The VAX-11 is a discontinued family of 32-bit superminicomputers , running the Virtual Address eXtension (VAX) instruction set architecture (ISA), developed and manufactured by Digital Equipment Corporation (DEC). Development began in 1976. In addition to being powerful machines in their own right, they also offer the additional ability to run user mode PDP-11 code (thus the -11 in VAX-11), offering an upward compatible path for existing customers.
102-582: The first machine in the series, the VAX-11/780, was announced in October 1977. Its former competitors in the minicomputer space, like Data General and Hewlett-Packard , were unable to successfully respond to the introduction and rapid update of the VAX design. DEC followed the VAX-11/780 with the lower-cost 11/750, and the even lower cost 11/730 and 11/725 models in 1982. More powerful models, initially known as
204-528: A 19-inch rack . Many PDP-8s still operated decades later in these roles. De Castro was watching developments in manufacturing, especially more complex printed circuit boards (PCBs) and wave soldering that suggested that the PDP-8 could be produced much more inexpensively. DEC was not interested, having turned its attention increasingly to the high-end market. Convinced he could improve the process, De Castro began work on his own low-cost 16-bit design. The result
306-413: A VMScluster . Digital used the performance of the VAX-11/780 as a reference point for describing the performance of subsequent VAX models. The performance of the VAX-11/780 became known as 1 VAX Unit of Performance (or 1.0 VUPs). Other VAX models are rated as a multiple of the VAX-11/780's performance, for example, a 2.0 VUPs VAX is twice as fast as the VAX-11/780. The VAX-11/782 , code-named "Atlas",
408-621: A 15 volt power supply and were found in industrial control, where the high differential was intended to minimize the effect of noise. P-type MOS (PMOS) logic uses p-channel MOSFETs to implement logic gates and other digital circuits . N-type MOS (NMOS) logic uses n-channel MOSFETs to implement logic gates and other digital circuits. For devices of equal current driving capability, n-channel MOSFETs can be made smaller than p-channel MOSFETs, due to p-channel charge carriers ( holes ) having lower mobility than do n-channel charge carriers ( electrons ), and producing only one type of MOSFET on
510-579: A 29-bit physical address space, allowing it to address a theoretical maximum of 512MB of memory. The memory is constructed from 4 or 16 kbit metal oxide semiconductor (MOS) RAM chips mounted on memory array cards. Each memory controller controls up to 16 array cards. The memory is protected by error correcting code (ECC). The VAX-11/780 uses the Unibus and Massbus for I/O. Unibus is used for attaching lower-speed peripherals such as terminals and printers and Massbus for higher-speed disk and tape drives. After
612-454: A 5V power supply. They form a replacement for TTL, although HCT is slower than original TTL (HC logic has about the same speed as original TTL). Other CMOS circuit families within integrated circuits include cascode voltage switch logic (CVSL) and pass transistor logic (PTL) of various sorts. These are generally used "on-chip" and are not delivered as building-block medium-scale or small-scale integrated circuits. One major improvement
714-450: A VAX 11/780. This model is essentially a copy of the "dual VAX-11/780" computers hand built by wire-wrapping the backplanes of two VAX-11/780 CPUs by then graduate student George H. Goble and undergraduate assistants at Purdue University as part of his work on his Master's Degree thesis on modifications of the Unix kernel for multi-cpu architecture. The VAX-11/784 , code-named "VAXimus",
816-471: A capacitance C and changing V volts is ½ CV . By lowering the power supply from 5V to 3.3V, switching power was reduced by almost 60 percent ( power dissipation is proportional to the square of the supply voltage). Many motherboards have a voltage regulator module to provide the even lower power supply voltages required by many CPUs. Because of the incompatibility of the CD4000 series of chips with
918-456: A current-steering arrangement to implement logic functions. It was used in some integrated circuits, but it is now considered obsolete. The following logic families would either have been used to build up systems from functional blocks such as flip-flops, counters, and gates, or else would be used as "glue" logic to interconnect very-large scale integration devices such as memory and processors. Not shown are some early obscure logic families from
1020-533: A decision, it was often cheaper for the users to simply throw out all of their existing machinery and buy a microcomputer product instead. If this was not the case at present, it certainly appeared it would be within a generation or two of Moore's law . In 1988, two company directors put together a report showing that if the company were to continue existing in the future, DG would have to either invest heavily in software to compete with new applications being delivered by IBM and DEC on their machines, or alternately exit
1122-405: A desktop". The early AViiON servers were portrayed as powerful computing in the size of a pizza box. Logic family#Transistor–transistor logic (TTL) In computer engineering , a logic family is one of two related concepts: Before the widespread use of integrated circuits, various solid-state and vacuum-tube logic systems were used but these were never as standardized and interoperable as
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#17327867088381224-466: A few EMC webpages that only mentioned the latter company in passing, was sold to the Dollar General discount department store chain in October 2009. Data General exhibited a brash style of marketing and advertising, which acted to set the company in the spotlight. A memorable advertising campaign during the early 1980s Desktop Generation era, was issuance of T-shirts with the logo "We did it on
1326-402: A front end processor, a PDP-11/03 , which is used to run local and remote diagnostics. The VAX-11/780 originally supported up to 8MB of memory through one or two MS780-C memory controllers, with each controller supporting between 128KB-4MB of memory. The later MS780-E memory controller supports 4MB-64MB of memory, allowing the VAX-11/780 to support up to a total of 128MB of memory. The KA780 has
1428-407: A gate length of 20 μm and a gate oxide thickness of 100 nm . However, the nMOS devices were impractical, and only the pMOS type were practical working devices. A more practical NMOS process was developed several years later. NMOS was initially faster than CMOS , thus NMOS was more widely used for computers in the 1970s. With advances in technology, CMOS logic displaced NMOS logic in
1530-480: A language runtime system implemented as a virtual machine which executed pre-compiled code as sequences of PLN statements and Eclipse commercial instruction routines. The latter provided microcode acceleration of arithmetic and conversion operations for a wide range of now-arcane data types such as overpunch characters. The DG Easy product, a portable application platform developed by Nichols and others from 1975 to 1979 but never marketed, had roots easily traceable back to
1632-480: A large niche for Unix storage systems, and its sales were still strong enough to make DG a takeover target. EMC , the 800-pound gorilla in the storage market, announced in August 1999 that they would buy Data General and its assets for $ 1.1 billion or $ 19.58 a share. The acquisition was completed on October 12, 1999. Although details of the acquisition specified that EMC had to take the entire company, and not just
1734-559: A major product line in the later 1990s. This led to a purchase by EMC , the major vendor in the storage space at that time. EMC shut down all of DG's lines except for CLARiiON, which continued sales until 2012. Data General (DG) was founded by several engineers from Digital Equipment Corporation who were frustrated with DEC's management and left to form their own company. The chief founders were Edson de Castro , Henry Burkhardt III, and Richard Sogge of Digital Equipment (DEC), and Herbert Richman of Fairchild Semiconductor . The company
1836-404: A more powerful machine, it was often cheaper to buy another from the same company. This was known as " vendor lock-in ", which helped guarantee future sales, even though the customers detested it. With the change in software development, combined with new generations of commodity processors that could match the performance of low-end minicomputers, lock-in was no longer working. When forced to make
1938-442: A silicon substrate is cheaper and technically simpler. These were the driving principles in the design of NMOS logic which uses n-channel MOSFETs exclusively. However, neglecting leakage current , unlike CMOS logic, NMOS logic consumes power even when no switching is taking place. The MOSFET invented at Bell Labs between 1955 and 1960, had both pMOS and nMOS devices with a 20 μm process . Their original MOSFET devices had
2040-553: A small range of tasks. For instance, IBM often delivered machines whose only purpose was to generate accounting data for a single company, running software tailored for that company alone. By the mid-1980s, the introduction of new software development methods and the rapid acceptance of the SQL database was changing the way such software was developed. Now developers typically linked together several pieces of existing software, as opposed to developing everything from scratch. In this market,
2142-414: Is a dual-processor VAX-11/780 introduced in 1982. Both processors share the same MA780 multiport memory bus and the system operates asymmetrically, with the primary CPU performing all I/O operations and process scheduling with the second, attached processor only used for additional computationally-intensive work. For multistream computation-intensive tasks the system delivers up to 1.8 times the performance of
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#17327867088382244-588: Is a rare quad-processor variant of the VAX-11/780. Similar to the VAX-11/782, it is an asymmetric multiprocessing system, with all four KA780 processors sharing the same MA780 multiport memory bus. Its performance is rated as 3.5 VUPs. Avie Tevanian , a founder of the Mach project, has claimed in an interview that he used a VAX-11/784 to run early versions of the Mach kernel. The VAX-11/785 , code-named "Superstar",
2346-510: Is the first computer to implement the VAX architecture. The KA780 central processing unit (CPU) is built from Schottky transistor-transistor logic (TTL) devices and has a 200 ns cycle time (5 MHz) and a 2 KB cache. Memory and I/O are accessed via the Synchronous Backplane Interconnect (SBI). The CPU is microprogrammed. The microcode is loaded at boot time from an 8" floppy disk controlled by
2448-577: Is unclear whether any were produced. The VAX-11/750, code-named "Comet", is a more compact, lower-performance bipolar gate array –based implementation of the VAX architecture introduced in October 1980. The use of gate arrays decreases power consumption, and increases reliability compared with the VAX-11/780. The KA750 CPU has a 320 ns cycle time (3.125 MHz), and a VUPs rating of 0.6. The system can support up to 2MB of memory with an L0011 memory controller, up to 8MB with an L0016 memory controller, or up to 14MB with an L0022 memory controller. While
2550-559: Is when at least some of the devices of the family were available in volume for civilian uses. Some military applications pre-dated civilian use. Several techniques and design styles are primarily used in designing large single-chip application-specific integrated circuits (ASIC) and CPUs, rather than generic logic families intended for use in multi-chip applications. These design styles can typically be divided into two main categories, static techniques and clocked dynamic techniques . (See static versus dynamic logic for some discussion on
2652-701: The Schottky effect , which led to the Schottky diode and later Schottky transistors . For the same power dissipation, Schottky transistors have a faster switching speed than conventional transistors because the Schottky diode prevents the transistor from saturating and storing charge; see Baker clamp . Gates built with Schottky transistors use more power than normal TTL and switch faster. With Low-power Schottky (LS), internal resistance values were increased to reduce power consumption and increase switching speed over
2754-609: The Data General Eclipse MV/8000 , whose development was extensively documented in the popular book, The Soul of a New Machine . Although DG's computers were successful, the introduction of the IBM PC in 1981 marked the beginning of the end for minicomputers, and by the end of the decade, the entire market had largely disappeared. The introduction of the Data General/One in 1984 did nothing to stop
2856-431: The Data General/One (DG-1) in 1984 is one of the few cases of a minicomputer company introducing a truly breakthrough PC product. Considered genuinely portable, rather than "luggable", as alternatives often were called, it was a nine-pound battery-powered MS-DOS machine equipped with dual 3 1 ⁄ 2 -inch diskettes, a 79-key full-stroke keyboard, 128 KB to 512 KB of RAM, and a monochrome LCD screen capable of either
2958-511: The Motorola 88000 RISC processor. The AViiON machines supported multi-processing, later evolving into NUMA -based systems, allowing the machines to scale upwards in performance by adding additional processors. An important element in all enterprise computer systems is high speed storage. At the time AViiON came to market, commodity hard disk drives could not offer the sort of performance needed for data center use. DG attacked this problem in
3060-605: The Open Systems Interconnection (OSI) protocol suite . Data General produced a full range of peripherals, sometimes by rebadging printers for example, but Data General's own series of CRT-based and hard-copy terminals were high quality and featured a generous number of function keys, each with the ability to send different codes, with any combination of control and shift keys, which influenced WordPerfect design. The model 6053 Dasher 2 featured an easily tilted screen, but used many integrated circuits ;
3162-617: The Xerox Alto . In 1974, the Nova was supplanted by their upscale 16-bit machine, the Eclipse . Based on many of the same concepts as the Nova, it included support for virtual memory and multitasking more suitable to the small office environment. For this reason, the Eclipse was packaged differently, in a floor-standing case resembling a small refrigerator . Production problems with
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3264-531: The ideal logic device that combined high speed, with low power dissipation and compatibility with older logic families. A whole range of newer families has emerged that use CMOS technology. A short list of the most important family designators of these newer devices includes: There are many others including AC/ACT logic , AHC/AHCT logic , ALVC logic , AUC logic , AVC logic , CBT logic , CBTLV logic , FCT logic and LVC logic ( LVCMOS ). The integrated injection logic (IIL or I L) uses bipolar transistors in
3366-513: The 11/780 boots from a 8” floppy via its console processor, the VAX 11/750 is equipped with a TU58 (DECtape II) cassette drive for first level booting and diagnostics. A ruggedized rack-mount VAX-11/750. Introduced in April 1982, the VAX-11/730, code-named "Nebula", is a still-more-compact, still-lower-performance bit slice implementation of the VAX architecture using AMD Am2900 chips for
3468-443: The 12-bit PDP-8 . A basic Nova system cost two-thirds or less than a similar PDP-8 while running faster, offering easy expandability, being significantly smaller, and proving more reliable in the field. Combined with Data General RDOS (DG/RDOS) and programming languages like Data General Business Basic , Novas provided a multi-user platform far ahead of many contemporary systems. A series of updated Nova machines were released through
3570-536: The CPU. The KA730 CPU has a 270 ns cycle time (3.70 MHz), and a VUPs rating of 0.3. It supports up to 5MB of memory. Code-named "LCN" ("Low-Cost Nebula"), it is a cost-reduced model of the VAX-11/730. It uses the same KA730 CPU as the VAX-11/730, but is housed in a more compact enclosure designed to reduce noise and heat ("55 dB" and "575 W (max.)"), making it more suitable for use in an office environment. It supports up to 3MB of memory. The VAX-11/790 and VAX-11/795 are
3672-471: The DG One Portable. Some software development from the early 1970s is notable. PLN (created by Robert Nichols) was the host language for a number of DG products, making them easier to develop, enhance, and maintain than macro assembler equivalents. PLN smacked of a micro-subset of PL/I , in sharp contrast to other languages of the time, such as BLISS . The RPG product (shipped in 1976) incorporated
3774-517: The DG factory in Mexico where they were made and refurbished. In retrospect, the nicely performing MV series was too little, too late. At a time when DG invested its last dollar into the dying minicomputer segment, the microcomputer was rapidly making inroads to the lower-end market segment, and the introduction of the first workstations wiped out all 16-bit machines, once DG's best customer segment. While
3876-558: The Desktop Generation range also struggled, partly because they offered an economical way of running what was essentially "legacy software" while the future was clearly either slightly cheaper Personal Computers or slightly more expensive "super minicomputers" such as the MV and VAX computers. Throughout the 1980s, the computer market had evolved dramatically. Large installations in the past typically ran custom-developed software for
3978-416: The Eclipse led to a rash of lawsuits in the late 1970s. Newer versions of the machine were pre-ordered by many of DG's customers, which were never delivered. Many customers sued Data General after more than a year of waiting, charging the company with breach of contract , while others simply canceled their orders and went elsewhere. The Eclipse was originally intended to replace the Nova outright, evidenced by
4080-619: The Eclipse MV line, and a modified version of UNIX System V called DG/UX for the Eclipse MV and AViiON machines. The AOS/VS software was the most commonly used DG software product and included CLI (Command Line Interpreter) allowing for complex scripting, DUMP/LOAD, and other custom components. Related system software also in common use at the time included such packages as X.25 , Xodiac, and TCP/IP for networking, Fortran , COBOL , RPG , PL/I , C and Data General Business Basic for programming, INFOS II and DG/DBMS for databases, and
4182-448: The MV series did stop the erosion of DG's customer base, this now smaller base was no longer large enough to allow DG to develop their next generation. DG had also changed their marketing to focus on direct sales to Fortune 100 companies and thus alienated many resellers. Data General developed operating systems for its hardware: DOS and RDOS for the Nova, RDOS and AOS for the 16-bit Eclipse C, M, and S lines, AOS/VS and AOS/VS II for
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4284-581: The MV/2000 (later MV/2500), MV/4000, MV/10000, MV/15000, MV/20000, MV/30000, MV/40000 and ultimately concluded with the MV/60000HA minicomputer. The MV/60000HA was intended to be a High Availability system, with many components duplicated to eliminate the single point of failure. Yet, there were failures among the system's many daughter boards, back-plane, and mid-plane. DG technicians were kept quite busy replacing boards and many blamed poor quality control at
4386-402: The Nova generated 20% annual growth rates for the company, becoming a star in the business community and generating US$ 100 million in sales in 1975. In 1977, DG launched a 16-bit microcomputer called the microNOVA to poor commercial success. The Nova series played a very important role as instruction-set inspiration to Charles P. Thacker and others at Xerox PARC during their construction of
4488-463: The RPG VM created by Stephen Schleimer. Also notable were several commercial software products developed in the mid to late 1970s in conjunction with the commercial computers. These products were popular with business customers because of their screen design feature and other ease-of-use features. The original IDEA ran on RDOS and would support up to 24 users in an RDOS Partition. Each user could use
4590-599: The VAX-11/790 and VAX-11/795, were instead rebranded as the VAX 8600 series. The VAX-11 line was discontinued in 1988, having been supplanted by the MicroVAX family on the low end, and the VAX 8000 family on the high end. The VAX-11/780 is historically one of the most successful and studied computers in history. The VAX-11/780 , code-named "Star", was introduced on 25 October 1977 at DEC's Annual Meeting of Shareholders. It
4692-657: The aging of DEC's 16-bit products, notably the PDP-11 , which were coming due for replacement. It appeared there was an enormous potential market for 32-bit machines, one that DG might be able to "scoop". Data General immediately launched their own 32-bit effort in 1976 to build what they called the "world's best 32-bit machine", known internally as the "Fountainhead Project", or FHP for short (Fountain Head Project). Development took place off-site so that even DG workers would not know of it. The developers were given free rein over
4794-440: The best "commodity" machines instead. "Specifically", the report stated, "DG should examine the Unix market, where all of the needed software already exists, and see if DG can provide compelling Unix solutions." Now the customer could run any software they wished as long as it ran on Unix, and by the early 1990s, everything did. As long as DG's machines outperformed the competition, their customers would return, because they liked
4896-528: The design and selected a system that used a writable instruction set. The idea was that the instruction set architecture (ISA) was not fixed, programs could write their own ISA and upload it as microcode to the processor's writable control store . This would allow the ISA to be tailored to the programs being run, for instance, one might upload an ISA tuned for COBOL if the company's workload included significant numbers of COBOL programs. When Digital's VAX-11/780
4998-596: The early 1960s such as DCTL (direct-coupled transistor logic), which did not become widely available. Propagation delay is the time taken for a two-input NAND gate to produce a result after a change of state at its inputs. Toggle speed represents the fastest speed at which a J-K flip flop could operate. Power per gate is for an individual 2-input NAND gate; usually there would be more than one gate per IC package. Values are very typical and would vary slightly depending on application conditions, manufacturer, temperature, and particular type of logic circuit. Introduction year
5100-448: The early 1970s that kept the Nova line at the front of the 16-bit mini world. The Nova was followed by the Eclipse series which offered much larger memory capacity while still being able to run Nova code without modification. The Eclipse launch was marred by production problems and it was some time before it was a reliable replacement for the tens of thousands of Novas in the market. As the mini world moved from 16-bit to 32, DG introduced
5202-512: The erosion. In a major business pivot, in 1989 DG released the AViiON series of scalable Unix systems which spanned from desktop workstations to departmental servers . This scalability was managed through the use of NUMA , allowing a number of commodity processors to work together in a single system. Following AViiON was the CLARiiON series of network-attached storage systems which became
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#17327867088385304-538: The explosion of the internet in the latter 1990s with the formation of the THiiN Line business unit, led by Tom West, which had a focus on creation and sale of so-called "internet appliances". The product developed was called the SiteStak web server appliance and was designed as an inexpensive website hosting product. CLARiiON was the only product line that saw continued success through the later 1990s after finding
5406-476: The fact that the Nova 3 series, released at the same time and utilizing virtually the same internal architecture as the Eclipse, was phased out the next year. Strong demand continued for the Nova series, resulting in the Nova 4, perhaps as a result of the continuing problems with the Eclipse. While DG was still struggling with Eclipse, in 1977, Digital announced the VAX series, their first 32-bit minicomputer line, described as " super-minis ". This coincided with
5508-493: The first joint venture between an American computer company and a Soviet company. DG would provide hardware and NPO Parma the software, and Austrian companies Voest Alpine Industrieanlagenbau and their marketing group Voest Alpine Vertriebe would build the plant. Despite Data General's betting the AViiON farm on the Motorola 88000 , Motorola decided to end production of that CPU. The 88000 had never been very successful, and DG
5610-495: The full-sized standard 80×25 characters or full CGA graphics (640×200). The DG-1 was considered a modest advance over similar Osborne / Kaypro systems overall. Data General also brought out a small-footprint "Desktop Generation" range, starting with the DG10 that included both Data General and Intel CPUs in a patented closely coupled arrangement, able to run MS-DOS or CP/M-86 concurrently with DG/RDOS, with each benefiting from
5712-450: The hardware acceleration given by other CPU as a co-processor that would handle (for instance) screen graphics or disk operations concurrently. Other members of the Desktop Generation range, the DG20 and DG30, were aimed more at traditional commercial environments, such as multi-user COBOL systems, replacing refrigerator-sized minicomputers with toaster-sized modular microcomputers based around
5814-413: The initial devices used oxide-isolated metal gates, they were called CMOS (complementary metal–oxide–semiconductor logic). In contrast to TTL, CMOS uses almost no power in the static state (that is, when inputs are not changing). A CMOS gate draws no current other than leakage when in a steady 1 or 0 state. When the gate switches states, current is drawn from the power supply to charge the capacitance at
5916-474: The initial success of the Nova, Data General went public in the fall of 1969. The original Nova was soon followed by the faster SuperNova, which replaced the Nova's 4-bit arithmetic logic unit (ALU) with a 16-bit version that made the machine roughly four times as fast. Several variations and upgrades to the SuperNova core followed. The last major version, the Nova 4, was released in 1978. During this period
6018-461: The integrated-circuit devices. The most common logic family in modern semiconductor devices is metal–oxide–semiconductor (MOS) logic, due to low power consumption, small transistor sizes , and high transistor density . The list of packaged building-block logic families can be divided into categories, listed here in roughly chronological order of introduction, along with their usual abbreviations: The families (RTL, DTL, and ECL) were derived from
6120-705: The introduction of the RA series drives in December 1982 the Unibus was also used for high-speed peripherals. Both buses are provided by adapters that interface the bus to the SBI. All systems come with one Unibus as standard, with up to four supported. Massbus is optional, with up to four supported. The VAX-11/780 also supports Computer Interconnect (CI), a proprietary network to attach disk drives and potentially share them with other VAX computers. This feature can connect VAX computers in
6222-536: The logic circuits used in early computers, originally implemented using discrete components . One example is the Philips NORBIT family of logic building blocks. The PMOS and I L logic families were used for relatively short periods, mostly in special purpose custom large-scale integration circuits devices and are generally considered obsolete. For example, early digital clocks or electronic calculators may have used one or more PMOS devices to provide most of
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#17327867088386324-472: The logic families may use different voltage levels to represent 1 and 0 states, and may have other interface requirements only met within the logic family. TTL logic levels are different from those of CMOS – generally a TTL output does not rise high enough to be reliably recognized as a logic 1 by a CMOS input. This problem was solved by the invention of the 74HCT family of devices that uses CMOS technology but TTL input logic levels. These devices only work with
6426-500: The logic for the finished product. The F14 CADC , Intel 4004 , Intel 4040 , and Intel 8008 microprocessors and their support chips were PMOS. Of these families, only ECL, TTL, NMOS, CMOS, and BiCMOS are currently still in widespread use. ECL is used for very high-speed applications because of its price and power demands, while NMOS logic is mainly used in VLSI circuits applications such as CPUs and memory chips which fall outside of
6528-568: The logic gating function (e.g., AND) is performed by a diode network and the amplifying function is performed by a transistor. Diode logic was used with vacuum tubes in the earliest electronic computers in the 1940s including ENIAC . Diode–transistor logic (DTL) was used in the IBM 608 which was the first all-transistorized computer. Early transistorized computers were implemented using discrete transistors, resistors, diodes and capacitors. The first diode–transistor logic family of integrated circuits
6630-557: The logic thresholds are (approximately) proportional to power supply voltage, and not the fixed levels required by bipolar circuits. The required silicon area for implementing such digital CMOS functions has rapidly shrunk. VLSI technology incorporating millions of basic logic operations onto one chip, almost exclusively uses CMOS. The extremely small capacitance of the on-chip wiring caused an increase in performance by several orders of magnitude. On-chip clock rates as high as 4 GHz have become common, approximately 1000 times faster than
6732-433: The machines, not because they were forced; lock-in was over. De Castro agreed with the report, and future generations of the MV series were terminated. Instead, DG released a technically interesting series of Unix servers known as the AViiON . The name "AViiON" was a reversed play on the name of DG's first product, Nova, implying "Nova II". In an effort to keep costs down, the AViiON was originally designed and shipped with
6834-442: The meantime, customers were abandoning Data General in droves, driven not only by the delivery problems with the original Eclipse, including very serious quality control and customer service problems, but also the power and versatility of Digital's new VAX line. Ultimately, Fountainhead was cancelled and Eagle became the new MV series, with the first model, the Data General Eclipse MV/8000 , announced in April 1980. The Eagle Project
6936-537: The microECLIPSE CPUs and some of the technology developed for the microNOVA-based "Micro Products" range such as the MP/100 and MP/200 that had struggled to find a market niche. The Single-processor version of the DG10, the DG10SP, was the entry-level machine with, like the DG20 and 30, no ability to run Intel software. Despite having some good features and having less direct competition from the flood of cheap PC compatibles,
7038-496: The mid-1980s to become the preferred process for digital chips. ECL uses an overdriven bipolar junction transistor (BJT) differential amplifier with single-ended input and limited emitter current. The ECL family, ECL is also known as current-mode logic (CML), was invented by IBM as current steering logic for use in the transistorized IBM 7030 Stretch computer, where it was implemented using discrete components. The first ECL logic family to be available in integrated circuits
7140-418: The nascent relational database software DG/SQL . Data General also offered an office automation suite named Comprehensive Electronic Office (CEO), which included a mail system, a calendar, a folder-based document store, a word processor (CEOWrite), a spreadsheet processor, and other assorted tools. All were crude by today's standards, but were revolutionary for their time. CEOWrite was also offered on
7242-420: The original names for the VAX 8600 and VAX 8650 respectively. Data General Data General Corporation was one of the first minicomputer firms of the late 1960s. Three of the four founders were former employees of Digital Equipment Corporation (DEC). Their first product, 1969's Data General Nova , was a 16-bit minicomputer intended to both outperform and cost less than the equivalent from DEC,
7344-408: The original version. The introduction of Advanced Low-power Schottky (ALS) further increased speed and reduced power consumption. A faster logic family called FAST (Fairchild Advanced Schottky TTL) (Schottky) (F) was also introduced that was faster than normal Schottky TTL. CMOS logic gates use complementary arrangements of enhancement-mode N-channel and P-channel field effect transistor . Since
7446-572: The output of the gate. This means that the current draw of CMOS devices increases with switching rate (controlled by clock speed, typically). The first CMOS family of logic integrated circuits was introduced by RCA as CD4000 COS/MOS , the 4000 series , in 1968. Initially CMOS logic was slower than LS-TTL. However, because the logic thresholds of CMOS were proportional to the power supply voltage, CMOS devices were well-adapted to battery-operated systems with simple power supplies. CMOS gates can also tolerate much wider voltage ranges than TTL gates because
7548-539: The previous TTL family, a new standard emerged which combined the best of the TTL family with the advantages of the CD4000 family. It was known as the 74HC (which used anywhere from 3.3V to 5V power supplies (and used logic levels relative to the power supply)), and with devices that used 5V power supplies and TTL logic levels . Interconnecting any two logic families often required special techniques such as additional pull-up resistors , or purpose-built interface circuits, since
7650-399: The proprietary hardware business entirely. Thomas West 's report outlined these changes in the marketplace, and suggested that the customer was going to win the fight over lock-in. They also outlined a different solution: Instead of trying to compete against the much larger IBM and DEC, they suggested that since the user no longer cared about the hardware as much as software, DG could deliver
7752-412: The question of which machine was the "best" changed; it was no longer the machine with the best price–performance ratio or service contracts, but the one that ran all of the third-party software the customer intended to use. This change forced changes on the hardware vendors as well. Formerly, almost all computer companies attempted to make their machines different enough that when their customers sought
7854-452: The rapid commoditization of the Unix market led to shrinking sales. DG did begin a minor shift toward the service industry, training their technicians for the role of implementing a spate of new x86-based servers and the new Microsoft Windows NT domain-driven, small server world. This never developed enough to offset the loss of high margin server business however. Data General also targeted
7956-552: The same fashion as the processor issue, by running a large number of drives in parallel. The overall performance was greatly improved and the resulting innovation was marketed originally as the HADA (High Availability Disk Array) and then later as the CLARiiON line. The CLARiiON arrays, which offered SCSI RAID in various capacities, offered a great price/performance and platform flexibility over competing solutions. The CLARiiON line
8058-456: The same or a different program. Eventually, IDEA ran on every commercial hardware product from the MicroNova (4 users) to the MV series under AOS/VS, the same IDEA program running all those systems. The CS40 (the first of this line) was a package system which supported four terminal users, each running a different COBOL program. In 1979, DG introduced their Xodiac networking system. This
8160-497: The scope of this article. Present-day "building block" logic gate ICs are based on the ECL, TTL, CMOS, and BiCMOS families. Class of digital circuits built using resistors as the input network and bipolar junction transistors (BJTs) as switching devices. The Atanasoff–Berry Computer used resistor-coupled vacuum tube logic circuits similar to RTL. Several early transistorized computers (e.g., IBM 1620 , 1959) used RTL, where it
8262-724: The smaller, lighter D100, D200 and eventually the D210 replaced it as the basic user terminal, while graphics models such as the D460 (with ANSI X3.64 compatibility) occupied the very high end of the range. Terminal emulators for the D2/D3/D100/D200/D210 (and some features of the D450/460) do exist, including the Freeware 1993 DOS program in D460.zip. Most Data General software was written specifically for their own terminals (or
8364-441: The storage line, EMC quickly ended all development and production of DG computer hardware and parts, effectively ending Data General's presence in the segment. The maintenance business was sold to a third party, who also acquired all of DG's remaining hardware components for spare parts sales to old DG customers. The CLARiiON line continued to be a major player in the market and was marketed under that name until January 2012. CLARiiON
8466-423: The technology by 1970. CMOS chips often work with a broader range of power supply voltages than other logic families. Early TTL ICs required a power supply voltage of 5V, but early CMOS could use 3 to 15V. Lowering the supply voltage reduces the charge stored on any capacitances and consequently reduces the energy required for a logic transition. Reduced energy implies less heat dissipation. The energy stored in
8568-544: The terminal emulation built into the Desktop Generation DG10, but the Data General One built-in terminal emulator is not often suitable), although software using Data General Business BASIC could be more flexible in terminal handling, because logging into a Business BASIC system would initiate a process whereby the terminal type would (usually) be auto-detected. Data General's introduction of
8670-411: The years, with newer versions replacing the older types. Since the transistors of a standard TTL gate are saturated switches, minority carrier storage time in each junction limits the switching speed of the device. Variations on the basic TTL design are intended to reduce these effects and improve speed, power consumption, or both. The German physicist Walter H. Schottky formulated a theory predicting
8772-498: Was a straightforward, 32-bit extension of the Nova-based Eclipse. It was backwards-compatible with 16-bit Eclipse applications, used the same command-line interpreter, but offered improved 32-bit performance over the VAX 11/780 while using fewer components. By late 1979, it became clear that Eagle would deliver before Fountainhead, igniting an intense turf war within the company for constantly shrinking project funds. In
8874-553: Was also widely sold by Dell through a worldwide OEM deal with EMC. The Clariion and Celerra storage products evolved into EMC's unified storage platform, the VNX platform. Data General would be only one of many New England based computer companies, including the original Digital Equipment Corporation , that collapsed or were sold to larger companies after the 1980s. On the Internet, even the old Data General domain (dg.com), which contained
8976-531: Was based on the X.25 standard at the lower levels, and their own application layer protocols on top. Because it was based on X.25, remote sites could be linked together over commercial X.25 services like Telenet in the US or Datapac in Canada. Data General software packages supporting Xodiac included Comprehensive Electronic Office (CEO). In June 1987, Data General announced its intention to replace Xodiac with
9078-520: Was founded in Hudson, Massachusetts , in 1968. Harvey Newquist was hired from Computer Control Corporation to oversee manufacturing. Edson de Castro was the chief engineer in charge of the PDP-8 , DEC's line of inexpensive computers that created the minicomputer market. It was designed specifically to be used in laboratory equipment settings; as the technology improved, it was reduced in size to fit into
9180-530: Was implemented using discrete components. A family of simple resistor–transistor logic integrated circuits was developed at Fairchild Semiconductor for the Apollo Guidance Computer in 1962. Texas Instruments soon introduced its own family of RTL. A variant with integrated capacitors, RCTL, had increased speed, but lower immunity to noise than RTL. This was made by Texas Instruments as their "51XX" series. Class of digital circuits in which
9282-486: Was introduced by Motorola as MECL in 1962. In TTL logic, bipolar junction transistors perform the logic and amplifying functions. The first transistor–transistor logic family of integrated circuits was introduced by Sylvania as Sylvania Universal High–Level Logic (SUHL) in 1963. Texas Instruments introduced the 7400 series TTL family in 1964. Transistor–transistor logic uses bipolar transistors to form its integrated circuits. TTL has changed significantly over
9384-575: Was introduced by Signetics in 1962. DTL was also made by Fairchild and Westinghouse . A family of diode logic and diode–transistor logic integrated circuits was developed by Texas Instruments for the D-37C Minuteman II Guidance Computer in 1962, but these devices were not available to the public. A variant of DTL called "high-threshold logic" incorporated Zener diodes to create a large offset between logic 1 and logic 0 voltage levels. These devices usually ran off
9486-525: Was introduced in April 1984. Its KA785 CPU is essentially a faster KA780, with a CPU cycle time of 133 ns (7.52 MHz) versus the 200 ns (5 MHz) CPU cycle time of the KA780, giving a performance of 1.5 VUPs. The decrease in CPU cycle time is accomplished through use of Fairchild Advanced Schottky TTL (FAST) logic. The VAX-11/787 is a possible dual-processor variant of the VAX-11/785. It
9588-512: Was marketed not only to AViiON and Data General MV series customers, but also to customers running servers from other vendors such as Sun Microsystems , Hewlett-Packard and Silicon Graphics . Data General also embarked on a plan to hire storage sales specialists and to challenge the EMC Symmetrix in the wider market. On December 12, 1989, DG and Soviet Union software developer NPO Parma announced Perekat (Перекат, “Rolling Thunder,”)
9690-414: Was packaged on four PCB cards and was thus smaller in height, while also including a number of features that made it run considerably faster. Announced as "the best small computer in the world", the Nova quickly gained a following, especially in scientific and educational markets, and made the company flush with cash. DEC sued for misappropriation of its trade secrets, but this ultimately went nowhere. With
9792-514: Was released in 1969 by Data General as the Nova . The Nova, like the PDP-8, used a simple accumulator-based architecture . It lacked general registers and the stack-pointer functionality of the more advanced PDP-11 , as did competing products, such as the HP 1000 ; compilers used hardware-based memory locations in lieu of a stack pointer. Designed to be rack-mounted similarly to the later PDP-8 machines, it
9894-568: Was shipped in February 1978, however, Fountainhead was not yet ready to deliver a machine, due mainly to problems in project management. DG's customers left quickly for the VAX world. In the spring of 1978, with Fountainhead apparently in development hell , a secret skunkworks project was started to develop an alternative 32-bit system known as "Eagle" by a team led by Tom West . References to "the Eagle project" and "Project Eagle" co-exist. Eagle
9996-568: Was the United States Forest Service , which starting in the mid-1980s used DG systems installed at all levels from headquarters in Washington, D.C. down to individual ranger stations and fire command posts. This required equipment of high reliability and generally rugged construction that could be deployed in a wide range of places, often to be maintained and used by people with no computer background at all. The intent
10098-608: Was the only major customer. When Apple Computer and IBM proposed their joint solution based on POWER architecture , the PowerPC , Motorola picked up the manufacturing contract and killed the 88000. DG quickly responded by introduced new models of the AViiON series based on a true commodity processor, the Intel x86 series. By this time a number of other vendors, notably Sequent Computer Systems , were also introducing similar machines. The lack of lock-in now came back to haunt DG, and
10200-417: Was the subject of Tracy Kidder 's Pulitzer prize -winning book, The Soul of a New Machine , making the MV line the best-documented computer project in recent history. The MV systems generated an almost miraculous turnaround for Data General. Through the early 1980s sales picked up, and by 1984 the company had over a billion dollars in annual sales. One of Data General's significant customers at this time
10302-462: Was to combine CMOS inputs and TTL drivers to form of a new type of logic devices called BiCMOS logic , of which the LVT and ALVT logic families are the most important. The BiCMOS family has many members, including ABT logic , ALB logic , ALVT logic , BCT logic and LVT logic . With HC and HCT logic and LS-TTL logic competing in the market it became clear that further improvements were needed to create
10404-566: Was to create new kinds of functional integration in an agency that had long prized its decentralized structure. Despite some tensions, the implementation was effective and the overall effects on the agency notably positive. The introduction, implementation, and effects of the DG systems in USFS were documented in a series of evaluative reports prepared in the late 1980s by the RAND Corporation . The MV series came in various iterations, from
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