Last updated Original Digital Equipment Corporation logo designed by Elliot Hendrickson in 1957.
Digital Equipment Corporation (DEC), was a major American company in the computer industry. Founded in 1957 with $70,000 of venture capital,[2] it became "the nation's second-largest computer company, after IBM."[3] Its initial major impact was in minicomputers, but its later-introduced VAX and Alpha systems are still notable.[4]
DEC was acquired in June 1998 by Compaq, in what was at that time the largest merger in the history of the computer industry.[5] Not long thereafter, Hewlett-Packard bought Compaq, "creating a technology company second in revenue only to IBM."[6]
Aside from the company's extensive hardware and software accomplishments, it was also noteworthy for its use of Matrix management[7]
Origins
DEC was headquartered at a former wool mill in Maynard, Massachusetts, from 1957 until 1992
Ken Olsen and Harlan Anderson were two engineers who had been working at MITLincoln Laboratory[8] 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.[9] 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.[10]
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.[11] When the TX-0 successfully proved the basic concepts, attention turned to a much larger system, the 36-bitTX-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.[12]
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 real-time 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 would not be needed.[13][dead link][bettersourceneeded]
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".[13][dead link][bettersourceneeded]
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.[14] The newly christened "Digital Equipment Corporation" received $70,000 from AR&D for a 70% share of the company,[13][dead link][bettersourceneeded] and began operations in a Civil War era textile mill in Maynard, Massachusetts, where plenty of inexpensive manufacturing space was available.
Digital modules
System Building Blocks (System Module) 1103 hex-inverter card (both sides)PDP-1 System Building Block #4106, circa 1963 - note that one transistor (yellow) has been replaced
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.[15]
The Laboratory Modules were packaged in an extruded aluminum housing,[16] intended to sit on an engineer's workbench, although a rack-mount bay was sold that held nine laboratory modules.[17] They were then connected together using banana plugpatch cords inserted at the front of the modules. Three versions were offered, running at 5MHz (1957), 500kHz (1959), or 10MHz (1960).[18] 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 (equivalent to $882,900in 2021), turning a profit at the end of its first year.[13][dead link][bettersourceneeded]
The original Laboratory Modules were soon supplemented with the "Digital System 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 plugging them into a backplane that could be mounted in a 19-inch rack. The backplanes allowed 25 modules in a single 5-1/4inch section of rack, and allowed the high densities needed to build a computer.[15]
The original laboratory and system module lines were offered in 500 kilocycle, 5 megacycle and 10 megacycle versions. In all cases, the supply voltages were -15 and +10 volts, with logic levels of -3 volts (passive pull-down) and 0 volts (active pull-up).[17]
DEC used the System 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.[19] The PDP-1 and LINC computers were also built using System Modules (see below).
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 Flip-Chip module series provided additional speed, much higher logic density, and industrial I/O capabilities.[20] DEC published extensive data about the modules in free catalogs that became very popular.
A PDP-1 system, with Steve Russell, developer of Spacewar! at the console. This is a canonical example of the PDP-1, with the console typewriter on the left, CPU and main control panel in the center, the Type 30 display on the right.
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".[14] 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 publicly at the Joint Computer Conference in Boston in December 1959.[21] The first PDP-1 was delivered to Bolt, Beranek and Newman in November 1960,[22] and formally accepted the next April.[23] The PDP-1 sold in basic form for $120,000 (equivalent to $8,243,757in 2021).[24] By the time production ended in 1969, 53 PDP-1s had been delivered.[19][25]
The PDP-1 was supplied standard with 4096 words of core memory, 18-bits per word, and ran at a basic speed of 100,000 operations per second. It was constructed using many System Building Blocks that were packaged into several 19-inch racks. The racks were themselves packaged into a single large mainframe case, with a hexagonal control panel containing switches and lights mounted to lie at table-top height at one end of the mainframe. Above the control panel was the system's standard input/output solution, a punched 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 punched tape system. A variety of more-expensive add-ons followed, including magnetic tape systems, punched card readers and punches, and faster punched tape and printer systems.
When DEC introduced the PDP-1, they also mentioned larger machines at 24, 30 and 36 bits, based on the same design.[26] During construction of the prototype PDP-1, some design work was carried out on a 24-bit PDP-2, and the 36-bit PDP-3. Although the PDP-2 never proceeded beyond the initial design, the PDP-3 found some interest and was designed in full.[27] Only one PDP-3 appears to have been built, in 1960, by the CIA's Scientific Engineering Institute (SEI) in Waltham, Massachusetts. According to the limited information available, they used it to process radar cross section data for the Lockheed A-12reconnaissance aircraft. Gordon Bell remembered that it was being used in Oregon some time later, but could not recall who was using it.[28]
In November 1962, DEC introduced the $65,000 PDP-4. The PDP-4 was similar to the PDP-1 and used a similar instruction set, but used slower memory and different packaging to lower the price. Like the PDP-1, about 54 PDP-4's were eventually sold, most to a customer base similar to the original PDP-1.[29]
In 1964, DEC introduced its new Flip Chip module design, and used it to re-implement the PDP-4 as the PDP-7. The PDP-7 was introduced in December 1964, and about 120 were eventually produced.[30] An upgrade to the Flip Chip led to the R series, which in turn led to the PDP-7A in 1965.[31] The PDP-7 is most famous as the original machine for the Unix operating system,[32] and until the Interdata 8/32 Unix only ran on DEC systems.[33]
A more dramatic upgrade to the PDP-1 series was introduced in August 1966, the PDP-9.[34] The PDP-9 was instruction-compatible with the PDP-4 and −7, but ran about twice as fast as the −7 and was intended to be used in larger deployments. At only $19,900 in 1968,[35] the PDP-9 was a big seller, eventually selling 445 machines, more than all of the earlier models combined.[36]
Even while the PDP-9 was being introduced, its replacement was being designed, and was introduced as 1969's PDP-15, which re-implemented the PDP-9 using integrated circuits in place of modules. Much faster than the PDP-9 even in basic form, the PDP-15 also included a floating point unit and a separate input/output processor for further performance gains. Over 400 PDP-15's were ordered in the first eight months of production, and production eventually amounted to 790 examples in 12 basic models.[36] However, by this time other machines in DEC's lineup could fill the same niche at even lower price points, and the PDP-15 would be the last of the 18-bit series.
A PDP-8 on display at the Smithsonian's National Museum of American History in Washington, D.C. This example is from the first generation of PDP-8s, built with discrete transistors and later known as the Straight 8.
In 1962, Lincoln Laboratory used a selection of System Building Blocks to implement a small 12-bit machine, and attached it to a variety of analog-to-digital (A to D) input/output (I/O) devices that made it easy to interface with various analog lab equipment. The LINC proved to attract intense interest in the scientific community, and has since been referred to as the first real minicomputer,[37] a machine that was small and inexpensive enough to be dedicated to a single task even in a small lab.
Seeing the success of the LINC, in 1963 DEC took the basic logic design but stripped away the extensive A to D systems to produce the PDP-5. The new machine, the first outside the PDP-1 mould, was introduced at WESTCON on 11 August 1963. A 1964 ad expressed the main advantage of the PDP-5, "Now you can own the PDP-5 computer for what a core memory alone used to cost: $27,000"[38] 116 PDP-5s were produced until the lines were shut down in early 1967. Like the PDP-1 before it, the PDP-5 inspired a series of newer models based on the same basic design that would go on to be more famous than its parent.
On 22 March 1965, DEC introduced the PDP-8, which replaced the PDP-5's modules with the new R-series modules using Flip Chips. The machine was re-packaged into a small tabletop case, which remains distinctive for its use of smoked plastic over the CPU which allowed one to easily see the wire-wrapped internals of the CPU. Sold standard with 4 kWords of 12-bit core memory and a Teletype Model 33 ASR for basic input/output, the machine listed for only $18,000. The PDP-8 is referred to as the first realminicomputer because of its sub-$25,000 price.[39][40] Sales were, unsurprisingly, very strong, and helped by the fact that several competitors had just entered the market with machines aimed directly at the PDP-5's market space, which the PDP-8 trounced. This gave the company two years of unrestricted leadership,[41] and eventually 1450 "straight eight" machines were produced before it was replaced by newer implementations of the same basic design.[38]
DEC hit an even lower price-point with the PDP-8/S, the S for "serial". As the name implies the /S used a serial arithmetic unit, which was much slower but reduced costs so much that the system sold for under $10,000.[42] DEC then used the new PDP-8 design as the basis for a new LINC, the two-processor LINC-8. The LINC-8 used one PDP-8 CPU and a separate LINC CPU, and included instructions to switch from one to the other. This allowed customers to run their existing LINC programs, or "upgrade" to the PDP-8, all in software. Although not a huge seller, 142 LINC-8s were sold starting at $38,500.[38] Like the original LINC to PDP-5 evolution, the LINC-8 was then modified into the single-processor PDP-12, adding another 1000 machines to the 12-bit family.[38][43] Newer circuitry designs led to the PDP-8/I and PDP-8/L in 1968.[20] In 1975, one year after an agreement between DEC and Intersil, the Intersil 6100 chip was launched, effectively a PDP-8 on a chip. This was a way to allow PDP-8 software to be run even after the official end-of-life announcement for the DEC PDP-8 product line.
A "B" (blue) series Flip Chip module containing nine transistors, 1971
While the PDP-5 introduced a lower-cost line, 1963's PDP-6 was intended to take DEC into the mainframe market with a 36-bit machine. However, the PDP-6 proved to be a "hard sell" with customers, as it offered few obvious advantages over similar machines from the better-established vendors like IBM or Honeywell, in spite of its low cost around $300,000. Only 23 were sold,[44] or 26 depending on the source,[45] and unlike other models the low sales meant the PDP-6 was not improved with successor versions. However, the PDP-6 is historically important as the platform that introduced "Monitor", an early time-sharingoperating system that would evolve into the widely used TOPS-10.[46]
When newer Flip Chip packaging allowed the PDP-6 to be re-implemented at a much lower cost, DEC took the opportunity to refine their 36-bit design, introducing the PDP-10 in 1968. The PDP-10 was as much a success as the PDP-6 was a commercial failure; about 700 mainframe PDP-10s were sold before production ended in 1984.[44] The PDP-10 was widely used in university settings, and thus was the basis of many advances in computing and operating system design during the 1970s. DEC later re-branded all of the models in the 36-bit series as the "DECsystem-10", and PDP-10s are generally referred to by the model of their CPU, starting with the "KA10", soon upgraded to the "KI10" (I:Integrated circuit); then to "KL10" (L:Large-scale integration ECL logic); also the "KS10" (S: Small form factor). Unified product line upgrades produced the compatible DECSYSTEM-20, along with a TOPS-20 operating system that included virtual memory support.
The Jupiter Project was supposed to continue the mainframe product line into the future by using "gate arrays" with an innovative Air Mover Cooling System, coupled with a built-in floating point processing engine called "FBOX". The design was intended for a top tier scientific computing niche, yet the critical performance measurement was based upon COBOL compilation which did not fully utilize the primary design features of Jupiter technology.[citation needed] When the Jupiter Project was cancelled in 1983, some of the engineers adapted aspects of the 36-bit design into a forthcoming 32-bit design, releasing the high-end VAX8600 in 1985.
One of the most unusual peripherals produced for the PDP-10 was the DECtape. The DECtape was a length of special 3/4-inch wide magnetic tape wound on 5-inch reels. The recording format was a highly reliable redundant 10-track design using fixed-length numbered data "blocks" organized into a standard file structure, including a directory. Files could be written, read, changed, and deleted on a DECtape as though it were a disk drive. For greater efficiency, the DECtape drive could read and write to a DECtape in both directions.
In fact, some PDP-10 systems had no disks at all, using DECtapes alone for their primary data storage. The DECtape was also widely used on other PDP models, since it was much easier to use than hand-loading multiple paper tapes. Primitive early time-sharing systems could use DECtapes as system devices and swapping devices. Although superior to paper tape, DECtapes were relatively slow, and were supplanted once reliable disk drives became affordable.
Magnetic disk storage
DEC disk platters
DEC was both a manufacturer and a buyer of magnetic disk storage, offering more than 100 different models of hard disk drive (HDD) and floppy disk drive (FDD) during its existence.[47] In the 1970s, it was the single largest OEM purchaser of HDDs, procuring from Diablo, Control Data Corporation, Information Storage Systems, and Memorex, among others.
DEC's first internally developed HDD was the RS08, a 256 kWord fixed-head contact-start-stop drive using plated media; it shipped in 1969.
Beginning in the 1970s, DEC moved first its HDD manufacturing and then its mass storage development labs to Colorado Springs.[48]
DEC pioneered a number of HDD technologies, including sampled data servos (RL01, 1977) and serial HDD interfaces (Standard Disk Interconnect, 1983). The last internally developed disk drive family (RA9x series) used plated media, departing from the HDD industry trend to carbon overcoated sputtered media. DEC designated a $400 million investment to bring this product line into production.[48] The RA92 (1.5 GB) was introduced in 1992, using a 14-inch platter.
DEC purchased its FDDs from OEMs such as Shugart Associates, Toshiba, and Sony.
PDP-11/20, the first model of PDP-11 on display at EPFL
DEC's successful entry into the computer market took place during a fundamental shift in the underlying organization of the machines from word lengths based on 6-bit characters to those based on 8-bit words needed to support ASCII.[lower-alpha 1] DEC began studies of such a machine, the PDP-X, but Ken Olsen did not support it as he could not see how it offered anything their existing 12-bit ot 18-bit machines didn't.[49] This led the leaders of the PDP-X project to leave DEC and start Data General, whose 16-bit Data General Nova was released in 1969 and was a huge success.[50]
The success of the Nova finally prompted DEC to take the switch seriously, and they began a crash program to introduce a 16-bit machine of their own. The new system was designed primarily by Harold McFarland, Gordon Bell, Roger Cady, and others.[51] The project was able to leap forward in design with the arrival of Harold McFarland, who had been researching 16-bit designs at Carnegie Mellon University. One of his simpler designs became the basis for the new design, although when they first viewed the proposal, management was not impressed and almost cancelled it.[51]
The result was the PDP-11, released in 1970. It differed from earlier designs considerably. In particular, the new design did not include many of the addressing modes that were intended to make programs smaller in memory, a technique that was widely used on other DEC machines and CISC designs in general. This would mean the machine would spend more time accessing memory, which would slow it down. However, the machine also extended the idea of multiple "General Purpose Registers" (GPRs), which gave the programmer flexibility to use these high-speed memory caches as they needed, potentially addressing the performance issues.
A major advance in the PDP-11 design was DEC's Unibus, which supported all peripherals through memory mapping. This allowed a new device to be added easily, generally only requiring plugging a hardware interface board into the backplane and possibly adding a jumper to the wire wrapped backplane, and then installing software that read and wrote to the mapped memory to control it. The relative ease of interfacing spawned a huge market of third party add-ons for the PDP-11, which made the machine even more useful.
The combination of architectural innovations proved superior to competitors and the "11" architecture was soon the industry leader, propelling DEC back to a strong market position. The design was later expanded to allow paged physical memory and memory protection features, useful for multitasking and time-sharing. Some models supported separate instruction and data spaces for an effective virtual address size of 128 kB within a physical address size of up to 4 MB. Smaller PDP-11s, implemented as single-chip CPUs, continued to be produced until 1996, by which time over 600,000 had been sold.[36]
The RT-11 interactive help screen displayed on a VT-100 display terminal
The PDP-11 supported several operating systems, including Bell Labs' new Unix operating system as well as DEC's DOS-11, RSX-11, IAS, RT-11, DSM-11, and RSTS/E. Many early PDP-11 applications were developed using standalone paper-tape utilities. DOS-11 was the PDP-11's first disk operating system, but was soon supplanted by more capable systems. RSX provided a general-purpose multitasking environment and supported a wide variety of programming languages. IAS was a time-sharing version of RSX-11D. Both RSTS and Unix were time-sharing systems available to educational institutions at little or no cost, and these PDP-11 systems were destined to be the "sandbox" for a rising generation of engineers and computer scientists. Large numbers of PDP-11/70s were deployed in telecommunications and industrial control applications. AT&T Corporation became DEC's largest customer.
RT-11 provided a practical real-time operating system in minimal memory, allowing the PDP-11 to continue DEC's critical role as a computer supplier for embedded systems. Historically, RT-11 also served as the inspiration for many microcomputer OS's, as these were generally being written by programmers who cut their teeth on one of the many PDP-11 models. For example, CP/M used a command syntax similar to RT-11's, and even retained the awkward PIP program used to copy data from one computer device to another. As another historical footnote, DEC's use of "/" for "switches" (command-line options) would lead to the adoption of "\" for pathnames in MS-DOS and Microsoft Windows as opposed to "/" in Unix.[52]
The evolution of the PDP-11 followed earlier systems, eventually including a single-user deskside personal computer form, the MicroPDP-11. In total, around 600,000 PDP-11s of all models were sold. and a wide variety of third-party peripheral vendors had also entered the computer product ecosystem. It was even sold in kit form as the Heathkit H11, although it proved too expensive for Heathikit's traditional hobbyist market.
The introduction of semiconductor memory in the early 1970s, and especially dynamic RAM shortly thereafter, led to dramatic reductions in the price of memory as the effects of Moore's Law were felt. Within years, it was common to equip a machine with all the memory it could address, typically 64kB on 16-bit machines. This led vendors to introduce new designs with the ability to address more memory, often by extending the address format to 18 or 24-bits in machines were otherwise similar to their earlier 16-bit designs.[lower-alpha 2]
In contrast, DEC decided to make a more radical departure. In 1976, they began the design of a machine whose entire architecture was expanded from the 16-bit PDP-11 to a new 32-bit basis. This would allow the addressing of very large memories, which were to be controlled by a new virtual memory system, and would also improve performance by processing twice as much data at a time. The system would, however, maintain compatibility with the PDP-11, by operating in a second mode that sent its 16-bit words into the 32-bit internals, while mapping the PDP-11's 16-bit memory space into the larger virtual 32-bit space.[53]
The result was the VAX architecture, where VAX stands for Virtual Address eXtension (from 16 to 32 bits). The first computer to use a VAX CPU was the VAX-11/780, announced in October 1977, which DEC referred to as a superminicomputer. Although it was not the first 32-bit minicomputer, the VAX-11/780's combination of features, price, and marketing almost immediately propelled it to a leadership position in the market after it was released in 1978. VAX systems were so successful that in 1983, DEC canceled its Jupiter project, which had been intended to build a successor to the PDP-10 mainframe, and instead focused on promoting the VAX as the single computer architecture for the company.[53]
Supporting the VAX's success was the VT52, one of the most successful smart terminals. Building on earlier less successful models, the VT05 and VT50, the VT52 was the first terminal that did everything one might want in a single inexpensive chassis. The VT52 was followed by the even more successful VT100 and its follow-ons, making DEC one of the largest terminal vendors in the industry. This was supported by a line of inexpensive computer printers, the DECwriter line. With the VT and DECwriter series, DEC could now offer a complete top-to-bottom system from computer to all peripherals, which formerly required collecting the required devices from different suppliers.
The VAX processor architecture and family of systems evolved and expanded through several generations during the 1980s, culminating in the NVAXmicroprocessor implementation and VAX 7000/10000 series in the early 1990s.[54]
Early microcomputers
When a DEC research group demonstrated two prototype microcomputers in 1974—before the debut of the MITS Altair—Olsen chose to not proceed with the project. The company similarly rejected another personal computer proposal in 1977.[55] At the time these systems were of limited utility, and Olsen famously derided them in 1977, stating "There is no reason for any individual to have a computer in his home."[56] Unsurprisingly, DEC did not put much effort into the microcomputer area in the early days of the market. In 1977, the Heathkit H11 was announced; a PDP-11 in kit form. At the beginning of the 1980s, DEC built the VT180 (codenamed "Robin"), which was a VT100 terminal with an added Z80-based microcomputer running CP/M, but this product was initially available only to DEC employees.[57]
It was only after IBM had successfully launched the IBM PC in 1981 that DEC responded with their own systems. In 1982, DEC introduced not one, but three incompatible machines which were each tied to different proprietary architectures. The first, the DEC Professional, was based on the PDP-11/23 (and later, the 11/73) running the RSX-11M+ derived, but menu-driven, P/OS ("Professional Operating System"). This DEC machine easily outperformed the PC, but was more expensive than, and completely incompatible with IBM PC hardware and software, offering far fewer options for customizing a system.
Unlike CP/M and DOS microcomputers, every copy of every program for the Professional had to be provided with a unique key for the particular machine and CPU for which it was bought. At that time this was mainstream policy, because most computer software was either bought from the company that built the computer or custom-constructed for one client. However, the emerging third-party software industry disregarded the PDP-11/Professional line and concentrated on other microcomputers where distribution was easier. At DEC itself, creating better programs for the Professional was not a priority, perhaps from fear of cannibalizing the PDP-11 line. As a result, the Professional was a superior machine, running inferior software.[58] In addition, a new user would have to learn an awkward, slow, and inflexible menu-based user interface which appeared to be radically different from PC DOS or CP/M, which were more commonly used on the 8080- and 8088-based microcomputers of the time. A second offering, the DECmate II was the latest version of the PDP-8-based word processors, but not really suited to general computing, nor competitive with Wang Laboratories' popular word processing equipment.
The most popular early DEC microcomputer was the dual-processor (Z80 and 8088) Rainbow 100,[55] which ran the 8-bit CP/M operating system on the Z80 and the 16-bit CP/M-86 operating system on the Intel 8088 processor. It could also run a UNIX System III implementation called VENIX. Applications from standard CP/M could be re-compiled for the Rainbow, but by this time users were expecting custom-built (pre-compiled binary) applications such as Lotus 1-2-3, which was eventually ported along with MS-DOS 2.0 and introduced in late 1983. Although the Rainbow generated some press, it was unsuccessful due to its high price and lack of marketing and sales support.[59] By late 1983 IBM was outselling DEC's personal computers by more than ten to one.[55]
RX50
The way the 400 KB[60] DEC standard[61] RX50[62]floppy disk drive supported DEC's initial offerings seemed to encapsulate their approach to the personal computer market. Although the mechanical drive hardware was nearly identical to other 51⁄4" floppy disk drives available on competing systems,[63] DEC sought to differentiate their product by using a proprietary disk format for the data written on the disk. The DEC format had a higher capacity for data, but the RX50 drives were incompatible with other PC floppy drives. This required DEC owners to buy higher-priced, specially formatted floppy media, which was harder to obtain through standard distribution channels. DEC attempted to enforce exclusive control over its floppy media sales by copyrighting its proprietary disk format, and requiring a negotiated license agreement and royalty payments from anybody selling compatible media. The proprietary data format meant that RX50 floppies were not interchangeable with other PC floppies, further isolating DEC products from the developing de facto standard PC market. Hardware hackers and DEC enthusiasts eventually reverse-engineered the RX50 format,[62][64] but the damage had already been done, in terms of market confusion and isolation.
VAXmate
A further system was introduced in 1986 as the VAXmate, which included Microsoft Windows 1.0 and used VAX/VMS-based file and print servers along with integration into DEC's own DECnet-family, providing LAN/WAN connection from PC to mainframe or supermini. The VAXmate replaced the Rainbow, and in its standard form was the first widely marketed diskless workstation.
Networking and clusters
In 1984, DEC launched its first 10 Mbit/s Ethernet. Ethernet allowed scalable networking, and VAXcluster allowed scalable computing. Combined with DECnet and Ethernet-based terminal servers (LAT), DEC had produced a networked storage architecture which allowed them to compete directly with IBM. Ethernet replaced Token Ring, and went on to become the dominant networking model in use today.
Along with the hardware and protocols, DEC also introduced the VAXcluster concept, which allowed several VAX machines to be tied together into a single larger storage system. VAXclusters allowed a DEC-based company to scale their services by adding new machines to the cluster at any time, as opposed to buying a faster machine and using that to replace a slower one. The flexibility this offered was compelling, and allowed DEC to attack high-end markets formerly out of their reach.
The PDP-11 and VAX lines continued to sell in record numbers. Better yet, DEC was competing very well against the market leader, IBM, taking an estimated $2billion away from them in the mid-80s. In 1986, DEC's profits rose 38% when the rest of the computer industry experienced a downturn, and by 1987 the company was threatening IBM's number one position in the computer industry.[13] Not long thereafter came IBM's VAX Killer offerings, at a time when DEC had twice the sales of IBM in the mid-range computer market.
At its peak, DEC was the second-largest computer company in the world, with over 100,000 employees. It was during this time that the company branched out development into a wide variety of projects that were far from its core business in computer equipment. The company invested heavily in custom software. In the 1970s and earlier most software was custom-written to serve a specific task, but by the 1980s the introduction of relational databases and similar systems allowed powerful software to be built in a modular fashion, potentially saving enormous amounts of development time. Software companies like Oracle became the new darlings of the industry, and DEC started their own efforts in every "hot" niche, in some cases several projects for the same niche. Some of these products competed with DEC's own partners, notably Rdb which competed with Oracle's products on the VAX, part of a major partnership only a few years earlier.
Although many of these products were well designed, most of them were DEC-only or DEC-centric, and customers frequently ignored them and used third-party products instead. This problem was further exacerbated by Olsen's aversion to traditional advertising and his belief that well-engineered products would sell themselves. Hundreds of millions of dollars were spent on these projects, at the same time that workstations using RISC microprocessors were starting to approach VAX CPUs in performance.
Faltering in the market
As microprocessors continued to improve in the 1980s, it soon became clear that the next generation would offer performance and features equal to the best of DECs low-end minicomputer lineup. Worse, the Berkeley RISC and Stanford MIPS designs were aiming to introduce 32-bit designs that would outperform the fastest members of the VAX family, DEC's cash cow.[66]
Constrained by the huge success of their VAX and VMS products, which followed the proprietary model, the company was very late to respond to these threats. In the early 1990s, DEC found its sales faltering and its first layoffs followed. The company that created the minicomputer, a dominant networking technology, and arguably the first computers for personal use, had abandoned the "low end" market, whose dominance with the PDP-8 had built the company in a previous generation. Decisions about what to do about this threat led to infighting within the company that seriously delayed their responses.
One group suggested that every possible development in the industry be poured into the construction of a new VAX family that would leapfrog the performance of the existing machines. This would limit the market erosion in the top-end segment, where profit margins were maximized and DEC could continue to survive as a minicomputer vendor. This line of thought led, eventually, to the VAX 9000 series, which were plagued with problems when they were first introduced in October 1989, already two years late.[67] The problems took so long to work out, and the prices of the systems were so high, that DEC was never able to make the line the success they hoped.
Others within the company felt that the proper response was to introduce their own RISC designs and use those to build new machines. However, there was little official support for these efforts, and no less than four separate small projects ran in parallel at various labs around the US. Eventually these were gathered into the PRISM project, which delivered a credible 32-bit design with some unique features allowing it to serve as the basis of a new VAX implementation.[68] Infighting with teams dedicated to DEC's big iron made funding difficult, and the design was not finalized until April 1988, and then cancelled shortly thereafter.[69] The PRISM project was accompanied by the MICA project, which intended to consolidate VMS and ULTRIX into a single operating system.[70]
Another group concluded that new workstations like those from Sun Microsystems and Silicon Graphics would take away a large part of DEC's existing customer base before the new VAX systems could address the issues, and that the company needed its own Unix workstation as soon as possible. Fed up with slow progress on both the RISC and VAX fronts, a group in Palo Alto started a skunkworks project to introduce their own systems. Selecting the MIPS processor, which was widely available, introducing the new DECstation series with the model 3100 on 11 January 1989.[71] These systems would see some success in the market, but were later displaced by similar models running the Alpha.
32-bit MIPS and 64-bit Alpha systems
Inside view of AlphaServer 2100
Eventually, in 1992, DEC launched the DECchip 21064 processor, the first implementation of their Alphainstruction set architecture, initially named AlphaAXP; the "AXP" was a "non-acronym" and was later dropped. This was a 64-bitRISC architecture as opposed to the 32-bit CISC architecture used in the VAX. It is one of the first "pure" 64-bit microprocessor architectures and implementations rather than an extension of an earlier 32-bit architecture. The Alpha offered class-leading performance at its launch, and subsequent variants continued to do so into the 2000s, along with the Alpha-derived Pentium Pro, II, and III CPUs.[72][73] An AlphaServer SC45 supercomputer was still ranked No.6 in the world in November 2004.[74] Alpha-based computers comprising the DEC AXP series, later the AlphaStation, and AlphaServer series respectively superseded both the VAX and MIPS architecture in DEC's product lines. They supported OpenVMS, DEC OSF/1 AXP (later known as Digital Unix or Tru64 UNIX) and Microsoft's then-new operating system, Windows NT, an operating system made possible by ex-Digital Equipment Corporation engineers.[75]
In 1998, following the takeover by Compaq Computers, a decision was made that Microsoft would no longer support and develop Windows NT for the Alpha series computers, a decision that was seen as the beginning of the end for the Alpha series computers.
In the mid-1990s, Digital Semiconductor collaborated with ARM Limited to produce the StrongARM microprocessor. This was based in part on ARM7 and in part on DEC technologies like Alpha, and was targeted at embedded systems and portable devices. It was highly compatible with the ARMv4 architecture and was very successful, competing effectively against rivals such as the SuperH and MIPS architectures in the portable digital assistant market. Microsoft subsequently dropped support for these other architectures in their Pocket PC platform. In 1997, as part of a lawsuit settlement, the StrongARM intellectual property was sold to Intel. They continued to produce StrongARM, as well as developing it into the XScale architecture. Intel subsequently sold this business to Marvell Technology Group in 2006.
Video and Interactive Information Server
The Video-on-Demand project at DEC started in 1992, following Ken Olsen's retirement. At the time the company was rapidly downsizing under Robert Palmer, and it was difficult to gain funding for any new project. DEC's Interactive Video Information Server architecture gained traction and excelled over those of other companies, in that it was highly scalable, using a gateway to set up interactive video delivery sessions on large numbers of video and information servers. Initially high-end VAXes were used, then Alphas.[76][77]
The scalability feature allowed it to win contracts for many of the video-on-demand trials in the 1993–95 timeframe, since the system could theoretically accommodate unlimited interactive video streams and other non-video content.[78]
The design was proposed and incorporated into the MPEG2 international standard.[79] Its object-oriented interface became the mandatory user-to user core interface in DSM-CC, widely used in video stream and file delivery for MPEG-2 compliant systems.
Commercially, DEC's Digital and Interactive Information System was used by Adlink to distribute advertising to over 2 million subscribers.[80][81]
Final years
Redesigned logo introduced in 1993
At its peak in the late 1980s, DEC had $14 billion in sales and ranked among the most profitable companies in the US. With its strong staff of engineers, DEC was expected to usher in the age of personal computers, but the autocratic and trend-resistant Mr. Olsen was openly skeptical of the desktop machines, saying "the personal computer will fall flat on its face in business", and regarding them as "toys" used for playing video games. DEC's fortunes declined after missing out on some critical market shifts, particularly toward the personal computer. The board forced Olsen to resign as president in July 1992.[82]
Palmer
In June 1992, Ken Olsen was replaced by Robert Palmer as the company's president. DEC's board of directors also granted Palmer the title of chief executive officer ("CEO"), a title that had never been used during DEC's 35-year existence. Palmer had joined DEC in 1985 to run Semiconductor Engineering and Manufacturing. His relentless campaign to be CEO, and success with the Alpha microprocessor family, made him a candidate to succeed Olsen. At the same time a more modern logo was designed[83]
Palmer restructured DEC into nine business units that reported directly to him. Nonetheless, DEC continued to suffer record losses, including a loss of $260.5 million for the quarter that ended on 30 September 1992. It reported $2.8 billion in losses for its fiscal year 1992. 5 January 1993 saw the retirement of John F. Smith as senior vice president of operations, the second in command at DEC, and his position was not filled. A 35-year company veteran, he had joined DEC in 1958 as the company's 12th employee, passing up a chance to work for Bell Laboratories in New Jersey to work for DEC. Smith rose to become one of the three senior vice presidents in 1987 and was widely considered among the potential successors to Ken Olsen, especially when Smith was appointed chief operating officer in 1991. Smith became a corporate spokesman on financial issues, and had filled in at trouble spots for which Olsen ordered more attention. Smith was passed over in favor of Palmer when Olsen was forced to resign in July 1992, though Smith stayed on for a time to help turn around the struggling company.[84]
In June 1993, Palmer and several of his top lieutenants presented their reorganization plans to applause from the board of directors, and several weeks later DEC reported its first profitable quarter in several years. However, on 15 April 1994, DEC reported a loss of $183 million—three to four times higher than the loss many people on Wall Street had predicted (compared with a loss of $30 million in the comparable period a year earlier), causing the stock price on the NYSE to plunge $5.875 to $23, a 20% drop. The losses at that point totaled $339 million for the current fiscal year. Sales of the VAX, long the company's biggest moneymaker, continued to decline, which in turn also hurt DEC's lucrative service and maintenance business (this made up more than a third of DEC's revenue of $14 billion in the 1993 fiscal year), which declined 11% year over year to $1.5 billion in the most recent quarter.
Market acceptance of DEC Alpha computers and chips had been slower than the company had hoped, even though Alpha's sales for the quarter estimated at $275 million were up significantly from $165 million in the December quarter. DEC had also made a strong push into personal computers and workstations, which had even lower margins than Alpha computers and chips. Also, DEC was playing catchup with its own Unix offerings for client-server networks, as it long emphasized its own VMS software, while corporate computer users based their client-server networks on the industry-standard Unix software (of which Hewlett Packard was one of the market leaders). DEC's problems were similar to that of larger rival IBM, due to the fundamental shift in the computer industry that made it unlikely that DEC could ever again operate profitably at its former size of 120,000 employees, and while its workforce had been reduced to 92,000 people many analysts expected that they would have to cut another 20,000.[85]
Selloffs
DECpc 425SE Color: a notebook computer released by Digital in 1993
During the profitable years up until the early 1990s, DEC was a company that boasted that it never had a general layoff.[86] Following the 1992 economic downturn, layoffs became regular events as the company continually downsized to try to stay afloat.[87] Palmer was tasked with the goal of bringing DEC back to profitability, which he attempted to do by changing the established DEC business culture, hiring new executives from outside the company, and selling off various non-core business units:[88]
Worldwide training was spun off to form an independent/new company called Global Knowledge Network.
Rights to the PDP-11 line and several PDP-11 operating systems were sold to Mentec in 1994, though DEC continued to produce some PDP-11 hardware for a few years.[89]
Through 1997, DEC began discussions with Compaq on a possible merger. Several years earlier, Compaq had considered a bid for DEC but became seriously interested only after DEC's major divestments and refocusing on the Internet in 1997. At that time, Compaq was making strong moves into the enterprise market, and DEC's multivendor global services organization and customer support centers offered a real opportunity to expand their support and sales worldwide. Compaq was not interested in a number of DEC's product lines, which led to the series of sell-offs. Notable among these was DEC's Hudson Fab, which made most of their custom chips, a market that made little sense to Compaq's "industry standard" marketing. DEC had previously sold its semiconductor plant in South Queensferry to Motorola in 1995, with an undertaking that Motorola would continue to produce Alpha processors at the facility, along with continuing a two-year foundry agreement with AMD to continue producing the Am486 processor.[90]
This led to an interesting solution to the problem of selling off the division for a reasonable profit. In May 1997, DEC sued Intel for allegedly infringing on its Alpha patents in designing the original Pentium, Pentium Pro, and Pentium II chips.[91] As part of a settlement, much of DEC's chip design and fabrication business was sold to Intel. This included DEC's StrongARM implementation of the ARM computer architecture, which Intel marketed as the XScale processors commonly used in Pocket PCs. The core of Digital Semiconductor, the Alpha microprocessor group, remained with DEC, while the associated office buildings went to Intel as part of the Hudson fab.[92]
On 26 January 1998, what remained of the company was sold to Compaq in what was the largest merger up to that time in the computer industry. At the time of Compaq's acquisition announcement, DEC had a total of 53,500 employees, down from a peak of 130,000 in the 1980s, but it still employed about 65% more people than Compaq to produce about half the volume of sales revenues. After the merger closed, Compaq moved aggressively to reduce DEC's high selling, general, and administrative (SG&A) costs (equal to 24% of total 1997 revenues) and bring them more in line with Compaq's SG&A expense ratio of 12% of revenues.[93]
Compaq used the acquisition to move into enterprise services and compete with IBM, and by 2001 services made up over 20% of Compaq's revenues, largely due to the DEC employees inherited from the merger.[94] DEC's own PC manufacturing was discontinued after the merger closed. As Compaq did not wish to compete with one of its key partner suppliers, the remainder of Digital Semiconductor (the Alpha microprocessor group) was sold to Intel, which placed those employees back in their Hudson (Massachusetts) office, which they had vacated when the site was sold to Intel in 1997.
Compaq struggled as a result of the merger with DEC,[93] and was acquired by Hewlett-Packard in 2002. Compaq, and later HP, continued to sell many of the former DEC products but re-branded with their own logos. For example, HP now sells what were formerly DEC's StorageWorks disk/tape products,[95] as a result of the Compaq acquisition.
The Digital logo was used up until 2004, even after the company ceased to exist, as the logo of Digital GlobalSoft, an IT services company in India (which was a 51% subsidiary of Compaq). Digital GlobalSoft was later renamed "HP GlobalSoft" (also known as the "HP Global Delivery India Center" or HP GDIC), and no longer uses the Digital logo.
Footnotes
↑ Although ASCII is a 7-bit standard, units-of-8-bits are typically used for machines that support it.
↑ An example is the DG Nova 840, which used a 17-bit format, up from the previous 15-bits.
↑ "Ken Olsen, Founder of DEC, Dies at 84". The New York Times. February 8, 2011. Ken Olsen ... M.I.T.'s new Lincoln Laboratory .. recruited ..colleague, Harlan Anderson, ...
1 2 3 4 5 "Digital Equipment Corporation", International Directory of Company Histories, Volume 6, St. James Press, 1992 [Note this link is to answers.com, not the International Directory of Company Histories]
↑ Richard Best, Russell Doane and John McNamara, "Digital Modules, The Basis for Computers", in Computer Engineering, A DEC view of hardware systems design, Digital Press, 1978
↑ Katan, M.B., Scholte, B.A., 1984. Application of a Professional 350 in a university department— a consumer's report, in: Proceedings Digital Equipment Computer Users Society. Amsterdam, p. 368.
↑ Wilson, John. "PUTR.COM V2.01". Retrieved 21 March 2011. This relatively recent work is a well-developed example of programs to enhance interchange of data between DEC formatted media and standard PC systems
↑ Daniel Minoli, Video Dialtone Technology: Digital Video over ADSL, HFC, FTTC, and ATM, Mcgraw Hill, Inc., 1995.
↑ ISO/IEC 13818-1, part 6, DSM-CC TC1/SC29/WG11, Digital Storage Media Command & Control, November 1994.
↑ The Free Library, Adlink selects Digital to implement new video ad insertion system, 11 January 1995.
↑ Borko Furht, Multimedia Technologies and Applications for the 21st Century: Visions of World Experts, Springer Science & Business Media, 30 Nov 1997.
Digital Equipment Corporation, using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until forced to resign in 1992, after the company had gone into precipitous decline.
Alpha is a 64-bit reduced instruction set computer (RISC) instruction set architecture (ISA) developed by Digital Equipment Corporation (DEC). Alpha was designed to replace 32-bit VAX complex instruction set computers (CISC) and to be a highly competitive RISC processor for Unix workstations and similar markets.
A minicomputer, or colloquially mini, is a class of smaller general purpose computers that developed in the mid-1960s and sold for much less than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, The New York Times suggested a consensus definition of a minicomputer as a machine costing less than US$25,000, with an input-output device such as a teleprinter and at least four thousand words of memory, that is capable of running programs in a higher level language, such as Fortran or BASIC.
Digital Equipment Corporation (DEC)'s PDP-10, later marketed as the DECsystem-10, is a mainframe computer family manufactured beginning in 1966 and discontinued in 1983. 1970s models and beyond were marketed under the DECsystem-10 name, especially as the TOPS-10 operating system became widely used.
Programmed Data Processor (PDP), referred to by some customers, media and authors as "Programmable Data Processor," is a term used by the Digital Equipment Corporation from 1957 to 1990 for several lines of minicomputers.
The PDP-11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC's most successful product lines. The PDP-11 is considered by some experts to be the most popular minicomputer.
VAX is a series of computers featuring a 32-bit instruction set architecture (ISA) and virtual memory that was developed and sold by Digital Equipment Corporation (DEC) in the late 20th century. The VAX-11/780, introduced October 25, 1977, was the first of a range of popular and influential computers implementing the VAX ISA. The VAX family was a huge success for DEC - over 100 models were introduced over the lifetime of the design, with the last members arriving in the early 1990s. The VAX was succeeded by the DEC Alpha, which included several features from VAX machines to make porting from the VAX easier.
OpenVMS, often referred to as just VMS, is a multi-user, multiprocessing and virtual memory-based operating system. It is designed to support time-sharing, batch processing, transaction processing and workstation applications. Customers using OpenVMS include banks and financial services, hospitals and healthcare, telecommunications operators, network information services, and industrial manufacturers. During the 1990s and 2000s, there were approximately half a million VMS systems in operation worldwide.
Computer operating systems (OSes) provide a set of functions needed and used by most application programs on a computer, and the links needed to control and synchronize computer hardware. On the first computers, with no operating system, every program needed the full hardware specification to run correctly and perform standard tasks, and its own drivers for peripheral devices like printers and punched paper card readers. The growing complexity of hardware and application programs eventually made operating systems a necessity for everyday use.
Data General was one of the first minicomputer firms of the late 1960s. Three of the four founders were former employees of Digital Equipment Corporation (DEC).
Ultrix is the brand name of Digital Equipment Corporation's (DEC) discontinued native Unix operating systems for the PDP-11, VAX, MicroVAX and DECstations.
The PDP-6, short for Programmed Data Processor model 6, is a computer developed by Digital Equipment Corporation (DEC) during 1963 and first delivered in the summer of 1964. It was an expansion of DEC's existing 18-bit systems to use a 36-bit data word, which was at that time a common word size for large machines like IBM mainframes. The system was constructed using the same germanium transistor-based System Module layout as DEC's earlier machines, like the PDP-1 and PDP-4.
OS/8 was the primary operating system used on the Digital Equipment Corporation's PDP-8 minicomputer.
PRISM was a 32-bit RISC instruction set architecture (ISA) developed by Digital Equipment Corporation (DEC). It was the outcome of a number of DEC research projects from the 1982–1985 time-frame, and the project was subject to continually changing requirements and planned uses that delayed its introduction. This process eventually decided to use the design for a new line of Unix workstations. The arithmetic logic unit (ALU) of the microPrism version had completed design in April 1988 and samples were fabricated, but the design of other components like the floating point unit (FPU) and memory management unit (MMU) were still not complete in the summer when DEC management decided to cancel the project in favor of MIPS-based systems. An operating system codenamed MICA was developed for the PRISM architecture, which would have served as a replacement for both VAX/VMS and ULTRIX on PRISM.
DECtape, originally called Microtape, is a magnetic tape data storage medium used with many Digital Equipment Corporation computers, including the PDP-6, PDP-8, LINC-8, PDP-9, PDP-10, PDP-11, PDP-12, and the PDP-15. On DEC's 32-bit systems, VAX/VMS support for it was implemented but did not become an official part of the product lineup.
The Advanced Computing Environment (ACE) was defined by an industry consortium in the early 1990s to be the next generation commodity computing platform, the successor to personal computers based on Intel's 32-bit instruction set architecture. The effort found little support in the market and dissolved due to infighting within the group and a lack of sales.
The PDP-15 was the fifth and last of the 18-bit minicomputers produced by Digital Equipment Corporation. The PDP-1 was first delivered in December 1959 and the first PDP-15 was delivered in February 1970. More than 400 of these successors to the PDP-9 were ordered within the first eight months.
The Professional 325 (PRO-325), Professional 350 (PRO-350), and Professional 380 (PRO-380) were PDP-11 compatible microcomputers introduced in 1982 by Digital Equipment Corporation (DEC) as high-end competitors to the IBM PC.
The Massbus is a high-performance computer input/output bus designed in the 1970s by Digital Equipment Corporation (DEC). The architecture development was sponsored by Gordon Bell and John Levy was the principal architect.
The VAX 9000 is a discontinued family of mainframe computers developed and manufactured by Digital Equipment Corporation (DEC) using custom ECL-based processors implementing the VAX instruction set architecture (ISA). Equipped with optional vector processors, they were marketed into the supercomputer space as well. As with other VAX systems, they were sold with either the VMS or Ultrix operating systems.
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