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ISO 6429
The C0 and C1 control code or control character sets define control codes for use in text by computer systems that use ASCII and derivatives of ASCII. The codes represent additional information about the text, such as the position of a cursor, an instruction to start a new line, or a message that the text has been received. C0 codes are the range 00 HEX–1FHEX and the default C0 set was originally defined in ISO 646 (ASCII). C1 codes are the range 80HEX–9FHEX and the default C1 set was originally defined in ECMA-48 (harmonized later with ISO 6429). The ISO/IEC 2022 system of specifying control and graphic characters allows other C0 and C1 sets to be available for specialized applications, but they are rarely used. C0 controls ASCII defined 32 control characters, plus a necessary extra character for the DEL character, 7FHEX or 01111111BIN (needed to punch out all the holes on a paper tape and erase it). This large number of codes was desirable at the time, as multi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Character
In computing and telecommunication, a control Character (computing), character or non-printing character (NPC) is a code point (a number) in a character encoding, character set, that does not represent a written symbol. They are used as in-band signaling to cause effects other than the addition of a symbol to the text. All other characters are mainly printing, printable, or graphic characters, except perhaps for the "space (punctuation), space" character (see ASCII printable characters). History Prosigns for Morse code, Procedural signs in Morse code are a form of control character. A form of control characters were introduced in the 1870 Baudot code: NUL and DEL. The 1901 Murray code added the carriage return (CR) and line feed (LF), and other versions of the Baudot code included other control characters. The bell character (BEL), which rang a bell to alert operators, was also an early Teleprinter, teletype control character. Control characters have also been called "format ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
End-of-text Character
The End-of-Text character (ETX) is a control character used to inform the receiving computer that the end of a record has been reached. This may or may not be an indication that all of the data in a record have been received. In ASCII and in EBCDIC, ETX is code point 0x03, often displayed as {{mono, ^C). It is often used as a "break" character (Control-C) to interrupt a program or process. In TOPS-20, it was used to gain the system's attention before logging in. It is often used in conjunction with Start of Text (STX) and Data Link Escape (DLE), e.g., to distinguish frames in the Data link layer. mIRC uses ETX as the color character escape character. See also * C0 and C1 control codes The C0 and C1 control code or control character sets define control codes for use in text by computer systems that use ASCII and derivatives of ASCII. The codes represent additional information about the text, such as the position of a cursor, ... Control characters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO/IEC 8859
ISO/IEC 8859 is a joint ISO and IEC series of standards for 8-bit character encodings. The series of standards consists of numbered parts, such as ISO/IEC 8859-1, ISO/IEC 8859-2, etc. There are 15 parts, excluding the abandoned ISO/IEC 8859-12. The ISO working group maintaining this series of standards has been disbanded. ISO/IEC 8859 parts 1, 2, 3, and 4 were originally Ecma International standard ECMA-94. Introduction While the bit patterns of the 95 printable ASCII characters are sufficient to exchange information in modern English, most other languages that use Latin alphabets need additional symbols not covered by ASCII. ISO/IEC 8859 sought to remedy this problem by utilizing the eighth bit in an 8-bit byte to allow positions for another 96 printable characters. Early encodings were limited to 7 bits because of restrictions of some data transmission protocols, and partially for historical reasons. However, more characters were needed than could fit in a single 8-bit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backspace
Backspace () is the keyboard key that originally pushed the typewriter carriage one position backwards and in modern computer systems moves the display cursor one position backwards,"Backwards" means to the left for left-to-right languages. deletes the character at that position, and shifts back the text after that position by one position. Typewriter In someMany typewriters don't advance accent characters, so that no backspace is needed. However, it is still used e.g. for combining "o" with "/". typewriters, a typist would, for example, type a lowercase letter A with acute accent (á) by typing a lowercase letter A, backspace, and then the acute accent key. This technique (also known as overstrike) is the basis for such spacing modifiers in computer character sets such as the ASCII caret (^, for the circumflex accent). Backspace composition no longer works with typical modern digital displays or typesetting systems.There is no reason why a digital display or typesetting system cou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inverse Video
Reverse video (or invert video or inverse video or reverse screen) is a computer display technique whereby the background and text color values are inverted. On older computers, displays were usually designed to display text on a black background by default (computer science), default. For emphasis, the color scheme was swapped to bright background with dark text. Nowadays the two tend to be switched, since most computers today default to white as a background color. The opposite of reverse video is known as ''true video''. Video is usually reversed by inverting the brightness values of the pixels of the involved region of the display. If there are 256 levels of brightness, encoded as 0 to 255, the 255 value becomes 0 and vice versa. A value of 1 becomes 254, 2 of 253, and so on: ''n'' is swapped for ''r'' - ''n'', for ''r'' levels of brightness. This is occasionally called a ones' complement. If the source image is of middle brightness, reverse video can be difficult to see, 127 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell (instrument)
A bell is a directly struck idiophone percussion instrument. Most bells have the shape of a hollow cup that when struck vibrates in a single strong strike tone, with its sides forming an efficient resonator. The strike may be made by an internal "clapper" or "uvula", an external hammer, or—in small bells—by a small loose sphere enclosed within the body of the bell (jingle bell). Bells are usually cast from bell metal (a type of bronze) for its resonant properties, but can also be made from other hard materials. This depends on the function. Some small bells such as ornamental bells or cowbells can be made from cast or pressed metal, glass or ceramic, but large bells such as a church, clock and tower bells are normally cast from bell metal. Bells intended to be heard over a wide area can range from a single bell hung in a turret or bell-gable, to a musical ensemble such as an English ring of bells, a carillon or a Russian zvon which are tuned to a common scale and instal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell Character
A bell code (sometimes bell character) is a device control code originally sent to ring a small electromechanical bell on tickers and other teleprinters and teletypewriters to alert operators at the other end of the line, often of an incoming message. Though tickers punched the bell codes into their tapes, printers generally do not print a character when the bell code is received. Bell codes are usually represented by the label "BEL". They have been used since 1870 (initially in Baudot code). To maintain backward compatibility, video display terminals (VDTs) that replaced teletypewriters included speakers or buzzers to perform the same function, as did the personal computers that followed. Modern terminal emulators often integrate the warnings to the desktop environment (e.g., the macOS Terminal will play the system warning sound) and also often offer a silent ''visual bell'' feature that flashes the terminal window briefly. Representations In ASCII and Unicode the character w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Pictures
Control Pictures is a Unicode block containing characters for graphically representing the C0 control codes, and other control characters. Its block name in Unicode 1.0 was Pictures for Control Codes. Block History The following Unicode-related documents record the purpose and process of defining specific characters in the Control Pictures block: See also * ISO 2047 ISO 2047 (Information processing – Graphical representations for the control characters of the 7-bit coded character set) is a standard for graphical representation of the control characters for debugging purposes, such as may be found in the ... References {{reflist Unicode blocks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perl
Perl is a family of two high-level, general-purpose, interpreted, dynamic programming languages. "Perl" refers to Perl 5, but from 2000 to 2019 it also referred to its redesigned "sister language", Perl 6, before the latter's name was officially changed to Raku in October 2019. Though Perl is not officially an acronym, there are various backronyms in use, including "Practical Extraction and Reporting Language". Perl was developed by Larry Wall in 1987 as a general-purpose Unix scripting language to make report processing easier. Since then, it has undergone many changes and revisions. Raku, which began as a redesign of Perl 5 in 2000, eventually evolved into a separate language. Both languages continue to be developed independently by different development teams and liberally borrow ideas from each other. The Perl languages borrow features from other programming languages including C, sh, AWK, and sed; They provide text processing facilities without the arbitrary data-le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emoji
An emoji ( ; plural emoji or emojis) is a pictogram, logogram, ideogram or smiley embedded in text and used in electronic messages and web pages. The primary function of emoji is to fill in emotional cues otherwise missing from typed conversation. Examples of emoji are 😂, 😃, 🧘🏻♂️, 🌍, 🌦️, 🍞, 🚗, 📞, 🎉, ❤️, 🍆, 🍑 and 🏁. Emoji exist in various genres, including facial expressions, common objects, places and types of weather, and animals. They are much like emoticons, except emoji are pictures rather than typographic approximations; the term "emoji" in the strict sense refers to such pictures which can be represented as character encoding, encoded characters, but it is sometimes applied to Sticker (messaging), messaging stickers by extension. Originally meaning pictograph, the word ''emoji'' comes from Japanese + ; the resemblance to the English words ''emotion'' and ''emoticon'' is False cognate, purely coincidental. The I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acknowledge Character
In data networking, telecommunications, and computer buses, an acknowledgment (ACK) is a signal that is passed between communicating processes, computers, or devices to signify acknowledgment, or receipt of message, as part of a communications protocol. The negative-acknowledgement (NAK or NACK) is a signal that is sent to reject a previously received message or to indicate some kind of error. Acknowledgments and negative acknowledgments inform a sender of the receiver's state so that it can adjust its own state accordingly. Many protocols contain checksums to verify the integrity of the payload and header. Checksums are used to detect data corruption. If a message is received with an invalid checksum (that is, the data received would have a different checksum than the message had), the receiver can know that some information was corrupted. Most often, when checksums are employed, a corrupted message received will either not be served an ACK signal, or will be served a NAK sig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enquiry Character
In computer communications, enquiry is a transmission-control character that requests a response from the receiving station with which a connection has been set up. It represents a signal intended to trigger a response at the receiving end, to see whether it is still present. The response, an answer-back code to the terminal that transmitted the WRU (who are you) signal, may include station identification, the type of equipment in service, and the status of the remote station. Some teleprinters had a "programmable" drum, which could hold a 20- or 22-character message. The message was encoded on the drum by breaking tabs off the drum. This sequence could be transmitted upon receipt of an enquiry signal, if enabled, or by pressing the "Here is" key on the keyboard. The 5-bit ITA2 has an enquiry character, as do the later ASCII and EBCDIC. In the 1960s, DEC routinely disabled the answerback feature on Teletype Model 33 terminals because it interfered with the use of the pape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
