Editing Microprocessor (section)

===First projects===
These projects delivered a microprocessor at about the same time: [[Garrett AiResearch]]'s [[Central Air Data Computer]] (CADC) (1970), [[Texas Instruments]]' TMS 1802NC (September 1971) and [[Intel]]'s [[4004]] (November 1971, based on an earlier 1969 [[Busicom]] design). Arguably, [[Four-Phase Systems AL1]] microprocessor was also delivered in 1969.

====Four-Phase Systems AL1 (1969)====
The [[Four-Phase Systems AL1]] was an 8-bit [[bit slice]] chip containing eight registers and an ALU.<ref>{{cite book | page=121 | chapter=When is a Microprocessor not a Microprocessor? The Industrial Construction of Semiconductor Innovation | author=Basset, Ross | title=Exposing Electronics | editor=Finn, Bernard | publisher=Michigan State University Press | year=2003 | isbn=978-0-87013-658-0 | chapter-url=https://books.google.com/books?id=rsRJTiu1h9MC | url-status=live | archive-url=https://web.archive.org/web/20140330235547/http://books.google.com/books?id=rsRJTiu1h9MC | archive-date=2014-03-30 }}</ref><!-- UK ed. same page scheme--> It was designed by [[Lee Boysel]] in 1969.<ref>{{cite web | url=http://www.computerhistory.org/semiconductor/timeline/1971-MPU.html | publisher=Computer History Museum | website=The Silicon Engine | title=1971 - Microprocessor Integrates CPU Function onto a Single Chip | access-date=2010-07-25 | url-status=live | archive-url=https://web.archive.org/web/20100608102128/http://www.computerhistory.org/semiconductor/timeline/1971-MPU.html | archive-date=2010-06-08 }}</ref><ref>{{cite web | url=http://home.comcast.net/~gordonepeterson2/schaller_dissertation_2004.pdf | title=Technological Innovation in the Semiconductor Industry: A Case Study of the International Technology Roadmap for Semiconductors | author=Shaller, Robert R. | date=15 April 2004 | publisher=George Mason University | access-date=2010-07-25 | archive-url=https://web.archive.org/web/20061219012629/http://home.comcast.net/~gordonepeterson2/schaller_dissertation_2004.pdf | archive-date=2006-12-19 | url-status=live }}</ref><ref>{{cite web | url=http://www-sul.stanford.edu/depts/hasrg/histsci/silicongenesis/moore-ntb.html | title=Interview with Gordon E. Moore | date=3 March 1995 | location=Los Altos Hills, California | author=RW | publisher=Stanford University | website=[[LAIR]] History of Science and Technology Collections | url-status=live | archive-url=https://web.archive.org/web/20120204045916/http://www-sul.stanford.edu/depts/hasrg/histsci/silicongenesis/moore-ntb.html | archive-date=4 February 2012 }}</ref> At the time, it formed part of a nine-chip, 24-bit CPU with three AL1s. It was later called a microprocessor when, in response to 1990s litigation by [[Texas Instruments]], Boysel constructed a demonstration system where a single AL1 with a 1969 datestamp formed part of a courtroom demonstration computer system, together with RAM, ROM, and an input-output device.<ref>Bassett 2003. pp. 115, 122.</ref> The AL1 wasn't sold individually, but was part of the System IV/70 announced in September 1970 and first delivered in February 1972.<ref name=":0">https://bitsavers.trailing-edge.com/pdf/datapro/datapro_reports_70s-90s/Four_Phase/M11-435-10_7908_Four-Phase_System_IV.pdf {{Bare URL PDF|date=May 2025}}</ref>

====Garrett AiResearch CADC (1970)====
{{Primary sources|section|date=March 2010}}
{{Further|F-14 CADC}}

In 1968, [[Garrett AiResearch]] (who employed designers [[Ray Holt (computer scientist)|Ray Holt]] and Steve Geller) was invited to produce a digital computer to compete with [[electromechanical]] systems then under development for the main flight control computer in the [[US Navy]]'s new [[F-14 Tomcat]] fighter. The design was complete by 1970, and used a [[MOSFET|MOS]]-based chipset as the core CPU. The design was significantly (approximately 20 times) smaller and much more reliable than the mechanical systems it competed against and was used in all of the early Tomcat models. This system contained "a 20-bit, [[Pipeline (computing)|pipelined]], [[Parallel computing|parallel]] [[multiprocessor|multi-microprocessor]]". The Navy refused to allow publication of the design until 1997. Released in 1998, the documentation on the [[Central Air Data Computer|CADC]], and the [[MP944]] chipset, are well known. Ray Holt's autobiographical story of this design and development is presented in the book: The Accidental Engineer.<ref>{{Cite web|url=https://firstmicroprocessor.com/|archiveurl=https://web.archive.org/web/20140106143912/http://www.firstmicroprocessor.com/|url-status=dead|title=First Microprocessor|archivedate=January 6, 2014|website=First Microprocessor &#124; 50th Anniversary of the Microprocessor 2020}}</ref><ref>{{cite web | title=World's First Microprocessor Chip Set | last=Holt | first=Ray M. | url=http://www.firstmicroprocessor.com | publisher=Ray M. Holt website | archive-date=January 6, 2014 | access-date=2010-07-25 | url-status=live | archive-url=https://web.archive.org/web/20140106143912/http://www.firstmicroprocessor.com/ }}</ref>
Ray Holt graduated from [[California State Polytechnic University, Pomona]] in 1968, and began his computer design career with the CADC.<ref>{{Cite magazine |last=Fallon |first=Sarah |title=The Secret History of the First Microprocessor, the F-14, and Me |url=https://www.wired.com/story/secret-history-of-the-first-microprocessor-f-14/ |access-date=2024-01-21 |magazine=Wired |language=en-US |issn=1059-1028 |archive-date=18 January 2024 |archive-url=https://web.archive.org/web/20240118132936/https://www.wired.com/story/secret-history-of-the-first-microprocessor-f-14/ |url-status=live }}</ref> From its inception, it was shrouded in secrecy until 1998 when at Holt's request, the US Navy allowed the documents into the public domain. Holt has claimed that no one has compared this microprocessor with those that came later.<ref>{{cite speech | title=Lecture: Microprocessor Design and Development for the US Navy F14 FighterJet | last=Holt | first=Ray | date=27 September 2001 | location=Room 8220, Wean Hall, Carnegie Mellon University, Pittsburgh, PA, US | url=http://www.pdl.cmu.edu/SDI/2001/092701.html | access-date=2010-07-25 | url-status=live | archive-url=https://web.archive.org/web/20111001020654/http://www.pdl.cmu.edu/SDI/2001/092701.html | archive-date=1 October 2011 }}</ref> According to Parab et al. (2007), {{Blockquote|text=The scientific papers and literature published around 1971 reveal that the MP944 digital processor used for the F-14 Tomcat aircraft of the US Navy qualifies as the first microprocessor. Although interesting, it was not a single-chip processor, as was not the Intel 4004{{snd}}they both were more like a set of parallel building blocks you could use to make a general-purpose form. It contains a CPU, [[RAM]], [[ROM]], and two other support chips like the Intel 4004. It was made from the same [[PMOS logic|P-channel]] technology, operated at [[military specifications]] and had larger chips{{snd}}an excellent computer engineering design by any standards. Its design indicates a major advance over Intel, and two year earlier. It actually worked and was flying in the F-14 when the Intel 4004 was announced. It indicates that today's industry theme of converging [[Digital signal processor|DSP]]-[[microcontroller]] architectures was started in 1971.<ref>{{cite book | title=Exploring C for Microcontrollers: A Hands on Approach | last1=Parab | first1=Jivan S. | last2=Shelake | first2=Vinod G. | last3=Kamat | first3=Rajanish K. | last4=Naik | first4=Gourish M. | publisher=Springer | page=4 | year=2007 | isbn=978-1-4020-6067-0 | url=http://ee.sharif.edu/~sakhtar3/books/Exploring%20C%20for%20Microcontrollers.pdf | access-date=2010-07-25 | url-status=live | archive-url=https://web.archive.org/web/20110720043756/http://ee.sharif.edu/~sakhtar3/books/Exploring%20C%20for%20Microcontrollers.pdf | archive-date=2011-07-20 }}</ref>}} This convergence of DSP and microcontroller architectures is known as a [[digital signal controller]].<ref>{{cite book|editor=Yovits, M. C.|author1=Dyer, S. A.|author2=Harms, B. K.|chapter=Digital Signal Processing|title=Advances in Computers|year=1993|volume=37|pages=104–107|publisher=Academic Press|doi=10.1016/S0065-2458(08)60403-9|isbn=9780120121373|chapter-url=https://books.google.com/books?id=vL-bB7GALAwC&pg=PA104|url-status=live|archive-url=https://web.archive.org/web/20161229031814/https://books.google.com/books?id=vL-bB7GALAwC&pg=PA104|archive-date=2016-12-29}}</ref>

====Gilbert Hyatt (1970) ====
In 1990, American engineer Gilbert Hyatt was awarded U.S. Patent No. 4,942,516,<ref>{{Cite patent|country=US|number=4942516|title=Single chip integrated circuit computer architecture|gdate=1990-07-17|invent1=Hyatt|inventor1-first=Gilbert P|url=https://patents.google.com/patent/US4942516A}} {{Webarchive|url=https://web.archive.org/web/20120525061939/http://www.google.com/patents/about?id=cNcbAAAAEBAJ |date=25 May 2012 }}</ref> which was based on a 16-bit serial computer he built at his [[Northridge, California]], home in 1969 from boards of bipolar chips after quitting his job at [[Teledyne]] in 1968;<ref name = "IEEE" /><ref name= "LAT" /> though the patent had been submitted in December 1970 and prior to [[Texas Instruments]]' filings for the TMX 1795 and TMS 0100, Hyatt's invention was never manufactured.<ref name ="LAT"/><ref>{{cite news | url=https://www.nytimes.com/1996/06/20/business/for-texas-instruments-some-bragging-rights.html | title=For Texas Instruments, Some Bragging Rights | newspaper=The New York Times | date=20 June 1996 | last1=Markoff | first1=John | access-date=4 October 2022 | archive-date=28 September 2022 | archive-url=https://web.archive.org/web/20220928210935/https://www.nytimes.com/1996/06/20/business/for-texas-instruments-some-bragging-rights.html | url-status=live }}</ref><ref>{{cite web | url=https://www.pcmag.com/news/the-birth-of-the-microprocessor | title=The Birth of the Microprocessor | date=16 December 2014 | access-date=4 October 2022 | archive-date=4 October 2022 | archive-url=https://web.archive.org/web/20221004020435/https://www.pcmag.com/news/the-birth-of-the-microprocessor | url-status=live }}</ref> This nonetheless led to claims that Hyatt was the inventor of the microprocessor and the payment of substantial royalties through a [[Philips N.V.]] subsidiary,<ref>{{cite web | url=https://www.latimes.com/archives/la-xpm-1991-11-07-fi-1581-story.html | title=Microprocessor Patent Holder Signs Contract : Invention: La Palma inventor signs with Dutch electronics giant, the first company to accord validity to his patent | website=[[Los Angeles Times]] | date=7 November 1991 | access-date=4 October 2022 | archive-date=4 October 2022 | archive-url=https://web.archive.org/web/20221004023903/https://www.latimes.com/archives/la-xpm-1991-11-07-fi-1581-story.html | url-status=live }}</ref> until Texas Instruments prevailed in a complex legal battle in 1996, when the U.S. Patent Office overturned key parts of the patent, while allowing Hyatt to keep it.<ref name = "IEEE" /><ref>{{cite web | url=https://lasvegassun.com/news/2014/dec/21/inventors-fight-recognition-ongoing-not-all-consum/ | title=Inventor's fight for recognition ongoing but not all-consuming - Las Vegas Sun Newspaper | date=21 December 2014 | access-date=4 October 2022 | archive-date=20 October 2022 | archive-url=https://web.archive.org/web/20221020013849/https://lasvegassun.com/news/2014/dec/21/inventors-fight-recognition-ongoing-not-all-consum/ | url-status=live }}</ref> Hyatt said in a 1990 ''Los Angeles Times'' article that his invention would have been created had his prospective investors backed him, and that the venture investors leaked details of his chip to the industry, though he did not elaborate with evidence to support this claim.<ref name ="LAT">{{cite web | url=https://www.latimes.com/archives/la-xpm-1990-10-21-fi-4400-story.html | title=Chip Designer's 20-Year Quest : Computers: Gilbert Hyatt's solitary battle to patent the microprocessor appears to have paid off, if it can withstand legal challenges. Here's his story | website=[[Los Angeles Times]] | date=21 October 1990 | access-date=4 October 2022 | archive-date=4 October 2022 | archive-url=https://web.archive.org/web/20221004020434/https://www.latimes.com/archives/la-xpm-1990-10-21-fi-4400-story.html | url-status=live }}</ref> In the same article, ''The Chip'' author [[T.R. Reid]] was quoted as saying that historians may ultimately place Hyatt as a co-inventor of the microprocessor, in the way that Intel's Noyce and TI's Kilby share credit for the invention of the chip in 1958: "Kilby got the idea first, but Noyce made it practical. The legal ruling finally favored Noyce, but they are considered co-inventors. The same could happen here."<ref name = "LAT"/> Hyatt would go on to fight a decades-long legal battle with the state of California over alleged unpaid taxes on his patent's windfall after 1990, which would culminate in a landmark Supreme Court case addressing states' [[sovereign immunity]] in ''[[Franchise Tax Board of California v. Hyatt (2019)]]''.

====Texas Instruments TMX 1795 (1970–1971)====
Texas Instruments developed in 1970&ndash;1971 a one-chip CPU replacement for the [[Datapoint 2200]] terminal, the TMX 1795 (later TMC 1795). Like Intel's later [[8008]], it was rejected by customer Datapoint. According to Gary Boone, the TMX 1795 never reached production. Still it reached a prototype state at 1971 February 24.<ref name="righto_com">{{cite web | url=https://www.righto.com/2015/05/the-texas-instruments-tmx-1795-first.html | title=The Texas Instruments TMX 1795: The (Almost) first, forgotten microprocessor }}</ref> Since it was built to the same specification, its instruction set was very similar to the Intel 8008.<ref name="genie">{{cite book |first1=Frederick |last1=Seitz |first2=Norman G. |last2=Einspruch |chapter=19. The 1970s and the Microprocessor § Texas Instruments |title=Electronic Genie: The Tangled History of Silicon |publisher=University of Illinois Press |date=1998 |isbn=0252023838 |pages=228–9 |chapter-url=https://books.google.com/books?id=IT90cDPh54wC&pg=PA229 |access-date=14 August 2022 |archive-date=19 February 2023 |archive-url=https://web.archive.org/web/20230219195307/https://books.google.com/books?id=IT90cDPh54wC&pg=PA229 |url-status=live }}</ref><ref name="shirriff">{{cite journal |first=Ken |last=Shirriff |title=The Surprising Story of the First Microprocessors |journal=IEEE Spectrum |volume=53 |issue=9 |pages=48–54 |date=2016 |doi=10.1109/MSPEC.2016.7551353 |s2cid=32003640 |url=https://ieeexplore.ieee.org/document/7551353 |access-date=14 August 2022 |archive-date=14 August 2022 |archive-url=https://web.archive.org/web/20220814014410/https://ieeexplore.ieee.org/document/7551353 |url-status=live |url-access=subscription }}</ref>

====Texas Instruments TMS 1802NC (1971)====
The TMS1802NC, announced September 17, 1971, was the first microcontroller and at launch implemented a four-function calculator. The TMS1802NC, despite its designation, was not part of the [[TMS 1000]] series; it was later redesignated as part of the TMS 0100 series, which was used in the TI Datamath calculator. It was marketed as a calculator-on-a-chip and also "fully programmable", but this programming had to done during manufacturing. Its chip integrated a CPU with an 11-bit instruction word, 3520 bits (320 instructions) of ROM and 182 bits of RAM.<ref name="genie" /><ref>U.S. Patent no. 4,074,351 (TMS1802NC.)</ref><ref name="shirriff" /><ref>[https://web.archive.org/web/20060218021723/http://www.ti.com/corp/docs/company/history/calcchip.shtml "STANDARD CALCULATOR ON A CHIP ANNOUNCED BY TEXAS INSTRUMENTS"], press release. TI, Sep. 19, 1971.  Originally on ti.com but now archived at archive.org.</ref>

====Pico/General Instrument (1971)====
[[File:GI250 PICO1 die photo.jpg|thumb|upright=1.2|The PICO1/GI250 chip introduced in 1971: It was designed by Pico Electronics (Glenrothes, Scotland) and manufactured by General Instrument of Hicksville NY.]]

In 1971, Pico Electronics<ref>{{cite web | title=Microprocessor History: Foundations in Glenrothes, Scotland | last=McGonigal | first=James | date=20 September 2006 | url=http://www.spingal.plus.com/micro | website=McGonigal personal website | access-date=2009-12-23 | url-status=dead | archive-url=https://web.archive.org/web/20110720142104/http://www.spingal.plus.com/micro/ | archive-date=20 July 2011 }}</ref> and [[General Instrument]] (GI) introduced their first collaboration in ICs, a complete single-chip calculator IC for the Monroe/[[Litton Industries|Litton]] Royal Digital III calculator. This chip could also arguably lay claim to be one of the first microprocessors or microcontrollers having [[ROM]], [[RAM]] and a [[RISC]] instruction set on-chip. The layout for the four layers of the [[PMOS logic|PMOS]] process was hand drawn at x500 scale on mylar film, a significant task at the time given the complexity of the chip.

Pico was a spinout by five GI design engineers whose vision was to create single-chip calculator ICs. They had significant previous design experience on multiple calculator chipsets with both GI and [[Elliott Automation|Marconi-Elliott]].<ref>{{cite web | title=ANITA at its Zenith | website=Bell Punch Company and the ANITA calculators | first=Nigel | last=Tout | url=http://anita-calculators.info/html/anita_at_its_zenith.html | access-date=2010-07-25 | url-status=live | archive-url=https://web.archive.org/web/20100811034328/http://anita-calculators.info/html/anita_at_its_zenith.html | archive-date=2010-08-11 }}</ref> The key team members had originally been tasked by [[Elliott Automation]] to create an 8-bit computer in MOS and had helped establish a MOS Research Laboratory in [[Glenrothes]], Scotland in 1967.

Calculators were becoming the largest single market for semiconductors so Pico and GI went on to have significant success in this burgeoning market. GI continued to innovate in microprocessors and microcontrollers with products including the CP1600, IOB1680 and PIC1650.<ref>16 Bit Microprocessor Handbook by Gerry Kane, Adam Osborne {{ISBN|0-07-931043-5}} (0-07-931043-5)</ref> In 1987, the GI Microelectronics business was spun out into the [[Microchip Technology|Microchip]] [[PIC microcontroller]] business.

====Intel 4004 (1971) ====
{{Main|Intel 4004}}
[[File:C4004 (Intel).jpg|thumb|Intel's first microprocessor, the [[4004]], with cover removed (left) and as actually used (right)]]
[[File:Intel_4004_ad.jpg|thumb|Intel advertisement in [[Electronic News]] magazine from 1971 emphasizing the 4004's affordability, compactness, ease of programming, and flexibility.]]
The [[Intel 4004]] is often (falsely) regarded as the first true microprocessor built on a single chip,<ref>{{cite web | title=The Microcomputer Revolution | first=Pamela E. | last=Mack | date=30 November 2005 | url=http://www.clemson.edu/caah/history/FacultyPages/PamMack/lec122/micro.htm | access-date=2009-12-23 | url-status=live | archive-url=https://web.archive.org/web/20100114160413/http://www.clemson.edu/caah/history/FacultyPages/PamMack/lec122/micro.htm | archive-date=14 January 2010 }}</ref><ref>{{cite web | title=History in the Computing Curriculum | url=http://www.hofstra.edu/pdf/CompHist_9812tla6.PDF | access-date=2009-12-23 | url-status=dead | archive-url=https://web.archive.org/web/20110719211222/http://www.hofstra.edu/pdf/CompHist_9812tla6.PDF | archive-date=2011-07-19 }}</ref> priced at {{US$|60|1971|round=-1}}.<ref>{{cite web |first=Peter |last=Bright |title=The 40th birthday of—maybe—the first microprocessor, the Intel 4004 |publisher=arstechnica.com |date=November 15, 2011 |url=https://arstechnica.com/business/2011/11/the-40th-birthday-ofmaybethe-first-microprocessor/ |url-status=live |archive-url=https://web.archive.org/web/20170106233202/http://arstechnica.com/business/2011/11/the-40th-birthday-ofmaybethe-first-microprocessor/ |archive-date=January 6, 2017 }}</ref> The first known advertisement for the 4004 is dated November 15, 1971, and appeared in ''[[Electronic News]]''.<ref>{{Cite web|url=https://www.intel.la/content/www/xl/es/history/museum-story-of-intel-4004.html#:~:text=1971:%20Era%20of%20integrated%20electronics,wide%20variety%20of%20electronic%20devices.|title=intel's first microprocessor|access-date=2025-02-05}}</ref> The microprocessor was designed by a team consisting of Italian engineer [[Federico Faggin]], American engineers [[Marcian Hoff]] and [[Stanley Mazor]], and Japanese engineer [[Masatoshi Shima]].<ref>{{cite journal | title=The History of the 4004 | last1=Faggin | first1=Federico | last2=Hoff | first2=Marcian E. Jr. | last3=Mazor | first3=Stanley | last4=Shima | first4=Masatoshi | journal=IEEE Micro | date=December 1996 | volume=16 | issue=6 | pages=10–20 | doi=10.1109/40.546561 }}</ref>

The project that produced the 4004 originated in 1969, when [[Busicom]], a Japanese calculator manufacturer, asked Intel to build a chipset for high-performance [[desktop calculator]]s. Busicom's original design called for a programmable chip set consisting of seven different chips. Three of the chips were to make a special-purpose CPU with its program stored in ROM and its data stored in shift register read-write memory. [[Ted Hoff]], the Intel engineer assigned to evaluate the project, believed the Busicom design could be simplified by using dynamic RAM storage for data, rather than shift register memory, and a more traditional general-purpose CPU architecture. Hoff came up with a four-chip architectural proposal: a ROM chip for storing the programs, a dynamic RAM chip for storing data, a simple [[I/O]] device, and a 4-bit central processing unit (CPU). Although not a chip designer, he felt the CPU could be integrated into a single chip, but as he lacked the technical know-how the idea remained just a wish for the time being.

While the architecture and specifications of the MCS-4 came from the interaction of Hoff with [[Stanley Mazor]], a software engineer reporting to him, and with Busicom engineer [[Masatoshi Shima]], during 1969, Mazor and Hoff moved on to other projects. In April 1970, Intel hired Italian engineer [[Federico Faggin]] as project leader, a move that ultimately made the single-chip CPU final design a reality (Shima meanwhile designed the Busicom calculator firmware and assisted Faggin during the first six months of the implementation). Faggin, who originally developed the [[silicon gate]] technology (SGT) in 1968 at [[Fairchild Semiconductor]]<ref>{{cite conference | title=Insulated Gate Field Effect Transistor Integrated Circuits with Silicon Gates | last1=Faggin | first1=F. | last2=Klein | first2=T. | last3=Vadasz | first3=L. | conference=International Electronic Devices Meeting | publisher=IEEE Electron Devices Group | date=23 October 1968 | url=http://www.intel4004.com/images/iedm_covart.jpg | format=JPEG image | access-date=2009-12-23 | url-status=live | archive-url=https://web.archive.org/web/20100219143313/http://www.intel4004.com/images/iedm_covart.jpg | archive-date=19 February 2010 }}</ref> and designed the world's first commercial integrated circuit using SGT, the Fairchild 3708, had the correct background to lead the project into what would become the first commercial general purpose microprocessor. Since SGT was his very own invention, Faggin also used it to create his new methodology for [[random logic]] design that made it possible to implement a single-chip CPU with the proper speed, power dissipation and cost. The manager of Intel's MOS Design Department was [[Leslie L. Vadász]] at the time of the MCS-4 development but Vadász's attention was completely focused on the mainstream business of semiconductor memories so he left the leadership and the management of the MCS-4 project to Faggin, who was ultimately responsible for leading the 4004 project to its realization. Production units of the 4004 were first delivered to Busicom in March 1971 and shipped to other customers in late 1971.{{citation needed|date=March 2014}}