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ALGOL 68RS
ALGOL 68RS is the second ALGOL 68 compiler written by I. F. Currie and J. D. Morrison, at the Royal Signals and Radar Establishment (RSRE). Unlike the earlier ALGOL 68-R, it was designed to be portable, and implemented the language of the Revised Report. Versions of ALGOL 68RS were written for the ICL 2900 Series, Multics, and VAX running VMS. Subsequently, parts of this compiler were released into the public domain, as a translator from ALGOL 68 to C, as part of the public release of the hardware description language ELLA, also by the RSRE. History Although the ALGOL 68-R compiler, written by I.F. Currie, J.D. Morrison, and S.G. Bond, was a great success, it suffered from two major problems: it had been written for the nearly obsolete ICL 1900 computer, and it implemented an out-of-date version of the language as it was released before the Revised Report on ALGOL 68 was available. RSRE needed a newer compiler for various internal projects, so the team of Currie and Morris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Signals And Radar Establishment
The Royal Signals and Radar Establishment (RSRE) was a scientific research establishment within the Ministry of Defence (MoD) of the United Kingdom. It was located primarily at Malvern in Worcestershire, England. The RSRE motto was ''Ubique Sentio'' (Latin for "I sense everywhere"). History RSRE was formed in 1976 by an amalgamation of previous research organizations; these included the Royal Radar Establishment (RRE), itself derived from the World War II-era Telecommunications Research Establishment, the Signals Research and Development Establishment (SRDE) in Christchruch, Dorset, and the Services Electronic Research Laboratory (SERL) at Baldock. Beginning in 1979, the SRDE and SERL moved to Malvern to join the RRE's location.EdsRobert Budand Philip Gummett, ''Cold War Hot Science: Applied Research in Britain's Defence Laboratories 1945-1990'', Harwood, 1999 There were several out-stations in Worcestershire, including the ex-RAF airfields at Defford and Pershore and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-platform Software
In computing, cross-platform software (also called multi-platform software, platform-agnostic software, or platform-independent software) is computer software that is designed to work in several computing platforms. Some cross-platform software requires a separate build for each platform, but some can be directly run on any platform without special preparation, being written in an interpreted language or compiled to portable bytecode for which the interpreters or run-time packages are common or standard components of all supported platforms. For example, a cross-platform application may run on Microsoft Windows, Linux, and macOS. Cross-platform software may run on many platforms, or as few as two. Some frameworks for cross-platform development are Codename One, Kivy, Qt, Flutter, NativeScript, Xamarin, Phonegap, Ionic, and React Native. Platforms ''Platform'' can refer to the type of processor (CPU) or other hardware on which an operating system (OS) or application runs, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Input/output
In computing, input/output (I/O, or informally io or IO) is the communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system. Inputs are the signals or data received by the system and outputs are the signals or data sent from it. The term can also be used as part of an action; to "perform I/O" is to perform an input or output operation. are the pieces of hardware used by a human (or other system) to communicate with a computer. For instance, a keyboard or computer mouse is an input device for a computer, while monitors and printers are output devices. Devices for communication between computers, such as modems and network cards, typically perform both input and output operations. Any interaction with the system by a interactor is an input and the reaction the system responds is called the output. The designation of a device as either input or output depends on perspective. Mice a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
One-pass Compiler
In computer programming, a one-pass compiler is a compiler that passes through the parts of each compilation unit only once, immediately translating each part into its final machine code. This is in contrast to a multi-pass compiler which converts the program into one or more intermediate representations in steps between source code and machine code, and which reprocesses the entire compilation unit in each sequential pass. This refers to the logical functioning of the compiler, not to the actual reading of the source file once only. For instance, the source file could be read once into temporary storage but that copy could then be scanned many times. The IBM 1130 Fortran compiler stored the source in memory and used many passes; by contrast the assembler, on systems lacking a disc storage unit, required that the source deck of cards be presented twice to the card reader/punch. Properties One-pass compilers are smaller and faster than multi-pass compilers. One-pass compilers a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flex Machine
The Flex Computer System was developed by Michael Foster and Ian Currie of Royal Signals and Radar Establishment (RSRE) in Malvern, England, during the late 1970s and 1980s. It used a tagged storage scheme to implement a capability architecture, and was designed for the safe and efficient implementation of strongly typed procedures. The hardware was custom and microprogrammable, with an operating system, (modular) compiler, editor, garbage collector and filing system all written in ALGOL 68RS. There were (at least) two incarnations of Flex, implemented using hardware with writable microcode. The first was supplied by Logica to an RSRE design, and the second used an ICL PERQ. The microcode alone was responsible for storage allocation, deallocation and garbage collection. This immediately precluded a whole class of errors arising from the misuse (deliberate or accidental) of pointers. A notable feature of Flex was the tagged, write-once filestore. This allowed arbitrary code ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altran Praxis
Altran UK (formerly known as Altran Praxis, Praxis High Integrity Systems, Praxis Critical Systems, Altran Xype, Xype and Altran Technologies) is a division of parent company Altran. Altran Praxis was a British software house that specialised in critical systems. This role is continued under the banner of high-tech engineering consultancy services provided by the rest of the Altran group. The division formerly known as Praxis (the critical systems specialists) is based in SouthGate, Bath, England, close to Bath Spa railway station, and also have offices in London, Loughborough, Paris, Sophia Antipolis, and Bangalore. Altran UK as a whole has offices in Bath, Bristol, London, Loughborough, Manchester, Slough and Coventry. The company Praxis Systems Limited was founded by Martyn Thomas and David Bean in 1983: it was incorporated on 1 June 1983 and commenced business on 1 July 1983. On 28 June 1985 it became a Public limited company Praxis Systems plc. Until 1988, Praxis was ... [...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 wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Computers Limited
International Computers Limited (ICL) was a British computer hardware, computer software and computer services company that operated from 1968 until 2002. It was formed through a merger of International Computers and Tabulators (ICT), English Electric Computers (EEC) and Elliott Automation in 1968. The company's most successful product line was the ICL 2900 Series range of mainframe computers. In later years, ICL diversified its product line but the bulk of its profits always came from its mainframe customers. New ventures included marketing a range of powerful IBM clones made by Fujitsu, various minicomputer and personal computer ranges and (more successfully) a range of retail point-of-sale equipment and back-office software. Although it had significant sales overseas, ICL's mainframe business was dominated by large contracts from the UK public sector, including Post Office Ltd, the Inland Revenue, the Department for Work and Pensions and the Ministry of Defence. It also had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martyn Thomas
Martyn Thomas CBE FREng FIET FRSA (born 1948) is a British independent consultant and software engineer. Overview Martyn Thomas founded the software engineering company Praxis in 1983, based in Bath, southern England. He has a special interest in safety-critical systems and other high integrity applications. He has acted as an expert witness involving complex software engineering issues. Thomas was born in Salisbury, southern England. He studied biochemistry at University College London, graduating in 1969, when he started working in the field of computing. Between 1969 and 1983, he was employed at universities in London and the Netherlands, at STC working on telecommunications software, and at the South West Universities Regional Computer Centre in Bath. In 1983, Thomas founded Praxis with David Bean, where he encouraged the use of formal methods within the company for software development. In 1986, Praxis became the first independent systems house to achieve BS 5750 (l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxford University Computing Services
Oxford University Computing Services (OUCS) until 2012 provided the central Information Technology services for the University of Oxford. The service was based at 7-19 Banbury Road in central north Oxford, England, near the junction with Keble Road. OUCS became part of IT Services, when the new department was created at the University of Oxford on 1 August 2012 through a merger of the three previous central IT departments: Oxford University Computing Services (OUCS), Business Services and Projects (BSP) and ICT Support Team (ICTST). At the time when Oxford University Computing Services ceased to operate as an independent department, it offered facilities, training and advice to members of the university in all aspects of academic computing. OUCS was responsible for the core networks reaching all departments and colleges of Oxford University. OUCS was made up of 5 technical and one administration group. Each group had responsibility for different aspects of OUCS services supplied t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bootstrapping (compilers)
In computer science, bootstrapping is the technique for producing a self-compiling compiler – that is, a compiler (or assembler) written in the source programming language that it intends to compile. An initial core version of the compiler (the ''bootstrap compiler'') is generated in a different language (which could be assembly language); successive expanded versions of the compiler are developed using this minimal subset of the language. The problem of compiling a self-compiling compiler has been called the chicken-or-egg problem in compiler design, and bootstrapping is a solution to this problem. Many compilers for many programming languages are bootstrapped, including compilers for BASIC, ALGOL, C, C#, D, Pascal, PL/I, Haskell, Modula-2, Oberon, OCaml, Common Lisp, Scheme, Go, Java, Elixir, Rust, Python, Scala, Nim, Eiffel, TypeScript, Vala, Zig and more. Process A typical bootstrap process works in three or four stages: * Stage 0: preparing an environment for the ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Character Encoding
Character encoding is the process of assigning numbers to Graphics, graphical character (computing), characters, especially the written characters of Language, human language, allowing them to be Data storage, stored, Data communication, transmitted, and Computing, transformed using Digital electronics, digital computers. The numerical values that make up a character encoding are known as "code points" and collectively comprise a "code space", a "code page", or a "Character Map (Windows), character map". Early character codes associated with the optical or electrical Telegraphy, telegraph could only represent a subset of the characters used in written languages, sometimes restricted to Letter case, upper case letters, Numeral system, numerals and some punctuation only. The low cost of digital representation of data in modern computer systems allows more elaborate character codes (such as Unicode) which represent most of the characters used in many written languages. Character enc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
