Editing MOS Technology VIC-II (section)

==Development history==
The VIC-II chip was designed primarily by Albert Charpentier and Charles Winterble<ref>{{Cite web|last=Pierceall|first=Kimberly|title=Turns out, the leader of the Commodore 64 engineering team retired to Yorktown|url=https://www.pilotonline.com/business/article_0da0c8f0-5199-50c0-8398-0a751a7e6467.html|access-date=2021-10-12|website=pilotonline.com}}</ref> at [[MOS Technology|MOS Technology, Inc.]] as a successor to the [[MOS Technology VIC|MOS Technology 6560 "VIC"]]. The team at MOS Technology had previously failed to produce two graphics chips named ''MOS Technology 6562'' for the Commodore TOI computer, and ''MOS Technology 6564'' for the Color PET, due to memory speed constraints.<ref>{{cite book
| last       = Bagnall
| first      = Brian <!-- DO NOT READD authorlink. This is a different Brian Bagnall-->
| title      = On the Edge: The Spectacular Rise and Fall of Commodore
| edition    = 1
| year       = 2005
| publisher  = Variant Press
| location   = Winnipeg, Manitoba
| isbn       = 0-9738649-0-7
| pages      = 224&ndash;225
| chapter    = The Secret Project 1981
}}</ref>

In order to construct the VIC-II, Charpentier and Winterble made a market survey of current [[home computer]]s and [[video game]]s, listing up the current features, and what features they wanted to have in the VIC-II. The idea of adding sprites came from the [[TI-99/4A]] computer and its [[Texas Instruments TMS9918|TMS9918]] [[Video Display Controller|graphics coprocessor]]. The idea to support [[collision detection]] came from the [[Intellivision|Mattel Intellivision]]. The [[Atari 8-bit computers|Atari 800]] was also mined for desired features, particularly bitmap mode, which was a desired goal of the MOS team as all of Commodore's principal home computer rivals had bitmap graphics while the VIC-20 only had redefinable characters.<ref name="IEEE1985">{{cite journal
 | last1      = Perry
 | first1     = Tekla S.
 | last2      = Wallich
 | first2     = Paul
 | date       = March 1985
 | title      = Design case history: the Commodore 64
 | journal    = IEEE Spectrum
 | volume     =22
 | issue      =3
 | pages      = 48–58
 | location   = New York, New York
 | publisher  = [[Institute of Electrical and Electronics Engineers]]
 | doi = 10.1109/MSPEC.1985.6370590
 | s2cid = 11900865
 | issn       = 0018-9235
 | accessdate = 2011-11-12
 | url        = https://spectrum.ieee.org/ns/pdfs/commodore64_mar1985.pdf
| archive-url = https://web.archive.org/web/20120513181613/http://spectrum.ieee.org/ns/pdfs/commodore64_mar1985.pdf
| url-status = dead
| archive-date = May 13, 2012
}}</ref><ref>{{cite book
| last       = Bagnall
| first      = Brian <!-- DO NOT READD authorlink. This is a different Brian Bagnall-->
| title      = On the Edge: The Spectacular Rise and Fall of Commodore
| edition    = 1
| year       = 2005
| publisher  = Variant Press
| location   = Winnipeg, Manitoba
| isbn       = 0-9738649-0-7
| page       = 227
| chapter    = The Secret Project 1981
}}</ref> About 3/4 of the chip surface is used for the sprite functionality.<ref>{{cite book
| last       = Bagnall
| first      = Brian <!-- DO NOT READD authorlink. This is a different Brian Bagnall-->
| title      = On the Edge: The Spectacular Rise and Fall of Commodore
| edition    = 1
| year       = 2005
| publisher  = Variant Press
| location   = Winnipeg, Manitoba
| isbn       = 0-9738649-0-7
| page       = 229
| chapter    = The Secret Project 1981
}}</ref>

The chip was partly laid out using [[electronic design automation]] tools from ''Applicon'' (now a part of [[UGS Corp.]]), and partly laid out manually on [[Vellum#Paper vellum|vellum paper]]. The design was partly debugged by fabricating chips containing small subsets of the design, which could then be tested separately. This was easy since MOS Technology had both its [[research and development]] lab and semiconductor plant at the same location. The initial batch of test chips came out almost fully functional, with only one bad sprite.<ref>{{cite book
| last       = Bagnall
| first      = Brian <!-- DO NOT READD authorlink. This is a different Brian Bagnall-->
| title      = On the Edge: The Spectacular Rise and Fall of Commodore
| edition    = 1
| year       = 2005
| publisher  = Variant Press
| location   = Winnipeg, Manitoba
| isbn       = 0-9738649-0-7
| page       = 230
| chapter    = The Secret Project 1981
}}</ref> The chip was developed in 5 micrometer technology.<ref name="IEEE1985"/>

The work on the VIC-II was completed in November 1981 while [[Robert Yannes]] was simultaneously working on the [[MOS Technology SID|SID]] chip. Both chips, like the [[Commodore 64]], were finished in time for the [[Consumer Electronics Show]] in the first weekend of January 1982.<ref>{{cite book
| last       = Bagnall
| first      = Brian <!-- DO NOT READD authorlink. This is a different Brian Bagnall-->
| title      = On the Edge: The Spectacular Rise and Fall of Commodore
| edition    = 1
| year       = 2005
| publisher  = Variant Press
| location   = Winnipeg, Manitoba
| isbn       = 0-9738649-0-7
| page       = 242
| chapter    = The Secret Project 1981
}}</ref>