IBM 3790

Last updated
IBM 3790 Communication System
IBM logo.svg
Release date1974;48 years ago (1974)
Successor IBM 8100

The IBM 3790 Communications System, developed by IBM's Data Processing Division (DPD), was announced in 1974. [1] It was one of the first distributed computing platforms. The 3790 preceded the IBM 8100, announced in 1979. [2] [3]

Contents

It was designed to be installed in branch offices, stores, subsidiaries, etc., and to be connected to the central host mainframe, using IBM Systems Network Architecture (SNA).

Although its successor's role in distributed data processing was said to be "a turning point in the general direction of worldwide computer development," the 3790 was described by Datamation in March 1979 as "less than successful." [2]

System description

IBM described it [4] as "a programmable, operator oriented terminal system."

Components

The 3790 supported [4]

The base unit of the 3790 was the IBM 3791 programmable control unit, which was offered as a choice of:

Attached to the 3791 were:

  • up to two dial-in IBM 2741 communications terminals,
  • up to four 3793 display stations, and a line printer.
  • The 3793 printer-keyboard (up to four).
  • The 3411 model 1, Magnetic tape unit and controller (added in 1977) and
  • up to three 3410 tape units attached to the 3411 unit.

Host software

Reception

The 3790 failed to achieve the success IBM intended, due to several issues. [2] It had a complex programming language, The 3790 Macro Assembler, and the customers found it difficult to deploy applications on it. The Macro Assembler ran only on an IBM mainframe and then the compiled and linked object was moved to the 3790 for testing.

The 3790 was designed as a departmental processor, but the requirement for an IBM mainframe development environment inhibited adoption in its target market of mid-size companies. The result was lackluster interest in the product. In addition the 3790 was priced higher than minicomputers of comparable processing power[ citation needed ].

One of the products IBM released to help developers was Program Validation Services (PVS). [5] With PVS, one could test a program in the mainframe environment using scripts. The scripts were cumbersome to create, and prone to errors. Since mainframe time was expensive and often difficult to obtain very few programmers used PVS for anything other than initial testing.

The manual for the Macro Assembler was bulky (about 4 inches thick) and difficult to use as a reference. Another programming issue was code design and size; the hardware architecture loaded code into memory on 2k segments, for optimal execution time it was critical to ensure that processing intensive loops did not cross the segment boundary and incur delays swapping segments in and out of memory.

IBM recognized the problems with the Macro Assembler and created an automated program generator named DMS. DMS later became Cross System Product (CSP) on the 8100. DMS was essentially a screen painter; it could do simple edits such as field range checking or numeric tests but more complex logic still had to be coded using the Macro Assembler.

IBM 3730

The IBM 3730 is a word-processing variant of the 3790, announced in the late 1970s. [6] It used 3790 hardware but its software made it a dedicated shared-logic word-processing system which could support a dozen or more word-processing IBM 3732 terminals, which were derived from the IBM 3270 family of terminals. Defunct IBM 3777 terminals which had been returned by customers were re-engineered and equipped with a specialized word-processing keyboard, and shipped back to other customers as part of the 3730 word processing system. The 3730 could be connected using Systems Network Architecture to a central mainframe running IBM DISOSS which was a centralized document exchange software running on CICS.

Related Research Articles

<span class="mw-page-title-main">IBM 3270</span> Family of block-oriented display terminals and printers made by IBM

The IBM 3270 is a family of block oriented display and printer computer terminals introduced by IBM in 1971 and normally used to communicate with IBM mainframes. The 3270 was the successor to the IBM 2260 display terminal. Due to the text color on the original models, these terminals are informally known as green screen terminals. Unlike a character-oriented terminal, the 3270 minimizes the number of I/O interrupts required by transferring large blocks of data known as data streams, and uses a high speed proprietary communications interface, using coaxial cable.

A direct-access storage device (DASD) is a secondary storage device in which "each physical record has a discrete location and a unique address". The term was coined by IBM to describe devices that allowed random access to data, the main examples being drum memory and hard disk drives. Later, optical disc drives and flash memory units are also classified as DASD.

Systems Network Architecture (SNA) is IBM's proprietary networking architecture, created in 1974. It is a complete protocol stack for interconnecting computers and their resources. SNA describes formats and protocols but, in itself, is not a piece of software. The implementation of SNA takes the form of various communications packages, most notably Virtual Telecommunications Access Method (VTAM), the mainframe software package for SNA communications.

<span class="mw-page-title-main">IBM Series/1</span> 1970s era IBM minicomputer

The IBM Series/1 is a 16-bit minicomputer, introduced in 1976, that in many respects competed with other minicomputers of the time, such as the PDP-11 from Digital Equipment Corporation and similar offerings from Data General and HP. The Series/1 was typically used to control and operate external electro-mechanical components while also allowing for primitive data storage and handling.

<span class="mw-page-title-main">CICS</span> IBM mainframe transaction monitor

IBM CICS is a family of mixed-language application servers that provide online transaction management and connectivity for applications on IBM mainframe systems under z/OS and z/VSE.

<span class="mw-page-title-main">IBM 8100</span>

The IBM 8100 Information System, announced Oct. 3, 1978, was at one time IBM’s principal distributed processing engine, providing local processing capability under two incompatible operating systems and was a follow-on to the IBM 3790.

DPCX was an operating system for the IBM 8100 small computer system. IBM hoped it would help their installed base of IBM 3790 customers migrate to the 8100 and the DPPX operating system. It was mainly deployed to support a word processing system, Distributed Office Support Facility (DOSF) which was derived from the earlier IBM 3730 word processing system.

Remote job entry is the procedure for sending requests for non-interactive data processing tasks (jobs) to mainframe computers from remote workstations, and by extension the process of receiving the output from such jobs at a remote workstation.

<span class="mw-page-title-main">IBM Displaywriter System</span>

The IBM 6580 Displaywriter System is a 16-bit microcomputer that was marketed and sold by IBM's Office Products Division primarily as a word processor. Announced in June 1980 and effectively withdrawn from marketing in July 1986, the system was sold with a 5 MHz Intel 8086, 128K to 448K of RAM, a swivel-mounted monochrome CRT monitor, a detached keyboard, a detached 8" floppy disk drive enclosure with one or two drives, and a detached daisy wheel printer, or Selectric printer. The primary operating system for the Displaywriter is IBM's internally developed word processing software titled "Textpack", but UCSD p-System, CP/M-86 and MS-DOS were also offered by IBM, Digital Research and CompuSystems, respectively.

Since the rise of the personal computer in the 1980s, IBM and other vendors have created PC-based IBM-compatible mainframes which are compatible with the larger IBM mainframe computers. For a period of time PC-based mainframe-compatible systems had a lower price and did not require as much electricity or floor space. However, they sacrificed performance and were not as dependable as mainframe-class hardware. These products have been popular with mainframe developers, in education and training settings, for very small companies with non-critical processing, and in certain disaster relief roles.

Queued Telecommunications Access Method (QTAM) is an IBM System/360 communications access method incorporating built-in queuing. QTAM was an alternative to the lower level Basic Telecommunications Access Method (BTAM).

Basic Assembly Language (BAL) is the commonly used term for a low-level programming language used on IBM System/360 and successor mainframes. Originally, "Basic Assembly Language" applied only to an extremely restricted dialect designed to run under control of IBM Basic Programming Support (BPS/360) on systems with only 8 KB of main memory, and only a card reader, a card punch, and a printer for input/output — thus the word "Basic". However, the full name and the initialism "BAL" almost immediately attached themselves in popular use to all assembly-language dialects on the System/360 and its descendants. BAL for BPS/360 was introduced with the System/360 in 1964.

<span class="mw-page-title-main">IBM 3270 PC</span>

The IBM 3270 PC, released in October 1983, is an IBM PC XT containing additional hardware that, in combination with software, can emulate the behaviour of an IBM 3270 terminal. It can therefore be used both as a standalone computer, and as a terminal to a mainframe.

The IBM 2780 and the IBM 3780 are devices developed by IBM to perform remote job entry (RJE) and other batch functions over telephone lines; they communicate with the mainframe via Binary Synchronous Communications and replaced older terminals using synchronous transmit-receive (STR). In addition, IBM has developed workstation programs for the 1130, 360/20, 2922, System/360 other than 360/20, System/370 and System/3.

Telecommunications Access Method (TCAM) is an access method, in IBM's OS/360 and successors computer operating systems on IBM System/360 and later, that provides access to terminals units within a teleprocessing network.

<span class="mw-page-title-main">IBM 3767</span>

IBM 3767 Communication Terminal is a serial printer terminal that employed dot matrix print-head technology and, for the first time, the Synchronous Data Link Control (SDLC) communications protocol set under IBM's Systems Network Architecture (SNA). It was introduced in 1974 and was used widely during the late 1970s to 1990s, for attachment to IBM System/360 and System/370 mainframe computers and IBM System/7 as an alternative to a 2741 typewriter terminal.

The IBM Kanji System was announced in 1971 to support Japanese language processing on the IBM System/360 computers. It was later enhanced by the support of IBM System/34, IBM 5550 and DOS/V.

CP-6 is a discontinued computer operating system, developed by Honeywell, Inc. in 1976, which was a backward-compatible work-alike of the Xerox CP-V fully rewritten for Honeywell Level/66 hardware. CP-6 was a command line oriented system. A terminal emulator allowed use of PCs as CP-6 terminals.

Distributed data processing (DDP) was the term that IBM used for the IBM 3790 (1975) and its successor, the IBM 8100 (1979). Datamation described the 3790 in March 1979 as "less than successful."

References

  1. ↑ "New products". Computer. 7 (2): 52–56. February 1974. doi:10.1109/MC.1974.6323458. ISSN   0018-9162.
  2. 1 2 3 Woods, Larry (March 1979). "IBM's 8100: First Impressions". Datamation.
  3. ↑ "(which can simulate 3790 functions through the DPCX operating system)"
  4. 1 2 3 "IBM 3790 Communications System" (PDF).
  5. ↑ Ronald A. Frank (July 16, 1975). "The 3790: A Glimpse Into IBM's Future Plans?". Computerworld. Vol. 9, no. 29. IDG Enterprise. p. 15. ISSN   0010-4841.
  6. ↑ E. Drake Lundell Jr. (16 October 1978). "IBM Introduces Office and Plant Systems". Computerworld. Vol. 12, no. 42. IDG Enterprise. p. 55. ISSN   0010-4841.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.