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IBM System 370
The IBM System/370 (S/370) is a range of IBM mainframe computers announced as the successors to the System/360 family on June 30, 1970. The series mostly maintains backward compatibility with the S/360, allowing an easy migration path for customers; this, plus improved performance, were the dominant themes of the product announcement. Early 370 systems differed from the 360 largely in their internal circuitry, moving from the Solid Logic Technology hybrid integrated circuits containing separate transistors to more modern monolithic integrated circuits containing multiple transistors per integrated circuit, which IBM referred to as Monolithic System Technology, or MST. The higher density packaging allowed several formerly optional features from the 360 line to be included as standard features of the machines, floating-point support for instance. The 370 also added a small number of new instructions. At the time of its introduction, the development of virtual memory systems had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
32-bit Computing
In computer architecture, 32-bit computing refers to computer systems with a processor, memory, and other major system components that operate on data in a maximum of 32- bit units. Compared to smaller bit widths, 32-bit computers can perform large calculations more efficiently and process more data per clock cycle. Typical 32-bit personal computers also have a 32-bit address bus, permitting up to 4 GiB of RAM to be accessed, far more than previous generations of system architecture allowed. 32-bit designs have been used since the earliest days of electronic computing, in experimental systems and then in large mainframe and minicomputer systems. The first hybrid 16/32-bit microprocessor, the Motorola 68000, was introduced in the late 1970s and used in systems such as the original Apple Macintosh. Fully 32-bit microprocessors such as the HP FOCUS, Motorola 68020 and Intel 80386 were launched in the early to mid 1980s and became dominant by the early 1990s. This generat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/390
The IBM System/390 is a discontinued mainframe product family implementing ESA/390, the fifth generation of the System/360 instruction set architecture. The first computers to use the ESA/390 were the Enterprise System/9000 (ES/9000) family, which were introduced in 1990. These were followed by the 9672, Multiprise, and Integrated Server families of System/390 in 1994–1999, using CMOS microprocessors. The ESA/390 succeeded ESA/370, used in the Enhanced 3090 and 4381 "E" models, and the System/370 architecture last used in the IBM 9370 low-end mainframe. ESA/390 was succeeded by the 64-bit z/Architecture in 2000. History On September 5, 1990, IBM published a group of hardware and software announcements, two of which included overviews of three announcements: * System/390 (S/390), as in 360 for 1960s, 370 for 1970s. * Enterprise System/9000 (ES/9000), as in 360 for 1960s, 370 for 1970s. * Enterprise Systems Architecture/390 (ESA/390) was IBM's last 31-bit-address/32 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emulator
In computing, an emulator is Computer hardware, hardware or software that enables one computer system (called the ''host'') to behave like another computer system (called the ''guest''). An emulator typically enables the host system to run software or use peripheral devices designed for the guest system. Emulation refers to the ability of a computer program in an electronic device to emulate (or imitate) another program or device. Many printer (computing), printers, for example, are designed to emulate Hewlett-Packard, HP LaserJet printers because a significant amount of software is written specifically for HP models. If a non-HP printer emulates an HP printer, any software designed for an actual HP printer will also function on the non-HP device, producing equivalent print results. Since at least the 1990s, many video game enthusiasts and hobbyists have used emulators to play classic arcade games from the 1980s using the games' original 1980s machine code and data, which is in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Of The ACM
''Communications of the ACM'' (''CACM'') is the monthly journal of the Association for Computing Machinery (ACM). History It was established in 1958, with Saul Rosen as its first managing editor. It is sent to all ACM members. Articles are intended for readers with backgrounds in all areas of computer science and information systems. The focus is on the practical implications of advances in information technology and associated management issues; ACM also publishes a variety of more theoretical journals. The magazine straddles the boundary of a science magazine, trade magazine, and a scientific journal. While the content is subject to peer review, the articles published are often summaries of research that may also be published elsewhere. Material published must be accessible and relevant to a broad readership. From 1960 onward, ''CACM'' also published algorithms, expressed in ALGOL. The collection of algorithms later became known as the Collected Algorithms of the ACM. CA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floating-point Arithmetic
In computing, floating-point arithmetic (FP) is arithmetic on subsets of real numbers formed by a ''significand'' (a Sign (mathematics), signed sequence of a fixed number of digits in some Radix, base) multiplied by an integer power of that base. Numbers of this form are called floating-point numbers. For example, the number 2469/200 is a floating-point number in base ten with five digits: 2469/200 = 12.345 = \! \underbrace_\text \! \times \! \underbrace_\text\!\!\!\!\!\!\!\overbrace^ However, 7716/625 = 12.3456 is not a floating-point number in base ten with five digits—it needs six digits. The nearest floating-point number with only five digits is 12.346. And 1/3 = 0.3333… is not a floating-point number in base ten with any finite number of digits. In practice, most floating-point systems use Binary number, base two, though base ten (decimal floating point) is also common. Floating-point arithmetic operations, such as addition and division, approximate the correspond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Packed Decimal
In computing and electronic systems, binary-coded decimal (BCD) is a class of binary encodings of decimal numbers where each digit is represented by a fixed number of bits, usually four or eight. Sometimes, special bit patterns are used for a sign or other indications (e.g. error or overflow). In byte-oriented systems (i.e. most modern computers), the term ''unpacked'' BCD usually implies a full byte for each digit (often including a sign), whereas ''packed'' BCD typically encodes two digits within a single byte by taking advantage of the fact that four bits are enough to represent the range 0 to 9. The precise four-bit encoding, however, may vary for technical reasons (e.g. Excess-3). The ten states representing a BCD digit are sometimes called '' tetrades'' (the nibble typically needed to hold them is also known as a tetrade) while the unused, don't care-states are named ''pseudo-tetrad(e)s'', ''pseudo-decimals'', or ''pseudo-decimal digits''. BCD's main virtue, in comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/370 Model 165
The IBM System/370 Model 165 (and the Model 155) were jointly announced June 30, 1970 as "designed for ... the Seventies." That same day IBM announced the 370/195. They were the first three models of the IBM System/370 line of computers. Since none of them came with virtual memory, "which was to be a hallmark of the 370 line", some said about these early members of the IBM System/370 family, especially about the 165 and 155, that they were not "the real 370 line." Three months later a fourth IBM System/370, the Model 145, was announced. Virtual memory The initially announced System/370 Models 165 and 155 systems did not support virtual memory. In 1972 an upgrade option was announced "to provide the hardware necessary to operate in a virtual memory mode." Unlike the IBM System/370 Model 145, which as early as June 1971 included the hardware necessary to support virtual memory, and for which a microcode update from a floppy disk, adding support for virtual memory, was announc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/370 Model 155
The IBM System/370 Model 155 (and the IBM System/370 Model 165, Model 165) were jointly announced Jun 30, 1970 as "designed for ... the Seventies." That same day IBM announced the 370/195. They were the first three models of the IBM System/370 line of computers. Since none of them came with virtual memory, "which was to be a hallmark of the 370 line", some said about these early members of the IBM System/370 family, especially about the 155 and 165, that they were not "the real 370 line." Three months later a fourth IBM System/370, the IBM System/370 Model 145, Model 145, was announced. Virtual memory The initially announced System/370 Models 155 and 165 systems did not support virtual memory. In 1972 an upgrade option was announced "to provide the hardware necessary to operate in a virtual memory mode." Unlike the IBM System/370 Model 145, which as early as June 1971 included the hardware necessary to support virtual memory, and for which a microcode update from a floppy dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 3090
The IBM 3090 family is a family of mainframe computers that was a high-end successor to the IBM System/370 series, and thus indirectly the successor to the IBM System/360 launched 25 years earlier. Announced on 12 February 1985, the press releases did not explicitly mention that the two models, Model 200 and Model 400, were backwardly compatible with the 370; instead, they were simply positioned as replacements for the IBM 3033. The IBM 3090/200 version was rated at 18 MIPS and 31,000 UNIX Dhrystones. This was true of the entire line, which expanded with the release of the Model 120E, 150, 150E, 180, 180E, 200, 200E, 300, 300E, 400, 400E, 600E, 600J, and 600S 3090 were described as using "ideas from the ... IBM 3033, extending them ... It also took ... from the ... IBM 308X." The 400 and 600 were respectively two 200s or 300s coupled together as one system and could run in either single-system image mode or partitioned into two systems. Models and feature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM 9020
The IBM 9020 was an IBM System/360 computer adapted into a multiprocessor system for use by the U.S. Federal Aviation Administration, FAA for Air Traffic Control. Systems were installed in the FAA's 20 ''en route'' Air Route Traffic Control Centers (ARTCCs), beginning in the late 1960s. The U.K. UK Civil Aviation Authority, CAA also installed a system in its London Terminal Control Centre, London centre. The IBM 9020A, for example, was based on the IBM System/360 Model 50, S/360-50 and the 9020D used two out of three or four IBM System/360 Model 65, S/360-65 processors for flight and radar data processing with two out of three S/360-50 processors providing input/output capability. There were three operational variants of the 9020 system: 9020A CCC (Central Computer Complex); 9020D CCC; and 9020E DCC (Display Channel Complex). All the 9020A CCCs were attached to a non-IBM display complex, while the 9020D CCCs could be attached to either a non-IBM display complex or to the IBM 9020E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/360 Model 67
IBM mainframes are large computer systems produced by IBM since 1952. During the 1960s and 1970s, IBM dominated the computer market with the 7000 series and the later System/360, followed by the System/370. Current mainframe computers in IBM's line of business computers are developments of the basic design of the System/360. First and second generation From 1952 into the late 1960s, IBM manufactured and marketed several large computer models, known as the IBM 700/7000 series. The first-generation 700s were based on vacuum tubes, while the later, second-generation 7000s used transistors. These machines established IBM's dominance in electronic data processing ("EDP"). IBM had two model categories: one (701, 704, 709, 7030, 7090, 7094, 7040, 7044) for engineering and scientific use, and one (702, 705, 705-II, 705-III, 7080, 7070, 7072, 7074, 7010) for commercial or data processing use. The two categories, scientific and commercial, generally used common peripherals but had co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM System/360 Model 65
The IBM System/360 Model 65 is a member of the IBM System/360 family of computers. It was announced April 1965, and replaced two models, the Model 60 and Model 62, announced one year prior but never shipped. It was discontinued in March 1974. Models There are six submodels of the S/360-65. They vary by the amount of core memory with which the system is offered. The G65, H65, I65, IH65 and J65 submodels are configured with 128K, 256K, 512K, 768K or 1M of core memory, respectively. By 1974 the smallest ''G'' submodel had been discontinued. The MP (multiprocessor) model was added supporting from 512K to 2MB of system memory. The system can also attach IBM 2361 Large Capacity Storage (LCS) modules which provide up to 8MB of additional storage, however with a considerably slower memory cycle time of 8 microseconds compared to the 750 nanoseconds of processor storage. Relative performance The performance of the Model 65 is more than triple that of a S/360-50, whereas the Model 75, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
