|
RK05
Digital Equipment Corporation's RK05 is a disk drive whose removable disk pack can hold about 2.5 megabytes of data. Introduced 1972, it is similar to IBM's 1964-introduced 2310, and uses a disk pack similar to IBM's 2315 disk pack, although the latter only held 1 megabyte. An RK04 drive, which has half the capacity of an RK05, was also offered. Systems on which it can be used include DEC's PDP-8, PDP-11, and PDP-15. Overview The RK05 was a moving head magnetic disk drive manufactured by DEC. It stored approximately 2.5 MB on a 14", single-platter IBM-2315-style front-loading removable disk cartridge. The cartridge permitted users to have relatively unlimited off-line storage and to have very fast access to such data. The PDP systems to which it could be attached had numerous operating systems for each computer architecture, so by changing disk pack another operating system could also be booted. Although the 14-inch cartridge could not fit in a shirt pocket, unlike DEC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RK05
Digital Equipment Corporation's RK05 is a disk drive whose removable disk pack can hold about 2.5 megabytes of data. Introduced 1972, it is similar to IBM's 1964-introduced 2310, and uses a disk pack similar to IBM's 2315 disk pack, although the latter only held 1 megabyte. An RK04 drive, which has half the capacity of an RK05, was also offered. Systems on which it can be used include DEC's PDP-8, PDP-11, and PDP-15. Overview The RK05 was a moving head magnetic disk drive manufactured by DEC. It stored approximately 2.5 MB on a 14", single-platter IBM-2315-style front-loading removable disk cartridge. The cartridge permitted users to have relatively unlimited off-line storage and to have very fast access to such data. The PDP systems to which it could be attached had numerous operating systems for each computer architecture, so by changing disk pack another operating system could also be booted. Although the 14-inch cartridge could not fit in a shirt pocket, unlike DEC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diablo Data Systems
Diablo Data Systems was a division of Xerox created by the acquisition of Diablo Systems Inc. for US$29 million in 1972,Xerox Factbook 2003-2004 , p.43 a company which had been founded in 1969 by George E. Comstock, Charles L. Waggoner and others. The company was best known for the HyType I and HyType II typewriter-based s, the daisywheel printers, as well as removable hard disk drives that were used in the |
OS/8
OS/8 is the primary operating system used on the Digital Equipment Corporation's PDP-8 minicomputer. PDP-8 operating systems which precede OS/8 include: * R-L Monitor, also referred to as MS/8. * P?S/8, requiring only 4K of memory. * PDP-8 4K Disk Monitor System * PS/8 ("Programming System/8"), requiring 8K. This is what became OS/8 in 1971. Other/related DEC operating systems are OS/78, OS/278, and OS/12. The latter is a virtually identical version of OS/8, and runs on Digital's PDP-12 computer. Digital released OS/8 images for non-commercial purposes which can be emulated through SIMH. Overview OS/8 provides a simple operating environment that is commensurate in complexity and scale with the PDP-8 computers on which it ran. I/O is supported via a series of supplied drivers which uses polled (not interrupt-driven) techniques. The device drivers have to be cleverly written as they can occupy only one or two memory pages of 128 12-bit words, and have to be able to run in an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PDP-11
The PDP-11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC's most successful product lines. The PDP-11 is considered by some experts to be the most popular minicomputer. The PDP-11 included a number of innovative features in its instruction set and additional general-purpose registers that made it much easier to program than earlier models in the PDP series. Further, the innovative Unibus system allowed external devices to be easily interfaced to the system using direct memory access, opening the system to a wide variety of peripherals. The PDP-11 replaced the PDP-8 in many real-time computing applications, although both product lines lived in parallel for more than 10 years. The ease of programming of the PDP-11 made it very popular for general-purpose computing uses a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PDP-15
The PDP-15 was the fifth and last of the 18-bit minicomputers produced by Digital Equipment Corporation. The PDP-1 was first delivered in December 1959 and the first PDP-15 was delivered in February 1970. More than 400 of these successors to the PDP-9 (and 9/L) were ordered within the first eight months. In addition to operating systems, the PDP-15 had compilers for Fortran and ALGOL. History The 18-bit PDP systems preceding the PDP-15 were named PDP-1, PDP-4, PDP-7 & PDP-9. The last PDP-15 was produced in 1979. Hardware The PDP-15 was DEC's only 18-bit machine constructed from TTL integrated circuits rather than discrete transistors, and, like every DEC 18-bit system could be equipped with: * an optional X-Y (point-plot or vector graphics) display. * a hardware floating point option, with a 10x speedup, was offered. * up to 128Kwords of core main memory Models The PDP-15 models offered by DEC were: * PDP-15/10: a 4K-word paper-tape based system * PDP-15/20: 8K, added DEC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Equipment Corporation
Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until forced to resign in 1992, after the company had gone into precipitous decline. The company produced many different product lines over its history. It is best known for the work in the minicomputer market starting in the mid-1960s. The company produced a series of machines known as the PDP line, with the PDP-8 and PDP-11 being among the most successful minis in history. Their success was only surpassed by another DEC product, the late-1970s VAX "supermini" systems that were designed to replace the PDP-11. Although a number of competitors had successfully competed with Digital through the 1970s, the VAX cemented the company's place as a leading vendor in the computer space. As microcomputers improved in the late 1980s, especially w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unibus
The Unibus was the earliest of several computer bus and backplane designs used with PDP-11 and early VAX systems manufactured by the Digital Equipment Corporation (DEC) of Maynard, Massachusetts. The Unibus was developed around 1969 by Gordon Bell and student Harold McFarland while at Carnegie Mellon University. The name refers to the unified nature of the bus; Unibus was used both as a system bus allowing the central processing unit to communicate with main memory, as well as a peripheral bus, allowing peripherals to send and receive data. Unifying these formerly separate busses allowed external devices to easily perform direct memory access (DMA) and made the construction of device drivers easier as control and data exchange was all handled through memory-mapped I/O. Unibus was physically large, which led to the introduction of Q-bus, which multiplexed some signals to reduce pin count. Higher performance PDP systems used Fastbus, essentially two Unibusses in one. The sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daisy Chain (electrical Engineering)
In electrical and electronic engineering, a daisy chain is a wiring scheme in which multiple devices are wired together in sequence or in a ring, similar to a garland of daisy flowers. Daisy chains may be used for power, analog signals, digital data, or a combination thereof. The term ''daisy chain'' may refer either to large scale devices connected in series, such as a series of power strips plugged into each other to form a single long line of strips, or to the wiring patterns embedded inside of devices. Other examples of devices which can be used to form daisy chains are those based on Universal Serial Bus (USB), FireWire, Thunderbolt and Ethernet cables. Signal transmission For analog signals, connections usually consist of a simple electrical bus and, especially in the case of a chain of many devices, may require the use of one or more repeaters or amplifiers within the chain to counteract attenuation (the natural loss of energy in such a system). Digital ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xerox
Xerox Holdings Corporation (; also known simply as Xerox) is an American corporation that sells print and electronic document, digital document products and services in more than 160 countries. Xerox is headquartered in Norwalk, Connecticut (having moved from Stamford, Connecticut, in October 2007), though it is incorporated in New York (state), New York with its largest population of employees based around Rochester, New York, the area in which the company was founded. The company purchased Affiliated Computer Services for $6.4 billion in early 2010. As a large developed company, it is consistently placed in the list of Fortune 500 companies. On December 31, 2016, Xerox separated its business process service operations, essentially those operations acquired with the purchase of Affiliated Computer Services, into a new publicly traded company, Conduent. Xerox focuses on its document technology and document outsourcing business, and traded on the NYSE from 1961 to 2021, and the N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferrite (magnet)
A ferrite is a ceramic material made by mixing and firing large proportions of iron(III) oxide (Fe2O3, rust) blended with small proportions of one or more additional metallic elements, such as strontium, barium, manganese, nickel, and zinc. They are ferrimagnetic, meaning they can be magnetized or attracted to a magnet. Unlike other ferromagnetic materials, most ferrites are not electrically conductive, making them useful in applications like magnetic cores for transformers to suppress eddy currents. Ferrites can be divided into two families based on their resistance to being demagnetized (magnetic coercivity). Hard ferrites have high coercivity, so are difficult to demagnetize. They are used to make permanent magnets for applications such as refrigerator magnets, loudspeakers, and small electric motors. Soft ferrites have low coercivity, so they easily change their magnetization and act as conductors of magnetic fields. They are used in the electronics industry to make efficien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head Crash
A head crash is a hard-disk failure that occurs when a read–write head of a hard disk drive makes contact with its rotating platter, slashing its surface and permanently damaging its magnetic media. It is most often caused by a sudden severe motion of the disk, for example the jolt caused by dropping a laptop to the ground while it is operating or physically shocking a computer. Head details A head normally rides on a thin film of moving air entrapped at the surface of its platter (some drives manufactured by Conner Peripherals in the mid-1990s used a thin liquid layer instead). The distance between the head and platter is called the flying height. The topmost layer of the platter is made of a Teflon-like material that acts like a lubricant. Underneath is a layer of sputtered carbon. These two layers protect the magnetic layer (data storage area) from most accidental touches of the read-write head. The disk read-and-write head is made using thin film techniques that in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HEPA
HEPA (, high-efficiency particulate air) filter, also known as high-efficiency particulate absorbing filter and high-efficiency particulate arrestance filter, is an efficiency standard of air filters. Filters meeting the HEPA standard must satisfy certain levels of efficiency. Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (ISO, European Standard) or 99.97% (ASME, U.S. DOE) of particles whose diameter is equal to 0.3 μm, with the filtration efficiency increasing for particle diameters both less than and greater than 0.3 μm. HEPA filters capture pollen, dirt, dust, moisture, bacteria (0.2-2.0 μm), virus (0.02-0.3 μm), and submicron liquid aerosol (0.02-0.5 μm). Some microorganisms, for example, ''Aspergillus niger'', '' Penicillium citrinum'', '' Staphylococcus epidermidis'', and ''Bacillus subtilis'' are captured by HEPA filters with photocatalytic oxidation (PCO). A HEPA filt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> PDP-11")
.jpg "Click for more on -> PDP-15")
