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Univac Uniscope
Uniscope was a class of computer terminals made by Sperry Rand Corporation, Univac Division, and successors since 1964 that were normally used to communicate with Univac mainframes. As such, it was the successor to various models of Teletype Corporation, Teletype. Due to the text color on the original models, these terminals are informally known as ''green screen terminals''. Unlike Teletype Corporation, Teletype terminals, the Uniscope minimizes the number of I/O interrupts required by accepting large blocks of data, and uses a high speed proprietary communications interface, using coaxial cable and hardware devices known as Channel I/O#Types of channels, multiplexors. A Uniscope operator awaits a prompt from the remote mainframe. The prompt indicates that the mainframe is ready to receive input. The operator enters data, offline from the mainframe, and then presses the Transmit button. The terminal locks the keyboard and sends to the mainframe what the operator entered. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Letter-quality Printer
A letter-quality printer was a form of computer impact printer that was able to print with the quality typically expected from a business typewriter such as an IBM Selectric. A letter-quality printer operates in much the same fashion as a typewriter. A metal or plastic printwheel embossed with letters, numbers, or symbols strikes an inked ribbon, depositing the ink (or carbon, if an expensive single-strike ribbon was installed) on the page and thus printing a character. Over time, several different technologies were developed including automating ordinary typebar typewriter mechanisms (such as the Friden Flexowriter), daisy wheel printers (dating from a 1939 patent, but brought to life in the 1970s by Diablo engineer David S. Lee) where the type is moulded around the edge of a wheel, and "golf ball" (the popular informal name for "typeball", as used in the IBM Selectric typewriter) printers where the type is distributed over the face of a globe-shaped printhead (including aut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Computing Hardware
The history of computing hardware spans the developments from early devices used for simple calculations to today's complex computers, encompassing advancements in both analog and digital technology. The first aids to computation were purely mechanical devices which required the operator to set up the initial values of an elementary arithmetic operation, then manipulate the device to obtain the result. In later stages, computing devices began representing numbers in continuous forms, such as by distance along a scale, rotation of a shaft, or a specific voltage level. Numbers could also be represented in the form of digits, automatically manipulated by a mechanism. Although this approach generally required more complex mechanisms, it greatly increased the precision of results. The development of transistor technology, followed by the invention of integrated circuit chips, led to revolutionary breakthroughs. Transistor-based computers and, later, integrated circuit-based computers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of UNIVAC Products
This is a list of UNIVAC products. It ends in 1986, the year that Sperry Corporation merged with Burroughs Corporation to form Unisys as a result of a hostile takeover bid launched by Burrough's CEO W. Michael Blumenthal. The Remington Rand years (1950 to 1955) Calculating devices * UNIVAC 40 * UNIVAC 60 * UNIVAC 120 Computer systems *UNIVAC I *UNIVAC 1101 * UNIVAC 1102 * UNIVAC 1103 * UNIVAC 1104 Peripherals Storage * UNISERVO tape drive Display and print * UNIVAC High speed printer 600 line/min printer Offline tape handling units * UNIPRINTER 10 char/s printer with tape drive * UNITYPER keyboard with tape drive *UNIVAC Tape to Card converter card punch with tape drive * UNIVAC Card to Tape converter card reader with tape drive * UNIVAC Paper Tape to Tape converter paper tape reader with tape drive The Sperry Rand years (1955 to 1978) Calculating devices * UNIVAC 1004 * UNIVAC 1005 Computer systems Embedded systems *AN/USQ-17 – the Naval Tactical Data Syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emulator
In computing, an emulator is Computer hardware, hardware or software that enables one computer system (called the ''host'') to behave like another computer system (called the ''guest''). An emulator typically enables the host system to run software or use peripheral devices designed for the guest system. Emulation refers to the ability of a computer program in an electronic device to emulate (or imitate) another program or device. Many printer (computing), printers, for example, are designed to emulate Hewlett-Packard, HP LaserJet printers because a significant amount of software is written specifically for HP models. If a non-HP printer emulates an HP printer, any software designed for an actual HP printer will also function on the non-HP device, producing equivalent print results. Since at least the 1990s, many video game enthusiasts and hobbyists have used emulators to play classic arcade games from the 1980s using the games' original 1980s machine code and data, which is in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enhanced Graphics Adapter
The Enhanced Graphics Adapter (EGA) is an IBM PC compatible, IBM PC Video card, graphics adapter and ''de facto'' computer display standard from 1984 that superseded the Color Graphics Adapter, CGA standard introduced with the IBM Personal Computer, original IBM PC, and was itself superseded by the Video Graphics Array, VGA standard in 1987. In addition to the original EGA card manufactured by IBM, many compatible third-party cards were manufactured, and EGA graphics modes continued to be supported by VGA and later standards. History EGA was introduced in October 1984 by IBM,High-Resolution Standard Is Latest Step in DOS Graphics Evolution, ''InfoWorld'', June 26, 1989, p. 48.News Briefs, Big Blue Turns Colors, ''InfoWorld'', October 8, 1984. shortly after its new IBM Personal Computer AT, PC/AT. The EGA could be installed in previously released IBM PCs, but required a Read-only memory, ROM upgrade on the Motherboard, mainboard. Chips and Technologies' first product, announced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polling (computer Science)
Polling, or interrogation, refers to actively sampling the status of an external device by a client program as a synchronous activity. Polling is most often used in terms of input/output (), and is also referred to as polled or software-driven . A good example of hardware implementation is a watchdog timer. Description Polling is the process where the computer or controlling device waits for an external device to check for its readiness or state, often with low-level hardware. For example, when a printer is connected via a parallel port, the computer waits until the printer has received the next character. These processes can be as minute as only reading one bit. This is sometimes used synonymously with ' busy-wait' polling. In this situation, when an operation is required, the computer does nothing other than check the status of the device until it is ready, at which point the device is accessed. In other words, the computer waits until the device is ready. Polling also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Printer
A printer is a peripheral machine which makes a durable representation of graphics or text, usually on paper. While most output is human-readable, bar code printers are an example of an expanded use for printers. Different types of printers include 3D printers, inkjet printers, laser printers, and thermal printers. History The first computer printer designed was a mechanically driven apparatus by Charles Babbage for his difference engine in the 19th century; however, his mechanical printer design was not built until 2000. He also had plans for a curve plotter, which would have been the first computer graphics printer if it was built. The first patented printing mechanism for applying a marking medium to a recording medium or more particularly an electrostatic inking apparatus and a method for electrostatically depositing ink on controlled areas of a receiving medium, was in 1962 by C. R. Winston, Teletype Corporation, using continuous inkjet printing. The ink was a red sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Terminal
A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. Most early computers only had a front panel to input or display bits and had to be connected to a terminal to print or input text through a keyboard. Teleprinters were used as early-day hard-copy terminals and predated the use of a computer screen by decades. The computer would typically transmit a line of data which would be printed on paper, and accept a line of data from a keyboard over a serial or other interface. Starting in the mid-1970s with microcomputers such as the Sphere 1, Sol-20, and Apple I, display circuitry and keyboards began to be integrated into personal and workstation computer systems, with the computer handling character generation and outputting to a CRT display such as a computer monitor or, sometimes, a consumer TV, but most larger computers continued to require terminal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiplexer
In electronics, a multiplexer (or mux; spelled sometimes as multiplexor), also known as a data selector, is a device that selects between several Analog signal, analog or Digital signal (electronics), digital input signals and forwards the selected input to a single output line. The selection is directed by a separate set of digital inputs known as select lines. A multiplexer of 2^n inputs has n select lines, which are used to select which input line to send to the output. A multiplexer makes it possible for several input signals to share one device or resource, for example, one analog-to-digital converter or one communications transmission medium, instead of having one device per input signal. Multiplexers can also be used to implement Boolean algebra, Boolean functions of multiple variables. Conversely, a demultiplexer (or demux) is a device that takes a single input signal and selectively forwards it to one of several output lines. A multiplexer is often used with a complem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Protocol
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any variation of a physical quantity. The protocol defines the rules, syntax, semantics (computer science), semantics, and synchronization of communication and possible Error detection and correction, error recovery methods. Protocols may be implemented by Computer hardware, hardware, software, or a combination of both. Communicating systems use well-defined formats for exchanging various messages. Each message has an exact meaning intended to elicit a response from a range of possible responses predetermined for that particular situation. The specified behavior is typically independent of how it is to be Implementation, implemented. Communication protocols have to be agreed upon by the parties involved. To reach an agreement, a protocol may be developed into a technical standard. A programming language describes the same for computations, so there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Synchronous Communications
Binary Synchronous Communication (BSC or Bisync) is an IBM character-oriented, half-duplex link protocol, announced in 1967 after the introduction of System/360. It replaced the synchronous transmit-receive (STR) protocol used with second generation computers. The intent was that common link management rules could be used with three different character encodings for messages. Six-bit Transcode looked backward to older systems; USASCII with 128 characters and EBCDIC with 256 characters looked forward. Transcode disappeared very quickly but the EBCDIC and USASCII dialects of Bisync continued in use. At one time Bisync was the most widely used communications protocol and is still in limited use in 2013. Framing Bisync differs from protocols that succeeded it in the complexity of message framing. Later protocols use a single framing scheme for all messages sent by the protocol. HDLC, Digital Data Communications Message Protocol (DDCMP), Point-to-Point Protocol (PPP), etc. e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
