At the very bottom would be the oldest and cheapest kind of memory tape drives.
|
|
Tape drives were invented over 60 years ago and were traditionally used for archiving tax documents and health care records.
|
|
The record of 201 gigabits per square inch on prototype sputtered magnetic tape is more than 20 times the areal density currently used in commercial tape drives.
|
|
From Tape Drives to Memory Orbs, the Data Formats of Star Wars Suck (Spoilers) (by Sarah Jeong) Rogue One: A Star Wars Story was supposed to be the first glorious spinoff from the main Star Wars franchise under Disney.
|
|
The problem isn't that qubits are going to escape their cryogenic prisons and go interfere with tape drives in the basement of some data center or HQ. The problem is what these quantum computers may be able to accomplish when they're finally put to use.
|
|
An interface standard for tape drives using the ATAPI (IDE) interface.
|
|
Some enterprise tape drives can quickly encrypt data. Symmetric streaming encryption algorithms can also provide high performance.
|
|
A powerful PC server loaded with disk and tape drives might require 1,000 volt-amperes or more.
|
|
The IBM 3590 is a series of tape drives and corresponding magnetic tape data storage media formats developed by IBM. The first drive, having the IBM product number 3590, was introduced in 1995 under the nickname Magstar. The 3590 series of tape drives and media are not compatible with the IBM 3592 line of drives that replaced it. They can store up to 60 GB of data (uncompressed). This family superseded the IBM 3480 Family of tape drives popular in 1980s and 1990s.
|
|
Some computer systems ran the operating system on tape drives such as DECtape. DECtape had fixed-size indexed blocks that could be rewritten without disturbing other blocks, so DECtape could be used like a slow disk drive. Data tape drives may use advanced data integrity techniques such as multilevel forward error correction, shingling, and linear serpentine layout for writing data to tape. Tape drives can be connected to a computer with SCSI, Fibre Channel, SATA, USB, FireWire, FICON, or other interfaces.
|
|
The tape drives were absolutely essential to any effort to read the original Lunar Orbiter data tapes. Dennis Wingo is president of the aerospace engineering company SkyCorp and a long-time worker in space and computing technologies. He knew he could muster the technical skills to tackle the management of renovating the tape drives, he could find contacts at NASA, and most importantly, he knew that the Moon was becoming a hot property again. Wingo said, "I knew the value of the tape drives and the tapes".
|
|
Like magnetic tape drives, floppy disk drives have physical limits on the spacing of flux reversals (also called transitions, represented by one-bits).
|
|
Valour User Manual © 1999 The product offered a wide variety of hierarchical backups, data streaming, alternating tape drives, and an ability to defragment minidisks.
|
|
Later documentation shows that a 13- or 19-inch color display was available. The color frame buffer had a resolution of 640×512 pixels, with 640×480 displayed on the monitor. The board could display 256 colors from a palette of 16 million. ½-inch 9-track reel-to-reel tape drives and QIC-02 ¼-inch cartridge tape drives were also added to the offering.
|
|
There may even be other lost data from the same era recorded using the same tape drives that could benefit from the efforts of the LOIRP team.
|
|
Because of their speed, reliability, durability and low media cost, the 3592 tape drives are still in high demand. A hallmark of the genre is interchangeability. Tapes recorded with one tape drive are generally readable on another drive, even if the tape drives were built by different manufacturers. Since TS1120 all drives include built-in encryption processing, with platform software (for example, z/OS Security Server) managing encryption keys.
|
|
Shoe-shining decreases the attainable data transfer rate, drive and tape life, and tape capacity. In early tape drives, non-continuous data transfer was normal and unavoidable. Computer processing power and available memory were usually insufficient to provide a constant stream, so tape drives were typically designed for start- stop operation. Early drives used very large spools, which necessarily had high inertia and did not start and stop moving easily.
|
|
That keypad was also used by programmers in the debugging process. There was no Operating System as we have come to know them in recent years; every program was completely self-contained, including the boot loader that initiated execution. All programs were loaded from punched cards; even on the SS II, with its tape drives, there was no ability to launch programs from those drives. The SS II, including two tape drives, weighed about .
|
|
There are technical advantages to backup-to-disk technology. One of the main advantages is the speed at which backups can be performed to the disk appliance. Backing up data to a backup-to-disk technology can be up to four times faster than traditional SCSI tape devices. While the new Serial Attached SCSI (SAS) connected tape drives are faster than the original tape drives, the disk appliance is still faster than most tape technologies.
|
|
Front half of LOIRP's facilities In February 2007, Wingo visited the four Ampex FR-900 tape drives for the first time in Evans's garage. Each drive was about tall, wide, as deep as a refrigerator, and weighed about . These were all coated with thick layers of dust and cobwebs. They were stored with a pallet of manuals and schematics for the tape drives, along with hard copies of data related to the lunar images.
|
|
LINC Tape II - Direct Access Mini-Computer Mass Storage System, Computer Operations Inc., Sept. 1974; 5 pages.Low Cost Tape Drives made for DEC, DG Gear, Computerworld, June 4, 1975; page 33.
|
|
The NORC had eight magnetic tape units which were similar to the tape drives on the IBM 701 system. The reels were 8 inches in diameter and somewhat similar in appearance to a metal 16mm film reel. Unlike the 701 series tape drives, there was no operator control panel on the face of the machine, instead there were buttons placed on the top front of the machines that were used to initiate tape loading, rewinding, unloading, etc.
|
|
0651 It could support up to 63 tape drives, punch tape input and output, as well as a Flexowriter. One connection could also be dedicated to sending data to another MOBIDIC system. The tape drives used one of the spare bits in the 40-bit word as a STOP indicator. Most of the 52 instructions were in the one-address format, collecting into an accumulator, but a small number (load, move, etc.) were in two-address format.
|
|
A tape drive provides sequential access storage, unlike a hard disk drive, which provides direct access storage. A disk drive can move to any position on the disk in a few milliseconds, but a tape drive must physically wind tape between reels to read any one particular piece of data. As a result, tape drives have very large average access times. However, tape drives can stream data very quickly off a tape when the required position has been reached.
|
|
A unique feature of the BIZMAC was the use of hundreds of permanently mounted tape drives. This meant that tape data could be accessed immediately without constant mounting and dismounting individual tapes.
|
|
1403 line printer opened, with 729 tape drives in the background. The IBM 1403 printer was introduced in October 1959 with the 1401 Data Processing System. The printer was a completely new development.
|
|
The SS II series included two enhancements the addition of 1,280 words of core memory and support for magnetic tape drives. The SS I had only the standard 5,000-word drum memory described in this article and no tape drives. Both variants included a card reader, a card punch, and the line printer described in this article. The only "console" was a 10-key adding machine-type keypad, from which the operator would enter the commands to boot the computer.
|
|
Many historic tape drives read and write variable-length data blocks, leaving significant wasted space on the tape between blocks (for the tape to physically start and stop moving). Some tape drives (and raw disks) support only fixed-length data blocks. Also, when writing to any medium such as a file system or network, it takes less time to write one large block than many small blocks. Therefore, the tar command writes data in records of many 512 B blocks.
|
|
Pertec Computer Corporation (PCC), formerly Peripheral Equipment Corporation (PEC), was a computer company based in Chatsworth, California which originally designed and manufactured peripherals such as floppy drives, tape drives, instrumentation control and other hardware for computers. Pertec's most successful products were hard disk drives and tape drives, which were sold as OEM to the top computer manufacturers, including IBM, Siemens and DEC. Pertec manufactured multiple models of seven and nine track half-inch tape drives with densities 800CPI (NRZI) and 1600CPI (PE) and phase-encoding formatters, which were used by a myriad of original equipment manufacturers as I/O devices for their product lines. In the 1970s, Pertec entered the computer industry through several acquisitions of computer producers and started manufacturing and marketing mostly minicomputers for data processing and pre-processing.
|
|
Meanwhile, Zin began testing the systems of the tape drives and making lists of devices to replace and refurbish. Parts for the drives were bought on eBay, online electronic parts stores, and other places.
|
|
This installation grew to be the largest Atlas, containing 48 kWords of 48-bit core memory and 32 tape drives. Time was made available to all UK universities. It was shut down in March 1974.
|
|
Tape drives are used with autoloaders and tape libraries which automatically load, unload, and store multiple tapes, increasing the volume of data which can be stored without manual intervention. In the early days of home computing, floppy and hard disk drives were very expensive. Many computers had an interface to store data via an audio tape recorder, typically on Compact Cassettes. Simple dedicated tape drives, such as the professional DECtape and the home ZX Microdrive and Rotronics Wafadrive, were also designed for inexpensive data storage.
|
|
The IBM 3570 is a series of tape drives and corresponding magnetic tape data storage media formats developed by IBM. The storage technology and media were introduced using the name Magstar MP, combining the IBM storage brand name Magstar with MP for MultiPurpose. The IBM product number 3570 was associated with the tape drives and libraries that used the Magstar MP media. The IBM 3570 technology was specifically produced for mid-range computer systems, and for the tape cartridges to be primarily stored in and handled by automated tape libraries.
|
|
Areal density is used to quantify and compare different types media used in data storage devices such as hard disk drives, optical disc drives and tape drives. The current unit of measure is typically gigabits per square inch.
|
|
One of the most compelling features of the AIT format is that many generations are both backwards and forwards compatible. This allows multiple generations of tape drives to both read and write to multiple generations of tape media.
|
|
At the same time, Burroughs was very much a competitor. Like IBM, Burroughs tried to supply a complete line of products for its customers, including Burroughs- designed printers, disk drives, tape drives, computer printing paper, and even typewriter ribbons.
|
|
7A's service entry was delayed due to the failure of the Army-supplied tape drives, but Sylvania replaced these with off-the-shelf commercial units and the system went operational in January 1962,Sokol, pg. 4 the first off-shore deployment.
|
|
Reel-to-reel tape was also used in early tape drives for data storage on mainframe computers, video tape recorder (VTR) machines, and high quality analog audio recorders, which have been in use from the early 1940s, up until the present.
|
|
The Administrative Module (AM) is a dual-processor mini main frame computer of the AT&T; 3B series, running UNIX-RTR. AM contains the hard drives and tape drives used to load and backup the central and peripheral processor software and translations. Disk drives were originally several 300 megabyte SMD multi- platter units in a separate frame. Now they consist of several redundant multi-gigabyte SCSI drives that each reside on a card. Tape drives were originally half inch open reel at 6250 bits per inch, which were replaced in the early 1990s with 4 mm Digital Audio Tape cassettes.
|
|
CRT memory, 702 CPU, 717 printer, operator's console, 757 printer control unit, 752 tape control unit, five 727 tape drives, 732 drum storage, five 727 tape drives, card reader, card punch, and reader/punch control units. The IBM 702 was IBM's response to the UNIVAC--the first mainframe computer using magnetic tapes. Because these machines had less computational power than the IBM 701 and ERA 1103, which were favored for scientific computing, the 702 was aimed at business computing. The 702 was announced September 25, 1953, and withdrawn October 1, 1954, but the first production model was not installed until July 1955.
|
|
HP Data Protector includes automated key management for software and Linear Tape-Open LTO-4 Encryption. Users have the choice of client-based encryption for data security, or they can use the encryption functionality in LTO-4 (and later generation) tape drives.
|
|
Twelve cartridges were released in addition to the built-in game Rocket Patrol. APF PeCos One was a computer system released in 1978. The name stood for "Personal Computing System." It came equipped with to built-in tape drives and a monitor.
|
|
Its products such as network interface controller cards are sold by distributors. The Chelsio Unified Storage Router product is also marketed by Dell, and was certified to work with tape drives from Quantum Corporation in 2011. Chelsio is involved with the OpenFabrics Alliance.
|
|
In recent decades, other technologies have been developed that can perform the functions of magnetic tape. In many cases, these technologies have replaced tape. Despite this, innovation in the technology continues, and Sony and IBM continue to produce new magnetic tape drives.
|
|
The first floor housed the network processors, switches, and utilized the first fibre-optic cables available in Canada. In addition, over 200 tape drives, a tape library of over one hundred and thirty thousand serial tape volumes on moveable shelves before disk-packs began to overtake tape data storage and the main console areas (the 'Dais') were on the first floor. To achieve the required efficiencies, CSG developed its own Pre-Scan software for the IBM MVS Operating System. This software facilitated tape drives being pre- allocated and tape files pre-mounted by tape operators as a job was read into the job scheduler.
|
|
RCA 501 Electronic Data Processing System The tape drives utilized an early version of data compression, whereby the "data on [the] tape [is] in proportion to the length of the data in each entry."All New Transistor RCA 501 Electronic Data Processing System It weighed about .
|
|
The same key is used to encrypt and decrypt data, and the algorithm can detect tampering with the data. Tape drives, tape libraries, and backup software can request and exchange encryption keys using either proprietary protocols, or an open standard like OASIS's Key Management Interoperability Protocol.
|
|
Originally NetVault Backup was intended to back up to physical tapes in tape drives. However, the product was soon extended to support backup to disk. For data deduplication, NetVault Backup supports Quest's DR appliance and NetVault SmartDisk. The Dell DR appliance is a hardware-based, inline deduplication storage product.
|
|
There were some attempts, such as the Bally Astrocade and APF-M1000 using tape drives, as well as the Disk System for the Nintendo Famicom, and the Nintendo 64DD fr the Nintedo 64, but these had limited applications, as magnetic media was more fragile and volatile than game cartridges.
|
|
He quit immediately. The first prototype for EDP ran on an IBM 360 Model 30 with IBM 2311 disk storage drives and two Tape Drives, and was programmed in COBOL. During seven years, it grew to support three- shift work-days and was used for thousands of companies’ payrolls.
|
|
The IIIC and later tapes used NRZI encoding to be compatible with the IBM 729 series tape drives which set the industry standard for data interchange. Ironically, IBM then later switched to phase encoding in its 1600-bit-per-inch tape generation because of its superior data reliability.
|
|
Linear serpentine The linear method arranges data in long parallel tracks that span the length of the tape. Multiple tape heads simultaneously write parallel tape tracks on a single medium. This method was used in early tape drives. It is the simplest recording method, but also has the lowest data density.
|
|
If a file is modified, Genera still keeps the old versions. Genera also provides access to, can read from and write to, other, local and remote, file systems including: NFS, FTP, HFS, CD-ROMs, tape drives. Genera supports netbooting. Genera provides a client for the Statice object database from Symbolics.
|
|
The time to access this point depends on how far away it is from the starting point. The case of ferrite-core memory is the opposite. Every core location is immediately accessible at any given time. Hard disks and modern linear serpentine tape drives do not precisely fit into either category.
|
|
The aggregate data rate for all drives reaches 58 TB/hour per module using T10000D drives, more with compression. Up to ten such modules can be connected side-by-side and automatically pass tapes between each other, forming a complex capable of storing over 925 PB of data and mounting 640 tape drives.
|
|
Available peripherals included teletypewriters, paper tape readers/punches, punched card readers/punches, line printers, magnetic tape drives, magnetic drums, fixed and removable magnetic disk drives, display terminals, communications controllers, Digigraphic display units, timers, etc. These interfaced to the processor using unbuffered interrupt-driven "A/Q" channels or buffered Direct Storage Access channels.
|
|
The documentation for the tape drives was substantially incomplete, which kept the team from understanding the right way to repair, maintain, and use the tape drives. The search for documentation has been extensive and usually disappointing, as it often turns out that retired or elderly engineers have just recently cleaned out their garages. Posting to a blog, Dennis Wingo said, "I cannot tell you how many times we have heard similar stories of recently tossed manuals over the last six months". At just the right moment the team heard from a friend of a friend that a mother lode of maintenance documentation stored on aperture cards (microfilm embedded in computer punch cards) had been saved by the retired head of Ampex field engineering.
|
|
High Performance Storage System (HPSS) is a flexible, scalable, policy-based Hierarchical Storage Management product developed by the HPSS Collaboration. It provides scalable hierarchical storage management (HSM), archive, and file system services using cluster, LAN and SAN technologies to aggregate the capacity and performance of many computers, disks, disk systems, tape drives and tape libraries.
|
|
Mass storage was provided by removable quarter-inch cartridge (QIC) magnetic tape drives that use standard DC300 cartridges to store 204 Kbytes. One drive was installed in the machine and a second (Model 5106) could be added in an attached box. The data format included several types and were written in 512 byte records.
|
|
TROS memory was used to store microcode for mainframe computers and intelligent controllers used to control sophisticated storage devices such as disk drives and tape drives. If there were a bug in the microcode it was possible to rework it by replacing one or more of the printed wiring sheets, thereby changing the contents of the microcode memory.
|
|
Iperius Backup is a virtual machine backup software. It can create full, incremental and differential backups (CBT/VDDK) of ESXi and ESXi Free virtual machines. The backup is agentless and the destination of VM backups can be LTO tape drives, NAS devices, cloud storage services like S3 or Google Drive, FTP servers and any mass storage device.
|
|
3592 Series tape Like the 3480 and 3592 formats, this tape format has half inch tape spooled onto 4-by-5-by-1 inch data cartridges containing a single reel. A takeup reel is embedded inside the tape drive. Because of their speed, reliability, durability and low media cost, the 3590 tape drives are still in high demand.
|
|
The DEC 4000 AXP has four fixed media mass storage compartments, each capable of holding one 5¼ inch or four 3½ inch devices. A single removable media mass storage compartment held the CD-ROM drives and tape drives. In addition to internal storage, an external storage cabinet could be attached via an external SCSI port to provide more storage.
|
|
The IBM 3592 is a series of tape drives and corresponding magnetic tape data storage media formats developed by IBM. The first drive, having the IBM product number 3592, was introduced under the nickname Jaguar. The next drive was the TS1120, also having the nickname Jaguar. , the latest and current drive is the TS1160 Gen 6.
|
|
Such particles are very small (generally below a micrometre in diameter). They are also very important in a lot of applications because they have a high coercivity. They are the main source of hardness in hard magnets, the carriers of magnetic storage in tape drives, and the best recorders of the ancient Earth's magnetic field (see paleomagnetism).
|
|
This was a major milestone that showed that the tapes and the tape drives were both good. Preliminary analysis showed that the image had "four times the dynamic range of the ... film image and up to twice the ultimate resolution". The NASA Exploration Systems Mission Directorate (ESMD) had sponsored the team so far with a small grant of $100,000.
|
|
In June 1964, CDC bought out Holley and partnered with NCR and ICL to form CPI in Rochester. In the early 1970s CPI also had a branch in Valley Forge, Pennsylvania. This division made punched card readers and 9-track magnetic tape drives for both parent companies (CDC and NCR). In 1978 CDC bought controlling interest of CPI.
|
|
Eddie Shoestring is a former computer expert who has resigned after suffering a nervous breakdown. In those days computers were large bulky machines with open reel tape drives creating considerable noise. In one episode Shoestring visits such a computer room and finds it mentally distressing. Following a period of convalescence, Shoestring has turned his hand to private detective work.
|
|
Fred Jordan founded Accuride in South Gate, California in 1962. and began as a small tool and die shop founded by Fred Jordan in 1962 in South Gate, California. The company produced slides for tape drives and copy machines.Accuride Web site, History Amid steady growth, the company moved to a larger facility in Santa Fe Springs four years later.
|
|
A motor is an actuator, converting electrical energy in to rotational mechanical energy. A motor requiring DC supply for operation is termed a DC motor. DC motors are widely used in control applications like robotics, tape drives, machines and many more. Separately excited DC motors are suitable for control applications because of separate field and armature circuit.
|
|
Rexon Business Machines, later Rexon, Inc., was a manufacturer of small business computer systems founded by Ben C. Wang in 1978 in Culver City, California. It also became a major manufacturer of tape drives and related products. At its height, it played a significant role in the development and sale of magnetic tape data storage products.
|
|
Oracle StorageTek SL8500 is an enterprise-class robotic tape library. Each library module starts with a capacity of 1448 tape cartridges, and expands in 1728 cartridge increments to a maximum capacity of 10888. It supports up to 64 tape drives and 4 or 8 independent robots in each library. Each tape drive installed in the SL8500 library has an independent data path.
|
|
Iperius Backup is a Hyper-V backup software. It can create hot backups of virtual machines running on the local server or on other servers reachable by the network. The backup is agentless and the destination of VM backups can be LTO tape drives, NAS devices, cloud storage services like S3 or Google Drive, FTP servers and any mass storage device.
|
|
File archiver and backup tools have been created to pack multiple files along with the related metadata into a single 'tape file'. Serpentine tape drives (e.g., QIC) can improve access time by switching to the appropriate track; tape partitions were used for directory information.Wangtek Corporation, OEM Manual, Series 5099ES/5125ES/5150ES SCSI Interface Streaming 1/4 Inch Tape Cartridge Drive, Rev D, 1991.
|
|
Commodore Datasette 1530 In the United States, the 1541 floppy disk drive was widespread. By contrast, in Europe, the C64 was often used with cassette tape drives (Datasette), which were much cheaper, but also much slower than floppy drives. The Datasette plugged into a proprietary edge connector on the Commodore 64's motherboard. Standard blank audio cassettes could be used in this drive.
|
|
COI LINC Tape II drive. Computer Operations Inc (COI) of Beltsville, Maryland offered a DECtape clone in the 1970s. Initially, COI offered LINC-tape drives for computers made by Data General, Hewlett-Packard and Varian, with only passing reference to its similarity to DECtape.Linc Tapes, Operating System Give Users I/O Paper Tape Option, Computerworld, Dec. 20, 1972; page 15.
|
|
The microprocessor, memory, serial interface card, and various optional functions were each on separate cards. This permitted easy field maintenance, upgrades, and reconfiguration. For example, more memory (providing larger scrollback capability) could be easily added, the serial interface could be changed from RS-232 to current loop, etc. The optional tape drives of the 2645 model were interfaced via another plug-in card.
|
|
In early 2007, Horzempa commented on the Lunar Orbiter tape recovery effort on a Web forum, NASASpaceflight.com. As a result, Dennis Wingo contacted Philip Horzempa through that forum. Horzempa put Wingo in contact with Nelson and Evans, and they invited Wingo to join the team. In addition to the tape drives mentioned above, Nelson had been able to obtain several tape heads.
|
|
An external QIC tape drive. Magnetic tape drives with capacities less than one megabyte were first used for data storage on mainframe computers in the 1950s. , capacities of 10 terabytes or higher of uncompressed data per cartridge were available. In early computer systems, magnetic tape served as the main storage medium because although the drives were expensive, the tapes were inexpensive.
|
|
The GM team later visited Douglas Engelbart's lab where they saw the first computer mouse, and based future projects on this device instead. All of the terminals were connected to a single controller, and in turn to the 7090 via its Channel C input. Channel A and B were used to control magnetic tape drives, and Channel D controlled the 1301 disk.
|
|
This was cpu relative performance. The A236 was #2100. Users of the 536x series of the System/36 had a few different routes to "migrate" to the A/36. One method was if you had compatible "tape" drives, you could basically do a "save all" of your libraries and data and restore them onto the A/36 from the S/36.
|
|
Large StorageTek Powderhorn tape library, showing tape cartridges with barcodes packed on shelves in the front and a robot arm moving in the back ADIC Scalar 100 tape library, showing a robot visible on the bottom with two IBM LTO2 tape drives behind it In computer storage, a tape library, sometimes called a tape silo, tape robot or tape jukebox, is a storage device that contains one or more tape drives, a number of slots to hold tape cartridges, a barcode reader to identify tape cartridges and an automated method for loading tapes (a robot). Additionally, the area where tapes that are NOT currently in a silo are stored is also called a tape library. Tape libraries can contain millions of tapes. One of the earliest examples was the IBM 3850 Mass Storage System (MSS), announced in 1974.
|
|
To what extent Strachey's third objective was reached, depends on how one views a price of £50,000 for Pegasus 1, which did not have magnetic tape drives, line printer or punched card input and output. The modular design with plug-in units of hardware did, however, make it very reliable by the standards of the day, and maintenance was "a doddle of a job".
|
|
Scalable Linear Recording is the name used by Tandberg Data for its line of QIC based tape drives. The earliest SLR drive, the SLR1, has a capacity of 250 MB, while the latest drive, the SLR140, has a capacity of 70 GB. The term SLR is now often used to refer to QIC tapes, as they are the only drives still manufactured that use them.
|
|
There were two entirely separate ground station designs which were developed independently. The smaller, more elegant, single silo design incorporated two redundant CDC 1604 computer systems, each equipped with dual cabinets containing four 200 bpi magnetic tape drives. The computers were used to pre-compute guidance and aiming control information. Results based on current weather and targeting information were downloaded into the missile prior to launch.
|
|
It was said to have a higher reliability than mechanical floppy disks or tape drives. Konami used a modified version of their new G400 BIOS for this project. The main CPU was a Motorola 68000 at 10 MHz. There was a separate Zilog Z80 for sound control, which drove two AY-3-8910s, a custom Konami SCC (K005289), and a Sanyo VLM5030 speech synthesizer.
|
|
ESCON cable with connectors ESCON (Enterprise Systems Connection) is a data connection created by IBM, and is commonly used to connect their mainframe computers to peripheral devices such as disk storage and tape drives. ESCON is an optical fiber, half-duplex, serial interface. It originally operated at a rate of 10 Mbyte/s, which was later increased to 17Mbyte/s. The current maximum distance is 43 kilometers.
|
|
For magnetic tape drives, azimuth refers to the angle between the tape head(s) and tape. In sound localization experiments and literature, the azimuth refers to the angle the sound source makes compared to the imaginary straight line that is drawn from within the head through the area between the eyes. An azimuth thruster in shipbuilding is a propeller that can be rotated horizontally.
|
|
Windows Backup does not support tape drives. It also does not support backing up to or restoring from a subfolder of a disk; instead, it creates subfolders of its own. Backup and Restore can only make a system image of disks with NTFS file system. If the system image is to be saved on a USB flash drive, it must be formatted with NTFS file system.
|
|
NPML technology were first introduced into IBM’s line of HDD products in the late 1990s. Eventually, noise-predictive detection became a de facto standard and in its various instantiations became the core technology of the read channel module in HDD systems. In 2010, NPML was introduced into IBM’s Linear Tape Open (LTO) tape drive products and in 2011 in IBM’s enterprise-class tape drives.
|
|
IBM 2311 disk drive DOS/360 required a System/360 CPU (model 25 and above) with the standard instruction set (decimal and floating-point instruction sets optional). The minimum memory requirement was 16 KB; storage protection was required only if multiprogramming was used. A 1052 Model 7DOS/360 on a S/370 used a 3210 or a 3215 rather than a 1052-7 printer-keyboard, either a selector or multiplexor channel, and at least one disk drive was required — initially a 2311 holding 7.25 MB. A card reader, card punch and line printer were usually included, but magnetic tape drives could be substituted. A typical configuration might consist of a S/360 model 30 with 32KB memory and the decimal instruction set, an IBM 2540 card reader/card punch, an IBM 1403 printer, two or three IBM 2311 disks, two IBM 2415 magnetic tape drives, and the 1052-7 console.
|
|
One of the FR-900 tape drives In a completed and working magnetic tape drive system, the tape-drive heads apply a very specific magnetic field to the tape; the tape then induces a change in electric current, which is captured. The data from the Lunar Orbiter tapes is then run through a demodulator, and through an analog-to-digital converter so that it can be fed into a computer for digital processing. Each image is divided up into strips on the tape, so the computer is used to bring the strips together to create a whole image. Before even beginning the project, the team evaluated the risks and determined that there were two: one was that the tapes had deteriorated to the point where they could not be read; the second was that the tape drives would not be able to read the tapes.
|
|
HP Data Protector offers data deduplication capabilities with the ability to compare blocks of data being written to a backup device with data blocks previously stored on the device. For data deduplication, HP Data Protector allows any disk-based data storage to be the target storage. Tape drives cannot be used as deduplication targets because of their sequential nature opposed to the block-oriented nature of disk-devices.
|
|
The client software is installed on each machine to be protected. The NetVault WebUI enables centralized administration of a NetVault Backup Server from any browser. NetVault supports tape drives, tape libraries, and other backup devices attached to the central server itself, or to a protected machine located anywhere on the network enabling LAN-free backups. Additionally, devices can be controlled through NDMP if they are attached to a supported filer.
|
|
Barium Ferrite is used in tape drives and floppy disks. Barium ferrite is used in applications such as recording media, permanent magnets, and magnetic stripe cards (credit cards, hotel keys, ID cards). Due to the stability of the material, it is able to be greatly reduced in size, making the packing density much greater. Earlier media devices utilized doped acicular oxide materials to yield the coercivity values necessary to record.
|
|
She decided that the tapes should be preserved. She recalled, "I could not morally get rid of this stuff". Within a few years, Nancy Evans and a few colleagues were able to start a small project with funding from NASA. They managed to find four rare Ampex FR-900 tape drives — highly specialized drives that had only been used by government agencies such as the FAA, USAF, and NASA.
|
|
All Dorado servers support TLS levels 1.0 through 1.2, as well as SSLv3, but SSL is disabled by default because of vulnerabilities in the protocol. Both CPComm and Cipher API use the encryption services of CryptoLib, a FIPS-certified software encryption module. The AES and Triple DES algorithms are among the algorithms implemented in CryptoLib. OS 2200 also supports encrypting tape drives, which provide encryption for archive data.
|
|
These drives are often referred to as tape streamers. The tape was stopped only when the buffer contained no data to be written, or when it was full of data during reading. As faster tape drives became available, despite being buffered, the drives started to suffer from the shoe-shining sequence of stop, rewind, start. Most recently, drives no longer operate at a single fixed linear speed, but have several speeds.
|
|
The milestones of the project were developed to test these risks as soon as possible with the least amount of money spent. Once the project started in earnest in July 2008, results came quickly. In only a couple of weeks, the first tape drive had been powered up, although it was clear that many parts still needed to be replaced. Another week of cleaning and testing revealed that among the four drives and batches of spare parts there were enough good power supplies to run one of the tape drives, and there was at least one working head for the drive. The head is the mechanism that touches the tape and reads and writes data, so it is absolutely critical; in the case of the Ampex FR-900 tape drives, the heads were not manufactured after 1974, cannot be replaced, and can only be refurbished at great expense by a single small company.
|
|
Until the advent of AIT, Exabyte were the sole vendor of 8 mm format tape drives. The company was formed with the aim of taking the 8 mm video format and making it suitable for data storage. They did so by building a reliable mechanism and data format that used the common 8 mm helical scan video tape technology that was available then. Exabyte's first 8 mm tape drive was made available in 1987.
|
|
Iperius Backup supports any tape drive. It allows users to save files to DAT, DLT, SDLT, LTO 1/2/3/4 - LTO 5, LTO 6/7/8 devices. It supports data compression and encryption, and parallel backups to multiple tape drives at the same time. Although the tape backup works well, the tape backup processes do not provide a lot of warning messages (ie "you're about to overwrite a tape. Yes/No").
|
|
Most tape drives now include some kind of lossless data compression. There are several algorithms which provide similar results: LZ (most), IDRC (Exabyte), ALDC (IBM, QIC) and DLZ1 (DLT). Embedded in tape drive hardware, these compress a relatively small buffer of data at a time, so cannot achieve extremely high compression even of highly redundant data. A ratio of 2:1 is typical, with some vendors claiming 2.6:1 or 3:1.
|
|
A virtual tape library (VTL) is a data storage virtualization technology used typically for backup and recovery purposes. A VTL presents a storage component (usually hard disk storage) as tape libraries or tape drives for use with existing backup software. Virtualizing the disk storage as tape allows integration of VTLs with existing backup software and existing backup and recovery processes and policies. The benefits of such virtualization include storage consolidation and faster data restore processes.
|
|
The LTO-4 specification added a feature to allow LTO-4 drives to encrypt data before it is written to tape. All LTO-4 drives must be aware of encrypted tapes, but are not required to support the encryption process. All current LTO manufacturers support encryption natively enabled in the tape drives using Application Managed Encryption (AME). The algorithm used by LTO-4 is AES-GCM, which is an authenticated, symmetric block cipher.
|
|
In computing, external memory algorithms or out-of-core algorithms are algorithms that are designed to process data that are too large to fit into a computer's main memory at once. Such algorithms must be optimized to efficiently fetch and access data stored in slow bulk memory (auxiliary memory) such as hard drives or tape drives, or when memory is on a computer network. External memory algorithms are analyzed in the external memory model.
|
|
On 29 September 1964 the ICT 1900 range was announced in a filmed presentation, scripted by Antony Jay. The following week two working systems were demonstrated at the Business Equipment Exhibition, Olympia. The first commercial sale was made in 1964 to the Morgan Crucible Company, comprising a 16K word 1902 with an 80-column 980-card/minute reader, a card punch, a 600 line/min printer and 4 x 20kchar/s tape drives.
|
|
ATA Packet Interface (ATAPI) is a protocol that has been added to Parallel ATA and Serial ATA so that a greater variety of devices can be connected to a computer than with the ATA command set alone. It carries SCSI commands and responses through the ATA interface. ATAPI devices include CD-ROM and DVD-ROM drives, tape drives, magneto-optical drives, and large-capacity floppy drives such as the Zip drive and SuperDisk drive.
|
|
Besides the operator's console, the only I/O devices connected to the UNIVAC I were up to 10 UNISERVO tape drives, a Remington Standard electric typewriter and a Tektronix oscilloscope. The UNISERVO was the first commercial computer tape drive commercially sold. It used data density 128 bits per inch (with real transfer rate 7,200 characters per second) on magnetically plated phosphor bronze tapes. The UNISERVO could also read and write UNITYPER created tapes at 20 bits per inch.
|
|
Symbolic Programming System (SPS), was the assembler offered when IBM originally announced 1401 as a punched-card-only computer. SPS had different mnemonics and a different fixed input format from Autocoder. It lacked Autocoder's features and was generally used later only on machines that lacked tape drives, that is, punched-card only. Autocoder coding sheet 1401 Autocoder is the most well known Autocoder, undoubtedly due in part to the general success of that series of machines.
|
|
Sound output was through a small built-in speaker. As was common at the time, it used a common tape recorder instead of disk/tape drives. Similarly, a television was needed as a display - but this was in black and white only, rather than the colour supported by competing models such as the Spectrum. The Jupiter Ace was based on the Zilog Z80, which the designers had previous experience of from working on the Sinclair ZX81 and ZX Spectrum.
|
|
In these, the tall cabinet sitting behind a white Formica-covered table held two somewhat smaller metal boxes holding the same instrumentation, a Tektronix display oscilloscope over the "front panel" on the user's left, a bay for interfaces over two LINC-Tape drives on the user's right, and a chunky keyboard between them. The standard program development software (an assembler/editor) was designed by Mary Allen Wilkes; the last version was named LAP6 (LINC Assembly Program 6).
|
|
A noteworthy feature of the LINC was the LINCtape. It was a fundamental part of the machine design, not an optional peripheral, and the machine's OS relied on it. The LINCtape can be compared to a linear diskette with a slow seek time. The magnetic tape drives on large machines of the day stored large quantities of data, took minutes to spool from end to end, but could not reliably update blocks of data in place.
|
|
The ruling was foreshadowed by New Scientist shortly after the British patent was granted to Pavel in 1982. Claiming a "monopoly" on personal stereo equipment, the magazine cautioned that his application might prove too broad and of no practical legal value. "Sony's breakthrough with Walkman was in the players high quality reproduction, low powered consumption and the tape drives ability to run smoothly, even when the wearer runs." Details for which, the magazine noted, were absent in Pavel's patent.
|
|
They spent about a year looking for more funding, facilities, documentation, and expertise. Pete Worden, director of NASA's Ames Research Center, agreed to store the tape drives and tapes in unused warehouse space until funding and facilities could be found to begin the restoration project. In April 2007, the Jet Propulsion Laboratory released the tapes to the custody of Ames Research Center. Evans also transferred the ownership of the FR-900 drives to Wingo and Cowing.
|
|
Access methods for DASD include sequential, indexed, and direct. Direct access contrasts with the sequential access method used in tape drives. A record on a DASD can be accessed without having to read through intervening records from the current location, whereas reading anything other than the "next" record on tape requires skipping over intervening records, and requires a proportionally long time to access a distant point in a medium. The DASD storage class includes both fixed and removable media.
|
|
Iperius Backup is a backup software for Windows PCs and Servers, databases and virtual machines. It allows to make automatic backups of files and folders on many devices: external USB hard drives, RDX drives, NAS, LTO tape drives, networked computers, Cloud storage, Amazon S3, Google Drive and FTP servers. Iperius Backup includes drive imaging capabilities, backup of SQL Server, MySQL, PostgreSQL, Oracle databases, backup of Microsoft Exchange servers, backup and replication of VMware ESXi, vCenter, ESXi Free and Hyper-V virtual machines.
|
|
Network Direct Attached Storage (NDAS) is a proprietary storage area network system, originally marketed by the company Ximeta, for connecting external digital storage devices such as hard-disks, flash memory and tape drives via the Ethernet family of computer networks. Unlike other more common forms of networked storage, NDAS does not use TCP/IP to communicate over the network. Instead a Lean Packet Exchange (LPX) protocol is used. NDAS also supports some limited RAID functions such as aggregation and mirroring.
|
|
Westinghouse Disk Utility, popularly called WDU, is a copy/backup/restore program for IBM's DOS, DOS/VS, and DOS/VSE environments. In 1978, it was reported that WDU, a product of Westinghouse Electric Corporation, was in use at over 3,000 sites. Originally designed for IBM's DOS, Westinghouse continued developing it for subsequent generations, including DOS/VS, DOS/VSE, and VM/CMS. The product offered a wide variety of backup and copy options, data streaming, alternating tape drives, and an ability to create archives.
|
|
In today's world of standard interfaces and portable systems, this may not seem such a radical goal; but at the time, it was revolutionary. Before System/360, each computer model often had its own specific devices and programs that could not be used with other systems. Buying a bigger CPU also meant buying new printers, card readers, tape drives, etc. In addition, customers would have to rewrite their programs to run on the new CPU, something customers often balked at.
|
|
The T10000D drive was announced in September 2013 with a native, non-compressed 8.5 TB capacity using the same T10000 T2 cartridge. The T10000E drive was expected in 2017 with capacity in the 12-16 TB range; however, development was cancelled in 2016. Oracle continue to feature the model T10000D on their website for use in select models of StorageTek robotic tape libraries, but Oracle has adopted LTO-8 tape drives for future capacity expansion on many of their automated libraries.
|
|
It was founded in 1980 as "Overland Data" in San Diego, California, and is a provider of data protection appliances for midrange and distributed enterprises. Overland’s award-winning products include NEO SERIES tape libraries, REO SERIES disk-based appliances with Virtual Tape Library (VTL) capabilities, Snap SAN storage area network- based appliances and SnapServer network-attached storage-based appliances. Overland sells its products through leading OEMs, commercial distributors, storage integrators and value-added resellers. Overland originally manufactured IBM-compatible 9-track tape drives.
|
|
In January 2000, Overland acquired Tecmar and its line of small system tape drives including the WangTek and WangDAT brands. Following smaller acquisitions of disk-based product lines, in June 2008, Overland acquired Snap Server from Adaptec. In January 2009, Eric Kelly, a board member since 2007 and the head of its recently acquired SnapServer NAS line, became CEO of Overland Storage.Former Snap Boss Named Overland CEO, By Joseph Kovar Other executive team changes in 2009 included Jillian Mansolf, formerly of Dell Inc.
|
|
In Exec 8, work is organized into jobs, called "runs," which are scheduled based on their priority and need for lockable resources such as Uniservo tape drives or Fastrand drum files. The control language syntax uses the "@" symbol (which Univac called "the master space") as the control statement recognition symbol. It was immediately followed by the command or program name, then a comma and any option switches. After a space character, the remainder of the statement differed for particular commands.
|
|
The tape transport was followed by the 405 Card Reader and the 415 Card Punch,Model numbers for CDC's Reader & Punch: followed by a series of tape drives and drum printers, all of which were designed in-house. The printer business was initially supported by Holley Carburetor in the Rochester, Michigan suburb outside of Detroit. They later formalized this by creating a jointly held company, Holley Computer Products. Holley later sold its stake back to CDC, the remainder becoming the Rochester Division.
|
|
Between active control of powerful reel motors and vacuum control of these U-shaped tape loops, extremely rapid start and stop of the tape at the tape-to-head interface could be achieved. When active, the two tape reels thus fed tape into or pulled tape out of the vacuum columns, intermittently spinning in rapid, unsynchronized bursts resulting in visually striking action. Stock shots of such vacuum-column tape drives in motion were widely used to represent "the computer" in films and television.
|
|
Langan, Patricia A., America's Fastest Growing Company, Fortune, August 13, 1990 Conner Peripherals were also one of the first companies to produce IDE specification AV (audio/visual) hard drives for a low cost, such as the 420 megabyte AV in 1995-1996, and was the first to produce drives with a native (no external adapter) IEEE 1394 FireWire interface. The company also started manufacturing tape drives in 1993, when it purchased Archive Corporation. In 1996, Conner Peripherals was acquired by Seagate.
|
|
UNIVAC continued to use the name UNISERVO for later models of tape drive (e.g., UNISERVO II, UNISERVO IIIC, UNISERVO VIII-C) for later computers in their product line. The UNISERVO II could read metal tapes from the UNIVAC I as well as use higher density PET film base/ferric oxide media tapes that became the industry standard. While UNIVAC was first with computer tape, and had higher performance than contemporary IBM tape drives, IBM was able to set the data interchange standard.
|
|
While the architectures differ, the machines in the same class use the same electronics technologies and generally use the same peripherals. Tape drives generally use 7-track format, with the IBM 727 for vacuum tube machines and the 729 for transistor machines. Both the vacuum tube and most transistor models use the same card readers, card punches, and line printers that were introduced with the 701. These units, the IBM 711, 721, and 716, are based on IBM accounting machine technology and even include plugboard control panels.
|
|
Additionally, drivers were made available to connect and use more HP-IB devices: hard disc and tape drives, plus impact and matrix printers. This gave some business-growth scale-ability to the HP250 product line. The HP250 was advertised in 1978 and was promoted more in Europe as an easy-to-use, small space, low cost business system, and thus sold better in Europe. The next-gen HP250 was the HP260 which lost the table, embedded keyboard, and CRT for a small stand-alone box.
|
|
During the 1980s, longer tape lengths such as became available using a much thinner PET film. Most tape drives could support a maximum reel size of . CDC used IBM compatible 1/2 inch magnetic tapes, but also offered a 1 inch wide variant, with 14 tracks (12 data tracks corresponding to the 12 bit word of CDC 6000 series peripheral processors, plus two parity bits) in the CDC 626 drive. A so-called mini-reel was common for smaller data sets, such as for software distribution.
|
|
When active, the two tape reels thus fed tape into or pulled tape out of the vacuum columns, intermittently spinning in rapid, unsynchronized bursts resulting in visually striking action. Stock shots of such vacuum-column tape drives in motion were widely used to represent "the computer" in movies and television. Early half-inch tape had seven parallel tracks of data along the length of the tape, allowing six-bit characters plus one bit of parity written across the tape. This was known as seven-track tape.
|
|
UNIVAC II at U. S. Navy Electronics Supply Office The UNIVAC II was an improvement to the UNIVAC I that UNIVAC first delivered in 1958. The improvements included core memory of 2,000 to 10,000 words, UNISERVO II tape drives which could use either the old UNIVAC I metal tapes or the new PET tapes, and some of the circuits were transistorized although it was still a vacuum tube computer. It was fully compatible with existing UNIVAC I programs for both code and data. It weighed about .
|
|
Parasitic eddy currents cannot form in the rotor as it is totally ironless, although iron rotors are laminated. This can greatly improve efficiency, but variable-speed controllers must use a higher switching rate (>40 kHz) or DC because of decreased electromagnetic induction. These motors were originally invented to drive the capstan(s) of magnetic tape drives, where minimal time to reach operating speed and minimal stopping distance were critical. Pancake motors are widely used in high-performance servo-controlled systems, robotic systems, industrial automation and medical devices.
|
|
LTO-3 and LTO-4 use a similar format with 1,616,940-byte blocks. The tape drives use a strong error correction algorithm that makes data recovery possible when lost data is within one track. Also, when data is written to the tape it is verified by reading it back using the read heads that are positioned just "behind" the write heads. This allows the drive to write a second copy of any data that fails the verify without the help of the host system.
|
|
General Motors' Research division produced GM-NAA I/O for its IBM 701 in 1956 (from a prototype, GM Operating System, developed in 1955), and updated it for the 701's successor. In 1960 the IBM user association SHARE took it over and produced an updated version, SHARE Operating System. Finally IBM took over the project and supplied an enhanced version called IBSYS with the IBM 7090 and IBM 7094 computers. IBSYS required 8 tape drives (fewer if the system had one or more disk drives).
|
|
The 3592 line of tape drives and media is not compatible with the IBM 3590 series of drives, which it superseded. This series can store up to 20 TB of data (uncompressed) on a cartridge and has a native data transfer rate of up to 400 MB/s. Like the 3590 and 3480 before it, this tape format has half inch tape spooled onto 4-by-5-by-1 inch data cartridges containing a single reel. A take-up reel is embedded inside the tape drive.
|
|
Stock shots of such vacuum-column tape drives in motion were widely used to represent mainframe computers in movies and television. Quarter inch cartridges, a data format commonly used in the 1980s and 1990s. Most modern magnetic tape systems use reels that are much smaller than the 10.5 inch open reels and are fixed inside a cartridge to protect the tape and facilitate handling. Many late 1970s and early 1980s home computers used Compact Cassettes, encoded with the Kansas City standard, or alternate encodings.
|
|
Rush was Flaherty's partner, an IRS agent who oversaw the accounting of the payouts and the arrangement of the winner's tax obligations. Each episode also took place in a different city around the country. The opening titles for the show featured large banks of computers and tape drives. Above what appeared to be a trading floor (similar to what one would see at a stock exchange) were large electronic toteboards showing the latest prizes, the winners's names, and the countries in which they lived.
|
|
The Elea 9000 had three generations: Elea 9001 (Macchina Zero - Machine Zero) prototype was made with vacuum tubes, but used germanium transistors for the tape drive system. The system was completed in spring 1957 and was later sent to Ivrea where for six years it controlled the Olivetti production warehouses. The machine was a prototype. Elea 9002 (Macchina 1V - Machine 1V), 1958, was a prototype with printed circuits and optimized design, much faster than its predecessor and utilizing silicon transistors for the management of tape drives.
|
|
According to Massaro, Adkisson proposed a smaller size and began working with cardboard mockups before the Wang meeting. George Sollman suggests the size was the average of existing tape drives of the era. It is an urban legend that the physical size came about when they met with Wang at a bar in Boston; when he was asked what size would be appropriate, Wang pointed to a cocktail napkin—there was no such meeting. The new drive of this size stored 98.5 KB, later increased to 110 KB by adding five tracks.
|
|
In purely numeric mode, the tape reading and writing was performed at 240,000 digits per second. All tape drives were “industry” (meaning IBM) compatible and contained automatic error-checking systems. Either 7 or 9 channel tape code could be used and tapes could be written in the forward direction and read in both forward and reverse directions. # Mass storage was available in the form of both magnetic drum and magnetic disc with an interchangeable disc-pack capacity of 7.25 MB at a data interchange rate of 156 kbit/s.
|
|
A large memory buffer can be used to queue the data. In the past, the host block size affected the data density on tape, but on modern drives, data is typically organized into fixed sized blocks which may or may not be compressed and/or encrypted, and host block size no longer affects data density on tape. The Linear Tape-Open article covers this. Modern tape drives offer a speed matching feature, where the drive can dynamically decrease the physical tape speed as needed to avoid shoe-shining.
|
|
However, high-end disk controllers often have their own on-board cache of the hard disk drive's data blocks. Finally, a fast local hard disk drive can also cache information held on even slower data storage devices, such as remote servers (web cache) or local tape drives or optical jukeboxes; such a scheme is the main concept of hierarchical storage management. Also, fast flash-based solid-state drives (SSDs) can be used as caches for slower rotational-media hard disk drives, working together as hybrid drives or solid-state hybrid drives (SSHDs).
|
|
Most models had two tape drives, which greatly facilitated revision and enabled features such as mail merge. An add-on module added a third tape station, to record the combined output of playback from the two stations. The MT/ST automated word wrap, but it had no screen, automated hyphenation (soft hyphens were available), or concept of the page; pages had to be divided and numbered by the human operator during playback. Instruction manuals taught the operator the importance of listening to the sounds of the machine during playback.
|
|
A hallmark of the genre is interchangeability: Tapes recorded with one tape drive are generally readable on another drive, even if the tape drives were built by different manufacturers. Magstar tapes and drives exist in 128, 256 and 384-track versions. It is important to be aware that the tape is written at the drive's defined density and can only be read in a drive of the same model type or a higher version model. So a tape written in the H drive can only be read in an H drive.
|
|
These modified Selectrics featured electronically interfaced typing mechanisms and keyboards and thus provided a typing station with IBM quality that was easily connected to a computer. An ICS Astrotype system consisting of a PDP-8/L system with 8K 12-bit words of memory, plus two simplified TU55 tape drives (branded Astrotype). In October, 1968, at the Business Equipment Manufacturers Association trade show at McCormick Place in Chicago, the company announced its first propriety product, a typing automation product called Astrotype.The Ann Arbor News, 1 November 1968 "Local Firm automates Typing"McCracken, Henry.
|
|
The original LTO specification describes a data compression method LTO-DC, also called Streaming Lossless Data Compression (SLDC).. It is very similar to the algorithm ALDC. which is a variation of LZS. LTO-1 through LTO-5 are advertised as achieving a "2:1" compression ratio, while LTO-6 and LTO-7, which apply a modified SLDC algorithm using a larger history buffer, are advertised as having a "2.5:1" ratio. This is inferior to slower algorithms such as gzip, but similar to lzop and the high speed algorithms built into other tape drives.
|
|
In August 1999, Belluzzo left SGI to head Microsoft's MSN division, and then the whole Consumer business, leading several emerging efforts, including the launch of the first Xbox. In February 2001, he became president and chief operating officer of Microsoft, running the day-to-day business during the critical CEO transition from Bill Gates to Steve Ballmer. In September 2002, he was appointed CEO at Quantum Corp., where he managed the transformation from a Tape Drives to a Storage Systems Company, leader in Back-up, Recovery, and Archive solutions.
|
|
Soundstream-modified Honeywell 5600e Instrumentation Tape Drives (HTD) used custom high-frequency 18-track record and playback heads. The two outer tracks were reserved for ancillary data - SMPTE time code and the like. The remaining sixteen tracks were used to record up to eight channels of digital audio - two redundant tracks for each audio channel. The two tracks in a redundant track pair were separated as widely as possible to minimize playback errors due to tape defects (dropouts) - audio channel one was recorded on tracks 1 and 9.
|
|
M-DISC is a DVD-based format that claims to retain data for 1,000 years, but writing to it requires special optical disc drives and reading the data it contains requires increasingly uncommon optical disc drives, in addition the company behind the format went bankrupt. Data stored on LTO tapes require periodic migration, as older tapes cannot be read by newer LTO tape drives. RAID arrays could be used to protect against failure of single hard drives, although care needs to be taken to not mix the drives of one array with those of another.
|
|
Various optional OIO boards were produced for the PERQ 1 and 2: 3RCC OIO boards provided a 16-bit parallel PERQlink interface (intended for downloading microcode from another PERQ at boot time) plus Ethernet and/or a Canon CX laser printer controller. Thus, a PERQ 2 could be configured with two Ethernet ports (EIO plus OIO). A dot-matrix printer could also be connected to the RS-232 or IEEE-488 ports. Other third-party OIO boards were produced to interface to other devices, such as QIC-02 tape drives or video cameras.
|
|
Typically there were two strings and two DCs processing in parallel, one on standby in case of a malfunction in its counterpart. Either string could feed either DC for further equipment reliability. The software was written in a proprietary version of the programming language JOVIAL termed JSS JOVIAL. The system was updated over time to change tape drives to disk cartridges and single-line printers to multi-line printers. The memory in the H5118ME was expanded at least twice to the system maximum of 512,000 18-bit words.
|
|
The 1551 is less common than other Commodore disk drives. The 1541 was more readily available as it is compatible with the popular C64 and VIC-20, so many people opted to use 1541s with the Plus/4. Since the 1551 is compatible only with the Plus/4, which was a poor seller in the United States, few were made. In Europe, the Plus/4 was much more successful, but because tape drives were the most popular storage device in Europe in the 1980s, the 1551 was not very popular in Europe either.
|
|
System, pg. 8 The core memory was backed by one or two magnetic drums with 16k words each.System, pg. 18 Various offline input/output included magnetic disks, tape drives, punched cards, punched tape and printers. Most of the Orion's instruction set used a three- address form, with sixty-four 48-bit accumulators. Each program had its own private accumulator set which were the first 64 registers of its address space, which was a reserved contiguous subset of the physical store, defined by the contents of a "datum" relocation register.
|
|
A single head assembly having two heads was used for access to all the platters, yielding an average access time of just under 1 second. The RAMAC disk drive created a new level in the computer data hierarchy, today known as secondary storage, less expensive and slower than main memory (then typically core or drum) but faster and more expensive than tape drives. Subsequently there was a period of about 20 years in which other technologies competed with disks in the secondary storage marketplace, for example tape strips, e.g., NCR CRAM, tape cartridges, e.g.
|
|
As some data can be compressed to a smaller size than the original files, it has become commonplace when marketing tape drives to state the capacity with the assumption of a 2:1 compression ratio; thus a tape with a capacity of 80 GB would be sold as "80/160". The true storage capacity is also known as the native capacity or the raw capacity. The compression ratio actually achievable depends on the data being compressed. Some data has little redundancy; large video files, for example, already use compression and cannot be compressed further.
|
|
EXE was included which was compatible with MS-DOS 5.0. For compatibility reasons, Windows NT 3.1 shipped with a few 16-bit applications, like Microsoft Write or EDLIN.. Windows NT 3.1, being an all-new operating system for which no previous drivers could be used, includes a wealth of drivers for various common components and peripherals. This includes common SCSI devices like hard drives, CD-ROM drives, tape drives and image scanners, as well as ISA devices like graphics cards, sound cards and network cards. The PCI bus, however, is expressly not supported.
|
|
Burroughs B205 hardware has appeared as props in many Hollywood television and film productions from the late 1950s. For example, a B205 console was often shown in the television series Batman as the Bat Computer; also as the computer in Lost in Space. B205 tape drives were often seen in series such as The Time Tunnel and Voyage to the Bottom of the Sea."B205 On Screen""Starring the Computer: Burroughs B205" Craig Ferguson, American talk show host, comedian and actor was a Burroughs apprentice in Cumbernauld, Scotland.
|
|
Simple QIOs, such as read or write requests, are either serviced by the kernel itself or by device drivers. Certain more complicated requests, specifically those involving tape drives and file-level operations, were originally executed by an Ancillary Control Processor (ACP) (a special purpose task with its own address mapping). The Files-11 ODS-1 file system on RSX-11 was implemented by a subroutine library that communicated with a task named F11ACP using a special set of QIOs called the "ACP QIOs." The equivalent functionality for controlling magnetic tape devices was provided by a task named MTAACP.
|
|
Hierarchical storage management (HSM) is a data storage technique that automatically moves data between high-cost and low-cost storage media. HSM systems exist because high-speed storage devices, such as solid state drive arrays, are more expensive (per byte stored) than slower devices, such as hard disk drives, optical discs and magnetic tape drives. While it would be ideal to have all data available on high-speed devices all the time, this is prohibitively expensive for many organizations. Instead, HSM systems store the bulk of the enterprise's data on slower devices, and then copy data to faster disk drives when needed.
|
|
A Change Sequence Mode (CSM) instruction stored the next instruction address in a memory location and loaded the instruction counter from another memory location. This provided a simple switch between threads within a program, similar to the sequence/cosequence behaviour of the Honeywell 800 series. While the H200 supported operation with just a console, card reader and punch like the IBM 1401, the generic Input-Output instructions also supported line printers and magnetic tape drives. IO instructions left punctuation bits unchanged, reading or writing only data (and parity) bits into memory, and terminating on any record mark encountered.
|
|
The H200 was commonly used as a spooling computer associated with a larger Honeywell 800 series machine. The H1800-II consisted of an H1800 mainframe equipped only with magnetic tape drives and an online adaptor (OLA) connection to a satellite H200 to simulate a card reader for reading low volumes of job control cards. The LINK program running on the H200 handled the OLA,"On-Line Adapter (connects a Series 200 processor to a Honeywell 800 or 1800)" copied punched cards or punched paper tape to magnetic tape, and copied records from magnetic tape to card punch or to line printer.
|
|
Atari 1020 four-color Plotter During the lifetime of the 8-bit series, Atari released a large number of peripherals including cassette tape drives, 5.25-inch floppy drives, printers, modems, a touch tablet, and an 80-column display module. Atari's peripherals used the proprietary Atari SIO port, which allowed them to be daisy chained together into a single string. A primary goal of the Atari computer design was user- friendliness which was assisted by the SIO bus. Since only one kind of connector plug is used for all devices the Atari computer was easy for novice users to expand.
|
|
Compact cassettes were logically, as well as physically, sequential; they had to be rewound and read from the start to load data. Early cartridges were available before personal computers had affordable disk drives, and could be used as random access devices, automatically winding and positioning the tape, albeit with access times of many seconds. Experienced computer gamers could tell a lot by listening to the loading noise from the tape. In 1984 IBM introduced the 3480 family of single reel cartridges and tape drives which were then manufactured by a number of vendors through at least 2004.
|
|
With the Medium System, a computer could be simultaneously running a batch payroll system, inputting bank checks on a MICR reader sorter, compiling COBOL applications, supporting on-line transactions, and doing test runs on new applications (colloquially called 'the mix', as the console command '`MX`' would shows that jobs were executing). It was not unusual to be running eight or ten programs on a medium-size B2500. Medium System installations often had tape clusters (four drives integrated into a mid-height cabinet) for magnetic tape input and output. Free-standing tape drives were also available, but they were much more expensive.
|
|
Several of the occupiers had privileged backgrounds, coming from wealthy West Indian families; among those arrested and convicted were Roosevelt Douglas, who later became Prime Minister of Dominica, and who was a son of one of the richest men in Dominica. Also arrested was Anne Cools, now a Canadian Senator. Deeply involved also was student Cheddi "Joey" Jagan Jr., son of Guyana's prime minister. Some claim that the computer lab was not damaged, except for several million computer punched cards that were sent fluttering to the street below; but a Canadian Broadcast Corporation documentary shows smashed computer tape drives and extensive fire damage.
|
|
Backup-to-disk refers to technology that allows one to back up large amounts of data to a disk storage unit. The backup-to-disk technology is often supplemented by tape drives for data archival or replication to another facility for disaster recovery. Additionally, backup-to-disk has several advantages over traditional tape backup for both technical and business reasons explained later in this article. With continued improvements in storage devices to provide faster access and higher storage capacity, a prime consideration for backup and restore operations, backup-to-disk will become more prominent in organizations.
|
|
For most mainframe data centers, the storage capacity varies, however protecting its business and mission critical data is always vital. Most current VTL solutions use SAS or SATA disk arrays as the primary storage component due to their relatively low cost. The use of array enclosures increases the scalability of the solution by allowing the addition of more disk drives and enclosures to increase the storage capacity. The shift to VTL also eliminates streaming problems that often impair efficiency in tape drives as disk technology does not rely on streaming and can write effectively regardless of data transfer speeds.
|
|
DLm has been developed by EMC Corporation, while Luminex has gained popularity and wide acceptance by teaming with Data Domain to provide the benefits of data deduplication behind its Channel Gateway platform. With the consequent reduction in off-site replication bandwidth afforded by deduplication, it is possible and practical for this form of virtual tape to reduce recovery point objective time and recovery time objective to near zero (or instantaneous). Outside of the mainframe environment, tape drives and libraries mostly featured SCSI. Likewise, VTLs were developed supporting popular SCSI transport protocols such as SPI (legacy systems), Fibre Channel, and iSCSI.
|
|
Most Amdahl mainframe customers would purchase storage devices (hard disk and tape drives) from IBM or its plug-compatible competitors. Amdahl first attempted a merger with one of the largest of these vendors, Memorex, in 1979. After this deal fell through, Amdahl went much further on a deal to merge with Colorado-based Storage Technology Corporation (STC). The deal was approved by the boards of both companies, and detailed plans were in place to implement the merger, when Fujitsu, an important partner and major shareholder of Amdahl at the time, objected to the deal which forced it to collapse.
|
|
Backup Exec recovers data, applications, databases, or systems, from an individual file, mailbox item, table object, to an entire server. Current versions of the software support Microsoft, VMware, and Linux, among a longer list of supported hardware and software. When used with tape drives, Backup Exec uses the Microsoft Tape Format (MTF), which is also used by Windows NTBackup, backup utilities included in Microsoft SQL Server, and many other backup vendors and is compatible with BKF. Microsoft Tape Format (MTF) was originally Maynard's (Backup Exec's first authors) proprietary backup Tape Format (MTF) and was later licensed by Microsoft as Windows standard tape format.
|
|
The random-access, low- density storage of disks was developed to complement the already used sequential-access, high-density storage provided by tape drives using magnetic tape. Vigorous innovation in disk storage technology, coupled with less vigorous innovation in tape storage, has reduced the difference in acquisition cost per terabyte between disk storage and tape storage; however, the total cost of ownership of data on disk including power and management remains larger than that of tape. Disk storage is now used in both computer storage and consumer electronic storage, e.g., audio CDs and video discs (VCD, standard DVD and Blu-ray).
|
|
ATAPI devices are also "speaking ATA", as the ATA physical interface and protocol are still being used to send the packets. On the other hand, ATA hard drives and solid state drives do not use ATAPI. ATAPI devices include CD-ROM and DVD-ROM drives, tape drives, and large-capacity floppy drives such as the Zip drive and SuperDisk drive. The SCSI commands and responses used by each class of ATAPI device (CD-ROM, tape, etc.) are described in other documents or specifications specific to those device classes and are not within ATA/ATAPI or the T13 committee's purview.
|
|
Wingo and Cowing quickly found more expertise in Ken Zin, a U.S. Army veteran who had long experience in working with analog tape machines, including the FR-900 series. By coincidence, Zin's brother worked at NASA Ames Research Center and it is via this coincidence that Wingo and Cowing initially got in touch with Zin. With the assistance of Ken Davidian at NASA Headquarters, funding was found in 2008 for a pilot project to show that the drives could be repaired, and that images could be recovered from the original tapes. The first task was to methodically disassemble and clean the tape drives.
|
|
After another month of repairing and replacing parts, testing and tuning mechanisms, the project got the first solid result that the tapes were good. Each tape starts with a short standard-format audio clip of the operator, and the tape drives were able to read the audio signal. (Hear a sample of the audio.) This does not use the video heads that are needed to read the Lunar Orbiter data off the tape, but this demonstrated that the tapes had not deteriorated and that many of the sub-systems of the tape drive were in good working order.
|
|
This documentation would make it possible for the team to understand the correct procedures for repairing the tape drives and aligning the mechanics. At this point in the restoration, the demodulation of the tapes had become the biggest issue. The team was not sure if the demodulation board that came with the system was the correct one, if they needed a different one, or if they needed this one and another one. At the same time, they discovered a tape, which, from the audio clip at the start, sounded as if it contained a demodulated recording of one of the images.
|
|
With these results, more funds were released—another $150,000 to complete a major restoration of the drives and to create the demodulation hardware needed for the other tapes. Gregory Schmidt, deputy director of the NASA Lunar Science Institute at Ames said, "Now that we've demonstrated the capability to retrieve images, our goal is to complete the tape drives' restoration and move toward retrieving all of the images on the remaining tapes". Within a month, the next round of funding came through and restoration began in earnest. The heads, capstan and rotor motors were being restored by two different companies.
|
|
DEC's first native UNIX product was V7M (for modified) or V7M11 for the PDP-11 and was based on version of UNIX 7th Edition from Bell Labs. V7M, developed by DEC's original Unix Engineering Group (UEG), Fred Canter, Jerry Brenner, Stettner, Bill Burns, Mary Anne Cacciola, and Bill Munson – but the work of primarily Canter and Brenner. V7M contained many fixes to the kernel including support for separate instruction and data spaces, significant work for hardware error recovery, and many device drivers. Much work was put into producing a release that would reliably bootstrap from many tape drives or disk drives.
|
|
Many programs can clone a disk, or make an image, from within the running system, with special provision for copying open files; but an image cannot be restored onto the Windows System Drive under Windows. A disc cloning program must have device drivers or equivalent for all devices used. The manufacturers of some devices do not provide suitable drivers, so the manufacturers of disk cloning software must write their own drivers, or include device access functionality in some other way. This applies to tape drives, CD and DVD readers and writers, and USB and FireWire drives.
|
|
CPI produced several train printers under the CDC and Fastrain brands, including the CDC Model 512 (1967), the Fastrain A 1200 LPM (1969) and the Fastrain 9372-III 2000 LPM (1976). In 1977, CPI began manufacturing printers at a factory in Stevenage, Herts, UK that was originally used for the manufacture of ICL1900 computers. By 1979, the factory also made 9-track tape drives which were used in ICL and CDC computers, and were sold with industry-standard interfaces for use with other manufacturer's computers. In 1982, CDC acquired a controlling interest in Centronics in exchange for CPI and $25 million in cash.
|
|
Expansion systems included a disk controller which could run one to four 25 MB hard drives, a communications card for up to 16 terminals each, card readers, printer outputs and tape drives. A significant aspect of the design was its memory paging system, which used conventional hard drives rather than the custom memory drums or specialized hard disks with multiple read/write heads (a random- access disk, or RAD). Making this work with reasonable performance required significant efforts to tune the input/output routines to avoid unnecessary reads and writes, which was handled in the system's hardware memory management unit.
|
|
In computer science, a computer is CPU-bound (or compute-bound) when the time for it to complete a task is determined principally by the speed of the central processor: processor utilization is high, perhaps at 100% usage for many seconds or minutes. Interrupts generated by peripherals may be processed slowly, or indefinitely delayed. The concept of CPU-bounding was developed during early computers, when data paths between computer components were simpler, and it was possible to visually see one component working while another was idle. Example components were CPU, tape drives, hard disks, card- readers, and printers.
|
|
To provide high start, stop and seek performance, several feet of loose tape was played out and pulled by a suction fan down into two deep open channels on either side of the tape head and capstans. The long thin loops of tape hanging in these vacuum columns had far less inertia than the two reels and could be rapidly started, stopped and repositioned. The large reels would move as required to keep the slack tape in the vacuum columns. Later, most tape drives of the 1980s introduced the use of an internal data buffer to somewhat reduce start-stop situations.
|
|
Bus and tag cables Bus and Tag is an "IBM standard for a computer peripheral interface", and was commonly used to connect their mainframe computers to peripheral devices such as line printers, disk storage, and magnetic tape drives. The technology uses two sets of thick, multi-connector copper cables, one set, carrying data, called the bus, and the other set, carrying control information, called the tag. Bus and tag terminator blocks Bus and Tag cables are "daisy chained"; and one interface can attach up to eight peripheral control units. The last control unit in the chain must have a terminator plug.
|
|
The 615-100 Series integrated a complete data processing system had 16KB or 32KB of short rod memory, 80-column punched card reader or paper tape reader, two 5MB removable disc drives, 600-line per minute line printer. The system could be provided with a punched paper tape reader, or an external card reader/punch, and also allowed for the attachment of multiple 9 track 1/2 inch reel to reel magnetic tape drives. Two more disk drives could be attached to the system. The Century series used an instruction set with two instruction lengths: 4 bytes (32 bits) and 8 bytes (64 bits).
|
|
Holberton used a deck of playing cards to develop the decision tree for the binary sort function, and wrote the code to employ a group of ten tape drives to read and write data as needed during the process. She wrote the first statistical analysis package, which was used for the 1950 US Census. In 1953 she was made a supervisor of advanced programming in a part of the Navy’s Applied Math lab in Maryland, where she stayed until 1966. Holberton worked with John Mauchly to develop the C-10 instruction set for BINAC, which is considered to be the prototype of all modern programming languages.
|
|
BOS was one of four System/360 Operating System versions developed by the IBM General Products Division (GPD) in Endicott, New York to fill a gap at the low end of the System/360 line when it became apparent that OS/360 was not able to run on the smallest systems. BPS (Basic Programming support) was designed to run on systems with a minimum of 8,192 bytes of memory and no disk. BOS was intended for disk systems with at least 8,192 bytes and one 2311 disk drive. DOS and TOS were developed for systems with at least 16,384 bytes and either disks or tape drives.
|
|
Since 1994 when it acquired the Digital Linear Tape product line from Digital, Quantum has sold tape storage products, including tape drives, media and automation. In 2007, Quantum discontinued development of the DLT line in favor of Linear Tape- Open,LTO-5 On Course for 2009 which it began selling in 2005 following its acquisition of Certance. In 2012, Quantum introduced its Scalar LTFS (Linear Tape File System) appliance, which offers new modes of portability and user accessibility for archived content on LTO tape.Article from The Register In 2016, Quantum refreshed its Scalar LTO tape library family and added an appliance for rich media archiving.
|
|
The basic system included a microprocessor with 512 characters of read/write RAM memory, a keyboard, a CRT display and two cartridge tape drives. The system specifications, advanced for 1968 - five years before the advent of the first commercial personal computers - caused a lot of excitement in the computer industry. The System 21 was aimed, among others, at applications such as mathematical and statistical analysis, business data processing, data entry and media conversion, and educational/classroom use. The expectation was that the use of new large scale integrated circuit technology (LSI) and volume would enable Viatron to be successful at lower margins, however the prototype did not incorporate LSI technology.
|
|
Before the rise of the PCM peripheral industry, computing systems were either configured with peripherals designed and built by the CPU vendor, or designed to use vendor-selected rebadged devices. The first example of plug compatible IBM subsystems were tape drives and controls offered by Telex beginning 1965. Memorex in 1968 was first to enter the IBM plug-compatible disk followed shortly thereafter by a number of suppliers such as CDC,"Expected to produce $1 billion in revenues during fiscal 1980, CDC's peripherals business, advancing at 33% annually, is the fastest growing revenue producer within the company's diverse product line." Itel, and Storage Technology Corporation.
|
|
The performance of a RAM drive is in general orders of magnitude faster than other forms of storage media, such as an SSD, hard drive, tape drive, or optical drive. This performance gain is due to multiple factors, including access time, maximum throughput, and type of file system. File access time is greatly reduced since a RAM drive is solid state (no mechanical parts). A physical hard drive or optical media, such as CD-ROM, DVD, and Blu-ray must move a head or optical eye into position and tape drives must wind or rewind to a particular position on the media before reading or writing can occur.
|
|
A boot disk is a removable digital data storage medium from which a computer can load and run (boot) an operating system or utility program. The computer must have a built-in program which will load and execute a program from a boot disk meeting certain standards. While almost all modern computers can boot from a hard drive containing the operating system and other software, they would not normally be called boot disks (because they are not removable media). CD-ROMs are the most common forms of media used, but other media, such as magnetic or paper tape drives, ZIP drives, and more recently USB flash drives can be used.
|
|
Scanned Xetec user manuals The Fontmaster line of word processing software provides Commodore users the ability to exploit the graphics capabilities just emerging in printers of the day in order to produce documents containing a mixture of font styles, sizes and effects as well as embedded pictures. Although lacking the power and flexibility of word processors available today, it was ground-breaking in its day, winning an Outstanding Original Programming award at the 1985 Consumer Electronics Show. Fontmaster 128 was featured in the 1987 Consumer Electronics Show Software Showcase. Xetec's offerings for the Amiga include SCSI interfaces, hard drives, CD-ROM drives, streaming tape drives, and RAM expansion.
|
|
Wingo and Cowing rented two transfer trucks, loaded up the tape drives and documentation into one truck, and loaded the pallets of analog data tapes into the other truck. Cowing and Wingo then drove the trucks up to Mountain View, California, from Burbank. The drives and tapes then sat in storage for about the next year as funding for the project was sought. Since the team required a facility with proper heating and cooling, and a sink, available vacant buildings outside the gate of Ames Research Center were whittled down to two: a barber shop, and a McDonald's restaurant that had closed weeks before.
|
|
Small open reel of 9 track tape Magnetic tape was first used to record computer data in 1951 on the Eckert-Mauchly UNIVAC I. The system's UNISERVO I tape drive used a thin strip of one half inch (12.65 mm) wide metal, consisting of nickel-plated bronze (called Vicalloy). Recording density was 100 characters per inch (39.37 characters/cm) on eight tracks. Early IBM 7 track tape drives were floor- standing and used vacuum columns to mechanically buffer long U-shaped loops of tape. The two tape reels visibly fed tape through the columns, intermittently spinning 10.5 inch open reels in rapid, unsynchronized bursts, resulting in visually striking action.
|
|
Later, IBM introduced the Personal/370 (aka P/370), a single slot 32-bit MCA card that can be added to a PS/2 or RS/6000 computer to run System/370 OSs (like MUSIC/SP, VM, VSE) parallel to OS/2 (in PS/2) or AIX (in RS/6000) supporting multiple concurrent users. It is a complete implementation of the S/370 Processor including a FPU co-processor and 16 MB memory. Management and standard I/O channels are provided via the host OS/hardware. An additional 370 channel card can be added to provide mainframe- specific I/O such as 3270 local control units, 3400/3480 tape drives or 7171 protocol converters.
|
|
In September 1971, RCA decided to exit the mainframe computer business after losing about half a billion dollars trying (and failing) to compete against IBM. Most of the assets of the computer division were sold to what was then Univac. This included RCA's Spectra series of computers, various external hardware designs (such as video terminals, tape drives and punched card readers), and its operating system, Time Sharing Operating System (TSOS). TSOS may have been a better operating system from a user standpoint than any of IBM's, but at the time, operating systems were not considered something sold separately from the computer, the manufacturer included it free as part of the purchase price.
|
|
Spooling is also used to mediate access to punched card readers and punches, magnetic tape drives, and other slow, sequential I/O devices. It allows the application to run at the speed of the CPU while operating peripheral devices at their full rates speed. A batch processing system uses spooling to maintain a queue of ready-to-run tasks, which can be started as soon as the system has the resources to process them. Some store and forward messaging systems, such as uucp, used "spool" to refer to their inbound and outbound message queues, and this terminology is still found in the documentation for email and Usenet software, even though messages are often delivered immediately nowadays.
|
|
In spite of the larger tapes, less convenience, and generally more expensive media, reel-to-reel systems, which first started in the early 1940s, remained popular in audiophile settings into the 1980s, and have reestablished a specialist niche in the 21st century. Reel-to-reel tape was used in early tape drives for data storage on mainframe computers and in video tape recorders (VTRs). Magnetic tape was also used to record data signals for instrumentation purposes, beginning with the hydrogen bomb tests of the early 1950s. Studer, Stellavox, Tascam, and Denon still produced reel to reel tape recorders in the 1990s, but , only Mechlabor continues to manufacture analog reel-to-reel recorders.
|
|
The Datapoint 2200 had a built-in full-travel keyboard, a built-in 12-line, 80-column green screen monitor, and two 47 character-per-inch cassette tape drives each with 130 KB capacity. Its size, , and shape--a box with protruding keyboard--approximated that of an IBM Selectric typewriter. Initially, a Diablo 2.5 MB 2315-type removable cartridge hard disk drive was available, along with modems, several types of serial interface, parallel interface, printers and a punched card reader. Later, an 8-inch floppy disk drive was also made available, along with other, larger hard disk drives. An industry-compatible 7/9-track (user selectable) magnetic tape drive was available by 1975.
|
|
Zero seek is a mechanical engineering design component of most computer- controlled data storage devices, including floppy disk drives, tape drives, and early hard drives. Most early data storage devices were controlled primarily by stepper motors, which are able to move in very small, precise rotational movements. These movements were commonly used to define separate physical spaces where data is to be stored, such as the rotations being used to move a read/write head across the surface of a recording media to define tracks of cylinders of data on the media. Although the movement of the stepper is precise, when a device is first powered on, the computer usually cannot immediately determine where the stepper is positioned.
|
|
Invalid or incorrect data needed correction and resubmission with consequences for data and account reconciliation. Data storage was strictly serial on paper tape, and then later to magnetic tape: the use of data storage within readily accessible memory was not cost- effective until hard disk drives were first invented and began shipping in 1957. Significant developments took place in 1959 with IBM announcing the 1401 computer and in 1962 with ICT (International Computers & Tabulators) making delivery of the ICT 1301. Like all machines during this time the processor together with the peripherals – magnetic tape drives, disks drives, drums, printers and card and paper tape input and output required considerable space in specially constructed air conditioned accommodation.
|
|
The MAGPAK 9446 tape drive subsystem and associated 9401 tape cartridge was developed by SDS for the SDS 900 series and announced in May 1964 Each tape drive unit consists of two independently controlled magnetic tape drives mounted on a standard 10½-inch by 19-inch panel. Data are recorded at 7.5 inches per second and 1,400 bits per inch. The 9448 Tape Control Unit connects the tape drive unit to any Series 900 system. The tape cartridge contains approximately 600 feet of Mylar tape with two independent tracks each holding approximately 1.5 million IBM characters (6 bits plus parity) yielding a capacity of approximately 4 million six bit characters per cartridge.
|
|
An IEEE 1284 compliant printer cable, with both DB-25 and 36-pin Centronics connectors The IEEE 1284 standard allows for faster throughput and bidirectional data flow with a theoretical maximum throughput of 4 megabytes per second; actual throughput is around 2 megabytes/second depending on hardware. In the printer venue, this allows for faster printing and back- channel status and management. Since the new standard allowed the peripheral to send large amounts of data back to the host, devices that had previously used SCSI interfaces could be produced at a much lower cost. This included scanners, tape drives, hard disks, computer networks connected directly via parallel interface, network adapters and other devices.
|
|
Thus, with the ability to program their own games through these early home computers, UK developed an initial home computer game market, with games typically made by only one person with no formal experience in computer programming, known as "bedroom coders". As there were few game stores in the UK at that time, most of these coders turned to mail order, sending out copies of their games on cassette tape for use in the computer's tape drives. A market developed for companies to help such programmer sell and distribute their games. This industry took off after the release of the ZX Spectrum in 1983: by the end of that year, there were more than 450 companies selling video games on cassette compared to 95 the year before.
|
|
By that time competition from IBM had made the Philco computer operations no longer profitable for Ford, and the division was closed down. Philco 212 at the thumb The Model 212 could carry out a floating-point multiplication in 22 microseconds. Each word contained two 24-bit instructions with 16 bits of address information and eight bits for the opcode. There were 225 different valid opcodes in the Model 212; invalid opcodes were detected and halted the machine. The CPU had an accumulator register of 48 bits, three general-purpose registers of 24 bits, and 32 index registers of 15 bits. Main memory size ranged from 4K words to 64K words. Only the first model had a magnetic drum memory; later editions used tape drives.
|
|
Expensive Typewriter, written and improved between 1961 and 1962 by Steve Piner and L. Peter Deutsch, was a text editing program that ran on a DEC PDP-1 computer at MIT. Since it could drive an IBM Selectric typewriter (a letter-quality printer), it may be considered the first-word processing program, but the term word processing itself was only introduced, by IBM's Böblingen Laboratory in the late 1960s. In 1969, two software based text editing products (Astrotype and Astrocomp) were developed and marketed by Information Control Systems (Ann Arbor Michigan). Both products used the Digital Equipment Corporation PDP-8 mini computer, DECtape (4” reel) randomly accessible tape drives, and a modified version of the IBM Selectric typewriter (the IBM 2741 Terminal).
|
|
The system had a base memory of 4 KB of core memory with a 2 μs cycle time, expandable to 32 KB. It supported one to four input/output channels with up to 16 devices per channel. It offered a choice of line printers between 280 and 1250 lines per minute (lpm), a 400 cards per minute (cpm) card reader, a 160 columns per second card punch, a paper tape reader, a 2.48 MB disk storage unit, and 7 and 9-track half-inch magnetic tape drives. An optional asynchronous terminal could be attached as a console. The system supported synchronous communications at up to 9600 baud, and usually served as a remote job entry system to a larger mainframe computer.
|
|
These were 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 IBM 727 and IBM 729, were mechanically sophisticated floor-standing drives that used vacuum columns to buffer long u-shaped loops of tape. Between servo control of powerful reel motors, a low-mass capstan drive, and the low-friction and controlled tension of the vacuum columns, fast start and stop of the tape at the tape-to-head interface could be achieved: 1.5 ms from stopped tape to full speed of . The fast acceleration is possible because the tape mass in the vacuum columns is small; the length of tape buffered in the columns provides time to spin the high inertia reels.
|
|
The final ERM computer contained more than a million feet (304,800 metres) of wiring, 8,000 vacuum tubes, 34,000 diodes, 5 input consoles with MICR readers, 2 magnetic memory drums, the check sorter, a high- speed printer, a power control panel, a maintenance board, 24 racks holding 1,500 electrical packages and 500 relay packages, and 12 magnetic tape drives for 2,400-foot (731-metre) tape reels. ERM weighed about 25 tons (22.7 tonnes), used more than 80 kW of power and required cooling by an air conditioning system. By 1955, the system was still in development, but BoA was anxious to announce the project. At the time, computers (still known as "electronic brains") were all the rage; if BoA could announce that they were using them, it would convey a sense of futuristic infallibility.
|
|
The first Genigraphics systems (100 Series and 100A Series) used an array of buttons, dials, knobs and joysticks, along with a built in keyboard, as the means of user interface. The PDP-11/40 computer was housed in a tall cabinet and used random access magnetic tape drives (DECtape) for storing completed presentations. The graphics generator (Forox recorder) was capable of outputting 2,000 line resolution, suitable for 35mm and 72mm film and large sheet film positive using larger cassettes for recording. 4000 and 8000 line resolution was later achieved with duplex scanning and 4x scanning by modifying to the Forox recorder's settings menu. Subsequent models (100B,C,D,D+ and D+/GVP) replaced the knobs and dials with an on screen, text based menu system, a graphics tablet and a pen.
|
|
Disc recording is restricted to storing files playable on consumer appliances (films, music, etc.), relatively small volumes of data (e.g. a standard DVD holds 4.7 gigabytes, however, higher- capacity formats such as multi-layer Blu-ray Discs exist) for local use, and data for distribution, but only on a small scale; mass-producing large numbers of identical discs by pressing (replication) is cheaper and faster than individual recording (duplication). Optical discs are used to back up relatively small volumes of data, but backing up of entire hard drives, which typically contain many hundreds of gigabytes or even multiple terabytes, is less practical. Large backups are often instead made on external hard drives, as their price has dropped to a level making this viable; in professional environments magnetic tape drives are also used.
|
|
The primary improvements of the 709 over the previous 704 involved more magnetic core memory and apparently the first use of independent I/O channels. Whereas I/O on 704 is a programmed function of the central processor - data words are transferred to or from the I/O register, one at a time, using a "copy" instruction - the 709 uses the IBM-766 Data Synchronizer, which provides two independently "programmed" I/O channels. Up to three Data Synchronizers can be attached to a 709, each able to control up to 20 IBM 729 tape drives and an IBM 716 alphanumeric line printer, IBM 711 card-reader and 721 card punch. This allows six times as many I/O devices on 709, and allows I/O to proceed on multiple devices while program execution continues in parallel.
|
|
The general-purpose registers had an access time of one microsecond. LARC weighed about . The basic configuration had one Computer and LARC could be expanded to a multiprocessor with a second Computer. The Processor is an independent CPU (with a different instruction set from the Computers) and provides control for 12 to 24 magnetic drum storage units, four to forty UNISERVO II tape drives, two electronic page recorders (a 35mm film camera facing a cathode-ray tube), one or two high-speed printers, and a high- speed punched card reader. The LARC used core memory banks of 2500 words each, housed four banks per memory cabinet. The basic configuration had eight banks of core (two cabinets), 20,000 words. The memory could be expanded to a maximum of 39 banks of core (ten cabinets with one empty bank), 97,500 words.
|
|
As machines became more powerful the time to run programs diminished, and the time to hand off the equipment to the next user became large by comparison. Accounting for and paying for machine usage moved on from checking the wall clock to automatic logging by the computer. Run queues evolved from a literal queue of people at the door, to a heap of media on a jobs-waiting table, or batches of punch-cards stacked one on top of the other in the reader, until the machine itself was able to select and sequence which magnetic tape drives processed which tapes. Where program developers had originally had access to run their own jobs on the machine, they were supplanted by dedicated machine operators who looked after the machine and were less and less concerned with implementing tasks manually.
|
|
Wafadrive packaging Rotronics Wafadrive shown with two Wafa tapes, a blank 64 kB and software release tape Front and back of a Rotronics 64 kB Wafa tape The Rotronics Wafadrive was a continuous tape loop storage (like conventional magnetic tape but arranged in a loop) peripheral launched in late 1984 for the Sinclair ZX Spectrum 8-bit home computer, intended to compete with Sinclair's ZX Interface 1 and ZX Microdrive. The Wafadrive comprised two continuous loop "stringy floppy" tape drives, an RS-232 interface and Centronics parallel port. The drives could run at two speeds: High speed (for seeking) and low speed (for reading/writing, which was significantly slower than that of Microdrives). The cartridges (or "wafers"), the same as those used in Entrepo stringy floppy devices for other microcomputers, were physically larger than Microdrive cartridges.
|
|
Enhanced Small Disk Interface (ESDI) was a disk interface designed by Maxtor Corporation in the early 1980s to be a follow-on to the ST-412/506 interface. ESDI improved on ST-506 by moving certain parts that were traditionally kept on the controller (such as the data separator) into the drives themselves, and also generalizing the control bus such that more kinds of devices (such as removable disks and tape drives) could be connected. ESDI used the same cabling as ST-506 (one 34-pin common control cable, and a 20-pin data channel cable for each device), and thus could easily be retrofitted to ST-506 applications. ESDI was popular in the mid-to-late 1980s, when SCSI and IDE technologies were young and immature, and ST-506 was neither fast nor flexible enough.
|
|
Bruce Webster of BYTE reported a rumor in December 1985: "Supposedly, Apple will be releasing a Big Mac by the time this column sees print: said Mac will reportedly come with 1 megabyte of RAM ... the new 128K-byte ROM ... and a double-sided (800K bytes) disk drive, all in the standard Mac box". Introduced as the Macintosh Plus, it was the first Macintosh model to include a SCSI port, which launched the popularity of external SCSI devices for Macs, including hard disks, tape drives, CD-ROM drives, printers, Zip Drives, and even monitors. The SCSI implementation of the Plus was engineered shortly before the initial SCSI spec was finalized and, as such, is not 100% SCSI-compliant. SCSI ports remained standard equipment for all Macs until the introduction of the iMac in 1998, which replaced most of Apple's "legacy ports" with USB.
|
|
Seagate 20 MB HDD and Western Digital Controller for PC Hard disk drives for personal computers (PCs) were initially a rare and very expensive optional feature; systems typically had only the less expensive floppy disk drives or even cassette tape drives as both secondary storage and transport media. However by the late '80s, hard disk drives were standard on all but the cheapest PC and floppy disks were used almost solely as transport media. Most hard disk drives in the early 1980s were sold to PC end users by systems integrators such as the Corvus Disk System or the systems manufacturer such as the Apple ProFile. The IBM PC XT in 1983, included an internal standard 10 MB hard disk drive, and soon thereafter internal hard disk drives proliferated on personal computers, one popular type was the ST506/ST412 hard drive and MFM interface.
|
|
Manufacturers often specify the capacity of tapes using data compression techniques; compressibility varies for different data (commonly 2:1 to 8:1), and the specified capacity may not be attained for some types of real data. , tape drives capable of higher capacity were still being developed. In 2011, Fujifilm and IBM announced that they had been able to record 29.5 billion bits per square inch with magnetic tape media developed using the BaFe particles and nanotechnologies, allowing drives with true (uncompressed) tape capacity of 35 TB. The technology was not expected to be commercially available for at least a decade. In 2014, Sony and IBM announced that they had been able to record 148 gigabits per square inch with magnetic tape media developed using a new vacuum thin-film forming technology able to form extremely fine crystal particles, allowing true tape capacity of 185 TB.
|
|
International Timesharing Corporation (ITS) of Chaska, Minnesota sold timesharing services using CDC 3300s. (ITS later acquired another timesharing company that used CDC 3600s, before it, in turn, was acquired by United Computing Systems of Kansas City, Missouri.) California State University at Northridge had a dual 3170 that provided timesharing service to the California State University and College system. Many of the other campuses also had CDC 3150 machines for local batch operation. In 1970 CDC 3150s were installed at most campuses of the California State College system. San Jose State and LA State got CDC 3300s and served as regional data centers with (very flaky) data links to the other campuses. California State Polytechnic College (San Luis Obispo) and San Diego State University had IBM System/360s. The rest got 3150s. Typical configuration was 24K words of 24-bit core memory, four 7-track tape drives, drum printer, card reader, card punch, two 8MB disc drives (removable packs).
|
|
Historically, secondary storage in computer systems has been implemented primarily by using magnetic properties of the surface coatings applied to rotating platters (in hard disk drives and floppy disks) or linearly moving narrow strips of plastic film (in tape drives). Pairing such magnetic media with read/write heads allows data to be written by separately magnetizing small sections of the ferromagnetic coating, and read later by detecting the transitions in magnetization. For the data to be read or written, exact sections of the magnetic media need to pass under the read/write heads that flow closely to the media surface; as a result, reading or writing data imposes delays required for the positioning of magnetic media and heads, with the delays differing depending on the actual technology. An illustration of the write amplification phenomenon in flash- based storage devices Over time, the performance gap between the central processing units (CPUs) and electromechanical storage (hard disk drives and their RAID setups) widened, requiring advancements in the secondary storage technology.
|
|