EBCDIC

IBM used the terms binary-coded decimal and BCD for six-bit alphameric codes that represented numbers, upper-case letters and special characters. Some variation of BCD was used in most early IBM computers, including the IBM 1620, IBM 1400 series and non-Decimal Architecture members of the IBM 700/7000 series. With the introduction of System/360, IBM replaced BCD with 8-bit EBCDIC. Bit positions in BCD were usually labeled B, A, 8, 4, 2 and 1. For encoding digits, B and A were z ...

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Binary-coded decimal, Binary-coded decimal - Basics, Binary-coded decimal - BCD in electronics, Binary-coded decimal - Higher-density encoding, Binary-coded decimal - IBM and BCD, Binary-coded decimal - Background, Binary-coded decimal - Legal history, Binary-coded decimal - Comparison with pure binary, Binary-coded decimal - Advantages, Binary-coded decimal - Disadvantages

Read more here: » Binary-coded decimal: Encyclopedia II - Binary-coded decimal - IBM and BCD

One starts with a non-empty finite set Σ called an alphabet. Elements of this alphabet are called characters. A string (or word) over Σ is any finite sequence of characters from Σ. Infinite sequences of characters are not allowed in this definition. A particularly important string is the sequence of no characters, called the empty string. The empty string is often denoted ε or λ. For example, if Σ = {0, 1}, strings over Σ are of the form

In English, the letter A by itself usually denotes the lax open front unrounded vowel (IPA /æ/) as in pad, the open back unrounded vowel (IPA /ɑ/) as in father, or, in concert with a later e, the diphthong /eɪ/ (though the actual pronunciation depends on the dialect) as in ace, due to effects of the Great vowel shift. In most other languages that use the Latin alphabet, the letter A denotes either an open back unrounded vowel (IPA /ɑ/), or an open central ...

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A, A - A, A - History, A - Usage, A - Alternative representations, A - Computing, A - Meanings for A

Read more here: » A: Encyclopedia II - A - Usage

In the NATO phonetic alphabet the letter A is Alfa (which may also be spelled Alpha in English-only environments). In international Morse code the letter A is DitDah: · - In Braille the letter A is represented as ⠁ (in Unicode), the dot pattern: A - Computing. In Unicode the capital A is codepoint U+0041 and the lowercase a is U+0061. In Hex, A is the character used to represent decimal 10, or in binary, 01010 The ASCII code for capital A is 65 and for lowercase a is 97; or ...

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A, A - A, A - History, A - Usage, A - Alternative representations, A - Computing, A - Meanings for A

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When, early in the history of personal computers, users didn't find their character encoding requirements met, private or local codepages were created using Terminate and Stay Resident utilities or by re-programming BIOS EPROMs. In some cases, unofficial code page numbers were invented (e.g., cp895). When more diverse character set support became available most of those code pages fell into disuse, with some exceptions such as the Kamenický or KEYB ...

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Code page, Code page - Background, Code page - Relationship to ASCII, Code page - Partial list of IBM code pages, Code page - Other code pages of note, Code page - Microsoft code pages, Code page - Private code pages

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A few code pages use more than 8 bits per character and thus encode more than 256 characters. The term cmap (character map) is used in technical documentation on Macintosh platforms. Although IBM created and maintained many code pages, the term came to be associated primarily with character maps used by the IBM PC and compatible platforms, especially prior to the advent of Unicode-capable prog ...

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Code page, Code page - Background, Code page - Relationship to ASCII, Code page - Partial list of IBM code pages, Code page - Other code pages of note, Code page - Microsoft code pages, Code page - Private code pages

Read more here: » Code page: Encyclopedia II - Code page - Background

There are many algorithms for processing strings, each with various tradeoffs. Some categories of algorithms include string searching algorithms for finding a given substring or pattern; sorting algorithms; regular expression algorithms; and parsing a string. Advanced string algorithms often employ complex mechanisms and data structures, among them suffix trees and finite state machines. ...

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String computer science, String computer science - String datatypes, String computer science - Representations, String computer science - Memory management, String computer science - String algorithms, String computer science - String oriented languages and utilities, String computer science - Formal theory

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Strings are such a useful datatype that several languages have been designed in order to make string processing applications easy to write. Examples include the following languages: awk Icon Perl Ruby Tcl MUMPS Rexx sed SNOBOL Many UNIX utilities perform simple string manipulations and can be used to easily program some powerf ...

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String computer science, String computer science - String datatypes, String computer science - Representations, String computer science - Memory management, String computer science - String algorithms, String computer science - String oriented languages and utilities, String computer science - Formal theory

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ASCII was developed simultaneously by the ISO and the ASA, the predecessor organization to ANSI. During the period 1963-1968, the ISO draft standards supported the use of either CR+LF or LF alone as a newline, while the ASA drafts supported only CR+LF. The Multics operating system began development in 1964 and used LF alone as its newline. Unix followed the Multics practic ...

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Newline, Newline - Representations, Newline - Unicode, Newline - History, Newline - Newline in programming languages, Newline - Common problems, Newline - Conversion utilities

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The NATO phonetic alphabet represents I as India. In international Morse code the letter I is dit dit, ·· In Braille the letter I is represented as ⠊ (in Unicode), with the dot pattern, The International maritime signal flag for I is, I - Computing. In Unicode the capital I is codepoint U+0049 and the lowercase i is U+0069. The ASCII code for capital I is 73 and for lowercase i is 105; or ...

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I, I - History, I - Alternative representations, I - Computing, I - Meanings for I

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This standard was originally used for specifying the connection between an electromechanical teletypewriter and a modem. When electronic terminals (smart and dumb) began to be used, they were often designed to be interchangeable with teletypes, and so supported RS-232. The C revision of the standard was issued in 1969 in part to accommodate the electrical characteristics of these devices. Since application to such devices as computers, printers, digitizer tables, test instruments, and so on were not envisioned in the standard, designe ...

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RS-232, RS-232 - Scope of the standard, RS-232 - History, RS-232 - Limitations of the standard, RS-232 - Role in modern computing, RS-232 - Standard details, RS-232 - Voltage levels, RS-232 - Connectors, RS-232 - Cables, RS-232 - Seldom used features, RS-232 - Signal rate selection, RS-232 - Loopback testing, RS-232 - Timing signals, RS-232 - Secondary channel, RS-232 - Related standards, RS-232 - Related Wikibooks

Read more here: » RS-232: Encyclopedia II - RS-232 - History

In the book "PC 97 Hardware Design Guide" [1], Microsoft deprecated support for the RS-232 compatible serial port of the original IBM PC design. Today, RS-232 is gradually being superseded in personal computers by USB for local communications. Compared with RS-232, USB is faster, has lower voltage levels, has connectors that are simpler to connect and use. USB has software support in popular operating systems. USB is designed to make it easy for device drivers to communicate with hardware, and there is no direct analog to the terminal progra ...

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RS-232, RS-232 - Scope of the standard, RS-232 - History, RS-232 - Limitations of the standard, RS-232 - Role in modern computing, RS-232 - Standard details, RS-232 - Voltage levels, RS-232 - Connectors, RS-232 - Cables, RS-232 - Seldom used features, RS-232 - Signal rate selection, RS-232 - Loopback testing, RS-232 - Timing signals, RS-232 - Secondary channel, RS-232 - Related standards, RS-232 - Related Wikibooks

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The EIA-232 standard specifies connections for several features that are not used in most implementations. Their use requires the 25-pin connectors and cables, and of course both the DTE and DCE must support them. RS-232 - Signal rate selection. The DTE or DCE can specify use of a "high" or "low" signaling rate. The rates as well as which device will select the rate must be configured in both the DTE and DCE. The prearranged device selects the high rate by setting pin 23 to ON. < ...

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RS-232, RS-232 - Scope of the standard, RS-232 - History, RS-232 - Limitations of the standard, RS-232 - Role in modern computing, RS-232 - Standard details, RS-232 - Voltage levels, RS-232 - Connectors, RS-232 - Cables, RS-232 - Seldom used features, RS-232 - Signal rate selection, RS-232 - Loopback testing, RS-232 - Timing signals, RS-232 - Secondary channel, RS-232 - Related standards, RS-232 - Related Wikibooks

Read more here: » RS-232: Encyclopedia II - RS-232 - Seldom used features

The EIA standard RS-232-C as of 1969 defines: Electrical signal characteristics such as voltage levels, signaling rate, timing and slew-rate of signals, voltage withstand level, short-circuit behavior, maximum stray capacitance and cable length Interface mechanical characteristics, pluggable connectors and pin identification Functions of each circuit in the interface connector Standard subsets of interface c ...

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RS-232, RS-232 - Scope of the standard, RS-232 - History, RS-232 - Limitations of the standard, RS-232 - Role in modern computing, RS-232 - Standard details, RS-232 - Voltage levels, RS-232 - Connectors, RS-232 - Cables, RS-232 - Seldom used features, RS-232 - Signal rate selection, RS-232 - Loopback testing, RS-232 - Timing signals, RS-232 - Secondary channel, RS-232 - Related standards, RS-232 - Related Wikibooks

Read more here: » RS-232: Encyclopedia II - RS-232 - Scope of the standard

System/360 - Key features of lasting impact. The System/360 introduced a number of industry standards to the marketplace, such as: The 8-bit byte (against financial pressure during development to reduce the byte to 4 or 6 bits) Byte-addressable memory (as opposed to word-addressable memory) 32-bit words Two's complement arithmetic Segmented and paged memory Commercial use of microcoded CPUs The IBM Floating Point Architecture (until superseded by ...

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System/360, System/360 - System/360 history, System/360 - A family of computers, System/360 - The project's size and gravity, System/360 - Models, System/360 - Successors and variants, System/360 - Technical description, System/360 - Key features of lasting impact, System/360 - Architectural overview, System/360 - Basic hardware components, System/360 - Operating system software, System/360 - Remaining machines, System/360 - Notes

Read more here: » System/360: Encyclopedia II - System/360 - Technical description

Unicode covers almost all scripts (writing systems) in current use today, including: Arabic Armenian Bengali Braille embossing patterns Canadian Aboriginal Syllabics Cherokee Coptic Cyrillic Devanāgarī Ethiopic Georgian Greek Gujarati Gurmukhi Hangul (Korean) Han (Kanji, Hanja, Hanzi) Japanese (Kanji, Hiragana and Katakana) Hebrew Khmer (Cambodian)

Unicode - Operating systems. Despite technical problems and limitations and criticism on process, Unicode has emerged as the dominant encoding scheme. Windows NT and its descendants Windows 2000 and Windows XP make extensive use of UTF-16 as an internal representation of text. Unix-like operating systems such as GNU/Linux, Plan 9, BSD and Mac OS X have adopted UTF-8 as the bas ...

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Unicode, Unicode - Origin and development, Unicode - Scripts covered, Unicode - Trivia, Unicode - Mapping and encodings, Unicode - Standard, Unicode - Storage transfer and processing, Unicode - Ready-made versus composite characters, Unicode - Issues, Unicode - Unicode in use, Unicode - Operating systems, Unicode - E-mail, Unicode - Web, Unicode - Fonts, Unicode - Multilingual text-rendering engines, Unicode - Input methods

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Other serial signalling standards may not interoperate with standard-compliant RS 232 ports. For example, using the TTL levels of +5 and 0 V puts the mark level in the undefined area of the standard. Such levels are sometimes used with NMEA-compliant GPS receivers and depth finders. 20 mA current loop uses the absence of 20 mA current for high, and the presence of current in the loop for low; this signal level is often used for long-distance and optically isolated links. Connection of a current-loop device to a compliant RS 232 port r ...

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RS-232, RS-232 - Scope of the standard, RS-232 - History, RS-232 - Limitations of the standard, RS-232 - Role in modern computing, RS-232 - Standard details, RS-232 - Voltage levels, RS-232 - Connectors, RS-232 - Cables, RS-232 - Seldom used features, RS-232 - Signal rate selection, RS-232 - Loopback testing, RS-232 - Timing signals, RS-232 - Secondary channel, RS-232 - Related standards, RS-232 - Related Wikibooks

Read more here: » RS-232: Encyclopedia II - RS-232 - Related standards

BCD is very common in electronic systems where a numeric value is to be displayed, especially in systems consisting solely of digital logic, and not containing a microprocessor. By utilising BCD, the manipulation of numerical data for display can be greatly simplified by treating each digit as a separate single sub-circuit. This matches much more closely the physical reality of display hardware—a designer might choose to use a series of separate identical 7-segment displays to build a metering circuit, for example. If the numeric quantity ...

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Binary-coded decimal, Binary-coded decimal - Basics, Binary-coded decimal - BCD in electronics, Binary-coded decimal - Higher-density encoding, Binary-coded decimal - IBM and BCD, Binary-coded decimal - Addition With BCD, Binary-coded decimal - Background, Binary-coded decimal - Legal history, Binary-coded decimal - Comparison with pure binary, Binary-coded decimal - Advantages, Binary-coded decimal - Disadvantages, Binary-coded decimal - Reference

Read more here: » Binary-coded decimal: Encyclopedia II - Binary-coded decimal - BCD in electronics

Software applications and operating systems usually represent the newline with one or two control characters: Systems based on ASCII or a compatible character set use either LF (Line Feed, 0x0A) or CR (Carriage Return, 0x0D) individually, or CR followed by LF (CR+LF, 0x0D 0x0A). LF:    Unix and Unix-like systems, Linux, AIX, Xenix, Mac OS X, BeOS, Amiga, RISC OS and others CR+LF: C ...

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Newline, Newline - Representations, Newline - Unicode, Newline - History, Newline - Newline in programming languages, Newline - Common problems, Newline - Conversion utilities

Read more here: » Newline: Encyclopedia II - Newline - Representations

The Unicode standard addresses the problem by defining a large number of characters that conforming applications should recognize as line terminators:  LF:    Line Feed, u000A  CR:    Carriage Return, u000D  CR+LF: CR followed by LF  NEL:   Next Line, u0085  FF:    Form Feed, u000C See also:

Newline, Newline - Representations, Newline - Unicode, Newline - History, Newline - Newline in programming languages, Newline - Common problems, Newline - Conversion utilities

Read more here: » Newline: Encyclopedia II - Newline - Unicode

Binary-coded decimal - Advantages. Scaling by a factor of 10 (or a power of 10) is simple, this is useful when a decimal scaling factor is needed to represent a non-integer quantity (e.g., in financial calculations where it is required that a computer gets the same result that a human would). Conversion to a character form or for display (e.g., to a character encoding such as XML, or to drive signals for a 7 segment display) is a simple per-digit mapping (conversion from pure binary involves relatively complex logic that spans digits, and get ...

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Binary-coded decimal, Binary-coded decimal - Basics, Binary-coded decimal - BCD in electronics, Binary-coded decimal - Higher-density encoding, Binary-coded decimal - IBM and BCD, Binary-coded decimal - Addition With BCD, Binary-coded decimal - Background, Binary-coded decimal - Legal history, Binary-coded decimal - Comparison with pure binary, Binary-coded decimal - Advantages, Binary-coded decimal - Disadvantages, Binary-coded decimal - Reference

Read more here: » Binary-coded decimal: Encyclopedia II - Binary-coded decimal - Comparison with pure binary