Digital Equipment Corporation

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Digital Equipment Corporation
Industry Computer manufacturing
Fate Assets were sold to various companies. What remained was sold to Compaq.
Successor Hewlett-Packard
(2002-Present)
Compaq
(1998-2002)
Founded 1957
Defunct 1998
Headquarters Maynard, Massachusetts
 United States
Key people Ken Olsen (founder, president, and chairman)
Harlan Anderson (co-founder)
Products PDP
VAX
DEC Alpha
Employees over 140,000 (1987)

Digital Equipment Corporation was a pioneering American computer company, a leading vendor in the minicomputer market though the 1960s and 1970s, and for a long time one of the most admired within the hacker community.

Initially focusing on the small-end of the computer market allowed DEC to grow without its potential competitors noticing, or caring enough to make serious efforts to compete with them. Their PDP series of machines became runaway best-sellers in the 1960s, especially the PDP-8, widely considered to be the first successful minicomputer. Looking to simplify and update their line, DEC replaced most of their smaller machines with the PDP-11 in 1970, eventually selling over 600,000 examples and cementing DECs position as one of the most innovative and successful companies in the industry.

Originally designed as a follow-on to the PDP-11, DEC's VAX-11 series was the first widely-used 32-bit minicomputer. Machines of this sort, known as "superminis", were able to compete in many roles with larger mainframes like the IBM System/370. The VAX was a runaway best-seller, with over 400,000 sold, and its sales through the 1980s propelled the company into the second largest in the industry as their systems stole billions in sales from formerly larger competitors. At its peak, DEC was the second largest employer in Massachusetts, second only to the state government.

The rapid rise of the business microcomputer in the late 1980s, and especially the introduction of powerful 32-bit systems in the 1990s, quickly eroded the value of DEC's systems. Network storage was another area that the company focused on in the early 1990s, but rapid progress in cost and storage capacity of hard drives eroded this lead even more rapidly. By the mid-90's, commodity machines offered performance and capacity comparable to DEC's largest systems. The company never came up with an appropriate response to these threats, and by the mid 1990s was a shell of its former self.

DEC's last major attempt to find a space in the rapidly changing market was the DEC Alpha, a series of 64-bit RISC CPUs. DEC initially started work on these designs as a way to re-implement their VAX series, in the same fashion that IBM was successfully selling mainframes based on their own POWER CPUs. Alpha systems could also be scaled downwards to deliver the fastest workstations on the market, at a competitive price. Although the Alpha systems met both of these goals, and was, for most of its lifetime, the fastest CPU on the market, it did little to effect the bottom line or repair the company's status.

The company was acquired in June 1998 by Compaq, in what was at that time the largest merger in the history of the computer industry. At the time, Compaq was focused on the enterprise market and had recently purchased several other large vendors. DEC was a major player overseas where Compaq had less presence. However, Compaq had little idea what to do with its acquisitions, and soon found itself in financial difficulty of its own. The company subsequently merged with Hewlett-Packard in May 2002. As of 2007^[update] its product lines were still produced under the HP name.

The company is often referred to within the computing industry as DEC (this acronym was frequently officially used by Digital itself, but the trademark was always DIGITAL).[1] Digital Equipment Corporation should not be confused with Digital Research; the two were unrelated, separate entities; or with Western Digital (despite the fact that they made the LSI-11 chipsets used in Digital Equipment Corporation's low end PDP-11/03 computers). Note, however, that there were Digital Research Laboratories where DEC did its corporate research.

History

Origins

Ken Olsen and Harlan Anderson were two engineers who had been working at MIT Lincoln Laboratory on the lab's various computer projects. The Lab is best known for their work on what would today be known as "interactivity", and their machines were among the first where operators had direct control over programs running in real-time. These had started in 1944 with the famed Whirlwind which was originally developed to make a flight simulator for the US Navy, although this was never completed.[2] Instead, this effort evolved into the SAGE system for the US Air Force, which used large screens and light guns to allow operators to interact with radar data stored in the computer.[3]

When the Air Force project wound down, the Lab turned their attention to an effort to build a version of the Whirlwind using transistors in place of vacuum tubes. In order to test their new circuitry, they first built a small 18-bit machine known as TX-0 which first ran in 1956.[4] When the TX-0 successfully proved the basic concepts, attention turned to a much larger system, the 36-bit TX-2 with a then-enormous 64 kWords of core memory. Core was so expensive that parts of TX-0's memory were stripped for the TX-2, and what remained of the TX-0 was then given to MIT on permanent loan.[5]

At MIT, Olsen and Anderson noticed something odd: students would line up for hours to get a turn to use the stripped-down TX-0, while largely ignoring a faster IBM machine that was also available. The two decided that the draw of interactive computing was so strong that they felt there was a market for a small machine dedicated to this role, essentially a commercialized TX-0. They could sell this to users where graphical output or realtime operation would be more important than outright performance. Additionally, as the machine would cost much less than the larger systems then available, it would also be able to serve users that needed a lower-cost solution dedicated to a specific task, where a larger 36-bit machine wouldn't be needed.[6]

In 1957 when the pair and Ken's brother Stan went looking for capital, they found that the American business community was hostile to investing in computer companies. Many smaller computer companies had come and gone in the 1950s, wiped out when new technical developments rendered their platforms obsolete, and even large companies like RCA and General Electric were failing to make a profit in the market. The only serious expression of interest came from Georges Doriot and his American Research and Development Corporation (AR&D). Worried that a new computer company would find it difficult to arrange further financing, Doriot suggested the fledgling company change its business plan to focus less on computers, and even change their name from "Digital Computer Corporation".[6]

The pair returned with an updated business plan that outlined two-phases for the company's development. They would start by selling computer modules as stand-alone devices that could be purchased separately and wired together to produce a number of different digital systems for lab use. Then, if these "digital modules" were able to build a self-sustaining business, the company would be free to use them to develop a complete computer in their Phase II.[7] The newly christened DEC received $70,000 from AR&D for a 70% share of the company,[6] and began operations in a Civil War era textile mill in Maynard, Massachusetts, where plenty of inexpensive manufacturing space was available.

Digital modules

In early 1958 DEC shipped its first products, the "Digital Laboratory Module" line. The Modules consisted of a number of individual electronic components and germanium transistors mounted to a circuit board, the actual circuits being based on those from the TX-2.[8]

The Laboratory Module were packaged in an extruded aluminum housing,[9] intended to sit on an engineer's workbench. They were then connected together using banana plug patch cords inserted at the front of the modules. Three versions were offered, running at 5 MHz (1957), 500 kHz (1959), or 10 MHz (1960).[8] The Modules proved to be in high demand in other computer companies, who used them to build equipment to test their own systems. Despite the recession of the late 1950s, the company sold $94,000 worth of these modules during 1958 alone, turning a profit at the end of its first year.[6]

The original Laboratory Modules were soon supplemented with the "Digital Systems Module" line, which were identical internally but packaged differently. The Systems Modules were designed with all of the connections at the back of the module using 22-pin Amphenol connectors, and were attached to each other by inserting them into a custom 19-inch rack. These versions allowed 25 modules be to inserted into a single 5-1/4 inch section of racking, and allowed the high densities needed to build a computer.[8] DEC used the Systems Modules to build their "Memory Test" machine for testing core memory systems, selling about 50 of these pre-packaged units over the next eight years.[10]

Modules were part of DEC's product line into the 1970s, although they went through several evolutions during this time as technology changed. The same circuits were then packaged as the first "R" (red) series "Flip-Chip" modules. Later, other module series provided additional speed, much higher logic density, and industrial I/O capabilities.[11] Digital published extensive data about the modules in free catalogs that became very popular.

PDP-1 family

With the company established and a successful product on the market, DEC turned its attention to the computer market once again as part of its planned "Phase II".[7] In August 1959, Ben Gurley started design of the company's first computer, the PDP-1. In keeping with Doriot's instructions, the name was an initialism for "Programmable Data Processor", leaving off the term "computer". As Gurley put it, "We aren't building computers, we're building 'Programmable Data Processors'." The prototype was first shown publically at the Joint Computer Conference in Boston in December 1959.[12]

The PDP-1 design was based on a number of System Building Blocks packaged into several 19-inch racks to form an 18-bit word computer, supplied standard with 4 kWords of core memory and running at a basic speed of 100,000 operations per second. The racks were themselves packaged into a single large mainframe case, with a hexagonal control panel containing switches and lights mounted to lay at table-top height at one end of the mainframe. Above the control panel was the system's standard input/output solution, a punch tape reader and writer. Most systems were purchased with two peripherals, the Type 30 vector graphics display, and a Soroban Engineering modified IBM Model B Electric typewriter that was used as a printer. The Soroban system was notoriously unreliable, and often replaced with a modified Friden Flexowriter, which also contained its own punch tape system. A variety of more-expensive add-ons followed, including magnetic tape systems, punch card readers and writers, and faster punch tape and printer systems.