Scientific Data Systems
Encyclopedia
Scientific Data Systems, or SDS, was an American
computer
company founded in September 1961 by Max Palevsky
, a veteran of Packard Bell
and Bendix
, along with eleven other computer scientists. SDS was an early adopter of integrated circuit
s in computer design and the first to employ silicon
transistors. The company concentrated on larger scientific workload focused machines and sold many machines to NASA
during the Space Race
. Most machines were both fast and relatively low priced. The company was sold to Xerox
in 1969, but mismanagement and dwindling sales caused Xerox to close the division in 1975 at a loss of hundreds of millions of dollars. During the Xerox years the company was officially Xerox Data Systems, or XDS.
) and the Seven Dwarves, NCR
, Burroughs, Control Data Corporation
, General Electric
, Honeywell
, RCA
and UNIVAC
. SDS entered this well developed market and soon carved out their own niche, a surprising development. Much of this success was due to the use of silicon
-based transistors in their earliest designs, the 24-bit
SDS 910 and SDS 920 which included a hardware (integer) multiplier. These are arguably the first commercial systems based on silicon, which offered much better performance for no real additional cost. Additionally the SDS machines shipped with a selection of software, notably a FORTRAN
compiler, developed by Digitek
, that made use of the systems' Programmed OPeratorS (POPS), and could compile, in 4K 24-bit words, programs in a single pass without the need for magnetic tape
secondary storage. For scientific users writing small programs, this was a real boon and dramatically improved development turnaround time.
The 910 and 920 were supplanted by the SDS 9300, announced in June 1963. Among other changes, the 9300 included a floating point processor
for higher performance. The performance increase was dramatic, the 910/920 needed 16 microseconds to add two 24-bit integers, the 9300 only 1.75, almost 10 times as fast. The 9300 also increased maximum memory from 16 kWords to 32 kWords. Although its instruction format resembled that of the earlier machines, it was not compatible with them.
In December 1963 SDS announced the SDS 930
, a major re-build of the 9xx line using ICs in the central processor. It was comparable to the 9300 in basic operations, but was generally slower overall due to the lack of the 9300's memory interlace capability and hardware floating point unit (although a hardware floating point "correlation and filtering unit" was available as an expensive option). The 930 cost less than half that of the original 9300, at about $105,000. Cut-down versions of the 920 also followed, including the 12-bit SDS 92, and the IC-based 925.
Project Genie
developed a segmentation and relocation system for time sharing use at the University of California, Berkeley
resulting in the SDS 940
. It had additional hardware for relocation and swapping of memory sections, and interruptible instructions. The 940 would go on to be a major part of Tymshare
's circuit-switched network system growth in the 1960s (pre-ARPAnet and before packet-switching). A 945 was announced in July 1968 as a modified 940 with less I/O
and the same compute power, but it is unclear whether this shipped.
In December 1966 SDS shipped the entirely new Sigma series, starting with the 16-bit
Sigma 2 and the 32-bit
Sigma 7, both using common hardware internally. The success of the IBM System/360 and the rise of the 7-bit ASCII
character standard was pushing all vendors to the 8-bit standard from their earlier 6-bit ones. SDS was one of the first companies to offer a machine intended as an alternative to the IBM System/360; although not compatible with the 360, it used similar data formats, the EBCDIC character code, and in other ways, such as its use of multiple registers rather than an accumulator, it was designed to have specifications that were comparable to those of the 360. Various versions of the Sigma 7 followed, including the cut-down Sigma 5 and re-designed Sigma 6. The Xerox Sigma 9 was a major re-design with instruction lookahead and other advanced features, while the Sigma 8 and Sigma 9 mod 3 were low-end machines offered as a migration path for the Sigma 5. Meanwhile, the French national champion CII, as licencee of SDS, sold about 60 Sigma 7 in Europe, and developed an upgrade with virtual memory and biprocessor capability, Iris 80. CII also manufactured and sold some 160 Sigma 2.
The Sigma range was very successful in the niche real-time processing field, due to the sophisticated hardware interrupt structure and independent I/O processor. The first node of ARPANET was established by Leonard Kleinrock
at UCLA with an SDS Sigma 7 system.
Even with these successes, when Xerox bought the company in 1969 they sold only about 1% of the computers in the US, something Xerox never seemed to improve. When they were purchased, about 1,000 SDS machines of all types were in the market, and by the time the division closed in 1975 this had increased to only about 2,100. By this point the newer Xerox 550 and 560 models, extensively re-designed Sigmas, were about to come to market and were extensively back ordered. Most rights were sold to Honeywell
in July, 1975 who produced Sigmas for a short period, and provided support into the 1980s.
Several manufacturers attempted to enter the Sigma 9 replacement market. The first successful design was the Telefile T-85, but it is not clear how many were sold. Other efforts, including the Modutest Model 9, Ilene Model 9000 and Real-time RCE-9 were designed, but it is not clear if they were ever produced past the prototype stage.
The 400 Series had little to do with scientific computing and more with word processing and business services. The company sold about 1000 machines worldwide, including Tahiti, London, Italy, New York City and Los Angeles.
SDS announced at COMDEX, in the early 1980s, its SDS NET a fully operational local area network (LAN) based file server (Model 430) (written by Sam Keys, of Westchester, CA). The SDS-430-Server offered file and print-sharing services over SDS-NET or modems and was based upon a 10MB hard disk manufactured by Micropolis of Chatsworth, CA. SDS Offered other models, including the SDS-410, a diskless work station that booted and ran off the SDS-NET or optionally could boot off-of and run over a 1200 bit/s modem link.
Products offered were: Word (word processing, written by John McCully, formerly of Jacuard Systems, Manhattan Beach, CA.), and fully functional accounting software: balance-forward and open-item accounting with GL, AR, AP, & Payroll (written by Tom Davies and Sandra Mass, both formerly with Jaquard Systems).
Other offerings included: Legal Time and Billing, Medical Time and Billing, and TTY an early terminal emulation program using the 6551 USART. Through partnerships with their VARS (Value Added Resellers) other software product offerings included a solid-waste management system with automated truck routing and a country-club accounting package. One UK-based VAR was Jacq-Rite, a vertical market software house run by Ken Groome and Vivienne Gurney and based in Dorking, Surrey. Jacq-Rite had developed a range of specialist insurance software for the Jacquard machine but transferred to the SDS 400 following the advice of John McCully. Jacq-Rite installed several SDS 400 series networks in Lloyd's Managing and Members Agencies during 1982 and 1983. One of Jacq-Rite's programming staff that worked on the software porting was Justin Hill. Jacq-Rite's hardware sales were managed by David Ensor.
The SDS 4000 was a complete re-design cosmetically, and had all-new internal hardware but the architecture was basically the same as the 400 series - and ran the same software. The machine had a 1/2 height 5 1/4 inch hard drive bay and used Seagate 10 and 20MB hard drives or Syquest removable drive units. The 4000 motherboard had a SCSI interface (still known as SASI at the time) and a Adaptec 4000 SASI controller board was shoe-horned into the case to connect the drives. The diskette drive was also half-height 5 1/4 inch (the 400 series had used 8 inch diskettes). Like the 410, there was a diskless version too. Local Area Networking capabilities were carried over from the 400 series.
The 4000's major aesthetic departure from its predecessor was the use of a separate 12-inch tilt-and-swivel VDU and CPU case. The keyboard was detachable for the first time and the system had a beige colour scheme (dictated by the colour of the third party VDUs) in place of the black and white appearance of the 400.
However, financial problems at SDS were already substantial and the UK business only ever received a small number of hastily-completed machines. In an attempt to bypass these problems Hill produced a clone of the 4000 series computer by reverse-engineering an original model with the aid of a set of paper schematics obtained on a visit to SDS. This was neither approved nor supported by SDS but Mitchell and Scheding made a confidential visit to the UK to help debug the new computer. This was fortunate because, being unable to confer with SDS, Hill had unwittingly used schematics referring to a forthcoming revision of the machine, for which no firmware had yet been completed. Mitchell and Scheding finished the new firmware at SDS UK's offices. This meant that Hill's 'unofficial 4000' was actually a later revision than any US machines completed. Hill also improved the board layout, rear-panel connectivity and power supply.
The new machine worked and a number of examples were made using a prototyping firm in Poole, Dorset. Several were even sold, including a 5 station network with external storage (see below) to the UK Institute of Legal Executives ('ILEX') in Bedford which remained in use for several years. This was supplied with bespoke software (also produced by Hill, with the assistance of Paula Flint) to store examination results and print certificates. However, any hope of selling into the lucrative Lloyd's insurance market in conjunction with Jacq-Rite was short-lived as Jacq-Rite had abandoned SDS and moved to the IBM PC platform, taking their customers with them, as soon as SDS UK was formed. (This decision was also influenced by John McCully, who was now developing his word-processing software for MS-DOS.)
The 'unofficial' 4000 series machine was at least a finished computer and the small number produced worked reliably. Taking advantage of the SCSI implementation, Hill added an external connector to his version of the machine and developed a matching hard drive enclosure. This enclosure accommodated higher capacity, full-height 5 1/4 inch drives.
However, the UK company's lack of capital to invest in the machine's manufacture meant that the cosmetic appearance of the computer left a lot to be desired. Furthermore the machines were extremely costly - IBM's new Personal Computer/AT was shipping at about half the price SDS UK Limited needed to sell their computer for. Relationships between SDS and its UK namesake had broken down completely by this time and SDS UK did not have the resources to develop new versions of the hardware or operating system.
SDS went out of business in 1984. The UK company of the same name ceased trading in the same year.
Other known users outside the U.S. include:
was released, which was developed into CP-V. The RBM operating system was replaced by CP-R, a real-time and timesharing system.
In March 1982 Honeywell gave the remaining software for the 900 series to a group in Kansas City that offered to continue making copies for people still using the systems. Honeywell had
stopped supporting the systems many years before this. In September 2006, this collection was donated to the Computer History Museum
along with all of the program's original
documentation, and copies of most of the SDS user's manuals. This is one of the largest collections of software to have survived from the 1960s intact. Unfortunately, the timesharing software for the 940 series was not present in the Honeywell LADS Library and does not appear to have survived. Copies of the original system developed at UC Berkeley exist as file system
backups. Most of the customers for 940 systems (in particular Tymshare) made extensive modifications to the 940 system software, and no copies of that version of the software are known
to have survived.
A simulator for the Sigma series is known to exist, and Sigma series software is being collected by the Computer History Museum
. Early versions were not copyrighted (CP-V C00 and earlier), while later versions developed by Honeywell were (CP-V E00 and F00). Some copies of CP-V D00 were released without licensing agreements and subsequently public domain status was claimed by users.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
computer
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...
company founded in September 1961 by Max Palevsky
Max Palevsky
Max Palevsky was an American art collector, venture capitalist, philanthropist, and computer technology pioneer.-Early life:...
, a veteran of Packard Bell
Packard Bell
Packard Bell is a Dutch computer manufacturer and a subsidiary of Acer. The name was previously used by Packard Bell, an American radio manufacturer founded in 1926. In 1986, Israeli investors bought the name for a newly formed personal computer manufacturer. Originally the company produced...
and Bendix
Bendix
- People :* Bendix Hallenstein - New Zealand businessman* Henry Bendix - fictional character from Wildstorm comics* John E. Bendix - American Civil War and New York Guard general* Max Bendix - American composer, conductor, violinist* Reinhard Bendix - sociologist...
, along with eleven other computer scientists. SDS was an early adopter of integrated circuit
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...
s in computer design and the first to employ silicon
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
transistors. The company concentrated on larger scientific workload focused machines and sold many machines to NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
during the Space Race
Space Race
The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...
. Most machines were both fast and relatively low priced. The company was sold to Xerox
Xerox
Xerox Corporation is an American multinational document management corporation that produced and sells a range of color and black-and-white printers, multifunction systems, photo copiers, digital production printing presses, and related consulting services and supplies...
in 1969, but mismanagement and dwindling sales caused Xerox to close the division in 1975 at a loss of hundreds of millions of dollars. During the Xerox years the company was officially Xerox Data Systems, or XDS.
History
Throughout the majority of the 1960s the US computer market was dominated by Snow White (IBMIBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
) and the Seven Dwarves, NCR
NCR Corporation
NCR Corporation is an American technology company specializing in kiosk products for the retail, financial, travel, healthcare, food service, entertainment, gaming and public sector industries. Its main products are self-service kiosks, point-of-sale terminals, automated teller machines, check...
, Burroughs, Control Data Corporation
Control Data Corporation
Control Data Corporation was a supercomputer firm. For most of the 1960s, it built the fastest computers in the world by far, only losing that crown in the 1970s after Seymour Cray left the company to found Cray Research, Inc....
, General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
, Honeywell
Honeywell
Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....
, RCA
RCA
RCA Corporation, founded as the Radio Corporation of America, was an American electronics company in existence from 1919 to 1986. The RCA trademark is currently owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor...
and UNIVAC
UNIVAC
UNIVAC is the name of a business unit and division of the Remington Rand company formed by the 1950 purchase of the Eckert-Mauchly Computer Corporation, founded four years earlier by ENIAC inventors J. Presper Eckert and John Mauchly, and the associated line of computers which continues to this day...
. SDS entered this well developed market and soon carved out their own niche, a surprising development. Much of this success was due to the use of silicon
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
-based transistors in their earliest designs, the 24-bit
24-bit
Notable 24-bit machines include the ICT 1900 series and the Harris H series.The IBM System/360, announced in 1964, was a popular computer system with 24-bit addressing and 32-bit general registers and arithmetic...
SDS 910 and SDS 920 which included a hardware (integer) multiplier. These are arguably the first commercial systems based on silicon, which offered much better performance for no real additional cost. Additionally the SDS machines shipped with a selection of software, notably a FORTRAN
Fortran
Fortran is a general-purpose, procedural, imperative programming language that is especially suited to numeric computation and scientific computing...
compiler, developed by Digitek
Digitek
Digitek was an early system software company located in Los Angeles, California.Digitek, co-founded in the early 1960s by three equal partners Digitek was an early system software company located in Los Angeles, California.Digitek, co-founded in the early 1960s by three equal partners Digitek was...
, that made use of the systems' Programmed OPeratorS (POPS), and could compile, in 4K 24-bit words, programs in a single pass without the need for magnetic tape
Magnetic tape
Magnetic tape is a medium for magnetic recording, made of a thin magnetizable coating on a long, narrow strip of plastic. It was developed in Germany, based on magnetic wire recording. Devices that record and play back audio and video using magnetic tape are tape recorders and video tape recorders...
secondary storage. For scientific users writing small programs, this was a real boon and dramatically improved development turnaround time.
The 910 and 920 were supplanted by the SDS 9300, announced in June 1963. Among other changes, the 9300 included a floating point processor
Floating point unit
A floating-point unit is a part of a computer system specially designed to carry out operations on floating point numbers. Typical operations are addition, subtraction, multiplication, division, and square root...
for higher performance. The performance increase was dramatic, the 910/920 needed 16 microseconds to add two 24-bit integers, the 9300 only 1.75, almost 10 times as fast. The 9300 also increased maximum memory from 16 kWords to 32 kWords. Although its instruction format resembled that of the earlier machines, it was not compatible with them.
In December 1963 SDS announced the SDS 930
SDS 930
The SDS 930 was a commercial computer using bipolar junction transistors sold by Scientific Data Systems.It was announced in December 1963, with first installations in June 1964.-Description:An SDS 930 system consisted of at least three standard The SDS 930 was a commercial computer using bipolar...
, a major re-build of the 9xx line using ICs in the central processor. It was comparable to the 9300 in basic operations, but was generally slower overall due to the lack of the 9300's memory interlace capability and hardware floating point unit (although a hardware floating point "correlation and filtering unit" was available as an expensive option). The 930 cost less than half that of the original 9300, at about $105,000. Cut-down versions of the 920 also followed, including the 12-bit SDS 92, and the IC-based 925.
Project Genie
Project Genie
Project Genie was a computer research project started in 1964 at the University of California, Berkeley.It produced an early time-sharing system including the Berkeley Timesharing System, which was then commercialized as the SDS 940.-History:...
developed a segmentation and relocation system for time sharing use at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
resulting in the SDS 940
SDS 940
The SDS 940 was Scientific Data Systems' first machine designed to support time sharing directly, and was based on the SDS 930's 24-bit CPU built primarily of integrated circuits. It was announced in February 1966 and shipped in April, becoming a major part of Tymshare's expansion during the 1960s...
. It had additional hardware for relocation and swapping of memory sections, and interruptible instructions. The 940 would go on to be a major part of Tymshare
Tymshare
Tymshare, Inc. was headquartered in Cupertino, California from 1964 to 1984.It was a well-known timesharing service and third-party hardware maintenance company throughout its history and competed with companies such as Four Phase, Compuserve, and Digital Equipment Corporation...
's circuit-switched network system growth in the 1960s (pre-ARPAnet and before packet-switching). A 945 was announced in July 1968 as a modified 940 with less I/O
Input/output
In computing, input/output, or I/O, refers to the communication between an information processing system , and the outside world, possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it...
and the same compute power, but it is unclear whether this shipped.
In December 1966 SDS shipped the entirely new Sigma series, starting with the 16-bit
16-bit
-16-bit architecture:The HP BPC, introduced in 1975, was the world's first 16-bit microprocessor. Prominent 16-bit processors include the PDP-11, Intel 8086, Intel 80286 and the WDC 65C816. The Intel 8088 was program-compatible with the Intel 8086, and was 16-bit in that its registers were 16...
Sigma 2 and the 32-bit
32-bit
The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295. Hence, a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory....
Sigma 7, both using common hardware internally. The success of the IBM System/360 and the rise of the 7-bit ASCII
ASCII
The American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
character standard was pushing all vendors to the 8-bit standard from their earlier 6-bit ones. SDS was one of the first companies to offer a machine intended as an alternative to the IBM System/360; although not compatible with the 360, it used similar data formats, the EBCDIC character code, and in other ways, such as its use of multiple registers rather than an accumulator, it was designed to have specifications that were comparable to those of the 360. Various versions of the Sigma 7 followed, including the cut-down Sigma 5 and re-designed Sigma 6. The Xerox Sigma 9 was a major re-design with instruction lookahead and other advanced features, while the Sigma 8 and Sigma 9 mod 3 were low-end machines offered as a migration path for the Sigma 5. Meanwhile, the French national champion CII, as licencee of SDS, sold about 60 Sigma 7 in Europe, and developed an upgrade with virtual memory and biprocessor capability, Iris 80. CII also manufactured and sold some 160 Sigma 2.
The Sigma range was very successful in the niche real-time processing field, due to the sophisticated hardware interrupt structure and independent I/O processor. The first node of ARPANET was established by Leonard Kleinrock
Leonard Kleinrock
Leonard Kleinrock is an American engineer and computer scientist. A computer science professor at UCLA's Henry Samueli School of Engineering and Applied Science, he made several important contributions to the field of computer networking, in particular to the theoretical side of computer networking...
at UCLA with an SDS Sigma 7 system.
Even with these successes, when Xerox bought the company in 1969 they sold only about 1% of the computers in the US, something Xerox never seemed to improve. When they were purchased, about 1,000 SDS machines of all types were in the market, and by the time the division closed in 1975 this had increased to only about 2,100. By this point the newer Xerox 550 and 560 models, extensively re-designed Sigmas, were about to come to market and were extensively back ordered. Most rights were sold to Honeywell
Honeywell
Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....
in July, 1975 who produced Sigmas for a short period, and provided support into the 1980s.
Several manufacturers attempted to enter the Sigma 9 replacement market. The first successful design was the Telefile T-85, but it is not clear how many were sold. Other efforts, including the Modutest Model 9, Ilene Model 9000 and Real-time RCE-9 were designed, but it is not clear if they were ever produced past the prototype stage.
A new start
In 1979 Jack Mitchell, William L. Scheding, and Henry Harold, former SDS engineers, along with some other ex-SDS people re-started the company with funding from Max Palevsky, Sanford Kaplan, Dan McGurk, and others. They introduced a microprocessor based computer called the SDS-420 built on a 6502A-based processor design with up to 56KB of memory and a proprietary OS, SDS-DOS, along with the BASIC programming language, Inc. The SDS-420 featured a dual single-sided-double-density (400KB per side) floppy drive, Model 70, manufactured by PerSci (Peripheral Sciences), of Santa Monica and Marina Del rey, CA. The SDS-422 Model offered some of the first dual double-sided-double-density floppy drives. Other hardware options were a 6551-A USART and a proprietary network SDS-NET using an 8530 SDLC/HDLC chip and software patterned after the early Xerox 3.0 Mbit/s ethernet and tranceivers produced by Tat Lam of the Bay Area.The 400 Series had little to do with scientific computing and more with word processing and business services. The company sold about 1000 machines worldwide, including Tahiti, London, Italy, New York City and Los Angeles.
SDS announced at COMDEX, in the early 1980s, its SDS NET a fully operational local area network (LAN) based file server (Model 430) (written by Sam Keys, of Westchester, CA). The SDS-430-Server offered file and print-sharing services over SDS-NET or modems and was based upon a 10MB hard disk manufactured by Micropolis of Chatsworth, CA. SDS Offered other models, including the SDS-410, a diskless work station that booted and ran off the SDS-NET or optionally could boot off-of and run over a 1200 bit/s modem link.
Products offered were: Word (word processing, written by John McCully, formerly of Jacuard Systems, Manhattan Beach, CA.), and fully functional accounting software: balance-forward and open-item accounting with GL, AR, AP, & Payroll (written by Tom Davies and Sandra Mass, both formerly with Jaquard Systems).
Other offerings included: Legal Time and Billing, Medical Time and Billing, and TTY an early terminal emulation program using the 6551 USART. Through partnerships with their VARS (Value Added Resellers) other software product offerings included a solid-waste management system with automated truck routing and a country-club accounting package. One UK-based VAR was Jacq-Rite, a vertical market software house run by Ken Groome and Vivienne Gurney and based in Dorking, Surrey. Jacq-Rite had developed a range of specialist insurance software for the Jacquard machine but transferred to the SDS 400 following the advice of John McCully. Jacq-Rite installed several SDS 400 series networks in Lloyd's Managing and Members Agencies during 1982 and 1983. One of Jacq-Rite's programming staff that worked on the software porting was Justin Hill. Jacq-Rite's hardware sales were managed by David Ensor.
SDS in the UK
In 1983 Ensor and Hill walked out of Jacq-Rite and formed a company calling itself 'Scientific Data Systems UK Limited' or 'SDS UK' (but actually unrelated to SDS) in Crawley, West Sussex in the UK. This coincided with SDS's announcement of their 4000 series computer; they hoped to build a business around this machine (including supplying it to Jacq-Rite) and negotiated an exclusive arrangement with SDS.The SDS 4000 was a complete re-design cosmetically, and had all-new internal hardware but the architecture was basically the same as the 400 series - and ran the same software. The machine had a 1/2 height 5 1/4 inch hard drive bay and used Seagate 10 and 20MB hard drives or Syquest removable drive units. The 4000 motherboard had a SCSI interface (still known as SASI at the time) and a Adaptec 4000 SASI controller board was shoe-horned into the case to connect the drives. The diskette drive was also half-height 5 1/4 inch (the 400 series had used 8 inch diskettes). Like the 410, there was a diskless version too. Local Area Networking capabilities were carried over from the 400 series.
The 4000's major aesthetic departure from its predecessor was the use of a separate 12-inch tilt-and-swivel VDU and CPU case. The keyboard was detachable for the first time and the system had a beige colour scheme (dictated by the colour of the third party VDUs) in place of the black and white appearance of the 400.
However, financial problems at SDS were already substantial and the UK business only ever received a small number of hastily-completed machines. In an attempt to bypass these problems Hill produced a clone of the 4000 series computer by reverse-engineering an original model with the aid of a set of paper schematics obtained on a visit to SDS. This was neither approved nor supported by SDS but Mitchell and Scheding made a confidential visit to the UK to help debug the new computer. This was fortunate because, being unable to confer with SDS, Hill had unwittingly used schematics referring to a forthcoming revision of the machine, for which no firmware had yet been completed. Mitchell and Scheding finished the new firmware at SDS UK's offices. This meant that Hill's 'unofficial 4000' was actually a later revision than any US machines completed. Hill also improved the board layout, rear-panel connectivity and power supply.
The new machine worked and a number of examples were made using a prototyping firm in Poole, Dorset. Several were even sold, including a 5 station network with external storage (see below) to the UK Institute of Legal Executives ('ILEX') in Bedford which remained in use for several years. This was supplied with bespoke software (also produced by Hill, with the assistance of Paula Flint) to store examination results and print certificates. However, any hope of selling into the lucrative Lloyd's insurance market in conjunction with Jacq-Rite was short-lived as Jacq-Rite had abandoned SDS and moved to the IBM PC platform, taking their customers with them, as soon as SDS UK was formed. (This decision was also influenced by John McCully, who was now developing his word-processing software for MS-DOS.)
The 'unofficial' 4000 series machine was at least a finished computer and the small number produced worked reliably. Taking advantage of the SCSI implementation, Hill added an external connector to his version of the machine and developed a matching hard drive enclosure. This enclosure accommodated higher capacity, full-height 5 1/4 inch drives.
However, the UK company's lack of capital to invest in the machine's manufacture meant that the cosmetic appearance of the computer left a lot to be desired. Furthermore the machines were extremely costly - IBM's new Personal Computer/AT was shipping at about half the price SDS UK Limited needed to sell their computer for. Relationships between SDS and its UK namesake had broken down completely by this time and SDS UK did not have the resources to develop new versions of the hardware or operating system.
SDS went out of business in 1984. The UK company of the same name ceased trading in the same year.
Known users
Although initially intended as a Scientific Computer System, the Sigma series and the 900 series was used extensively as a Commercial Time Sharing System. The biggest such user was Comshare Inc, Ann Arbor, MI who extensively developed the hardware during the 1980s and the Sigma 9 was operated commercially until approx 1993. Developments and improvements by Comshare included the I-Channel which allowed the utilization of Bus/Tag (IBM compatible) devices and the ISI Communications interface. These innovations allowed Comshare to capitalize on the Sigma CPU's and their software development (Commander II) by gaining access to current technology storage systems. Recognition Equipment (Dallas, TX) used 910s in the 1960s to control its optical reading machines.Other known users outside the U.S. include:
- British Airways (Sigma 2 & 3 - Flight Simulation)
- Link Simulation (Lansing)
- WS Atkins Engineering (Epsom)
- British Aerospace (Wharton) (Dual Sigma 5 - MRCA (Tornado) Flight Telemetry)
- Comshare (London)
- Cybernetics Research Consultants (Slough)
- Rank Xerox (Denham)
- Rank Radio International (Plymouth)
- Royal Naval Engineering College (Manadon)
- Warwick University (Sigma 5 - Braille Printer Research)
- Liverpool University (Sigma 2 - Particle Research)
- Addenbrookes Hospital (Cambridge)
- Charing Cross Hospital (London)
- University College Hospital (London)
- Rolls Royce and Associates (550 - Submarine Power Plant Research)
- St. Thomas Hospital (London)
- Government Chemist
- GCHQ
- N.G.T.E. Pyestock (National Gas Turbine Establishment, AKA Ministry of Public Buildings))
- J.Sefel
- Watsons (Insurance) Redhill
- A&AEE Boscombe Down (Sigma 5 - MRCA (Tornado) Flight Telemetry)
- RAE Bedford (Sigma 9 flight simulator)
- Cambridge university department of engineering Sigma 7
- SMRE - Safety in Mines Research Establishment - Sheffield
- Aeritalia Turin (Sigma 5 - MRCA (Tornado) Flight Telemetry)
- MBB Munich (Sigma 5 - MRCA (Tornado) Flight Telemetry)
- ICI North England (Sigma 2, 3, 5 - Chemical Plant Control)
- Sonatrach (Algeria)
- Rank Xerox (Milan)
- American Israeli Paper Mills (Israel)
- Israeli Navy (560)
- IAF Aircraft (Israel) (Sigma 5 - Flight Telemetry)
- AKU Studsvik (Sweden) (Dual Sigma 9 - Nuclear Power Station Simulators)
- West Chester University
- NASA (Sigma 5 and Sigma 7 - Pioneer Space Project)
SDS Software
The primary operating system for the 900 series was called Monarch. For the Sigma 32-bit range RBM, a real-time and batch monitor, and BTM, a batch and timesharing monitor were available. In 1971 a more sophisticated timesharing system UTS/XOSUniversal Time-Sharing System
-UTS:The Universal Time-Sharing System was an operating system for the XDS Sigma line of computers, succeeding BTM/BPM. UTS was announced in 1966, but because of delays did not actually ship until 1971...
was released, which was developed into CP-V. The RBM operating system was replaced by CP-R, a real-time and timesharing system.
In March 1982 Honeywell gave the remaining software for the 900 series to a group in Kansas City that offered to continue making copies for people still using the systems. Honeywell had
stopped supporting the systems many years before this. In September 2006, this collection was donated to the Computer History Museum
Computer History Museum
The Computer History Museum is a museum established in 1996 in Mountain View, California, USA. The Museum is dedicated to preserving and presenting the stories and artifacts of the information age, and exploring the computing revolution and its impact on our lives.-History:The museum's origins...
along with all of the program's original
documentation, and copies of most of the SDS user's manuals. This is one of the largest collections of software to have survived from the 1960s intact. Unfortunately, the timesharing software for the 940 series was not present in the Honeywell LADS Library and does not appear to have survived. Copies of the original system developed at UC Berkeley exist as file system
backups. Most of the customers for 940 systems (in particular Tymshare) made extensive modifications to the 940 system software, and no copies of that version of the software are known
to have survived.
A simulator for the Sigma series is known to exist, and Sigma series software is being collected by the Computer History Museum
Computer History Museum
The Computer History Museum is a museum established in 1996 in Mountain View, California, USA. The Museum is dedicated to preserving and presenting the stories and artifacts of the information age, and exploring the computing revolution and its impact on our lives.-History:The museum's origins...
. Early versions were not copyrighted (CP-V C00 and earlier), while later versions developed by Honeywell were (CP-V E00 and F00). Some copies of CP-V D00 were released without licensing agreements and subsequently public domain status was claimed by users.
Computer models
- SDS 910 - first design, shipped along with the 920 in August 1962
- SDS 920
- SDS 9300 - high performance 920 with FPU and more memory
- SDS 92 - 12-bit "low end" machine
- SDS 925 - less expensive but faster 920
- SDS 930SDS 930The SDS 930 was a commercial computer using bipolar junction transistors sold by Scientific Data Systems.It was announced in December 1963, with first installations in June 1964.-Description:An SDS 930 system consisted of at least three standard The SDS 930 was a commercial computer using bipolar...
- major redesign - SDS 940SDS 940The SDS 940 was Scientific Data Systems' first machine designed to support time sharing directly, and was based on the SDS 930's 24-bit CPU built primarily of integrated circuits. It was announced in February 1966 and shipped in April, becoming a major part of Tymshare's expansion during the 1960s...
- 930 with additional support for time sharing - Xerox Sigma 8/9
- SDS Sigma 6/7
- SDS Sigma 5
- SDS Sigma 3
- SDS Sigma 2
- Xerox 530
- Xerox 560
Further reading
- "Enter Max Palevsky", Time MagazineTime (magazine)Time is an American news magazine. A European edition is published from London. Time Europe covers the Middle East, Africa and, since 2003, Latin America. An Asian edition is based in Hong Kong...
, Friday, February 24, 1967
External links
- Oral history interview with Paul A. Strassmann, Charles Babbage InstituteCharles Babbage InstituteThe Charles Babbage Institute is a research center at the University of Minnesota specializing in the history of information technology, particularly the history since 1935 of digital computing, programming/software, and computer networking....
, University of Minnesota, Minneapolis - Scientific Data Systems The Sigma Family: Introducing Sigma from Scientific Data Systems. 1967
- SDS Sigma 7 technical information
- SDS 900 series documentation at bitsavers.org
- Sigma series documentation at bitsavers.org
- Tymshare documentation at bitsavers.org