942:, 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
419:
1796:, 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."
314:, 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
1647:, 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.
38:
510:, 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
767:('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
1618:. 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
1622:
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
450:
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
462:
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
517:
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
750:
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
526:
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
807:
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.
755:
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.
1635:. 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.
745:
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
1609:
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
1627:
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.
682:
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.
666:. 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
686:
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
742:(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.
670:
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.
658:
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
1789:
782:
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
771:
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
363:
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
803:
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
735:-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.
556:
2419:
1070:
2159:
2304:
2013:
1758:
678:
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
1754:'s "extracodes". The programmed operator calling mechanism allowed computer operation codes to be interpreted by software code. See Scientific Data Systems,
1941:
1967:. Columns: computer, solid state?, avg monthly rentals, date of 1st installation, number of installations, number of unfilled orders. 1974. p. 5577.
1900:
2414:
2404:
336:. 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
1099:(OCLC) Sigma6 with OCLC modifications to handle attached IBM 1403 printer and NCR 25 MB removable disks. OP/SYS Software updates by Phillip Long.
577:
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
2086:
605:
1729:
1769:
612:
and was based upon a 10 MB hard disk manufactured by Micropolis of Chatsworth, California. SDS Offered other models, including the SDS-410, a
280:, 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
2409:
2399:
2049:
2268:
1858:
1968:
1187:
1786:
778:
The 'unofficial' 4000 series machine was at least a finished computer, and the small number produced worked reliably. Taking advantage of the
2332:
284:
secondary storage. For scientific users writing small programs, this was a real boon and dramatically improved development turnaround time.
2424:
344:
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
182:
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
2429:
2128:
1102:
1698:
551:, California. The SDS-422 Model offered some of the first dual double-sided-double-density floppy drives. Other hardware options were a
360:
is generally accepted as the first commercial computer using monolithic integrated circuits. ICs were used on about 50 circuit cards.
930:
Although initially intended as a Scientific Computer System, the 900 series and the Sigma series were used extensively in commercial
1818:
764:
2199:
1369:
262:
which included a hardware (integer) multiplier. These are arguably the first commercial systems based on silicon, rather than
2122:
1692:
1162:
1137:
2231:
721:
4000 SASI controller board was shoe-horned into the case to connect the drives. The diskette drive was also half-height
1490:
1275:
329:
307:
to 32 kWords. Although its instruction format resembled that of the earlier machines, it was not compatible with them.
17:
2151:
1776:, February 1970. Cf. Appendix E. page A-19, "Programmed Operators" for an in-depth discussion of Programmed Operators.
166:
in computer design. The company concentrated on larger scientific workload focused machines and sold many machines to
2359:
1935:
1894:
1348:
1111:
2394:
2293:
2004:
1755:
1147:
1131:
1925:
1631:
Multiple simulators for the Sigma series are known to exist, and Sigma series software is being collected by the
1581:
1433:
1220:
1199:
506:
Even with these successes, when Xerox bought the company in 1969 they sold only about 1% of the computers in the
1912:
That same month Scientific Data Systems delivered the first commercial integrated circuit computer, the SDS-92.
1363:
1884:
1750:
A programmed operator was a hardware concept on the SDS 900 series of computers similar to the concept of the
1611:
1022:
959:
1533:
738:
The 4000's major aesthetic departure from its predecessor was the use of a separate 12-inch tilt-and-swivel
1539:
1293:
943:
2075:
811:
SDS went out of business in the US 1984. The UK company of the same name ceased trading in the same year.
616:
that booted and ran off the SDS-NET or optionally could boot off-of and run over a 1200 bit/s modem link.
1847:
1751:
1721:
1656:
1593:
1463:
624:
418:
1989:
1469:
1339:
995:
548:
532:
2038:
482:
The Sigma range was very successful in the niche real-time processing field, due to the sophisticated
2353:
2257:
1451:
1302:
1209:
1173:
1081:
1046:
179:
1962:
1766:
763:. Several were even sold, including a 5-station network with external storage (see below) to the UK
1287:
1052:
544:
224:
151:
71:
1632:
1619:
1260:
1238:
1121:
999:
597:
456:
1043:
Company (Sigma 5/7 F-14A rear seat simulator aka 15C9A at Pacific Missile Test Center, Pt. Mugu)
467:, as a licensee of SDS, sold about 60 Sigma 7 machines in Europe, and developed an upgrade with
1475:
1457:
1333:
655:
531:
processor design with up to 56 KB of memory and a proprietary OS, SDS-DOS, along with the
423:
2360:
Scientific Data Systems The Sigma Family: Introducing Sigma from Scientific Data Systems. 1967
2112:
1232:
Denver Aerospace Division (4 Sigma 7 for the MOL Program, SDS-930/Sigma 9 at Digidat division)
303:, the 9300 only 1.75, almost 10 times as fast. The 9300 also increased maximum memory from 16
1682:
1615:
1193:
1179:
1167:
1156:
1125:
1031:(Sigma 5/7 F-14A front seat simulator aka 2F95A at Pacific Missile Test Center, Pt. Mugu, CA)
751:
unwittingly used schematics referring to a forthcoming revision of the machine, for which no
390:
212:
1587:
1518:
1445:
1064:
679:
651:
627:), and fully functional accounting software: balance-forward and open-item accounting with
620:
613:
578:
207:
Throughout the majority of the 1960s the US computer market was dominated by "Snow White",
650:
an early terminal emulation program using the 6551 USART. Through partnerships with their
514:
in July 1975 who produced Sigmas for a short period, and provided support into the 1980s.
8:
1409:
984:
939:
800:
747:
632:
552:
528:
292:
381:
memory cycle) expandable to 4096, 8192, 16,384 or 32,768 words, all directly addressable
2364:
1983:
1814:
1439:
1327:
973:
759:
The new machine worked, and a number of examples were made using a prototyping firm in
710:
706:
585:
483:
452:
163:
159:
155:
2118:
1931:
1890:
1688:
1661:
1563:
1403:
1317:
Flight Training Center, Denver, Colorado (Sigma 5 LINK and Redifon flight Simulators)
1117:
1076:
1037:(Sigma 6) BTM for business and student records plus student online use. (Holland, MI)
1011:
491:
295:
for higher performance. The performance increase was dramatic; the 910/920 needed 16
2195:
1421:
Dornier System ( Immenstaad Germany ) MUDAS- & CAMAC-cross-Assembler and other.
947:
910:
883:
879:
739:
636:
619:
Products offered were: Word (word processing, written by John McCully, formerly of
459:, it was designed to have specifications that were comparable to those of the 360.
431:
364:
341:
232:
191:
139:
406:
174:. Most machines were both fast and relatively low-priced. The company was sold to
2336:
1793:
1773:
1762:
1388:
1314:
1268:
1229:
1213:
1090:
1040:
702:
596:
in the early 1980s. SDS-NET was based on a Model 430 and written by Sam Keys, of
539:. The SDS-420 featured a dual single-sided-double-density (400 KB per side)
472:
220:
646:
Other offerings included: Legal Time and Billing, Medical Time and Billing, and
628:
468:
443:
269:
Additionally, the SDS machines shipped with a selection of software, notably a
37:
643:(written by Tom Davies and Sandra Mass, both formerly with Jacquard Systems).
2388:
2235:
1623:
does not appear to have survived. Copies of the original system developed at
1017:
760:
507:
321:
281:
243:
computer at just the right time. Much of their success was due to the use of
1644:
1557:
1281:
1034:
931:
601:
385:
Peripheral equipment available from SDS standard peripheral line included:
345:
325:
240:
158:, along with eleven other computer scientists. SDS was the first to employ
143:
84:
1624:
1512:
1241:
906:
902:
589:
571:
540:
464:
378:
296:
147:
2379:
1584:(prev. University of Toronto Library Automation Systems) (Sigma 5, 7, 9)
1572:
1569:
AKU Studsvik (Sweden) (Dual Sigma 9 - Nuclear Power Station Simulators)
1424:
1248:
667:
248:
171:
1235:
Martin Marietta Dewey Rocky Mountain Cement, Lyons, Colorado (Sigma 2)
2374:
1545:
1527:
1397:
563:
SDLC/HDLC chip and software patterned after the early Xerox 3.0
560:
536:
511:
266:, which offered much better reliability for no real additional cost.
263:
239:. SDS entered this well-developed market and was able to introduce a
228:
1360:
Space Data Corporation (Sigma 5 White Sands & Poker Flat Alaska)
1216:
with an AD 4 analog computer for projects like multiphase diffusion.
348:
and the same compute power, but it is unclear whether this shipped.
2369:
1506:
1321:
1308:
1254:
USAF Nellis AFB, Nevada (2 Sigma 9's NTTR Range Control Operations)
989:
935:
833:
752:
567:
442:
Sigma 7, both using common hardware internally. The success of the
394:
337:
304:
291:, announced in June 1963. Among other changes, the 9300 included a
288:
273:
543:
drive, Model 70, manufactured by PerSci (Peripheral Sciences), of
1141:
1028:
1005:
845:
841:
837:
829:
825:
718:
659:
640:
487:
476:
333:
311:
300:
277:
270:
259:
255:
244:
1575:
Vällingby (Sweden) (Dual Sigma 9 - Electricity Grid Monitoring)
1354:
1251:, Nevada (6 Sigma 9's ACEVAL/AIMVAL Project CUBIC ACMI systems)
1061:
Los Angeles County Roads (Sigma 3 traffic light control system)
979:
951:
772:
768:
663:
593:
564:
439:
435:
315:
252:
216:
2349:
992:(Sigma 5/7, Los Angeles District 5 freeway monitoring center)
955:
804:
609:
447:
175:
1924:
Pugh, Emerson W.; Johnson, Lyle R.; Palmer, John H. (1991).
1484:
1096:
1086:
779:
714:
495:
486:
structure and independent I/O processor. The first node of
479:. CII also manufactured and sold some 160 Sigma 2 systems.
167:
1406:(Wharton) (Dual Sigma 5 - MRCA (Tornado) Flight Telemetry)
1257:
US Navy Yuma Arizona "Top Gun" CUBIC ACMI System (Sigma 5)
1196:(Sigma 3 RTM) (Life testing appliances, Benton Harbor, MI)
1524:
SMRE - Safety in Mines Research Establishment - Sheffield
1509:
Boscombe Down (Sigma 5 - MRCA (Tornado) Flight Telemetry)
236:
208:
1226:
Exploration Data Consultants Lakewood Colorado (Sigma 5)
2002:
850:
first design, shipped along with the 920 in August 1962
2114:
Achieving Accuracy: A Legacy of Computers and Missiles
1765:, technical manual. Cf. Programmed Operator. Also see
1542:
North England (Sigma 2, 3, 5 - Chemical Plant Control)
1105:(Sigma 7) - In Temp 1 building into at least the 1980s
965:
Other known users of SDS systems in the USA include:
581:
and more with word processing and business services.
2303:. Vol. 2, no. 8. August 1969. p. 61.
860:
930 with additional support for time sharing (1966)
854:
high performance 920 with FPU and more memory (1963)
2267:. Vol. 15, no. 5. May 1969. p. 193.
1886:
The U.S. computer industry: a study of market power
1719:
1049:, Pasadena (Sigma 5/7, Deep Space Center, bldg 230)
717:interface (still known as SASI at the time) and an
654:(VARs) other software product offerings included a
324:developed a segmentation and relocation system for
2076:"ANNUAL HISTORICAL REVIEW KWAJALEIN MISSILE RANGE"
1536:Munich (Sigma 5 - MRCA (Tornado) Flight Telemetry)
713:removable drive units. The 4000 motherboard had a
1923:
1815:"The Computer That Will Not Die: The SDS SIGMA 7"
1530:Turin (Sigma 5 - MRCA (Tornado) Flight Telemetry)
1153:University of Texas at Austin (910, 930, Sigma 5)
1114:(RIT) (Sigma 6 academic/administrative computing)
2386:
1812:
1596:Tsuruga Japan (Sigma 5 - Nuclear Core Simulator)
2420:Defunct computer companies of the United States
1590:(Sigma 5 with Honeywell memory mapping upgrade)
1176:(Sigma 5/7 data reduction system at South Base)
1055:, Experimental Particle Physics Group (Sigma 7)
2350:Oral history interview with Paul A. Strassmann
2225:
2223:
2221:
2219:
2217:
1566:Aircraft (Israel) (Sigma 5 - Flight Telemetry)
1188:Washington Metropolitan Area Transit Authority
430:In December 1966 SDS shipped the entirely new
2370:SDS 900 series documentation at bitsavers.org
1299:Naval Nuclear Lab Idaho Falls Idaho (Sigma 5)
397:) with or without paper tape reader and punch
1787:"Computer Structures: Readings and Examples"
1140:(UCLA) (Sigma 7) "The first computer on the
1014:(Sigma 7, Hybrid Simulation Lab, Goleta, CA)
673:
42:Logo of the company during most of the 1970s
2375:Sigma series documentation at bitsavers.org
2214:
2189:
2187:
2185:
2183:
2181:
2179:
2177:
2152:"SDS Resurfaces With Same Name, New Target"
1305:, Cloudcroft, New Mexico (Sigma 2, Sigma 5)
1103:Queens College, City University of New York
1842:
1840:
1838:
1836:
1578:West Chester University (Sigma 9 and X560)
559:and a proprietary network SDS-NET using a
393:(characters per second) Keyboard/printer (
36:
2415:Computer companies disestablished in 1984
2405:American companies disestablished in 1984
2149:
1808:
1806:
1804:
1802:
1418:Cybernetics Research Consultants (Slough)
1357:, Ponca City, Oklahoma (Sigma 7, Sigma 9)
2174:
2110:
1311:, Scottsdale, Arizona (Sigma 5, Sigma 9)
1212:research lab was running a Sigma 5 as a
451:other ways, such as its use of multiple
417:
178:in 1969, but dwindling sales due to the
2380:Tymshare documentation at bitsavers.org
2229:
2019:from the original on September 24, 2014
1833:
1680:
1614:was released, which was developed into
14:
2410:Computer companies established in 1961
2400:American companies established in 1961
2387:
2356:, University of Minnesota, Minneapolis
2162:from the original on September 9, 2023
1799:
1732:from the original on February 15, 2020
1701:from the original on December 17, 2022
1472:(550 - Submarine Power Plant Research)
1380:Known users outside the U.S. include:
1370:Lawrence Livermore National Laboratory
1058:Los Alamos Scientific Laboratory (930)
980:Central Illinois Light Company (CILCO)
958:used 910s in the 1960s to control its
2202:from the original on February 6, 2015
2003:Scientific Data Systems (June 1965).
1882:
1554:American Israeli Paper Mills (Israel)
1391:(Sigma 2 & 3 - Flight Simulation)
1138:University of California, Los Angeles
574:produced by Tat Lam of the Bay Area.
2294:"Technology Profile: Mini-Computers"
2117:. Xlibris Corporation. p. 104.
1442:(Sigma 5 - Braille Printer Research)
1097:Online Computer Library Center, Inc.
856:less expensive but faster 920 (1964)
2425:Defunct computer hardware companies
2193:
2131:from the original on August 7, 2020
2111:McMurran, Marshall William (2008).
1864:from the original on March 27, 2020
1521:Department of Engineering (Sigma 6)
1493:, AKA Ministry of Public Buildings)
1430:Rank Radio International (Plymouth)
1202:(A/D Flight simulation, Dayton, OH)
934:systems. The biggest such user was
518:produced past the prototype stage.
310:In December 1963 SDS announced the
287:The 910 and 920 were joined by the
24:
2430:Defunct computer systems companies
2326:
2310:from the original on July 18, 2023
2274:from the original on July 18, 2023
2055:from the original on July 11, 2020
1889:. Ballinger Pub. Co. p. 192.
1491:National Gas Turbine Establishment
1324:, Arizona (Sigma 5 LINK Simulator)
1276:University of Southern Mississippi
814:
799:However, the UK company's lack of
584:SDS announced a fully operational
332:, which was commercialized in the
330:University of California, Berkeley
25:
2441:
2365:SDS Sigma 7 technical information
2343:
2150:Rosenberg, Marcy (Feb 12, 1979).
2092:from the original on July 9, 2020
1964:The Industrial Reorganization Act
1163:University of Wisconsin–Green Bay
1112:Rochester Institute of Technology
709:10 and 20 MB hard drives or
608:services over SDS-NET or using a
202:
2073:
2006:Reference Manual SDS 92 Computer
1821:from the original on 25 May 2011
1681:Gregory, Nathan (Mar 16, 2018).
1638:
1345:Dallas Power and Light (Sigma 5)
1148:University of Texas at Arlington
1134:(UCI) Computing Center (Sigma 7)
1132:University of California, Irvine
950:. Recognition Equipment Inc. of
2286:
2250:
2143:
2104:
2067:
2031:
1996:
1971:from the original on 2023-08-13
1944:from the original on 2023-08-13
1927:IBM's 360 and Early 370 Systems
1903:from the original on 2022-12-17
1604:
1434:Royal Naval Engineering College
1284:, Seattle, Washington (Sigma 3)
1263:, Burbank, California (Sigma 7)
1221:United States Air Force Academy
1200:Wright-Patterson Air Force Base
501:
413:
251:in their earliest designs, the
2158:. Vol. XIII, no. 7.
1955:
1917:
1876:
1813:Keith G. Calkins (June 1984).
1779:
1744:
1713:
1674:
1364:Los Alamos National Laboratory
925:
521:
162:, and was an early adopter of
13:
1:
1667:
1448:(Sigma 2 - Particle Research)
1296:, Boulder, Colorado (SDS-940)
1184:Warner Computer Systems, Inc.
1023:Grand Valley State University
960:optical character recognition
765:Institute of Legal Executives
600:. The SDS 430 Server offered
377:2048-word basic memory (1.75
150:and Robert Beck, veterans of
142:founded in September 1961 by
1336:, Phoenix, Arizona (Sigma 5)
1330:, Phoenix, Arizona (Sigma 2)
1294:National Bureau of Standards
946:and Modutest Systems, Inc.,
944:Westlake Village, California
498:with an SDS Sigma 7 system.
7:
2339:, Friday, February 24, 1967
1657:Berkeley Timesharing System
1650:
1594:Mitsubishi Heavy Industries
1503:Watsons (Insurance) Redhill
1464:University College Hospital
1118:Stanford Research Institute
998:(CMU) (Sigma 5, now at the
625:Manhattan Beach, California
426:, Seattle, Washington, 2014
374:12-bit word plus parity bit
371:12- and 24-bit instructions
211:, and the "Seven Dwarves",
190:), whose machines were the
61:; 63 years ago
10:
2446:
2039:"Graduate Studies Catalog"
1930:. MIT Press. p. 440.
1767:"SDS 910 Reference Manual"
1515:(Sigma 9 flight simulator)
1500:
1470:Rolls-Royce and Associates
1385:
1340:Tennessee Valley Authority
1206:
996:Carnegie Mellon University
970:
533:BASIC programming language
446:and the rise of the 7-bit
197:
2354:Charles Babbage Institute
1883:Brock, Gerald W. (1975).
1848:"SDS 92 Reference Manual"
1720:Scientific Data Systems.
1394:Link Simulation (Lansing)
1303:Sunspot Solar Observatory
1272:research vessel (Sigma 2)
1210:Youngstown Sheet and Tube
1174:Vandenberg Air Force Base
1082:Michigan State University
1047:Jet Propulsion Laboratory
871:"low end" machine (1965)
674:SDS in the United Kingdom
400:300 cps paper tape reader
351:
121:
96:
77:
55:
47:
35:
27:American computer company
1643:The Xerox CE16 and CF16
1349:Carolina Power and Light
1288:Montana State University
1053:Johns Hopkins University
1029:Grumman Aircraft Company
1025:(Sigma 6, Allendale, MI)
318:, and the IC-based 925.
293:floating point processor
225:Control Data Corporation
152:Packard Bell Corporation
72:Santa Monica, California
2395:Scientific Data Systems
1633:Computer History Museum
1620:Computer History Museum
1278:, Hattiesburg (Sigma 9)
1261:Hughes Aircraft Company
1122:The Mother of All Demos
1108:Robert Plan Corporation
1089:(Sigma 5 and Sigma 7 -
1000:Computer History Museum
598:Westchester, California
403:60 cps paper tape punch
132:Scientific Data Systems
31:Scientific Data Systems
2258:"controller/computers"
1988:: CS1 maint: others (
1458:Charing Cross Hospital
1452:Addenbrooke's Hospital
1334:Arizona Public Service
1282:Pacific Bell Telephone
1071:Marquardt Aircraft Co.
1008:(Sigma 9) Columbus, IN
656:solid-waste management
427:
424:Living Computer Museum
422:An XDS Sigma 9 at the
328:use on the 930 at the
1180:Vanderbilt University
1168:University of Wyoming
1157:University of Vermont
1091:Pioneer Space Project
858:major redesign (1963)
652:value-added resellers
421:
367:. Features included:
180:oil crisis of 1973–74
2333:"Enter Max Palevsky"
2196:"Former Sigma sites"
1588:Dalhousie University
1519:Cambridge University
1446:Liverpool University
1309:Motorola Electronics
1244:, Colorado (Sigma 3)
1065:Marquette University
805:Personal Computer/AT
680:Crawley, West Sussex
614:diskless workstation
579:scientific computing
434:, starting with the
409:Magnetic Tape System
1489:N.G.T.E. Pyestock (
1476:St Thomas' Hospital
1410:Carleton University
1400:Engineering (Epsom)
1290:, Bozeman (Sigma 7)
985:Bucknell University
940:Ann Arbor, Michigan
748:reverse-engineering
740:Visual Display Unit
633:Accounts Receivable
490:was established by
164:integrated circuits
160:silicon transistors
138:), was an American
32:
2230:Kirkpatrick, Jim.
2083:Nautilus Institute
1792:2008-12-26 at the
1772:2011-01-17 at the
1761:2008-12-18 at the
1687:Lulu. p. 85.
1684:The Tym Before ...
1551:Rank Xerox (Milan)
1481:Government Chemist
1440:Warwick University
1355:Conoco Corporation
1328:Salt River Project
1073:, Van Nuys, Calif.
1006:Cummins Engine Co.
974:Andrews University
592:called SDS-NET at
586:local area network
484:hardware interrupt
428:
299:to add two 24-bit
184:Xerox Data Systems
125:Xerox Data Systems
30:
18:Xerox Data Systems
2238:on April 21, 2021
2124:978-1-4363-8107-9
2074:Spin, William A.
1855:www.bitsavers.org
1694:978-1-387-30405-9
1662:SDS 9xx computers
1602:
1601:
1415:Comshare (London)
1404:British Aerospace
1378:
1377:
1120:(SRI) (used for "
1077:McDonnell Douglas
923:
922:
492:Leonard Kleinrock
129:
128:
16:(Redirected from
2437:
2320:
2319:
2317:
2315:
2309:
2298:
2290:
2284:
2283:
2281:
2279:
2273:
2262:
2254:
2248:
2247:
2245:
2243:
2234:. Archived from
2227:
2212:
2211:
2209:
2207:
2194:Calkins, Keith.
2191:
2172:
2171:
2169:
2167:
2147:
2141:
2140:
2138:
2136:
2108:
2102:
2101:
2099:
2097:
2091:
2080:
2071:
2065:
2064:
2062:
2060:
2054:
2043:
2035:
2029:
2028:
2026:
2024:
2018:
2011:
2000:
1994:
1993:
1987:
1979:
1977:
1976:
1959:
1953:
1952:
1950:
1949:
1921:
1915:
1914:
1909:
1908:
1880:
1874:
1873:
1871:
1869:
1863:
1852:
1844:
1831:
1830:
1828:
1826:
1810:
1797:
1783:
1777:
1756:"SDS 900 Series"
1748:
1742:
1741:
1739:
1737:
1722:"SDS 900 series"
1717:
1711:
1710:
1708:
1706:
1678:
1383:
1382:
968:
967:
948:Phoenix, Arizona
819:
818:
795:
794:
790:
787:
734:
733:
729:
726:
700:
699:
695:
692:
637:Accounts Payable
621:Jacquard Systems
475:capability, the
438:Sigma 2 and the
342:circuit-switched
233:General Electric
192:Xerox 500 series
140:computer company
113:
111:
69:
67:
62:
40:
33:
29:
21:
2445:
2444:
2440:
2439:
2438:
2436:
2435:
2434:
2385:
2384:
2346:
2329:
2327:Further reading
2324:
2323:
2313:
2311:
2307:
2296:
2292:
2291:
2287:
2277:
2275:
2271:
2260:
2256:
2255:
2251:
2241:
2239:
2232:"The Sigma Era"
2228:
2215:
2205:
2203:
2192:
2175:
2165:
2163:
2148:
2144:
2134:
2132:
2125:
2109:
2105:
2095:
2093:
2089:
2078:
2072:
2068:
2058:
2056:
2052:
2041:
2037:
2036:
2032:
2022:
2020:
2016:
2009:
2001:
1997:
1981:
1980:
1974:
1972:
1961:
1960:
1956:
1947:
1945:
1938:
1922:
1918:
1906:
1904:
1897:
1881:
1877:
1867:
1865:
1861:
1850:
1846:
1845:
1834:
1824:
1822:
1811:
1800:
1794:Wayback Machine
1784:
1780:
1774:Wayback Machine
1763:Wayback Machine
1749:
1745:
1735:
1733:
1718:
1714:
1704:
1702:
1695:
1679:
1675:
1670:
1653:
1641:
1607:
1389:British Airways
1315:United Airlines
1269:Glomar Explorer
1230:Martin Marietta
1214:Hybrid computer
1150:(UTA) (Sigma 7)
1041:Hughes Aircraft
928:
918:
916:
911:Xerox Sigma 8/9
909:
905:
893:
891:
887:CE16 & CF16
886:
882:
859:
857:
855:
853:
851:
844:
840:
836:
832:
828:
817:
815:Computer models
792:
788:
785:
783:
731:
727:
724:
722:
703:hard disk drive
697:
693:
690:
688:
676:
606:printer sharing
524:
504:
463:French company
455:rather than an
416:
354:
276:, developed by
205:
200:
117:
109:
107:
92:
65:
63:
60:
43:
28:
23:
22:
15:
12:
11:
5:
2443:
2433:
2432:
2427:
2422:
2417:
2412:
2407:
2402:
2397:
2383:
2382:
2377:
2372:
2367:
2362:
2357:
2345:
2344:External links
2342:
2341:
2340:
2328:
2325:
2322:
2321:
2285:
2249:
2213:
2173:
2142:
2123:
2103:
2066:
2030:
1995:
1954:
1936:
1916:
1895:
1875:
1832:
1798:
1785:Bell, Gordon,
1778:
1752:Atlas computer
1743:
1712:
1693:
1672:
1671:
1669:
1666:
1665:
1664:
1659:
1652:
1649:
1640:
1637:
1606:
1603:
1600:
1599:
1598:
1597:
1591:
1585:
1579:
1576:
1570:
1567:
1561:
1555:
1552:
1549:
1543:
1537:
1531:
1525:
1522:
1516:
1510:
1504:
1499:
1498:
1497:
1494:
1487:
1482:
1479:
1473:
1467:
1461:
1455:
1449:
1443:
1437:
1431:
1428:
1422:
1419:
1416:
1413:
1407:
1401:
1395:
1392:
1376:
1375:
1374:
1373:
1367:
1361:
1358:
1352:
1346:
1343:
1337:
1331:
1325:
1318:
1312:
1306:
1300:
1297:
1291:
1285:
1279:
1273:
1266:Global Marine
1264:
1258:
1255:
1252:
1245:
1236:
1233:
1227:
1224:
1217:
1205:
1204:
1203:
1197:
1191:
1185:
1182:
1177:
1171:
1165:
1160:
1154:
1151:
1145:
1135:
1129:
1128:(NLS) in 1968)
1126:oN-Line System
1115:
1109:
1106:
1100:
1094:
1084:
1079:
1074:
1068:
1062:
1059:
1056:
1050:
1044:
1038:
1032:
1026:
1020:
1015:
1009:
1003:
993:
987:
982:
977:
927:
924:
921:
920:
913:
900:
899:32-bit systems
896:
895:
888:
877:
876:16-bit systems
873:
872:
869:
866:
862:
861:
848:
823:
822:24-bit systems
816:
813:
796:-inch drives.
675:
672:
629:General Ledger
549:Marina del Rey
523:
520:
503:
500:
473:dual-processor
469:virtual memory
444:IBM System/360
415:
412:
411:
410:
404:
401:
398:
383:
382:
375:
372:
353:
350:
204:
203:Early machines
201:
199:
196:
127:
126:
123:
119:
118:
116:
115:
104:
100:
98:
94:
93:
91:
90:
87:
81:
79:
75:
74:
57:
53:
52:
49:
45:
44:
41:
26:
9:
6:
4:
3:
2:
2442:
2431:
2428:
2426:
2423:
2421:
2418:
2416:
2413:
2411:
2408:
2406:
2403:
2401:
2398:
2396:
2393:
2392:
2390:
2381:
2378:
2376:
2373:
2371:
2368:
2366:
2363:
2361:
2358:
2355:
2351:
2348:
2347:
2338:
2337:Time Magazine
2334:
2331:
2330:
2306:
2302:
2295:
2289:
2270:
2266:
2259:
2253:
2237:
2233:
2226:
2224:
2222:
2220:
2218:
2201:
2197:
2190:
2188:
2186:
2184:
2182:
2180:
2178:
2161:
2157:
2156:Computerworld
2153:
2146:
2130:
2126:
2120:
2116:
2115:
2107:
2088:
2084:
2077:
2070:
2051:
2047:
2040:
2034:
2015:
2008:
2007:
1999:
1991:
1985:
1970:
1966:
1965:
1958:
1943:
1939:
1937:9780262161237
1933:
1929:
1928:
1920:
1913:
1902:
1898:
1896:9780884102618
1892:
1888:
1887:
1879:
1860:
1856:
1849:
1843:
1841:
1839:
1837:
1820:
1816:
1809:
1807:
1805:
1803:
1795:
1791:
1788:
1782:
1775:
1771:
1768:
1764:
1760:
1757:
1753:
1747:
1731:
1727:
1723:
1716:
1700:
1696:
1690:
1686:
1685:
1677:
1673:
1663:
1660:
1658:
1655:
1654:
1648:
1646:
1645:minicomputers
1639:CE16 and CF16
1636:
1634:
1629:
1626:
1621:
1617:
1613:
1595:
1592:
1589:
1586:
1583:
1580:
1577:
1574:
1571:
1568:
1565:
1562:
1559:
1556:
1553:
1550:
1547:
1544:
1541:
1538:
1535:
1532:
1529:
1526:
1523:
1520:
1517:
1514:
1511:
1508:
1505:
1502:
1501:
1495:
1492:
1488:
1486:
1483:
1480:
1477:
1474:
1471:
1468:
1465:
1462:
1459:
1456:
1453:
1450:
1447:
1444:
1441:
1438:
1435:
1432:
1429:
1426:
1423:
1420:
1417:
1414:
1411:
1408:
1405:
1402:
1399:
1396:
1393:
1390:
1387:
1386:
1384:
1381:
1371:
1368:
1365:
1362:
1359:
1356:
1353:
1350:
1347:
1344:
1341:
1338:
1335:
1332:
1329:
1326:
1323:
1319:
1316:
1313:
1310:
1307:
1304:
1301:
1298:
1295:
1292:
1289:
1286:
1283:
1280:
1277:
1274:
1271:
1270:
1265:
1262:
1259:
1256:
1253:
1250:
1246:
1243:
1240:
1237:
1234:
1231:
1228:
1225:
1222:
1218:
1215:
1211:
1208:
1207:
1201:
1198:
1195:
1192:
1189:
1186:
1183:
1181:
1178:
1175:
1172:
1169:
1166:
1164:
1161:
1158:
1155:
1152:
1149:
1146:
1143:
1139:
1136:
1133:
1130:
1127:
1123:
1119:
1116:
1113:
1110:
1107:
1104:
1101:
1098:
1095:
1092:
1088:
1085:
1083:
1080:
1078:
1075:
1072:
1069:
1066:
1063:
1060:
1057:
1054:
1051:
1048:
1045:
1042:
1039:
1036:
1033:
1030:
1027:
1024:
1021:
1019:
1018:Eastman Kodak
1016:
1013:
1010:
1007:
1004:
1001:
997:
994:
991:
988:
986:
983:
981:
978:
975:
972:
971:
969:
966:
963:
961:
957:
953:
949:
945:
941:
937:
933:
914:
912:
908:
907:SDS Sigma 6/7
904:
901:
898:
897:
889:
885:
881:
878:
875:
874:
870:
867:
865:12-bit system
864:
863:
849:
847:
843:
839:
835:
831:
827:
824:
821:
820:
812:
809:
806:
802:
797:
781:
776:
774:
770:
766:
762:
761:Poole, Dorset
757:
754:
749:
743:
741:
736:
720:
716:
712:
708:
705:bay and used
704:
684:
681:
671:
669:
665:
661:
657:
653:
649:
644:
642:
638:
634:
630:
626:
622:
617:
615:
611:
607:
603:
599:
595:
591:
587:
582:
580:
575:
573:
569:
566:
562:
558:
554:
550:
546:
542:
538:
534:
530:
519:
515:
513:
509:
508:United States
499:
497:
493:
489:
485:
480:
478:
474:
470:
466:
460:
458:
454:
449:
445:
441:
437:
433:
425:
420:
408:
405:
402:
399:
396:
392:
388:
387:
386:
380:
376:
373:
370:
369:
368:
366:
361:
359:
349:
347:
343:
339:
335:
331:
327:
323:
322:Project Genie
319:
317:
313:
308:
306:
302:
298:
294:
290:
285:
283:
282:magnetic tape
279:
275:
272:
267:
265:
261:
257:
254:
250:
246:
242:
238:
234:
230:
226:
222:
218:
214:
210:
195:
193:
189:
185:
181:
177:
173:
169:
165:
161:
157:
153:
149:
145:
141:
137:
133:
124:
120:
114:(UK division)
105:
102:
101:
99:
95:
88:
86:
83:
82:
80:
76:
73:
58:
54:
50:
46:
39:
34:
19:
2312:. Retrieved
2300:
2288:
2276:. Retrieved
2264:
2252:
2240:. Retrieved
2236:the original
2204:. Retrieved
2164:. Retrieved
2155:
2145:
2133:. Retrieved
2113:
2106:
2094:. Retrieved
2082:
2069:
2057:. Retrieved
2046:UW-Green bay
2045:
2033:
2021:. Retrieved
2005:
1998:
1973:. Retrieved
1963:
1957:
1946:. Retrieved
1926:
1919:
1911:
1905:. Retrieved
1885:
1878:
1866:. Retrieved
1854:
1823:. Retrieved
1781:
1746:
1734:. Retrieved
1725:
1715:
1703:. Retrieved
1683:
1676:
1642:
1630:
1608:
1605:SDS software
1558:Israeli Navy
1379:
1267:
1035:Hope College
964:
932:time-sharing
929:
810:
798:
777:
758:
744:
737:
685:
677:
647:
645:
618:
588:(LAN)-based
583:
576:
572:transceivers
545:Santa Monica
525:
516:
505:
502:Xerox models
481:
461:
432:Sigma series
429:
414:Sigma series
384:
365:Sigma series
362:
357:
355:
326:time-sharing
320:
309:
297:microseconds
286:
268:
241:time-sharing
206:
187:
183:
144:Max Palevsky
135:
131:
130:
85:Max Palevsky
2301:Modern Data
1625:UC Berkeley
1513:RAE Bedford
1454:(Cambridge)
1242:Buckley AFB
1170:(Sigma 5/7)
926:Known users
903:SDS Sigma 5
884:SDS Sigma 3
880:SDS Sigma 2
590:file server
541:floppy disk
529:6502A-based
522:A new start
457:accumulator
249:transistors
170:during the
148:Arthur Rock
89:Robert Beck
2389:Categories
2265:Datamation
2206:August 29,
1975:2020-12-04
1948:2020-12-04
1907:2020-12-04
1668:References
1573:Vattenfall
1425:Rank Xerox
1249:Nellis AFB
962:machines.
172:Space Race
1984:cite book
1868:March 16,
1726:yumpu.com
1548:(Algeria)
1546:Sonatrach
1528:Aeritalia
1507:A&AEE
1436:(Manadon)
1412:(Sigma 9)
1398:WS Atkins
1372:(Sigma 7)
1366:(Sigma 2)
1351:(Sigma 5)
1342:(Sigma 5)
1223:(Sigma 5)
1194:Whirlpool
1159:(Sigma 7)
1124:" on the
1067:(Sigma 9)
976:(Sigma 7)
537:Microsoft
512:Honeywell
453:registers
264:germanium
229:Honeywell
213:Burroughs
122:Successor
51:Computers
2314:July 18,
2305:Archived
2278:July 18,
2269:Archived
2242:July 17,
2200:Archived
2160:Archived
2129:Archived
2087:Archived
2050:Archived
2014:Archived
1969:Archived
1942:Archived
1901:Archived
1859:Archived
1819:Archived
1790:Archived
1770:Archived
1759:Archived
1730:Archived
1699:Archived
1651:See also
1496:J. Sefel
1478:(London)
1466:(London)
1460:(London)
1427:(Denham)
1322:Luke AFB
990:Caltrans
938:Inc. of
936:Comshare
834:SDS 9300
753:firmware
568:Ethernet
395:teletype
338:Tymshare
301:integers
289:SDS 9300
274:compiler
78:Founders
48:Industry
2096:July 9,
2059:July 9,
2023:Sep 20,
1736:Feb 15,
1705:Feb 15,
1190:(WMATA)
1142:ARPANET
919:(1971)
846:SDS 940
842:SDS 930
838:SDS 925
830:SDS 920
826:SDS 910
801:capital
791:⁄
730:⁄
719:Adaptec
711:SyQuest
707:Seagate
696:⁄
668:Lloyd's
660:Dorking
641:Payroll
488:ARPANET
477:Iris 80
334:SDS 940
312:SDS 930
278:Digitek
271:FORTRAN
260:SDS 920
256:SDS 910
247:-based
245:silicon
198:History
108: (
97:Defunct
64: (
56:Founded
2166:Nov 6,
2135:Jul 9,
2121:
1934:
1893:
1825:15 May
1691:
952:Dallas
917:(1966)
915:(1967)
892:(1969)
890:(1966)
868:SDS 92
852:
773:MS-DOS
769:IBM PC
701:-inch
664:Surrey
639:, and
594:COMDEX
565:Mbit/s
440:32-bit
436:16-bit
407:MAGPAK
358:SDS 92
352:SDS 92
316:SDS 92
305:kWords
253:24-bit
235:, and
217:UNIVAC
156:Bendix
2308:(PDF)
2297:(PDF)
2272:(PDF)
2261:(PDF)
2090:(PDF)
2079:(PDF)
2053:(PDF)
2042:(PDF)
2017:(PDF)
2010:(PDF)
1862:(PDF)
1851:(PDF)
1582:UTLAS
1560:(560)
1320:USAF
1247:USAF
1012:Delco
956:Texas
894:1969
610:modem
561:Z8530
557:USART
535:from
448:ASCII
176:Xerox
2316:2023
2280:2023
2244:2023
2208:2013
2168:2015
2137:2020
2119:ISBN
2098:2020
2061:2020
2025:2014
1990:link
1932:ISBN
1891:ISBN
1870:2019
1827:2011
1738:2020
1707:2020
1689:ISBN
1616:CP-V
1485:GCHQ
1239:USAF
1219:The
1087:NASA
780:SCSI
715:SCSI
604:and
602:file
570:and
553:6551
547:and
496:UCLA
471:and
379:ÎĽsec
356:The
258:and
168:NASA
154:and
110:1984
106:1984
103:1975
66:1961
59:1961
1612:UTS
1564:IAF
1540:ICI
1534:MBB
775:.)
648:TTY
555:-A
494:at
465:CII
391:cps
389:10
346:I/O
340:'s
237:RCA
221:NCR
215:,
209:IBM
188:XDS
136:SDS
70:in
2391::
2352:,
2335:,
2299:.
2263:.
2216:^
2198:.
2176:^
2154:.
2127:.
2085:.
2081:.
2048:.
2044:.
2012:.
1986:}}
1982:{{
1940:.
1910:.
1899:.
1857:.
1853:.
1835:^
1817:.
1801:^
1728:.
1724:.
1697:.
954:,
662:,
635:,
631:,
623:,
231:,
227:,
223:,
219:,
194:.
146:,
2318:.
2282:.
2246:.
2210:.
2170:.
2139:.
2100:.
2063:.
2027:.
1992:)
1978:.
1951:.
1872:.
1829:.
1740:.
1709:.
1144:"
1093:)
1002:)
793:4
789:1
786:+
784:5
732:4
728:1
725:+
723:5
698:4
694:1
691:+
689:5
186:(
134:(
112:)
68:)
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
