931:, who extensively developed the hardware during the 1980s and the Sigma 9 was operated commercially until c. 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. When Xerox withdrew from the mainframe computer manufacturing business and relinquished all assets to Honeywell Corporation, Comshare opened a Research and Development facility in Phoenix Arizona, where they manufactured three Sigma 9 systems from spare and remanufactured parts acquired from Modutest, Inc. of
408:
1785:, Section 6: Processors with multiprogramming ability, p.275. "The 940 uses a memory map which is almost a subset of that of Atlas but is more modest than that of the IBM 360/67 and GE 645 . A number of instructions are apparently built in via the programmed operator calling mechanism, based on Atlas extracodes (Chap. 23). The software-defined instructions emphasize the need for hardware features. For example, floating-point arithmetic is needed when several computer-bound programs are run. The SDS 945 is a successor to the 940, with slightly increased capability but at a lower cost."
303:, a major re-build of the 9xx line using integrated circuits (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 (equivalent to $ 1,045,000 in 2023). Cut-down versions of the 920 also followed, including the 12-bit
1636:, announced in May 1969, were small 16-bit computers designed primarily for process control applications. Both systems came with a base 4 KW of 16-bit core memory, expandable to 16 KW, and three "interrupt channels." The CE16 CPU can perform an addition in 16 ÎĽsec and a (software) multiplication in 126 ÎĽsec. Its price of $ 12,800 was equivalent to $ 106,349 in 2023. The CF16 CPU is rated at 5.33 ÎĽsec for addition and 42 ÎĽsec for (hardware) multiplication. It cost $ 14,900, equivalent to $ 123,797 in 2023.
27:
499:, 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
756:('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
1607:. 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
1611:
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
439:
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
451:
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. The
506:
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 Mod 9, Ilene Model 9000 and Real-time RCE-9 were designed, but it is not clear if they were ever
739:
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 alone 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
515:
Former SDS employees restarted the company with funding from Max
Palevsky, Sanford Kaplan, Dan McGurk, and others in 1979. Jack Mitchell, William L. Scheding, and Henry Harold, along with some other former SDS engineers introduced a microprocessor-based computer called the SDS-420 built on a
796:
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.
744:
had yet been completed. Mitchell alone 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.
1624:. 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.
734:
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
1598:
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
1616:
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.
671:
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.
655:. 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
675:
The SDS 4000 was a complete re-design, both cosmetically and with 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
731:(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.
659:
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.
545:
647:
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
2408:
1778:
771:
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
760:
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
352:
The SDS 92 is a small, high-speed, very low-cost, general purpose computer 12-bit system introduced in 1965. it was not compatible with other SDS lines such as the 900 series or the
792:
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
724:-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.
2403:
2393:
2398:
2388:
1176:
2148:
2293:
2002:
1747:
667:
In 1983 Ensor and Hill left Jacq-Rite and formed a company calling itself 'Scientific Data
Systems UK Limited' or 'SDS UK' (but actually unrelated to SDS) in
2413:
1743:'s "extracodes". The programmed operator calling mechanism allowed computer operation codes to be interpreted by software code. See Scientific Data Systems,
1930:
2418:
1091:
1956:. Columns: computer, solid state?, avg monthly rentals, date of 1st installation, number of installations, number of unfilled orders. 1974. p. 5577.
1889:
325:. 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
1088:(OCLC) Sigma6 with OCLC modifications to handle attached IBM 1403 printer and NCR 25 MB removable disks. OP/SYS Software updates by Phillip Long.
566:
The company sold about 1,000 machines worldwide, including Tahiti, London, Italy, New York City and Los
Angeles. The 400 Series had little to do with
2075:
1718:
1758:
601:
and was based upon a 10 MB hard disk manufactured by Micropolis of Chatsworth, California. SDS Offered other models, including the SDS-410, a
269:, 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
753:
2038:
2257:
1847:
1957:
1358:
1775:
1151:
767:
The 'unofficial' 4000 series machine was at least a finished computer, and the small number produced worked reliably. Taking advantage of the
2321:
2111:
1681:
1126:
273:
secondary storage. For scientific users writing small programs, this was a real boon and dramatically improved development turnaround time.
333:
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
171:
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
2117:
1687:
540:, California. The SDS-422 Model offered some of the first dual double-sided-double-density floppy drives. Other hardware options were a
1479:
1264:
349:
is generally accepted as the first commercial computer using monolithic integrated circuits. ICs were used on about 50 circuit cards.
318:
919:
Although initially intended as a Scientific Computer System, the 900 series and the Sigma series were used extensively in commercial
1924:
1883:
1100:
1337:
1807:
407:
2383:
1136:
1120:
2188:
1570:
1422:
1209:
1188:
251:
which included a hardware (integer) multiplier. These are arguably the first commercial systems based on silicon, rather than
1352:
1600:
1522:
1011:
948:
2220:
1528:
1282:
932:
710:
4000 SASI controller board was shoe-horned into the case to connect the drives. The diskette drive was also half-height
296:
to 32 kWords. Although its instruction format resembled that of the earlier machines, it was not compatible with them.
2140:
1765:, February 1970. Cf. Appendix E. page A-19, "Programmed Operators" for an in-depth discussion of Programmed Operators.
1740:
1645:
1582:
1452:
613:
155:
in computer design. The company concentrated on larger scientific workload focused machines and sold many machines to
2348:
2282:
1993:
1978:
1744:
1458:
1328:
984:
537:
521:
168:
2342:
1914:
1620:
Multiple simulators for the Sigma series are known to exist, and Sigma series software is being collected by the
1440:
1291:
1198:
1162:
1070:
1035:
495:
Even with these successes, when Xerox bought the company in 1969 they sold only about 1% of the computers in the
1901:
That same month Scientific Data Systems delivered the first commercial integrated circuit computer, the SDS-92.
1276:
1041:
533:
213:
140:
60:
1873:
1739:
A programmed operator was a hardware concept on the SDS 900 series of computers similar to the concept of the
1621:
1608:
1249:
1227:
1110:
1059:
988:
727:
The 4000's major aesthetic departure from its predecessor was the use of a separate 12-inch tilt-and-swivel
586:
445:
2064:
1464:
1446:
1322:
800:
SDS went out of business in the US 1984. The UK company of the same name ceased trading in the same year.
644:
605:
that booted and ran off the SDS-NET or optionally could boot off-of and run over a 1200 bit/s modem link.
412:
1836:
1710:
1604:
1182:
1168:
1156:
1145:
1114:
379:
201:
2027:
471:
The Sigma range was very successful in the niche real-time processing field, due to the sophisticated
2246:
1576:
1507:
1434:
1053:
668:
640:
609:
602:
594:
567:
1951:
1755:
752:. Several were even sold, including a 5-station network with external storage (see below) to the UK
1398:
973:
928:
789:
736:
621:
541:
517:
281:
1972:
1428:
1316:
962:
699:
695:
574:
472:
441:
152:
148:
144:
1032:
Company (Sigma 5/7 F-14A rear seat simulator aka 15C9A at Pacific Missile Test Center, Pt. Mugu)
456:, as a licensee of SDS, sold about 60 Sigma 7 machines in Europe, and developed an upgrade with
520:
processor design with up to 56 KB of memory and a proprietary OS, SDS-DOS, along with the
26:
2349:
Scientific Data Systems The Sigma Family: Introducing Sigma from Scientific Data Systems. 1967
2107:
2101:
1920:
1879:
1677:
1650:
1552:
1392:
1221:
Denver Aerospace Division (4 Sigma 7 for the MOL Program, SDS-930/Sigma 9 at Digidat division)
1106:
1065:
1000:
480:
292:, the 9300 only 1.75, almost 10 times as fast. The 9300 also increased maximum memory from 16
1671:
1020:(Sigma 5/7 F-14A front seat simulator aka 2F95A at Pacific Missile Test Center, Pt. Mugu, CA)
740:
unwittingly used schematics referring to a forthcoming revision of the machine, for which no
936:
899:
872:
868:
728:
625:
420:
353:
330:
221:
180:
128:
616:), and fully functional accounting software: balance-forward and open-item accounting with
196:
Throughout the majority of the 1960s the US computer market was dominated by "Snow White",
2325:
1782:
1762:
1751:
1377:
1303:
1257:
1218:
1202:
1079:
1029:
691:
639:
an early terminal emulation program using the 6551 USART. Through partnerships with their
503:
in July 1975 who produced Sigmas for a short period, and provided support into the 1980s.
461:
209:
370:
memory cycle) expandable to 4096, 8192, 16,384 or 32,768 words, all directly addressable
2353:
1803:
748:
The new machine worked, and a number of examples were made using a prototyping firm in
617:
457:
432:
2377:
1306:
Flight Training Center, Denver, Colorado (Sigma 5 LINK and Redifon flight Simulators)
1026:(Sigma 6) BTM for business and student records plus student online use. (Holland, MI)
1006:
749:
496:
310:
284:
for higher performance. The performance increase was dramatic; the 910/920 needed 16
270:
2184:
1633:
1546:
1410:
Dornier System ( Immenstaad Germany ) MUDAS- & CAMAC-cross-Assembler and other.
1270:
1023:
920:
608:
Products offered were: Word (word processing, written by John McCully, formerly of
590:
448:, it was designed to have specifications that were comparable to those of the 360.
395:
334:
314:
229:
132:
73:
163:. Most machines were both fast and relatively low-priced. The company was sold to
585:
in the early 1980s. SDS-NET was based on a Model 430 and written by Sam Keys, of
528:. The SDS-420 featured a dual single-sided-double-density (400 KB per side)
1613:
1501:
1230:
895:
891:
635:
Other offerings included: Legal Time and Billing, Medical Time and Billing, and
578:
560:
529:
453:
367:
285:
136:
258:
Additionally, the SDS machines shipped with a selection of software, notably a
1561:
1413:
1237:
656:
632:(written by Tom Davies and Sandra Mass, both formerly with Jacquard Systems).
237:
160:
2224:
1612:
does not appear to have survived. Copies of the original system developed at
232:
computer at just the right time. Much of their success was due to the use of
1534:
1516:
1386:
549:
525:
500:
252:
217:
374:
Peripheral equipment available from SDS standard peripheral line included:
147:, along with eleven other computer scientists. SDS was the first to employ
1495:
1310:
1297:
978:
924:
822:
741:
556:
383:
326:
293:
277:
262:
2368:
1573:(prev. University of Toronto Library Automation Systems) (Sigma 5, 7, 9)
1558:
AKU Studsvik (Sweden) (Dual Sigma 9 - Nuclear Power Station Simulators)
1130:
1017:
994:
834:
830:
826:
818:
814:
707:
648:
629:
476:
465:
322:
300:
289:
266:
259:
248:
244:
233:
1224:
Martin Marietta Dewey Rocky Mountain Cement, Lyons, Colorado (Sigma 2)
2363:
1343:
968:
940:
761:
757:
652:
582:
553:
552:
SDLC/HDLC chip and software patterned after the early Xerox 3.0
428:
424:
304:
255:, which offered much better reliability for no real additional cost.
241:
228:. SDS entered this well-developed market and was able to introduce a
205:
1349:
Space Data Corporation (Sigma 5 White Sands & Poker Flat Alaska)
1205:
with an AD 4 analog computer for projects like multiphase diffusion.
337:
and the same compute power, but it is unclear whether this shipped.
2358:
1243:
USAF Nellis AFB, Nevada (2 Sigma 9's NTTR Range Control Operations)
431:
Sigma 7, both using common hardware internally. The success of the
280:, announced in June 1963. Among other changes, the 9300 included a
944:
793:
598:
532:
drive, Model 70, manufactured by PerSci (Peripheral Sciences), of
436:
406:
164:
1473:
1085:
1075:
768:
703:
484:
156:
1564:
Vällingby (Sweden) (Dual Sigma 9 - Electricity Grid Monitoring)
1240:, Nevada (6 Sigma 9's ACEVAL/AIMVAL Project CUBIC ACMI systems)
1050:
Los Angeles County Roads (Sigma 3 traffic light control system)
225:
197:
2338:
981:(Sigma 5/7, Los Angeles District 5 freeway monitoring center)
1913:
Pugh, Emerson W.; Johnson, Lyle R.; Palmer, John H. (1991).
475:
structure and independent I/O processor. The first node of
468:. CII also manufactured and sold some 160 Sigma 2 systems.
1395:(Wharton) (Dual Sigma 5 - MRCA (Tornado) Flight Telemetry)
1246:
US Navy Yuma Arizona "Top Gun" CUBIC ACMI System (Sigma 5)
1185:(Sigma 3 RTM) (Life testing appliances, Benton Harbor, MI)
1513:
SMRE - Safety in Mines Research Establishment - Sheffield
1498:
Boscombe Down (Sigma 5 - MRCA (Tornado) Flight Telemetry)
1215:
Exploration Data Consultants Lakewood Colorado (Sigma 5)
839:
first design, shipped along with the 920 in August 1962
2103:
Achieving Accuracy: A Legacy of Computers and Missiles
1754:, technical manual. Cf. Programmed Operator. Also see
1531:
North England (Sigma 2, 3, 5 - Chemical Plant Control)
1094:(Sigma 7) - In Temp 1 building into at least the 1980s
954:
Other known users of SDS systems in the USA include:
570:
and more with word processing and business services.
2292:. Vol. 2, no. 8. August 1969. p. 61.
849:
930 with additional support for time sharing (1966)
843:
high performance 920 with FPU and more memory (1963)
2256:. Vol. 15, no. 5. May 1969. p. 193.
1875:
The U.S. computer industry: a study of market power
1038:, Pasadena (Sigma 5/7, Deep Space Center, bldg 230)
706:interface (still known as SASI at the time) and an
643:(VARs) other software product offerings included a
313:developed a segmentation and relocation system for
110:
85:
66:
44:
36:
2065:"ANNUAL HISTORICAL REVIEW KWAJALEIN MISSILE RANGE"
1525:Munich (Sigma 5 - MRCA (Tornado) Flight Telemetry)
702:removable drive units. The 4000 motherboard had a
1804:"The Computer That Will Not Die: The SDS SIGMA 7"
1519:Turin (Sigma 5 - MRCA (Tornado) Flight Telemetry)
1142:University of Texas at Austin (910, 930, Sigma 5)
1103:(RIT) (Sigma 6 academic/administrative computing)
1585:Tsuruga Japan (Sigma 5 - Nuclear Core Simulator)
2409:Defunct computer companies of the United States
1579:(Sigma 5 with Honeywell memory mapping upgrade)
1165:(Sigma 5/7 data reduction system at South Base)
1044:, Experimental Particle Physics Group (Sigma 7)
2339:Oral history interview with Paul A. Strassmann
2214:
2212:
2210:
2208:
2206:
1555:Aircraft (Israel) (Sigma 5 - Flight Telemetry)
1177:Washington Metropolitan Area Transit Authority
419:In December 1966 SDS shipped the entirely new
2359:SDS 900 series documentation at bitsavers.org
1288:Naval Nuclear Lab Idaho Falls Idaho (Sigma 5)
386:) with or without paper tape reader and punch
8:
1776:"Computer Structures: Readings and Examples"
1129:(UCLA) (Sigma 7) "The first computer on the
1003:(Sigma 7, Hybrid Simulation Lab, Goleta, CA)
31:Logo of the company during most of the 1970s
19:
2364:Sigma series documentation at bitsavers.org
2178:
2176:
2174:
2172:
2170:
2168:
2166:
2141:"SDS Resurfaces With Same Name, New Target"
1294:, Cloudcroft, New Mexico (Sigma 2, Sigma 5)
1092:Queens College, City University of New York
1831:
1829:
1827:
1825:
1567:West Chester University (Sigma 9 and X560)
548:and a proprietary network SDS-NET using a
382:(characters per second) Keyboard/printer (
25:
18:
2404:Computer companies disestablished in 1984
2394:American companies disestablished in 1984
1797:
1795:
1793:
1791:
1407:Cybernetics Research Consultants (Slough)
1346:, Ponca City, Oklahoma (Sigma 7, Sigma 9)
1300:, Scottsdale, Arizona (Sigma 5, Sigma 9)
1201:research lab was running a Sigma 5 as a
807:
440:other ways, such as its use of multiple
167:in 1969, but dwindling sales due to the
2369:Tymshare documentation at bitsavers.org
2008:from the original on September 24, 2014
1662:
1603:was released, which was developed into
2399:Computer companies established in 1961
2389:American companies established in 1961
2345:, University of Minnesota, Minneapolis
2151:from the original on September 9, 2023
1970:
1721:from the original on February 15, 2020
1690:from the original on December 17, 2022
1461:(550 - Submarine Power Plant Research)
1369:Known users outside the U.S. include:
1359:Lawrence Livermore National Laboratory
1047:Los Alamos Scientific Laboratory (930)
969:Central Illinois Light Company (CILCO)
947:used 910s in the 1960s to control its
2191:from the original on February 6, 2015
1992:Scientific Data Systems (June 1965).
1543:American Israeli Paper Mills (Israel)
1380:(Sigma 2 & 3 - Flight Simulation)
1127:University of California, Los Angeles
563:produced by Tat Lam of the Bay Area.
7:
2283:"Technology Profile: Mini-Computers"
2106:. Xlibris Corporation. p. 104.
1431:(Sigma 5 - Braille Printer Research)
1086:Online Computer Library Center, Inc.
845:less expensive but faster 920 (1964)
2414:Defunct computer hardware companies
2120:from the original on August 7, 2020
2100:McMurran, Marshall William (2008).
1853:from the original on March 27, 2020
1510:Department of Engineering (Sigma 6)
1482:, AKA Ministry of Public Buildings)
1419:Rank Radio International (Plymouth)
1191:(A/D Flight simulation, Dayton, OH)
923:systems. The biggest such user was
507:produced past the prototype stage.
299:In December 1963 SDS announced the
276:The 910 and 920 were joined by the
2419:Defunct computer systems companies
2299:from the original on July 18, 2023
2263:from the original on July 18, 2023
2044:from the original on July 11, 2020
1878:. Ballinger Pub. Co. p. 192.
1480:National Gas Turbine Establishment
1313:, Arizona (Sigma 5 LINK Simulator)
1265:University of Southern Mississippi
788:However, the UK company's lack of
573:SDS announced a fully operational
321:, which was commercialized in the
319:University of California, Berkeley
14:
2354:SDS Sigma 7 technical information
2139:Rosenberg, Marcy (Feb 12, 1979).
2081:from the original on July 9, 2020
1953:The Industrial Reorganization Act
1152:University of Wisconsin–Green Bay
1101:Rochester Institute of Technology
698:10 and 20 MB hard drives or
597:services over SDS-NET or using a
1995:Reference Manual SDS 92 Computer
1810:from the original on 25 May 2011
1670:Gregory, Nathan (Mar 16, 2018).
1334:Dallas Power and Light (Sigma 5)
1137:University of Texas at Arlington
1123:(UCI) Computing Center (Sigma 7)
1121:University of California, Irvine
939:. Recognition Equipment Inc. of
1960:from the original on 2023-08-13
1933:from the original on 2023-08-13
1916:IBM's 360 and Early 370 Systems
1892:from the original on 2022-12-17
1423:Royal Naval Engineering College
1273:, Seattle, Washington (Sigma 3)
1252:, Burbank, California (Sigma 7)
1210:United States Air Force Academy
1189:Wright-Patterson Air Force Base
240:in their earliest designs, the
2147:. Vol. XIII, no. 7.
1802:Keith G. Calkins (June 1984).
1353:Los Alamos National Laboratory
151:, and was an early adopter of
1:
1437:(Sigma 2 - Particle Research)
1285:, Boulder, Colorado (SDS-940)
1173:Warner Computer Systems, Inc.
1012:Grand Valley State University
949:optical character recognition
754:Institute of Legal Executives
589:. The SDS 430 Server offered
366:2048-word basic memory (1.75
139:and Robert Beck, veterans of
131:founded in September 1961 by
1325:, Phoenix, Arizona (Sigma 5)
1319:, Phoenix, Arizona (Sigma 2)
1283:National Bureau of Standards
935:and Modutest Systems, Inc.,
933:Westlake Village, California
487:with an SDS Sigma 7 system.
2328:, Friday, February 24, 1967
1646:Berkeley Timesharing System
1583:Mitsubishi Heavy Industries
1492:Watsons (Insurance) Redhill
1453:University College Hospital
1107:Stanford Research Institute
987:(CMU) (Sigma 5, now at the
614:Manhattan Beach, California
415:, Seattle, Washington, 2014
363:12-bit word plus parity bit
360:12- and 24-bit instructions
200:, and the "Seven Dwarves",
179:), whose machines were the
50:; 63 years ago
2435:
2028:"Graduate Studies Catalog"
1919:. MIT Press. p. 440.
1756:"SDS 910 Reference Manual"
1504:(Sigma 9 flight simulator)
1489:
1459:Rolls-Royce and Associates
1374:
1329:Tennessee Valley Authority
1195:
985:Carnegie Mellon University
959:
522:BASIC programming language
435:and the rise of the 7-bit
2343:Charles Babbage Institute
1872:Brock, Gerald W. (1975).
1837:"SDS 92 Reference Manual"
1709:Scientific Data Systems.
1383:Link Simulation (Lansing)
1292:Sunspot Solar Observatory
1261:research vessel (Sigma 2)
1199:Youngstown Sheet and Tube
1163:Vandenberg Air Force Base
1071:Michigan State University
1036:Jet Propulsion Laboratory
860:"low end" machine (1965)
663:SDS in the United Kingdom
389:300 cps paper tape reader
24:
16:American computer company
1632:The Xerox CE16 and CF16
1338:Carolina Power and Light
1277:Montana State University
1042:Johns Hopkins University
1018:Grumman Aircraft Company
1014:(Sigma 6, Allendale, MI)
307:, and the IC-based 925.
282:floating point processor
214:Control Data Corporation
141:Packard Bell Corporation
61:Santa Monica, California
2384:Scientific Data Systems
1622:Computer History Museum
1609:Computer History Museum
1267:, Hattiesburg (Sigma 9)
1250:Hughes Aircraft Company
1111:The Mother of All Demos
1097:Robert Plan Corporation
1078:(Sigma 5 and Sigma 7 -
989:Computer History Museum
587:Westchester, California
392:60 cps paper tape punch
121:Scientific Data Systems
20:Scientific Data Systems
2247:"controller/computers"
1977:: CS1 maint: others (
1447:Charing Cross Hospital
1441:Addenbrooke's Hospital
1323:Arizona Public Service
1271:Pacific Bell Telephone
1060:Marquardt Aircraft Co.
997:(Sigma 9) Columbus, IN
645:solid-waste management
416:
413:Living Computer Museum
411:An XDS Sigma 9 at the
317:use on the 930 at the
1169:Vanderbilt University
1157:University of Wyoming
1146:University of Vermont
1080:Pioneer Space Project
847:major redesign (1963)
641:value-added resellers
410:
356:. Features included:
169:oil crisis of 1973–74
2322:"Enter Max Palevsky"
2185:"Former Sigma sites"
1577:Dalhousie University
1508:Cambridge University
1435:Liverpool University
1298:Motorola Electronics
1233:, Colorado (Sigma 3)
1054:Marquette University
794:Personal Computer/AT
669:Crawley, West Sussex
603:diskless workstation
568:scientific computing
423:, starting with the
398:Magnetic Tape System
1478:N.G.T.E. Pyestock (
1465:St Thomas' Hospital
1399:Carleton University
1389:Engineering (Epsom)
1279:, Bozeman (Sigma 7)
974:Bucknell University
929:Ann Arbor, Michigan
737:reverse-engineering
729:Visual Display Unit
622:Accounts Receivable
479:was established by
153:integrated circuits
149:silicon transistors
127:), was an American
21:
2219:Kirkpatrick, Jim.
2072:Nautilus Institute
1781:2008-12-26 at the
1761:2011-01-17 at the
1750:2008-12-18 at the
1676:Lulu. p. 85.
1673:The Tym Before ...
1540:Rank Xerox (Milan)
1470:Government Chemist
1429:Warwick University
1344:Conoco Corporation
1317:Salt River Project
1062:, Van Nuys, Calif.
995:Cummins Engine Co.
963:Andrews University
581:called SDS-NET at
575:local area network
473:hardware interrupt
417:
288:to add two 24-bit
173:Xerox Data Systems
114:Xerox Data Systems
2227:on April 21, 2021
2113:978-1-4363-8107-9
2063:Spin, William A.
1844:www.bitsavers.org
1683:978-1-387-30405-9
1651:SDS 9xx computers
1591:
1590:
1404:Comshare (London)
1393:British Aerospace
1367:
1366:
1109:(SRI) (used for "
1066:McDonnell Douglas
912:
911:
481:Leonard Kleinrock
118:
117:
2426:
2309:
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2223:. Archived from
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2201:
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2198:
2196:
2183:Calkins, Keith.
2180:
2161:
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1799:
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1766:
1745:"SDS 900 Series"
1737:
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1726:
1711:"SDS 900 series"
1706:
1700:
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1667:
1372:
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957:
956:
937:Phoenix, Arizona
808:
784:
783:
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776:
723:
722:
718:
715:
689:
688:
684:
681:
626:Accounts Payable
610:Jacquard Systems
464:capability, the
427:Sigma 2 and the
331:circuit-switched
222:General Electric
181:Xerox 500 series
129:computer company
102:
100:
58:
56:
51:
29:
22:
2434:
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2316:Further reading
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2221:"The Sigma Era"
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2011:
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1773:
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1752:Wayback Machine
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1642:
1630:
1596:
1378:British Airways
1304:United Airlines
1258:Glomar Explorer
1219:Martin Marietta
1203:Hybrid computer
1139:(UTA) (Sigma 7)
1030:Hughes Aircraft
917:
907:
905:
900:Xerox Sigma 8/9
898:
894:
882:
880:
876:CE16 & CF16
875:
871:
848:
846:
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842:
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833:
829:
825:
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806:
804:Computer models
781:
777:
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713:
711:
692:hard disk drive
686:
682:
679:
677:
665:
595:printer sharing
513:
493:
452:French company
444:rather than an
405:
343:
265:, developed by
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106:
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81:
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2333:External links
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1774:Bell, Gordon,
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1115:oN-Line System
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888:32-bit systems
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865:16-bit systems
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812:
811:24-bit systems
805:
802:
785:-inch drives.
664:
661:
618:General Ledger
538:Marina del Rey
512:
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462:dual-processor
458:virtual memory
433:IBM System/360
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896:SDS Sigma 6/7
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23:
2301:. Retrieved
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2265:. Retrieved
2253:
2241:
2229:. Retrieved
2225:the original
2193:. Retrieved
2153:. Retrieved
2144:
2134:
2122:. Retrieved
2102:
2095:
2083:. Retrieved
2071:
2058:
2046:. Retrieved
2035:UW-Green bay
2034:
2022:
2010:. Retrieved
1994:
1987:
1962:. Retrieved
1952:
1946:
1935:. Retrieved
1915:
1908:
1900:
1894:. Retrieved
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1867:
1855:. Retrieved
1843:
1812:. Retrieved
1770:
1735:
1723:. Retrieved
1714:
1704:
1692:. Retrieved
1672:
1665:
1631:
1619:
1597:
1594:SDS software
1547:Israeli Navy
1368:
1256:
1024:Hope College
953:
921:time-sharing
918:
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766:
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607:
577:(LAN)-based
572:
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561:transceivers
534:Santa Monica
514:
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491:Xerox models
470:
450:
421:Sigma series
418:
403:Sigma series
373:
354:Sigma series
351:
346:
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315:time-sharing
309:
298:
286:microseconds
275:
257:
230:time-sharing
195:
176:
172:
133:Max Palevsky
124:
120:
119:
74:Max Palevsky
2290:Modern Data
1614:UC Berkeley
1502:RAE Bedford
1443:(Cambridge)
1231:Buckley AFB
1159:(Sigma 5/7)
915:Known users
892:SDS Sigma 5
873:SDS Sigma 3
869:SDS Sigma 2
579:file server
530:floppy disk
518:6502A-based
511:A new start
446:accumulator
238:transistors
159:during the
137:Arthur Rock
78:Robert Beck
2378:Categories
2254:Datamation
2195:August 29,
1964:2020-12-04
1937:2020-12-04
1896:2020-12-04
1657:References
1562:Vattenfall
1414:Rank Xerox
1238:Nellis AFB
951:machines.
161:Space Race
1973:cite book
1857:March 16,
1715:yumpu.com
1537:(Algeria)
1535:Sonatrach
1517:Aeritalia
1496:A&AEE
1425:(Manadon)
1401:(Sigma 9)
1387:WS Atkins
1361:(Sigma 7)
1355:(Sigma 2)
1340:(Sigma 5)
1331:(Sigma 5)
1212:(Sigma 5)
1183:Whirlpool
1148:(Sigma 7)
1113:" on the
1056:(Sigma 9)
965:(Sigma 7)
526:Microsoft
501:Honeywell
442:registers
253:germanium
218:Honeywell
202:Burroughs
111:Successor
40:Computers
2303:July 18,
2294:Archived
2267:July 18,
2258:Archived
2231:July 17,
2189:Archived
2149:Archived
2118:Archived
2076:Archived
2039:Archived
2003:Archived
1958:Archived
1931:Archived
1890:Archived
1848:Archived
1808:Archived
1779:Archived
1759:Archived
1748:Archived
1719:Archived
1688:Archived
1640:See also
1485:J. Sefel
1467:(London)
1455:(London)
1449:(London)
1416:(Denham)
1311:Luke AFB
979:Caltrans
927:Inc. of
925:Comshare
823:SDS 9300
742:firmware
557:Ethernet
384:teletype
327:Tymshare
290:integers
278:SDS 9300
263:compiler
67:Founders
37:Industry
2085:July 9,
2048:July 9,
2012:Sep 20,
1725:Feb 15,
1694:Feb 15,
1179:(WMATA)
1131:ARPANET
908:(1971)
835:SDS 940
831:SDS 930
827:SDS 925
819:SDS 920
815:SDS 910
790:capital
780:⁄
719:⁄
708:Adaptec
700:SyQuest
696:Seagate
685:⁄
657:Lloyd's
649:Dorking
630:Payroll
477:ARPANET
466:Iris 80
323:SDS 940
301:SDS 930
267:Digitek
260:FORTRAN
249:SDS 920
245:SDS 910
236:-based
234:silicon
187:History
97: (
86:Defunct
53: (
45:Founded
2155:Nov 6,
2124:Jul 9,
2110:
1923:
1882:
1814:15 May
1680:
941:Dallas
906:(1966)
904:(1967)
881:(1969)
879:(1966)
857:SDS 92
841:
762:MS-DOS
758:IBM PC
690:-inch
653:Surrey
628:, and
583:COMDEX
554:Mbit/s
429:32-bit
425:16-bit
396:MAGPAK
347:SDS 92
341:SDS 92
305:SDS 92
294:kWords
242:24-bit
224:, and
206:UNIVAC
145:Bendix
2297:(PDF)
2286:(PDF)
2261:(PDF)
2250:(PDF)
2079:(PDF)
2068:(PDF)
2042:(PDF)
2031:(PDF)
2006:(PDF)
1999:(PDF)
1851:(PDF)
1840:(PDF)
1571:UTLAS
1549:(560)
1309:USAF
1236:USAF
1001:Delco
945:Texas
883:1969
599:modem
550:Z8530
546:USART
524:from
437:ASCII
165:Xerox
2305:2023
2269:2023
2233:2023
2197:2013
2157:2015
2126:2020
2108:ISBN
2087:2020
2050:2020
2014:2014
1979:link
1921:ISBN
1880:ISBN
1859:2019
1816:2011
1727:2020
1696:2020
1678:ISBN
1605:CP-V
1474:GCHQ
1228:USAF
1208:The
1076:NASA
769:SCSI
704:SCSI
593:and
591:file
559:and
542:6551
536:and
485:UCLA
460:and
368:ÎĽsec
345:The
247:and
157:NASA
143:and
99:1984
95:1984
92:1975
55:1961
48:1961
1601:UTS
1553:IAF
1529:ICI
1523:MBB
764:.)
637:TTY
544:-A
483:at
454:CII
380:cps
378:10
335:I/O
329:'s
226:RCA
210:NCR
204:,
198:IBM
177:XDS
125:SDS
59:in
2380::
2341:,
2324:,
2288:.
2252:.
2205:^
2187:.
2165:^
2143:.
2116:.
2074:.
2070:.
2037:.
2033:.
2001:.
1975:}}
1971:{{
1929:.
1899:.
1888:.
1846:.
1842:.
1824:^
1806:.
1790:^
1717:.
1713:.
1686:.
943:,
651:,
624:,
620:,
612:,
220:,
216:,
212:,
208:,
183:.
135:,
2307:.
2271:.
2235:.
2199:.
2159:.
2128:.
2089:.
2052:.
2016:.
1981:)
1967:.
1940:.
1861:.
1818:.
1729:.
1698:.
1133:"
1082:)
991:)
782:4
778:1
775:+
773:5
721:4
717:1
714:+
712:5
687:4
683:1
680:+
678:5
175:(
123:(
101:)
57:)
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