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IBM 8000
The IBM 8000 series was a proposed transistor-based successor to the IBM 7000 series. Important engineers on the project included Fred Brooks and Gerry Blaauw. The project plan for the 8000 series was presented by Fred Brooks in January 1961. Despite some technical successes, the project became a political football, amid IBM's search for a unified product line. The project was canceled in 1961 by Bob Evans, supplanted by the successful System/360 series. The 8000 project may have seen the first use of the term "architecture" in relation to computers. Problems Pugh cites a number of reasons for the cancellation of the 8000 line. * Because more integrated technology was not yet available the system was to have been built using ''discrete transistor'' (SMS) components. * The proposed systems would have been incompatible with IBM's existing successful 1400 series systems. * The proposed instruction set was too complex. * The systems offered inadequate floating point performance, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/360
The IBM System/360 (S/360) is a family of mainframe computer systems that was announced by IBM on April 7, 1964, and delivered between 1965 and 1978. It was the first family of computers designed to cover both commercial and scientific applications and to cover a complete range of applications from small to large. The design distinguished between architecture and implementation, allowing IBM to release a suite of compatible designs at different prices. All but the only partially compatible Model 44 and the most expensive systems use microcode to implement the instruction set, which features 8-bit byte addressing and binary, decimal, and hexadecimal floating-point calculations. The System/360 family introduced IBM's Solid Logic Technology (SLT), which packed more transistors onto a circuit card, allowing more powerful but smaller computers to be built. The slowest System/360 model announced in 1964, the Model 30, could perform up to 34,500 instructions per second, with memo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 1400 Series
The IBM 1400 series were second-generation (transistor) mid-range business decimal computers that IBM marketed in the early 1960s. The computers were offered to replace tabulating machines like the IBM 407. The 1400-series machines stored information in magnetic cores as variable-length character strings separated on the left by a special bit, called a "wordmark," and on the right by a "record mark." Arithmetic was performed digit-by-digit. Input and output support included punched card, magnetic tape, and high-speed line printers. Disk storage was also available. Many members of the series could be used as independent systems, as extensions to IBM punched-card equipment, or as auxiliary equipment to other computer systems. Some, however, were intended for specific applications or were economical only as independent systems. History The 1401, announced on October 5, 1959, was the first member of the IBM 1400 series. It was the first computer to deploy over 10,000 units. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIT Press
The MIT Press is a university press affiliated with the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts (United States). It was established in 1962. History The MIT Press traces its origins back to 1926 when MIT published under its own name a lecture series entitled ''Problems of Atomic Dynamics'' given by the visiting German physicist and later Nobel Prize winner, Max Born. Six years later, MIT's publishing operations were first formally instituted by the creation of an imprint called Technology Press in 1932. This imprint was founded by James R. Killian, Jr., at the time editor of MIT's alumni magazine and later to become MIT president. Technology Press published eight titles independently, then in 1937 entered into an arrangement with John Wiley & Sons in which Wiley took over marketing and editorial responsibilities. In 1962 the association with Wiley came to an end after a further 125 titles had been published. The press acquired its modern name af ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 7090
The IBM 7090 is a second-generation transistorized version of the earlier IBM 709 vacuum tube mainframe computer that was designed for "large-scale scientific and technological applications". The 7090 is the fourth member of the IBM 700/7000 series scientific computers. The first 7090 installation was in December 1959. In 1960, a typical system sold for $2.9 million (equivalent to $ million in ) or could be rented for $63,500 a month (). The 7090 uses a 36-bit word length, with an address space of 32,768 words (15-bit addresses). It operates with a basic memory cycle of 2.18 μs, using the IBM 7302 Core Storage core memory technology from the IBM 7030 (Stretch) project. With a processing speed of around 100 Kflop/s, the 7090 is six times faster than the 709, and could be rented for half the price. An upgraded version, the 7094 was up to twice as fast. Both the 7090 and the 7094 were withdrawn from sale on July 14, 1969, but systems remained in service for more than a deca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Index Register
An index register in a computer's CPU is a processor register (or an assigned memory location) used for pointing to operand addresses during the run of a program. It is useful for stepping through strings and arrays. It can also be used for holding loop iterations and counters. In some architectures it is used for read/writing blocks of memory. Depending on the architecture it maybe a dedicated index register or a general-purpose register. Some instruction sets allow more than one index register to be used; in that case additional instruction fields may specify which index registers to use. Generally, the contents of an index register is added to (in some cases subtracted from) an ''immediate'' address (that can be part of the instruction itself or held in another register) to form the "effective" address of the actual data (operand). Special instructions are typically provided to test the index register and, if the test fails, increments the index register by an immediate con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Front End Processor
A front end processor (FEP), or a communications processor, is a small-sized computer which interfaces to the host computer a number of networks, such as SNA, or a number of peripheral devices, such as terminals, disk units, printers and tape units. Data is transferred between the host computer and the front end processor using a high-speed parallel interface. The front end processor communicates with peripheral devices using slower serial interfaces, usually also through communication networks. The purpose is to off-load from the host computer the work of managing the peripheral devices, transmitting and receiving messages, packet assembly and disassembly, error detection, and error correction. Two examples are the IBM 3705 Communications Controller and the Burroughs Data Communications Processor. Sometimes FEP is synonymous with a communications controller, although the latter is not necessarily as flexible. Early communications controllers such as the IBM 270x series w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Segmentation
Memory segmentation is an operating system memory management technique of division of a computer's primary memory into segments or sections. In a computer system using segmentation, a reference to a memory location includes a value that identifies a segment and an offset (memory location) within that segment. Segments or sections are also used in object files of compiled programs when they are linked together into a program image and when the image is loaded into memory. Segments usually correspond to natural divisions of a program such as individual routines or data tables so segmentation is generally more visible to the programmer than paging alone. Segments may be created for program modules, or for classes of memory usage such as code and data segments. Certain segments may be shared between programs. Segmentation was originally invented as a method by which system software could isolate software processes ( tasks) and data they are using. It was intended to increase relia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic-core Memory
Magnetic-core memory was the predominant form of random access, random-access computer memory for 20 years between about 1955 and 1975. Such memory is often just called core memory, or, informally, core. Core memory uses toroids (rings) of a hard magnetic material (usually a Ferrite (magnet)#Semi-hard ferrites, semi-hard ferrite) as transformer cores, where each wire threaded through the core serves as a transformer winding. Two or more wires pass through each core. Magnetic Magnetic hysteresis, hysteresis allows each of the cores to "remember", or store a state. Each core stores one bit of information. A core can be magnetized in either the clockwise or counter-clockwise direction. The value of the bit stored in a core is zero or one according to the direction of that core's magnetization. Electric current pulses in some of the wires through a core allow the direction of the magnetization in that core to be set in either direction, thus storing a one or a zero. Another wire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floating-point Unit
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-poi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instruction Set
In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ''implementation''. In general, an ISA defines the supported instructions, data types, registers, the hardware support for managing main memory, fundamental features (such as the memory consistency, addressing modes, virtual memory), and the input/output model of a family of implementations of the ISA. An ISA specifies the behavior of machine code running on implementations of that ISA in a fashion that does not depend on the characteristics of that implementation, providing binary compatibility between implementations. This enables multiple implementations of an ISA that differ in characteristics such as performance, physical size, and monetary cost (among other things), but that are capable of running the same machine code, so that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Architecture
In computer engineering, computer architecture is a description of the structure of a computer system made from component parts. It can sometimes be a high-level description that ignores details of the implementation. At a more detailed level, the description may include the instruction set architecture design, microarchitecture design, logic design, and implementation. History The first documented computer architecture was in the correspondence between Charles Babbage and Ada Lovelace, describing the analytical engine. When building the computer Z1 in 1936, Konrad Zuse described in two patent applications for his future projects that machine instructions could be stored in the same storage used for data, i.e., the stored-program concept. Two other early and important examples are: * John von Neumann's 1945 paper, First Draft of a Report on the EDVAC, which described an organization of logical elements; and *Alan Turing's more detailed ''Proposed Electronic Calculator'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 1400
The IBM 1400 series were second-generation (transistor) mid-range business decimal computers that IBM marketed in the early 1960s. The computers were offered to replace tabulating machines like the IBM 407. The 1400-series machines stored information in magnetic cores as variable-length character strings separated on the left by a special bit, called a "wordmark," and on the right by a "record mark." Arithmetic was performed digit-by-digit. Input and output support included punched card, magnetic tape, and high-speed line printers. Disk storage was also available. Many members of the series could be used as independent systems, as extensions to IBM punched-card equipment, or as auxiliary equipment to other computer systems. Some, however, were intended for specific applications or were economical only as independent systems. History The 1401, announced on October 5, 1959, was the first member of the IBM 1400 series. It was the first computer to deploy over 10,000 units. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
