized metal surfaces, natural magnets, electromagnetic fields near high-frequency devices, which made the storage of information on floppy disks extremely unreliable.

The massive displacement of floppy disks from use began with the advent of rewritable CDs, and especially, flash-based media, which have a much lower unit cost, orders of magnitude greater capacity, higher actual number of rewriting cycles and durability, and higher data exchange rate.

An intermediate option between them and traditional floppy disks are magneto-optical media, Iomega Zip, Iomega Jaz and others. These removable media are sometimes also called floppy disks.

However, even in 2009, a floppy disk (usually 3.5 ") and an appropriate disk drive are required (if it is impossible to do this via the Internet directly from operating system) to "flash" the BIOS flash of many motherboards such as Gigabyte. They are also used to work with small files (usually with text files), to transfer these files from one computer to another. So we can say with complete confidence that floppy disks will be used for several more years, at least until the moment when the price of the cheapest flash drives will not be comparable to the prices for floppy disks (now their difference is ~ 10 times, but it is steadily decreasing) ...