1.
Magnetic tape data storage
–
Magnetic tape data storage is a system for storing digital information on magnetic tape using digital recording. Modern magnetic tape is most commonly packaged in cartridges and cassettes, the device that performs writing or reading of data is a tape drive. Autoloaders and tape libraries automate cartridge handling, for example, a common cassette-based format is Linear Tape-Open, which comes in a variety of densities and is manufactured by several companies. Sony announced in 2014 that they had developed a storage technology with the highest reported magnetic tape data density,148 Gbit/in². Initially, magnetic tape for storage was wound on 10. 5-inch reels. This de facto standard for computer systems persisted through the late 1980s. Tape cartridges and cassettes were available as early as the mid-1970s and were used with small computer systems. With the introduction of the IBM3480 cartridge in 1984, large computer systems started to move away from open reel tapes, magnetic tape was first used to record computer data in 1951 on the Eckert-Mauchly UNIVAC I. The UNISERVO drive recording medium was a metal strip of 0. 5-inch wide nickel-plated phosphor bronze. Recording density was 128 characters per inch on eight tracks at a speed of 100 in/s. Of the eight tracks, six were data, one was a parity track, making allowance for the empty space between tape blocks, the actual transfer rate was around 7,200 characters per second. A small reel of mylar tape provided separation from the metal tape, IBM computers from the 1950s used ferrous-oxide coated tape similar to that used in audio recording. IBMs technology soon became the de facto industry standard, magnetic tape dimensions were 0. 5-inch wide and wound on removable reels up to 10.5 inches in diameter. Different tape lengths were available with 1,200 feet and 2,400 feet on mil, during the 1980s, longer tape lengths such as 3,600 feet became available using a much thinner PET film. Most tape drives could support a maximum size of 10.5 inches. CDC used IBM compatible 1/2 inch magnetic tapes, but also offered a 1 inch wide variant, a so-called mini-reel was common for smaller data sets, such as for software distribution. These were 7-inch reels, often with no fixed length—the tape was sized to fit the amount of data recorded on it as a cost-saving measure. Early IBM tape drives, such as the IBM727 and IBM729, were mechanically sophisticated floor-standing drives that used vacuum columns to buffer long u-shaped loops of tape
2.
PDP-11
–
The PDP-11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation from 1970 into the 1990s, one of a succession of products in the PDP series. The PDP-11 had several innovative features, and was easier to program than its predecessors through the additional general-purpose registers. The PDP-11 replaced the PDP-8 in many applications, although both product lines lived in parallel for more than 10 years. In total, around 600,000 PDP-11s of all models were sold and its successor in the mid-range minicomputer niche was the 32-bit VAX-11, named as a nod to the PDP-11s popularity. The PDP-11 is considered by experts to be the most popular minicomputer ever. Design features of the PDP-11 influenced the design of most late-1970s computer systems including the Intel x86, design features of PDP-11 operating systems, as well as other operating systems from Digital Equipment, influenced the design of other operating systems such as CP/M and hence also MS-DOS. For a decade, the PDP-11 was the smallest system that could run Unix and it is commonly stated that the C programming language took advantage of several low-level PDP-11–dependent programming features, albeit not originally by design. In 1967–68, DEC engineers designed a 16-bit, word-addressed machine, management cancelled the project and some of the engineers later left DEC and produced it as the Data General Nova. A subsequent effort, code-named Desk Calculator, looked at a variety of options before choosing what became the 16-bit PDP-11, DECs previous PDP-8 and PDP-9 had 12- and 18-bit words, the PDP-11 family was announced in January 1970 and shipments began early that year. DEC sold over 170,000 PDP-11s in the 1970s, initially manufactured of small-scale transistor–transistor logic, a single-board large scale integration version of the processor was developed in 1975. A two-or-three-chip processor, the J-11 was developed in 1979, the last models of the PDP-11 line were the PDP-11/94 and -11/93 introduced in 1990. The PDP-11 processor architecture has an orthogonal instruction set. For example, instead of such as load and store. More complex instructions such as add likewise can have memory, register, input, most operands can apply any of eight addressing modes to eight registers. The addressing modes provide register, immediate, absolute, relative, deferred, and indexed addressing, use of relative addressing lets a machine-language program be position-independent. Early models of the PDP-11 had no dedicated bus for input/output, an input/output device determined the memory addresses to which it would respond, and specified its own interrupt vector and interrupt priority. DEC openly published the basic Unibus specifications, even offering prototyping bus interface circuit boards, the Unibus made the PDP-11 suitable for custom peripherals. Higher-performance members of the PDP-11 family, starting with the PDP-11/45 Unibus and 11/83 Q-bus systems, instead, memory was interfaced by dedicated circuitry and space in the CPU cabinet, while the Unibus continued to be used for I/O only
3.
Reel
–
A reel is an object around which lengths of another material are wound for storage. Generally a reel has a core and walls on the sides to retain the material wound around the core. In some cases the core is hollow, although other items may be mounted on it, the size of the core is dependent on several factors. A smaller core will obviously allow more material to be stored in a given space, however, there is a limit to how tightly the stored material can be wound without damaging it and this limits how small the core can be. Other issues affecting the core include, Mechanical strength of the core Acceptable turning speed any functional requirements of the core e. g. For a reel that must be mechanically turned the size of the grips that mount it on the mechanical turning device, the size of the mountings needed to support the core during unwinding. Anything mounted on the cores With material such as photographic film that is flat and long but is relatively wide, in cases where the material is more uniform in cross-section, the material may be safely wound around a reel that is wider than its width. In this case, several windings are needed to create a layer on the reel, most films have visible cues which mark the end of the reel. This allows projectionists running reel-to-reel to change over to the reel on the other projector. A so-called two-reeler would have run about 20–24 minutes since the short film shipped to a movie theater for exhibition may have had slightly less than 1,000 ft on it. Most modern projectionists use the term reel when referring to a 2, 000-foot two-reeler, as modern films are rarely shipped by single 1, a standard Hollywood movie averages about five 2000-foot reels in length. Had it not been standardized there would have many difficulties in the manufacture of the related equipment. A16 mm reel is 400 feet and it runs, at sound speed, approximately the same amount of time as a 1, 000-foot 35 mm reel. A split reel is a motion picture film reel in two halves that, when assembled, hold a specific length of motion picture film that has been wound on a plastic core. Using a split reel allows film to be shipped or handled in a lighter and smaller form than film would on a fixed reel, in silent film terminology, two films on one reel. Actors may submit a demo reel of their work to prospective employers, often in physical reel format
4.
Magnetic tape
–
Magnetic tape is a medium for magnetic recording, made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany, based on magnetic wire recording, devices that record and play back audio and video using magnetic tape are tape recorders and video tape recorders. A device that stores data on magnetic tape is a tape drive. Magnetic tape revolutionized broadcast and recording, when all radio was live, it allowed programming to be recorded. At a time when gramophone records were recorded in one take, it allowed recordings to be made in multiple parts, which were then mixed and edited with tolerable loss in quality. It was a key technology in computer development, allowing unparalleled amounts of data to be mechanically created, stored for long periods. Nowadays, other technologies can perform the functions of magnetic tape, in many cases, these technologies are replacing tape. Despite this, innovation in the technology continues, and Sony, over years, magnetic tape made in the 1970s and 1980s can suffer from a type of deterioration called sticky-shed syndrome. Caused by hydrolysis of the binder of the tape, it can render the tape unusable, the oxide side of a tape is the surface that can be magnetically manipulated by a tape head. This is the side that stores the information, the side is simply a substrate to hold the tape together. The name originates from the fact that the side of most tapes is made of an oxide of iron. Magnetic tape was invented for recording sound by Fritz Pfleumer in 1928 in Germany, based on the invention of magnetic wire recording by Oberlin Smith in 1888, pfleumers invention used a ferric oxide powder coating on a long strip of paper. This invention was developed by the German electronics company AEG, which manufactured the recording machines and BASF. In 1933, working for AEG, Eduard Schuller developed the ring-shaped tape head, previous head designs were needle-shaped and tended to shred the tape. An important discovery made in this period was the technique of AC biasing, due to the escalating political tensions, and the outbreak of World War II, these developments were largely kept secret. A wide variety of recorders and formats have developed since, most significantly reel-to-reel, the practice of recording and editing audio using magnetic tape rapidly established itself as an obvious improvement over previous methods. Many saw the potential of making the same improvements in recording television, television signals are similar to audio signals. A major difference is that video signals use more bandwidth than audio signals, existing audio tape recorders could not practically capture a video signal
5.
Tape transport
–
A tape transport is the collection of parts of a magnetic tape player or recorder that the actual tape passes through. Transport parts include the head, capstan, pinch roller, tape pins, the tape transport as a whole is called the transport mechanism. The capstan is a spindle used to move recording tape through the mechanism of a tape recorder. The capstan is always placed downstream from the tape heads, to maintain the required tension against the tape heads and other part of the tape transport, a small amount of drag is placed on the supply reel. Tape recorder capstans have a similar to nautical capstans, which however have no pinch rollers. The use of a capstan allows the tape to run at a precise, capstans are precision-machined spindles, and polished very smooth, any out-of-roundness or imperfections can cause uneven motion and an audible effect called flutter. The alternative to capstan drive, simply driving the tape takeup reel, dual capstans, where one is on each side of the heads, are claimed to provide even smoother tape travel across the heads and result in less variance in the recorded/playback signal. The pinch roller is a rubberized, free-spinning wheel typically used to press magnetic tape against a capstan shaft in order to create friction necessary to drive the tape along the magnetic heads. Most magnetic tape recorders use one capstan motor and one pinch roller located after the heads in the direction of the moving tape. However multiple pinch rollers may also be employed in association with one or more capstans, dual pinch rollers are also used in auto-reverse cassette decks to drive the tape in both directions as needed. In this case, only one pinch roller is pressed against its corresponding capstan at a time, a tension arm is a device used in magnetic tape recorders/reproducers to control the tension of the magnetic tape during machine operation. The recorders equipped with an arm can utilize more than one of them to control tape tension in different direction of winding or during different modes of tape operation. One of many US Patents pertaining to Tension arm Workbench Guide to Tape Recorder Servicing
6.
Fujifilm
–
Fujifilm Holdings Corporation, better known as Fujifilm or simply Fuji, stylized as FUJiFILM, is a Japanese multinational photography and imaging company headquartered in Tokyo. Fuji Photo Film Co. Ltd. was established in 1934 with the aim of being the first Japanese producer of photographic films, over the following 10 years, the company produced photographic films, motion-picture films and X-ray films. In the 1940s, Fuji Photo entered the optical glasses, lenses, after the Second World War, Fuji Photo diversified, penetrating the medical, printing, electronic imaging and magnetic materials fields. In 1962, Fuji Photo and U. K. -based Rank Xerox Limited launched Fuji Xerox Co. Ltd. through a joint venture, from the mid-1950s, Fuji Photo accelerated the establishment of overseas sales bases. In the 1980s, Fuji Photo expanded its production and other bases overseas, meanwhile, Fuji Photo developed digital technologies for its photo-related, medical and printing businesses. Like its rival Eastman Kodak which dominated in the US, Fuji Photo enjoyed a longtime near-monopoly on camera film in Japan, the complaint was lodged by the US with the World Trade Organization. On January 30,1998, the WTO announced a sweeping rejection of Kodaks complaints about the market in Japan. The new millennium witnessed the spread of digital technology in cameras. Demand for photographic films plunged in line with the popularity of digital cameras. In response, Fuji Photo implemented management reforms aimed at effecting drastic transformation of its business structures, while both film manufacturers recognized this fundamental change, Fuji Photo adapted to this shift much more successfully than Eastman Kodak. In September 19,2006, Fujifilm announced plans to establish a holding company, Fujifilm and Fuji Xerox would become subsidiaries of the holding company. A representative of the company reconfirmed its commitment to film, which accounts for 3% of sales, Fuji Xerox is a joint venture between Fujifilm and Xerox Corporation of North America. Fujifilm bought Sericol Ltd. a UK-based printing ink company specializing in screen, narrow web, velvia, one of the most saturated and fine-grained slide films, valued by nature and landscape photographers. Fortia, consumer slide film, featuring extremely vivid color rendering suitable for flower photography, Fuji Neopan Professional black & white negative film. As a side note, Neopan 400 and 1600 were designed to use the same developing times, ACROS and SS do not share this feature. This uses the Fuji G-mount lenses, to be released in 2017 The Clear Shot series of 35mm compact cameras Instax series of instant camera, wiki collection of bibliographic works on Fujifilm
7.
Sony
–
Sony Corporation is a Japanese multinational conglomerate corporation that is headquartered in Kōnan, Minato, Tokyo. Its diversified business includes consumer and professional electronics, gaming, entertainment, the company is one of the leading manufacturers of electronic products for the consumer and professional markets. Sony was ranked 116th on the 2015 list of Fortune Global 500 and these make Sony one of the most comprehensive entertainment companies in the world. The group consists of Sony Corporation, Sony Pictures Entertainment, Sony Interactive Entertainment, Sony Music Entertainment, Sony Financial Holdings and others. Sony is among the Semiconductor sales leaders by year and as of 2013, the companys current slogan is BE MOVED. Their former slogans were make. believe, like. no. other, Sony has a weak tie to the SMFG keiretsu, the successor to the Mitsui keiretsu. Sony began in the wake of World War II, in 1946, Masaru Ibuka started an electronics shop in a department store building in Tokyo. The company had $530 in capital and a total of eight employees, in the following year he was joined by his colleague, Akio Morita, and they founded a company called Tokyo Tsushin Kogyo 東京通信工業. The company built Japans first tape recorder, called the Type-G, in 1958 the company changed its name to Sony. When Tokyo Tsushin Kogyo was looking for a name to use to market themselves, they strongly considered using their initials. The primary reason they did not is that the railway company Tokyo Kyuko was known as TTK, the company occasionally used the acronym Totsuko in Japan, but during his visit to the United States, Morita discovered that Americans had trouble pronouncing that name. Another early name that was tried out for a while was Tokyo Teletech until Akio Morita discovered that there was an American company already using Teletech as a brand name, the name Sony was chosen for the brand as a mix of two words. One was the Latin word sonus, which is the root of sonic and sound, and the other was sonny, a common slang term used in 1950s America to call a boy. In the 1950s Japan sonny boys, was a word into Japanese which connoted smart and presentable young men. The first Sony-branded product, the TR-55 transistor radio, appeared in 1955, at the time of the change, it was extremely unusual for a Japanese company to use Roman letters to spell its name instead of writing it in kanji. The move was not without opposition, TTKs principal bank at the time and they pushed for a name such as Sony Electronic Industries, or Sony Teletech. Akio Morita was firm, however, as he did not want the company tied to any particular industry. Eventually, both Ibuka and Mitsui Banks chairman gave their approval, according to Schiffer, Sonys TR-63 radio cracked open the U. S. market and launched the new industry of consumer microelectronics
8.
Linear Tape-Open
–
Hewlett Packard Enterprise, IBM and Quantum control the LTO Consortium, which directs development and manages licensing and certification of media and mechanism manufacturers. The standard form-factor of LTO technology goes by the name Ultrium, the seventh generation of LTO Ultrium was released in 2015 and can hold 6.0 TB in a cartridge of the same size. Upon introduction, LTO Ultrium rapidly defined the super tape market segment and has consistently been the best-selling super tape format, LTO is widely used with small and large computer systems, especially for backup. Half-inch magnetic tape has been used for storage for more than 60 years. In the mid 1980s, IBM and DEC put this kind of tape into a single reel, although the physical tape was nominally the same size, the technologies and intended markets were significantly different and there was no compatibility between them. IBM called its format 3480 and designed it to meet the requirements of its mainframe products. DEC originally called theirs CompacTape, but later it was renamed DLT, in the late 1980s, Exabytes Data8 format, derived from Sonys dual-reel cartridge 8 mm video format, saw some popularity, especially with UNIX systems. Sony followed this success with their own now-discontinued 8 mm data format, by the late 1990s, Quantums DLT and Sonys AIT were the leading options for high-capacity tape storage for PC servers and UNIX systems. These technologies were tightly controlled by their owners, consequently, there was little competition between vendors and the prices were relatively high. To counter this, IBM, HP and Seagate formed the LTO Consortium, much of the technology is an extension of the work done by IBM at its Tucson lab during the previous 20 years. Around the time of the release of LTO-1, Seagates magnetic tape division was spun off as Seagate Removable Storage Solutions, later renamed Certance, despite the initial plans for two form-factors of LTO technology, only Ultrium was ever produced. In common usage, LTO generally refers to the Ultrium form factor, as of 2015, seven generations of LTO Ultrium technology have been made available and three more are planned. Between generations, there are strict compatibility rules that describe how, notes Data capacity and speed figures above are for uncompressed data. Most manufacturers list compressed capacities on their marketing material, capacities are often stated on tapes as double the actual value, they assume that data will be compressed with a 2,1 ratio. See Compression below and the table above, the units for data capacity and data transfer rates generally follow the decimal SI prefix convention and not the binary prefix convention. Minimum and maximum reading and writing speeds are drive-dependent, in contrast to other tape technologies, an Ultrium cartridge is rigidly defined by a particular generation of LTO technology and cannot be used in any other way. While Ultrium drives are also defined by a generation, they are required to have some level of compatibility with older generations of cartridges. The rules for compatibility between generations of drives and cartridges is as follows, An Ultrium drive can read data from a cartridge in its own generation and the two prior generations
9.
Serial Attached SCSI
–
Serial Attached SCSI is a point-to-point serial protocol that moves data to and from computer storage devices such as hard drives and tape drives. SAS replaces the older Parallel SCSI bus technology that first appeared in the mid-1980s, SAS, like its predecessor, uses the standard SCSI command set. SAS offers optional compatibility with SATA, versions 2 and later and this allows for SATA drives to be connected to most SAS backplanes or controllers. The reverse, connecting SAS drives to SATA backplanes, is not possible, the T10 technical committee of the International Committee for Information Technology Standards develops and maintains the SAS protocol, the SCSI Trade Association promotes the technology. Initiators may be provided as a component on the motherboard or as an add-on host bus adapter. A target, a device containing logical units and target ports that receives device service and task management requests for processing, a target device could be a hard disk or a disk array system. A service delivery subsystem, the part of an I/O system that transmits information between an initiator and a target, typically cables connecting an initiator and target with or without expanders and backplanes constitute a service delivery subsystem. Expanders, devices that form part of a delivery subsystem. Expanders facilitate the connection of multiple SAS End devices to a single initiator port, sAS-1,3.0 Gbit/s, introduced in 2004 SAS-2,6.0 Gbit/s, available since February 2009 SAS-3,12.0 Gbit/s, available since March 2013 SAS-4,22. Each SAS port in a SAS domain has a SCSI port identifier that identifies the port uniquely within the SAS domain and it is assigned by the device manufacturer, like an Ethernet devices MAC address, and is typically worldwide unique as well. SAS devices use these port identifiers to address communications to each other, in addition, every SAS device has a SCSI device name, which identifies the SAS device uniquely in the world. One doesnt often see these names because the port identifiers tend to identify the device sufficiently. For comparison, in parallel SCSI, the SCSI ID is the port identifier, in Fibre Channel, the port identifier is a WWPN and the device name is a WWNN. In SAS, both SCSI port identifiers and SCSI device names take the form of a SAS address, which is a 64 bit value, people sometimes refer to a SCSI port identifier as the SAS address of a device, out of confusion. People sometimes call a SAS address a World Wide Name or WWN, for a SAS expander device, the SCSI port identifier and SCSI device name are the same SAS address. The SAS bus operates point-to-point while the SCSI bus is multidrop, each SAS device is connected by a dedicated link to the initiator, unless an expander is used. If one initiator is connected to one target, there is no opportunity for contention, with parallel SCSI, SAS has no termination issues and does not require terminator packs like parallel SCSI. SAS allows up to 65,535 devices through the use of expanders, SAS allows a higher transfer speed than most parallel SCSI standards
10.
Serial ATA
–
Serial ATA is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Although, a number of hot plug PATA offering were first invented and marketed by Core International beginning in the late 1980s for the Micro Channel architecture bus controllers, prior to SATAs introduction in 2003, the PATA was simply known as ATA. The AT Attachment name originated after the 1984 release of the IBM Personal Computer AT, the IBM AT was the first mass-produced computer where the hard disk was key to the systems performance. The IBM AT’s controller interface became a de facto industry interface for the inclusion of hard disks, SATA host adapters and devices communicate via a high-speed serial cable over two pairs of conductors. In contrast, parallel ATA uses a 16-bit wide data bus with many support and control signals. To ensure backward compatibility with legacy ATA software and applications, SATA uses the same basic ATA, SATA has replaced parallel ATA in consumer desktop and laptop computers, SATAs market share in the desktop PC market was 99% in 2008. A2008 standard, CFast to replace CompactFlash is based on SATA, Serial ATA industry compatibility specifications originate from the Serial ATA International Organization. The SATA-IO group collaboratively creates, reviews, ratifies, and publishes the interoperability specifications, the remainder of this article will try to use the terminology and specifications of SATA-IO. The term Hot Plug was a registered trademark issued by the USPTO and it was invented for computer components including PATA in the late 1980s by Hal Prewitt, founder of Core International. First patent details were disclosed in 1987 in USA and Europe related to development of the technology to connect host bus adapters to mass storage device however the filings were not completed. Core created and in 1990 marketed the worlds first disk controller, host adapter, disk drives, disk arrays, initial implementations were on the IBM PS/2 series and Micro Channel architecture bus controllers. The Serial ATA Spec includes logic for SATA device hotplugging, Devices and motherboards that meet the interoperability specification are capable of hot plugging. Unlike PATA, both SATA and eSATA support hot swapping by design, however, this feature requires proper support at the host, device, and operating-system levels. In general, all SATA devices support hot swapping, also most SATA host adapters support this command, advanced Host Controller Interface is an open host controller interface published and used by Intel, which has become a de facto standard. It allows the use of advanced features of SATA such as hotplug, if AHCI is not enabled by the motherboard and chipset, SATA controllers typically operate in IDE emulation mode, which does not allow access to device features not supported by the ATA standard. Even in those instances, a driver may have been created for a specific chipset. SATA revisions are often designated with a dash followed by roman numerals, e. g. SATA-III, to avoid confusion with the speed, revision 1. 0a was released on January 7,2003. First-generation SATA interfaces, now known as SATA1.5 Gbit/s, communicate at a rate of 1.5 Gbit/s, taking 8b/10b encoding overhead into account, they have an actual uncoded transfer rate of 1.2 Gbit/s
