 | |
 IBM System/360 Model 40 at the USDA | |
| Manufacturer | International Business Machines Corporation (IBM) |
|---|---|
| Product family | System/360 |
| Release date | April 7, 1964 |
| Discontinued | October 7, 1977 |
| Memory | 16–128 KB Core |
The IBM System/360 Model 40 was a mid-range member of the IBM System/360 family. It was announced on April 7, 1964, shipped in 1965, and withdrawn on October 7, 1977. [1] [2]
On April 7, 1964, IBM announced the IBM System/360, to be available in six models. [3] [4] [5] The 360/40 was first delivered in April 1965. [6]
The 360/30 and the 360/40 were the two largest revenue producing System/360 models, [7] accounting for over half of the units sold. [8]
Five models of the 360/40 were offered. [9] The D40, E40, F40, G40 and H40 were configured with 16K, 32K, 64K, 128K and 256K of core memory and correspondingly 16, 32, 64, 128 and 128 [NB 1] multiplexer subchannels. [9]
The H40 occupied "more floor space than the other models." [9] : p.5
| A typical, early, basic Model 40 system had the following configuration: [10] | |
|---|---|
| Model 40 processor | IBM 2040 Central Processing Unit *128 KB byte storage *storage protection feature *universal instruction set *one multiplexor channel *two selector channels *interval timer |
| Operator console | IBM 1052 Typewriter- Keyboard (usually assigned to 009 hexadecimal address) |
| Unit record device | IBM 1442 Card Reader-Punch (00A) or IBM 2540 Reader-Punch (00C & 00D) |
| Line printer | IBM 1443 Printer (00B) or IBM 1403 Printer (00E) |
| Disk storage | IBM 2311 Magnetic Disk Drives (190 & 191) or IBM 2314 Direct Access Storage Facility |
| Tape storage | IBM 2401 Magnetic Tape Units (180 & 181 for 7-track, and 182 & 183 for 9-track) |
| Telecommunications controller (If used in a telecommunications environment) | IBM 2701 Communication Controller |
Like most System/360 models the Model 40 was microprogrammed. The microcode was stored in transformer read-only storage (TROS), organized as up to 8192 words of 56 bits each. Standard microcode consisted of up to 4096 words. The additional 4096 words were used for the 1401 or 1410 compatibility feature. [11]
With the additional Compatibility Feature hardware and Compatibility Support software under DOS/360, the IBM 1401/1440/1460 object programs could be run in the emulation mode, with little or no reprogramming. [12]
Although the cover of IBM's MVT Guide [13] indicates that even a 360/40 could run MVT, the IBM operating system used was usually the realistically sized DOS/360,[ citation needed ] because all but one model of the 360/40 had less than MVT's minimum memory requirements of 256KB. [14] [15]
The IBM System/360 Model 40 was developed at IBM Hursley [16] and manufactured at IBM's facilities in: Poughkeepsie, U.S., Mainz, Germany; and Fujisawa, Japan. [17]
A modified Model 40 ran CP-40, the ancestor of CP/CMS, which in turn was the progenitor of the VM line.
IBM mainframes are large computer systems produced by IBM since 1952. During the 1960s and 1970s, IBM dominated the large computer market. Current mainframe computers in IBM's line of business computers are developments of the basic design of the IBM System/360.
In processor design, microcode is a technique that interposes an intermediate layer between the central processing unit (CPU) hardware and the programmer-visible instruction set architecture of a computer.
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 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.
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.
The IBM Time Sharing System TSS/360 is a discontinued early time-sharing operating system designed exclusively for a special model of the System/360 line of mainframes, the Model 67. Made available on a trial basis to a limited set of customers in 1967, it was never officially released as a supported product by IBM. TSS pioneered a number of novel features, some of which later appeared in more popular systems such as MVS. TSS was migrated to System/370 and 303x systems, but despite its many advances and novel capabilities, TSS failed to meet expectations and was eventually canceled. TSS/370 was used as the basis for a port of UNIX to the IBM mainframe. TSS/360 also inspired the development of the TSS/8 operating system.
The IBM System/360 Model 30 was a low-end member of the IBM System/360 family. It was announced on April 7, 1964, shipped in 1965, and withdrawn on October 7, 1977. The Model 30 was designed by IBM's General Systems Division in Endicott, New York, and manufactured in Endicott and other IBM manufacturing sites outside of U.S.
CP-40 was a research precursor to CP-67, which in turn was part of IBM's then-revolutionary CP[-67]/CMS – a virtual machine/virtual memory time-sharing operating system for the IBM System/360 Model 67, and the parent of IBM's VM family. CP-40 ran multiple instances of client operating systems – particularly CMS, the Cambridge Monitor System, built as part of the same effort. Like CP-67, CP-40 and the first version of CMS were developed by IBM's Cambridge Scientific Center (CSC) staff, working closely with MIT researchers at Project MAC and Lincoln Laboratory. CP-40/CMS production use began in January 1967. CP-40 ran on a unique, specially modified IBM System/360 Model 40.
The history of IBM mainframe operating systems is significant within the history of mainframe operating systems, because of IBM's long-standing position as the world's largest hardware supplier of mainframe computers. IBM mainframes run operating systems supplied by IBM and by third parties.
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB and Input/Output Control System (IOCS) packages for the IBM 7090/7094 and even more so by the PR155 Operating System for the IBM 1410/7010 processors. It was one of the earliest operating systems to require the computer hardware to include at least one direct access storage device.
System Generation (SysGen) is a two-stage process for installing or updating OS/360, OS/VS1, OS/VS2 (SVS), OS/VS2 (MVS) and chargeable systems derived from them. There are similar processes for, e.g., DOS/360, which this article does not cover. Also, some of the details have changed between releases of OS/360 and many details do not carry over to later systems.
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 Administrative Terminal System, also known as ATS/360, provided text- and data-management tools for working with documents to users of IBM System/360 systems.
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.
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.
The IBM System/360 Model 25 is a low-end member of the IBM System/360 family. It was announced on January 3, 1968, 3 years before the IBM System/360 Model 22, as a "bridge between its old and new computing systems".
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".
The IBM System/370 Model 165 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.
The IBM System/370 Model 135 was announced March 8, 1971, the only 370 introduced that year. The 135 was IBM's fifth System 370, and it was withdrawn October 16, 1979.
Mike Flinders, who also worked at Hursley where the 360/40 was designed
| Models |
|  | ||||
|---|---|---|---|---|---|---|
| Peripherals | ||||||
| Software | ||||||
| Innovations | ||||||
| Related | ||||||