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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 family|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
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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
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** MOS Technology 8564 – VIC-II E C128 version
The earliest revision of the VIC-II was used in machines made during 1982 and early 1983; it had a ceramic shell for thermal reasons and generated 64 NTSC color clocks per line. These chips also did not output separated chroma and luminance signals. All later revisions had a lower cost plastic shell and 63 color clocks per line, as well as separated chroma and luminance, allowing for an early form of S-video. Several revisions were made chiefly in the interest of improving video output quality, which was poor on the early units, and eliminating a bug that would cause random pixels to appear on screen (a few early games intentionally exploited this for graphics effects that consequently did not work on later C64s). The 64 color clocks on the initial VIC-II was done with the intention of allowing NTSC artifact color in high resolution bitmap mode as the Atari 8-bit computers did, but that idea was quickly dropped.
Because it was necessary for cost reasons to switch to a plastic shell, overheating tended to be a problem with the VIC-II. This was for several reasons including the high density of the die relative to the process used, and its high internal speed (8Mhz). Commodore tried an improptu solution for this by using the aluminum RF shield as a heat sink (on NTSC machines; PAL machines were sold in countries with less restrictive RF interference standards than the United States and so only used aluminized cardboard), however it was not entirely effective at preventing overheating and chip failure.
The 85xx VIC-II used in C64Cs was made with the more modern 3.5 μm HMOS process and requires only a single 5V power rail instead of the dual 12V and 5V rails of the 65xx VIC-II. These chips run significantly cooler and do not suffer from the overheating issues that affect the 65xx VIC-II.
Several revisions of 6569 exist: 6569R1 (usually gold plated), 6569R3, 6569R4 and 6569R5. The most common version of 8565 is 8565R2.
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