IBM 2365 Processor Storage

Last updated

The IBM 2365 Processor Storage is a magnetic-core memory storage unit that is a component of the IBM System/360 models 65, [1] 67, [2] 75 [3] and 85 [4] computers, which were released between 1965 and 1968.

Contents

Storage is implemented using magnetic cores with a storage width of 72 bits, which comprise 64 data bits (8 bytes, or one doubleword) plus 8 parity bits. The IBM 2365 model 1 contains 131,072 (128 K) bytes of memory; all other models contain 262,144 (256 K) bytes. The model 2 could be converted in the field to a model 13.

All models other than the model 1 consist of two memory stacks. Addressing for the stacks is interleaved, so the first 64-bit word is in one stack, the second in the other stack, and so forth. This improves performance when doing sequential access.

All models other than the model 5 have a cycle time of 750 nanoseconds.

Models

The various models are used as follows:

Use with the System/360 model 85

The IBM 2365 model 5 is special because the System/360 model 85 accesses memory in 128-bit (16 byte) units, unlike the other System/360 models which support the IBM 2365, all of which access 64-bit (8 byte) units. On the System/360 model 85, the IBM 2365 model 5 operates with a cycle time of 1040 nanoseconds, and two or four of them are required. Because the System/360 model 85 CPU is so much faster than memory, if there are two IBM 2365 model 5 components they are two-way interleaved, and if there are four IBM 2365 model 5 components they are four-way interleaved. Because the IBM 2365 model 5 is internally two-way interleaved, sequential 128-bit memory operations issued by the System/360 model 85 CPU traverse all the memory components before cycling back to the first.

The IBM 2365 model 5 is used only with the System/360 model 85 with 524,288 (512 K) or 1,048,576 bytes (1 MB) of storage.

IBM 2385 Processor Storage

The IBM System/360 Model 85, when configured with 2,097,152 (2 MB, 360/85 K85) or 4,194,304 (4 MB, 360/85 L85) bytes, uses the IBM 2385 instead of the IBM 2365 Processor Storage. The IBM 2385 has a cycle time of 960 nanoseconds compared to 1,040 nanoseconds for the IBM 2365 model 5.

Related Research Articles

A control store is the part of a CPU's control unit that stores the CPU's microprogram. It is usually accessed by a microsequencer. A control store implementation whose contents are unalterable is known as a Read Only Memory (ROM) or Read Only Storage (ROS); one whose contents are alterable is known as a Writable Control Store (WCS).

<span class="mw-page-title-main">IBM System/360</span> IBM mainframe computer family (1964–1977)

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.

<span class="mw-page-title-main">IBM System/370</span> Family of mainframe computers 1970-1990

The IBM System/370 (S/370) is a model range of IBM mainframe computers announced on June 30, 1970, as the successors to the System/360 family. 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. In September 1990, the System/370 line was replaced with the System/390.

<span class="mw-page-title-main">UNIVAC 1100/2200 series</span> Family of mainframe computers

The UNIVAC 1100/2200 series is a series of compatible 36-bit computer systems, beginning with the UNIVAC 1107 in 1962, initially made by Sperry Rand. The series continues to be supported today by Unisys Corporation as the ClearPath Dorado Series. The solid-state 1107 model number was in the same sequence as the earlier vacuum-tube computers, but the early computers were not compatible with the solid-state successors.

In computing, channel I/O is a high-performance input/output (I/O) architecture that is implemented in various forms on a number of computer architectures, especially on mainframe computers. In the past, channels were generally implemented with custom devices, variously named channel, I/O processor, I/O controller, I/O synchronizer, or DMA controller.

<span class="mw-page-title-main">IBM System/360 Model 67</span> 1967 IBM mainframe model with virtual memory and 32-bit addressing

The IBM System/360 Model 67 (S/360-67) was an important IBM mainframe model in the late 1960s. Unlike the rest of the S/360 series, it included features to facilitate time-sharing applications, notably a Dynamic Address Translation unit, the "DAT box", to support virtual memory, 32-bit addressing and the 2846 Channel Controller to allow sharing channels between processors. The S/360-67 was otherwise compatible with the rest of the S/360 series.

<span class="mw-page-title-main">RCA Spectra 70</span>

The RCA Spectra 70 was a line of electronic data processing (EDP) equipment manufactured by the Radio Corporation of America’s computer division beginning in April 1965. The Spectra 70 line included several CPU models, various configurations of core memory, mass-storage devices, terminal equipment, and a variety of specialized interface equipment.

This timeline of binary prefixes lists events in the history of the evolution, development, and use of units of measure which are germane to the definition of the binary prefixes by the International Electrotechnical Commission (IEC) in 1998, used primarily with units of information such as the bit and the byte.

The DEC 7000 AXP and DEC 10000 AXP are a series of high-end multiprocessor server computers developed and manufactured by Digital Equipment Corporation, introduced on 10 November 1992. These systems formed part of the first generation of systems based on the 64-bit Alpha AXP architecture and at the time of introduction, ran Digital's OpenVMS AXP operating system, with DEC OSF/1 AXP available in March 1993. They were designed in parallel with the VAX 7000 and VAX 10000 minicomputers, and are identical except for the processor module(s) and supported bus interfaces. A field upgrade from a VAX 7000/10000 to a DEC 7000/10000 AXP was possible by means of swapping the processor boards.

The Challenge, code-named Eveready and Terminator, is a family of server computers and supercomputers developed and manufactured by Silicon Graphics in the early to mid-1990s that succeeded the earlier Power Series systems. The Challenge was later succeeded by the NUMAlink-based Origin 200 and Origin 2000 in 1996.

The IBM 2361 Large Capacity Storage (LCS) is an optional component of the IBM System/360 models 50, 65 (when not being used as a multiprocessor), and 75 computers. Storage is implemented using magnetic cores; the cycle time is 8 microseconds and the access time is 3.6 microseconds. This component is also called IBM 2361 Core Storage or IBM 2361 Large Core Storage. It provides additional main storage with a slower access time than the standard storage of the machine—for example its 8μsec compares to 750nsec for main storage on the Model 65.

The IBM System/360 architecture is the model independent architecture for the entire S/360 line of mainframe computers, including but not limited to the instruction set architecture. The elements of the architecture are documented in the IBM System/360 Principles of Operation and the IBM System/360 I/O Interface Channel to Control Unit Original Equipment Manufacturers' Information manuals.

<span class="mw-page-title-main">IBM System/360 Model 20</span> Low-end IBM computer model from 1960s

The IBM System/360 Model 20 is the smallest member of the IBM System/360 family announced in November 1964. The Model 20 supports only a subset of the System/360 instruction set, with binary numbers limited to 16 bits and no floating point. In later years it would have been classified as a 16-bit minicomputer rather than a mainframe, but the term "minicomputer" was not current, and in any case IBM wanted to emphasize the compatibility of the Model 20 rather than its differences from the rest of the System/360 line. It does, however, have the full System/360 decimal instruction set, that allows for addition, subtraction, product, and dividend of up to 31 decimal digits.

<span class="mw-page-title-main">IBM System/360 Model 50</span> Midrange IBM computer from 1960s

The IBM System/360 Model 50 is a member of the IBM System/360 family of computers. The Model 50 was announced in April 1964 with the other initial models of the family, and first shipped in August 1965 to the Bank of America.

<span class="mw-page-title-main">IBM System/360 Model 65</span> IBM computer model from 1960s

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.

<span class="mw-page-title-main">IBM System/360 Model 85</span> High-end IBM computer model from late 1960s

The IBM System/360 Model 85 is a high-end member of the System/360 family of computers, with many advanced features, and was announced in January 1968 and first shipped in December 1969. IBM built only about 30 360/85 systems because of "a recession in progress".

<span class="mw-page-title-main">IBM System/360 Model 75</span> High-end IBM computer model from 1960s

The IBM System/360 Model 75 is a discontinued high end/high performance system that was introduced on April 22, 1965. 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. Five Model 75 computers housed at NASA's Real Time Computer Complex were used during the Apollo program.

<span class="mw-page-title-main">IBM 303X</span>

The IBM 303X is a discontinued line of mainframe computers, the first model of which, the IBM 3033 Processor, nicknamed "The Big One", was introduced March 25, 1977.

<span class="mw-page-title-main">IBM System/360 Model 195</span> High-end IBM computer model from 1970s

The IBM System/360 Model 195 is a discontinued IBM computer introduced on August 20, 1969. The Model 195 was a reimplementation of the IBM System/360 Model 91 design using monolithic integrated circuits. It offers "an internal processing speed about twice as fast as the Model 85, the next most powerful System/360". The Model 195 was discontinued on February 9, 1977, the same date as the System/370 Model 195.

In addition to the drums used as main memory by IBM, e.g., IBM 305, IBM 650, IBM offered drum devices as secondary storage for the 700/7000 series and System/360 series of computers.

References

  1. IBM (September 1968), IBM System/360 Model 65 Functional Characteristics (PDF), Fourth Edition, A22-6884-3
  2. IBM (February 1972), IBM System/360 Model 67 Functional Characteristics (PDF), Third Edition, GA27-2719-2
  3. IBM, IBM System/360 Model 75 Functional Characteristics (PDF), A22-6889-0
  4. IBM (June 1968), IBM System/360 Model 85 Functional Characteristics (PDF), Second Edition, A22-6916-1