Editing Processor design (section)

====Embedded processor economics====
The embedded CPU family with the largest number of total units shipped is the [[8051]], averaging nearly a billion units per year.<ref>{{cite web |url=http://people.wallawalla.edu/~curt.nelson/engr355/lecture/8051_overview.pdf |title=8051 Overview |author=Curtis A. Nelson |access-date=2011-07-10 |url-status=dead |archive-url=https://web.archive.org/web/20111009101426/http://people.wallawalla.edu/~curt.nelson/engr355/lecture/8051_overview.pdf |archive-date=2011-10-09 }}</ref>  The 8051 is widely used because it is very inexpensive.  The design time is now roughly zero, because it is widely available as commercial intellectual property.  It is now often embedded as a small part of a larger system on a chip.  The silicon cost of an 8051 is now as low as US$0.001, because some implementations use as few as 2,200 logic gates and take 0.4730 square millimeters of silicon.<ref>
{{cite web| url = http://www.keil.com/dd/docs/datashts/evatronix/t8051_ds.pdf| title = T8051 Tiny 8051-compatible Microcontroller| archive-url = https://web.archive.org/web/20110929033902/https://www.keil.com/dd/docs/datashts/evatronix/t8051_ds.pdf| archive-date = 2011-09-29}}</ref><ref>To figure dollars per square millimeter, see [http://www.overclockers.com/forums/showthread.php?t=550542], and note that an SOC component has no pin or packaging costs.</ref>

As of 2009, more CPUs are produced using the [[ARM architecture family]] instruction sets than any other 32-bit instruction set.<ref>
[http://www.extremetech.com/extreme/52180-arm-cores-climb-into-3g-territory "ARM Cores Climb Into 3G Territory"] by Mark Hachman, 2002.
</ref><ref>
[http://www.embedded.com/electronics-blogs/significant-bits/4024488/The-Two-Percent-Solution "The Two Percent Solution"] by Jim Turley 2002.
</ref>
The ARM architecture and the first ARM chip were designed in about one and a half years and 5 human years of work time.<ref>[https://web.archive.org/web/20090606152116/http://atterer.net/acorn/arm.html "ARM's way"] 1998</ref>

The 32-bit [[Parallax Propeller]] microcontroller architecture and the first chip were designed by two people in about 10 human years of work time.<ref>{{Cite web
| first=Chip | last=Gracey
| title = Why the Propeller Works
| url = http://www.parallax.com/Portals/0/Downloads/docs/article/WhythePropellerWorks.pdf
| archive-url = https://web.archive.org/web/20090419060820/http://www.parallax.com/Portals/0/Downloads/docs/article/WhythePropellerWorks.pdf
| archive-date = 2009-04-19
}}</ref>

The 8-bit [[Atmel AVR|AVR architecture]] and first AVR microcontroller was conceived and designed by two students at the Norwegian Institute of Technology.

The 8-bit 6502 architecture and the first [[MOS Technology 6502]] chip were designed in 13 months by a group of about 9 people.<ref>{{Cite web |url=http://silicongenesis.stanford.edu/transcripts/mensch.htm |title=Interview with William Mensch |access-date=2009-02-01 |archive-url=https://web.archive.org/web/20160304091031/http://silicongenesis.stanford.edu/transcripts/mensch.htm |archive-date=2016-03-04 |url-status=dead }}</ref>