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Scancode
A scancode (or scan code) is the data that most computer keyboards send to a computer to report which keys have been pressed. A number, or sequence of numbers, is assigned to each key on the keyboard. Variants Mapping key positions by row and column requires less complex computer hardware; therefore, in the past, using software or firmware to translate the scancodes to text characters was less expensive than wiring the keyboard by text character. This cost difference is not as profound as it used to be. However, many types of computers still use their traditional scancodes to maintain backward compatibility. Some keyboard standards include a scancode for each key being pressed and a different one for each key being released. In addition, many keyboard standards (for example, IBM PC compatible standards) allow the keyboard itself to generate " typematic" repeating keys by having the keyboard itself generate the pressed-key scancode repeatedly while the key is held down, wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keyboard Layout
A keyboard layout is any specific physical, visual or functional arrangement of the keys, legends, or key-meaning associations (respectively) of a computer keyboard, mobile phone, or other computer-controlled typographic keyboard. is the actual positioning of keys on a keyboard. is the arrangement of the legends (labels, markings, engravings) that appear on those keys. is the arrangement of the key-meaning association or keyboard mapping, determined in software, of all the keys of a keyboard; it is this (rather than the legends) that determines the actual response to a key press. Modern computer keyboards are designed to send a scancode to the operating system (OS) when a key is pressed or released: this code reports only the key's row and column, not the specific character engraved on that key. The OS converts the scancode into a specific binary character code using a "scancode to character" conversion table, called the keyboard mapping table. This means that a physical key ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Keyboard
A computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input method for computers since the 1970s, supplemented by the computer mouse since the 1980s. Keyboard keys (buttons) typically have a set of characters engraved or printed on them, and each press of a key typically corresponds to a single written symbol. However, producing some symbols may require pressing and holding several keys simultaneously or in sequence. While most keys produce characters (letters, numbers or symbols), other keys (such as the escape key) can prompt the computer to execute system commands. In a modern computer, the interpretation of key presses is generally left to the software: the information sent to the computer, the scan code, tells it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Keyboards
A computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input method for computers since the 1970s, supplemented by the computer mouse since the 1980s. Keyboard keys (buttons) typically have a set of characters engraved or printed on them, and each press of a key typically corresponds to a single written symbol. However, producing some symbols may require pressing and holding several keys simultaneously or in sequence. While most keys produce characters (letters, numbers or symbols), other keys (such as the escape key) can prompt the computer to execute system commands. In a modern computer, the interpretation of key presses is generally left to the software: the information sent to the computer, the scan code, tells it only whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 3270 PC
The IBM 3270 PC (IBM System Unit 5271), released in October 1983, is an IBM PC XT containing additional hardware that, in combination with software, can emulate the behaviour of an IBM 3270 terminal. It can therefore be used both as a standalone computer, and as a terminal to a mainframe. IBM later released the ''3270 AT'' (IBM System Unit 5273), which is a similar design based on the IBM PC AT. They also released high-end graphics versions of the 3270 PC in both XT and AT variants. The XT-based versions are called 3270 PC/G and 3270 PC/GX and they use a different System Unit 5371, while their AT counterparts (PC AT/G and PC AT/GX) have System Unit 5373. Technology The additional hardware occupies nearly all the free expansion slots in the computer. It includes a video card which occupies 1-3 ISA slots (depending on what level of graphics support is required), and supports CGA and MDA video modes. The display resolution is 720×350, either on the matching 14-inch color mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motherboard
A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expandable systems. It holds and allows communication between many of the crucial electronic components of a system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals. Unlike a backplane, a motherboard usually contains significant sub-systems, such as the central processor, the chipset's input/output and memory controllers, interface connectors, and other components integrated for general use. ''Motherboard'' means specifically a PCB with expansion capabilities. As the name suggests, this board is often referred to as the "mother" of all components attached to it, which often include peripherals, interface cards, and daughterboards: sound cards, video cards, network cards, host bus adapters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meta Key
The Meta key is a modifier key on certain keyboards. It first appeared on the Stanford Artificial Intelligence Lab (SAIL) keyboard in 1970. History The Meta key first appeared on the Stanford Artificial Intelligence Lab (SAIL) keyboard in 1970 and successors such as the Knight keyboard, space-cadet keyboard, MIT Lisp machine, Symbolics keyboards, and on Sun Microsystems keyboards (where it is marked with a black diamond "◆"). Use Generally, the Meta key worked similar to Macintosh's Command key, in that when held down it modified letters and symbols into immediate commands (shortcuts). On these keyboards the Control key was placed closest to the space bar, then the Meta key outside Control. The space-cadet keyboard added the Super key outside Meta, and the Hyper key outside that. All these keys produced shortcuts (24 of them for every letter), but the Control ones were easiest to type and most popular, and the Meta ones second-easiest and thus second most popular. Ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dead Key
A dead key is a special kind of modifier key on a mechanical typewriter, or computer keyboard, that is typically used to attach a specific diacritic to a base letter. The dead key does not generate a (complete) character by itself, but modifies the character generated by the key struck immediately after. Thus, a dedicated key is not needed for each possible combination of a diacritic and a letter, but rather only one dead key for each diacritic is needed, in addition to the normal base letter keys. For example, if a keyboard has a dead key for the ''grave accent'' (`), the French character ''à'' can be generated by first pressing and then , whereas ''è'' can be generated by first pressing and then . Usually, the diacritic itself can be generated as an isolated character by pressing the dead key followed by ''space''; so a plain grave accent can be typed by pressing and then . Mechanical typewriters The dead key is mechanical in origin, and "dead" means without movement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft
Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washington, United States. Its best-known software products are the Windows line of operating systems, the Microsoft Office suite, and the Internet Explorer and Edge web browsers. Its flagship hardware products are the Xbox video game consoles and the Microsoft Surface lineup of touchscreen personal computers. Microsoft ranked No. 21 in the 2020 Fortune 500 rankings of the largest United States corporations by total revenue; it was the world's largest software maker by revenue as of 2019. It is one of the Big Five American information technology companies, alongside Alphabet, Amazon, Apple, and Meta. Microsoft was founded by Bill Gates and Paul Allen on April 4, 1975, to develop and sell BASIC interpreters for the Altair 8800. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Universal Serial Bus
Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply (interfacing) between computers, peripherals and other computers. A broad variety of USB hardware exists, including 14 different connector types, of which USB-C is the most recent and the only one not currently deprecated. First released in 1996, the USB standards are maintained by the USB Implementers Forum (USB-IF). The four generations of USB are: USB 1.''x'', USB 2.0, USB 3.''x'', and USB4. Overview USB was designed to standardize the connection of peripherals to personal computers, both to communicate with and to supply electric power. It has largely replaced interfaces such as serial ports and parallel ports, and has become commonplace on a wide range of devices. Examples of peripherals that are connected via USB include computer keyboards and mice, video cameras, printers, portable media players, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Windows Key
The Windows logo key (also known as Windows-, win-, start-, logo-, flag-, or super-key) is a keyboard key which was originally introduced on the Microsoft Natural keyboard in 1994. This key became a standard key on PC keyboards. In Windows tapping the key brings up the start menu. performs the same function, in case the keyboard lacks this key. History and usage Historically, the addition of two Windows keys and a menu key marked the change from the 101/102-key to 104/105-key layout for PC keyboards. Compared to the former layout, a Windows key was placed between the left and the left and another Windows key and the menu key were placed between the right (or ) and the right key. The key is predated by the key on Apple computers in the 1980s, and before that by the (or ) key on Lisp/Unix workstation computers in the 1970s. In laptop and other compact keyboards it is common to have just one Windows key (usually on the left). On Microsoft's Entertainment Desktop set ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Numeric Keypad
A numeric keypad, number pad, numpad, or ten key, is the palm-sized, usually-17-key section of a standard computer keyboard, usually on the far right. It provides calculator-style efficiency for entering numbers. The idea of a 10-key number pad cluster was originally introduced by Tadao Kashio, the developer of Casio electronic calculators. The numpad's keys are digits to , (addition), (subtraction), (multiplication) and ( division) symbols, (decimal point), , and keys.numeric keypad' at FOLDOC Laptop keyboards often do not have a numpad, but may provide numpad input by holding a modifier key (typically labelled ) and operating keys on the standard keyboard. Particularly large laptops (typically those with a 15.6 inch screen or larger) may have space for a real numpad, and many companies sell separate numpads which connect to the host laptop by a USB connection (many of these also add an additional spacebar off to the side of the zero where the thumb is loc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enter Key
On computer keyboards, the enter key and return key are two closely related keys with overlapping and distinct functions dependent on operating system and application. Functions The return key has its origins in two typewriter functions: carriage return, which would reset the carriage to the beginning of the line of text, and line feed, which would advance the paper one line downward. These were often combined into a single return key, a convention that continues in modern computer word processing to insert a paragraph break (¶). The enter key is a computer innovation, which in most cases causes a command line, window form, or dialog box to operate its default function. This is typically to finish an "entry" and begin the desired process, and is usually an alternative to clicking an OK button. Additionally, it can act as the ''equal to'' button in calculator programs. On modern computers both keys generally have all the functions of the other, allowing for either key to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
