SIERRA

Sierra was one of Atari's projects to design a 16-bit computer.  Due to too many people being involved with the project's design, nobody could decide on which direction to go with it (ex: which processor to use, how much memory it was to have, what size disk drive should be used, etc).  The team couldn't even decide on which OS to use - VisiCorp's new "Visi On" Windowing Operating system (just released in 1983), or Atari's own custom Windowing OS running on a version of BSD Unix (being developed under the name Project "Snowcap").

The custom chipset was being developed separately Ted Kahn and Chris Jeffers in Atari's Corporate Research group at (1196 Borregas) and was called "Rainbow".  It consisted of an advanced sound processor capable of up to 64 channels.  The graphics chips were called "Silver" (the sprite generator) and "Gold" (the graphics display list processor).  The design was scalable; the more sprites needed, the more Silvers that could be added onto it.

Due to Atari's own Industrial Design group not being involved with the project, a rough mock-up case was designed (photo below).