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PL360
PL360 (or PL/360) is a system programming language designed by Niklaus Wirth and written by Wirth, Joseph W. Wells Jr., and Edwin Satterthwaite Jr. for the IBM System/360 computer at Stanford University. A description of PL360 was published in early 1968, although the implementation was probably completed before Wirth left Stanford in 1967. Description PL/360 is a one pass compiler with a syntax similar to ALGOL that provides facilities for specifying exact machine code (language) instructions and registers similar to assembly language, but also provides features commonly found in high-level programming languages, such as complex arithmetic expressions and control structures. Wirth used PL360 to create ALGOL W. Data types are: * Byte or character – 1 byte * Short integer – 2 bytes, interpreted as an integer in two's complement binary notation * Integer or logical – 4 bytes, interpreted as an integer in two's complement binary notation * Real – 4 bytes, interpreted as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
System Programming Language
A system programming language is a programming language used for system programming; such languages are designed for writing system software, which usually requires different development approaches when compared with application software. Edsger W. Dijkstra, Edsger Dijkstra refers to these language as Machine Oriented High Order Languages, or mohol. Proceedings published 1974. General-purpose programming languages tend to focus on generic features to allow programs written in the language to use the same code on different platforms. Examples of such languages include ALGOL and Pascal (programming language), Pascal. This generic quality typically comes at the cost of denying direct access to the machine's internal workings, and this often has negative effects on performance. System languages, in contrast, are designed not for compatibility, but for performance and ease of access to the underlying hardware while still providing high-level programming concepts like structured program ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ALGOL W
ALGOL W is a programming language. It is based on a proposal for ALGOL X by Niklaus Wirth and Tony Hoare as a successor to ALGOL 60. ALGOL W is a relatively simple upgrade of the original ALGOL 60, adding string, bitstring, complex number and reference to record data types and call-by-result passing of parameters, introducing the while statement, replacing switch with the case statement, and generally tightening up the language. Wirth's entry was considered too little of an advance over ALGOL 60, and the more complex entry from Adriaan van Wijngaarden was selected in a highly contentious meeting. Wirth later published his version as ''A contribution to the development of ALGOL''. With a number of small additions, this eventually became ALGOL W. Wirth supervised a high quality implementation for the IBM System/360 at Stanford University that was widely distributed. (Various documents for Stanford's 1972 implementation of ALGOL W; this report includes the ''ALGOL W Language ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niklaus Wirth
Niklaus Emil Wirth (born 15 February 1934) is a Swiss computer scientist. He has designed several programming languages, including Pascal, and pioneered several classic topics in software engineering. In 1984, he won the Turing Award, generally recognized as the highest distinction in computer science, for developing a sequence of innovative computer languages. Biography Wirth was born in Winterthur, Switzerland, in 1934. In 1959, he earned a Bachelor of Science (B.S.) degree in electronic engineering from the Swiss Federal Institute of Technology Zürich (ETH Zürich). In 1960, he earned a Master of Science (MSc) from Université Laval, Canada. Then in 1963, he was awarded a PhD in Electrical Engineering and Computer Science (EECS) from the University of California, Berkeley, supervised by the computer design pioneer Harry Huskey. From 1963 to 1967, he served as assistant professor of computer science at Stanford University and again at the University of Zurich. Then ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-level Assembler
A high-level assembler in computing is an assembler for assembly language that incorporate features found in a high-level programming language. The earliest high-level assembler was probably Burroughs' Executive Systems Problem Oriented Language (ESPOL) in about 1960, which provided an ALGOL-like syntax around explicitly-specified Burroughs B5000 machine instructions. This was followed by Niklaus Wirth's PL360 in 1968; this replicated the Burroughs facilities, with which he was familiar, on an IBM System/360. More recent high-level assemblers are Borland's Turbo Assembler (TASM), Netwide Assembler (NASM), Microsoft's Macro Assembler (MASM), IBM's High Level Assembler (HLASM) for z/Architecture systems, Alessandro Ghignola's Linoleum, X# used in Cosmos and Ziron. High-level assemblers typically provide instructions that directly assemble one-to-one into low-level machine code as in any assembler, plus control statements such as IF, WHILE, REPEAT...UNTIL, and FOR, macros, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM PL/S
PL/S, short for Programming Language/Systems, is a "machine-oriented" programming language based on PL/I. It was developed by IBM in the late 1960s, under the name Basic Systems Language (BSL), as a replacement for assembly language on internal software projects; it included support for inline assembly and explicit control over register usage. Early projects using PL/S were the batch utility, IEHMOVE, and the Time Sharing Option of MVT, TSO. By the 1970s, IBM was rewriting its flagship operating system in PL/S. Although users frequently asked IBM to release PL/S for their use, IBM refused saying that the product was proprietary. Their concern was that open PL/S would give competitors, Amdahl, Itel (National Advanced Systems), Storage Technology Corporation, Trilogy Systems, Magnuson Computer Systems, Fujitsu, Hitachi, and other PCM vendors a competitive advantage. However, even though they refused to make available a compiler, they shipped the PL/S source code to larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stanford Physics Information Retrieval System
The Stanford Physics Information Retrieval System (SPIRES) is a database management system developed by Stanford University. It is used by universities, colleges and research institutions. The first website in North America was created to allow remote users access to its database. History SPIRES was originally developed at the Stanford Linear Accelerator Center (SLAC) in 1969, from a design based on a 1967 information study of physicists at SLAC. The system was designed as a physics database management system (DBMS) to deal with high-energy-physics preprints. Written in PL/I, SPIRES ran on an IBM System/360. In the early 1970s, an evaluation of this system resulted in the decision to implement a new system for use by faculty, staff and students at Stanford University. SPIRES was renamed the Stanford Public Information Retrieval System. The new development took place under a National Science Foundation grant headed by Edwin B. Parker, principal investigator. SPIRES joined force ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Procedural Programming
Procedural programming is a programming paradigm, derived from imperative programming, based on the concept of the '' procedure call''. Procedures (a type of routine or subroutine) simply contain a series of computational steps to be carried out. Any given procedure might be called at any point during a program's execution, including by other procedures or itself. The first major procedural programming languages appeared circa 1957–1964, including Fortran, ALGOL, COBOL, PL/I and BASIC. Pascal and C were published circa 1970–1972. Computer processors provide hardware support for procedural programming through a stack register and instructions for calling procedures and returning from them. Hardware support for other types of programming is possible, but no attempt was commercially successful (for example Lisp machines or Java processors). Procedures and modularity Modularity is generally desirable, especially in large, complicated programs. Inputs are usually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drum Memory
Drum memory was a magnetic data storage device invented by Gustav Tauschek in 1932 in Austria. Drums were widely used in the 1950s and into the 1960s as computer memory. For many early computers, drum memory formed the main working memory of the computer. It was so common that these computers were often referred to as ''drum machines''. Some drums were also used as secondary storage as for example various IBM drum storage drives. Drums were displaced as primary computer memory by magnetic core memory, which offered a better balance of size, speed, cost, reliability and potential for further improvements. Drums in turn were replaced by hard disk drives for secondary storage, which were both less expensive and offered denser storage. The manufacturing of drums ceased in the 1970s. Technical design A drum memory or drum storage unit contained a large metal cylinder, coated on the outside surface with a ferromagnetic recording material. It could be considered the precursor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floating-point Arithmetic
In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can be represented as a base-ten floating-point number: 12.345 = \underbrace_\text \times \underbrace_\text\!\!\!\!\!\!^ In practice, most floating-point systems use base two, though base ten ( decimal floating point) is also common. The term ''floating point'' refers to the fact that the number's radix point can "float" anywhere to the left, right, or between the significant digits of the number. This position is indicated by the exponent, so floating point can be considered a form of scientific notation. A floating-point system can be used to represent, with a fixed number of digits, numbers of very different orders of magnitude — such as the number of meters between galaxies or between protons in an atom. For this reason, floating-p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euler (programming Language)
Euler is a programming language created by Niklaus Wirth and Helmut Weber, conceived as an extension and generalization of ALGOL 60. The designers' goals were to create a language that is: * Simpler, yet more flexible, than ALGOL 60 * Useful and processed with reasonable efficiency * Definable with rigorous formality Available sources indicate that Euler was operational by 1965. Overview Euler employs a general data type concept. In Euler, arrays, procedures, and switches are not quantities which are declared and named by identifiers: in contrast to ALGOL, they are not quantities on the same level as variables. Rather, these quantities are on the level of numeric and boolean constants. Thus, besides the traditional numeric and logical constants, Euler introduces several added types: * Reference * Label * Symbol * List (array) * Procedure * Undefined All constants can be assigned to variables, which have the same form as in ALGOL, but for which no fixed types are specified: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM Basic Assembly Language And Successors
Basic Assembly Language (BAL) is the commonly used term for a low-level programming language used on IBM System/360 and successor mainframes. Originally, "Basic Assembly Language" applied only to an extremely restricted dialect designed to run under control of IBM Basic Programming Support (BPS/360) on systems with only 8 KB of main memory, and only a card reader, a card punch, and a printer for input/output — thus the word "Basic". However, the full name and the initialism "BAL" almost immediately attached themselves in popular use to all assembly-language dialects on the System/360 and its descendants. BAL for BPS/360 was introduced with the System/360 in 1964. Assemblers on other System/360 operating systems through System/370, System/390, and System z, as well as the UNIVAC Series 90 mainframes made by Sperry Corporation, and the BS2000 Mainframes currently made by Fujitsu, inherited and extended its syntax. The latest derived language is known as the IBM High-Le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disk Storage
Disk storage (also sometimes called drive storage) is a general category of storage mechanisms where data is recorded by various electronic, magnetic, optical, or mechanical changes to a surface layer of one or more rotating disks. A disk drive is a device implementing such a storage mechanism. Notable types are the hard disk drive (HDD) containing a non-removable disk, the floppy disk drive (FDD) and its removable floppy disk, and various optical disc drives (ODD) and associated optical disc media. (The spelling ''disk'' and ''disc'' are used interchangeably except where trademarks preclude one usage, e.g. the Compact Disc logo. The choice of a particular form is frequently historical, as in IBM's usage of the ''disk'' form beginning in 1956 with the " IBM 350 disk storage unit".) Background Audio information was originally recorded by analog methods (see Sound recording and reproduction). Similarly the first video disc used an analog recording method. In the music ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
