Editing Microprocessor (section)

====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.