IBM System/360

System/360IBM 360IBM S/360S/360System 360IBMIBM 360 Model 30IBM 360/370/360 series360 model 65
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.wikipedia
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IBM

International Business MachinesIBM CorporationInternational Business Machines Corporation
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.
The IBM mainframe, exemplified by the System/360, was the dominant computing platform during the 1960s and 1970s.

IBM hexadecimal floating point

hexadecimalhexadecimal floating pointbase-16 excess-64 floating point format
All but the incompatible Model 44 and the most expensive systems used microcode to implement the instruction set, which featured 8-bit byte addressing and binary, decimal and (hexadecimal) floating-point calculations.
IBM System/360 computers, and subsequent machines based on that architecture (mainframes), support a hexadecimal floating-point format (HFP).

IBM System/360 Model 44

Model 44System/360 Model 44360/44
All but the incompatible Model 44 and the most expensive systems used microcode to implement the instruction set, which featured 8-bit byte addressing and binary, decimal and (hexadecimal) floating-point calculations.
The IBM System/360 Model 44 is a specialized variation of IBM's System 360 computer architecture designed for scientific computing, real-time computing, process control and Numerical Control (NC).

IBM System/360 Model 20

Model 20System/360 Model 2020
The least expensive model was the Model 20 with as little as 4096 bytes of core memory, eight 16-bit registers instead of the sixteen 32-bit registers of other System/360 models, and an instruction set that was a subset of that used by the rest of the range. Later additions to the low-end included models 20 (1966, mentioned above), 22 (1971), and 25 (1968).
The IBM System/360 Model 20 is the smallest member of the IBM System/360 family announced in November 1964.

Fred Brooks

Frederick P. Brooks, Jr.Brooks, Jr., Frederick P. Brooks, Fred
The chief architect of System/360 was Gene Amdahl, and the project was managed by Fred Brooks, responsible to Chairman Thomas J. Watson Jr. The commercial release was piloted by another of Watson's lieutenants, John R. Opel, who managed the launch of IBM’s System 360 mainframe family in 1964.
Frederick Phillips "Fred" Brooks Jr. (born April 19, 1931) is an American computer architect, software engineer, and computer scientist, best known for managing the development of IBM's System/360 family of computers and the OS/360 software support package, then later writing candidly about the process in his seminal book The Mythical Man-Month.

IBM 2361 Large Capacity Storage

IBM 2361Large Capacity Storage (LCS)
Up to 8 megabytes of slower (8 microsecond) Large Capacity Storage (LCS) was also available.
The IBM 2361 Large Capacity Storage is a component of the IBM System/360 models 50, 65 (when not being used as a multiprocessor), and 75 computers.

Computer architecture

architecturearchitecturescomputer design
The design made a clear distinction between architecture and implementation, allowing IBM to release a suite of compatible designs at different prices.
Brooks went on to help develop the IBM System/360 (now called the IBM zSeries) line of computers, in which “architecture” became a noun defining “what the user needs to know”.

IBM System/360 Model 40

Model 40360/4040
The initial announcement in 1964 included Models 30, 40, 50, 60, 62, and 70. The first three were low- to middle-range systems aimed at the IBM 1400 series market.
The IBM System/360 Model 40 was a mid-range member of the IBM System/360 family.

IBM System/360 Model 50

360/5050Model 50
The initial announcement in 1964 included Models 30, 40, 50, 60, 62, and 70. The first three were low- to middle-range systems aimed at the IBM 1400 series market.
The IBM System/360 Model 50 is a member of the IBM System/360 family of computers.

IBM System/360 Model 65

65360/65Model 65
The last three, intended to replace the 7000 series machines, never shipped and were replaced with the 65 and 75, which were first delivered in November 1965, and January 1966, respectively.
The IBM System/360 Model 65 is a member of the IBM System/360 family of computers.

Microcode

microprogrammicroprogrammedmicroprogramming
All but the incompatible Model 44 and the most expensive systems used microcode to implement the instruction set, which featured 8-bit byte addressing and binary, decimal and (hexadecimal) floating-point calculations.
Architectures with instruction sets implemented by complex microprograms included the IBM System/360 and Digital Equipment Corporation VAX.

IBM System/360 Model 91

360/9191System/360 Model 91
The 1967 IBM System/360 Model 91 could do up to 16.6 million instructions per second. A succession of high-end machines included the Model 67 (1966, mentioned below, briefly anticipated as the 64 and 66 ), 85 (1969), 91 (1967, anticipated as the 92), 95 (1968), and 195 (1971).
Functionally, the Model 91 ran like any other large-scale System/360, but the internal organization was the most advanced of the System/360 line, and it was the first IBM computer to support out-of-order instruction execution.

IBM System/360 Model 67

Model 67360/67S/360-67
A succession of high-end machines included the Model 67 (1966, mentioned below, briefly anticipated as the 64 and 66 ), 85 (1969), 91 (1967, anticipated as the 92), 95 (1968), and 195 (1971). The Model 67, announced in August 1965, was the first production IBM system to offer dynamic address translation (virtual memory) hardware to support time-sharing.
Unlike the rest of the S/360 series, it included features to facilitate time-sharing applications, notably a DAT box to support virtual memory and 32-bit addressing.

Instruction set architecture

instruction setinstructionsinstruction
The least expensive model was the Model 20 with as little as 4096 bytes of core memory, eight 16-bit registers instead of the sixteen 32-bit registers of other System/360 models, and an instruction set that was a subset of that used by the rest of the range.
The concept of an architecture, distinct from the design of a specific machine, was developed by Fred Brooks at IBM during the design phase of System/360.

IBM System/370

System/370S/370370
The 85 design was intermediate between the System/360 line and the follow-on System/370 and was the basis for the 370/165.
The IBM System/370 (S/370) was a model range of IBM mainframe computers announced on June 30, 1970 as the successors to the System/360 family.

IBM 700/7000 series

FAP7000 series7010
The last three, intended to replace the 7000 series machines, never shipped and were replaced with the 65 and 75, which were first delivered in November 1965, and January 1966, respectively.
The 7000s, in turn, were eventually replaced with System/360, which was announced in 1964.

Mainframe computer

mainframemainframesmainframe computers
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.
Since the late-1950s, mainframe designs have included subsidiary hardware (called channels or peripheral processors) which manage the I/O devices, leaving the CPU free to deal only with high-speed memory.

Gene Amdahl

AmdahlGene M. Amdahl, Ph.D.
The chief architect of System/360 was Gene Amdahl, and the project was managed by Fred Brooks, responsible to Chairman Thomas J. Watson Jr. The commercial release was piloted by another of Watson's lieutenants, John R. Opel, who managed the launch of IBM’s System 360 mainframe family in 1964.
On his return he became chief architect of IBM System/360 and was named an IBM Fellow in 1965, and head of the ACS Laboratory in Menlo Park, California.

IBM System/360 Model 22

22
Later additions to the low-end included models 20 (1966, mentioned above), 22 (1971), and 25 (1968).
The IBM System/360 Model 22 was an IBM mainframe from the System/360 line.

Time-sharing

timesharingtime sharingtime-sharing system
The Model 67, announced in August 1965, was the first production IBM system to offer dynamic address translation (virtual memory) hardware to support time-sharing.
Common systems used for time-sharing included the SDS 940, the PDP-10, and the IBM 360.

IBM System/360 Model 75

360/7575
The last three, intended to replace the 7000 series machines, never shipped and were replaced with the 65 and 75, which were first delivered in November 1965, and January 1966, respectively.
Although it played many roles in IBM's System/360 lineup, it accounted for a small fraction of a percent of the 360 systems sold.

Amdahl Corporation

AmdahlAmdahl CorpAmdahl Corp.
Computers that were mostly identical or compatible in terms of the machine code or architecture of the System/360 included Amdahl's 470 family (and its successors), Hitachi mainframes, the UNIVAC 9000 series, Fujitsu as the Facom, the RCA Spectra 70 series, and the English Electric System 4.
Founded in 1970 by Gene Amdahl, a former IBM computer engineer best known as chief architect of System/360, it has been a wholly owned subsidiary of Fujitsu since 1997.

RCA Spectra 70

Spectra 70SpectraSpectra series
Computers that were mostly identical or compatible in terms of the machine code or architecture of the System/360 included Amdahl's 470 family (and its successors), Hitachi mainframes, the UNIVAC 9000 series, Fujitsu as the Facom, the RCA Spectra 70 series, and the English Electric System 4.
The system architecture and instruction-set were largely compatible with the non-privileged instruction-set of the IBM System/360.

IBM Z

zSeriesSystem zz900
Application-level compatibility (with some restrictions) for System/360 software is maintained to the present day with the System z mainframe servers.
In effect, current systems are the direct, lineal descendants of System/360, announced in 1964, and the System/370 from the 1970s.

ES EVM

EC-1046Edinaya SistemaES-1022 and ES-1035
RCA sold the Spectra series to what was then UNIVAC, where they became the UNIVAC Series 70. UNIVAC also developed the UNIVAC Series 90 as successors to the 9000 series and Series 70. The Soviet Union produced a System/360 clone named the ES EVM.
ES EVM (ЕС ЭВМ, Единая система электронных вычислительных машин, Yedinaya Sistema Electronnykh Vytchislitel'nykh Mashin, meaning "Unified System of Electronic Computers") was a series of clones of IBM's System/360 and System/370 mainframes, released in the Comecon countries under the initiative of the Soviet Union since the 1960s.