Encyclopedia > Co-processor

  Article Content


A co-proccessor is a secondary processor in a computer that handles tasks that the general-purpose CPU either cannot implement, or does not implement for efficiency reasons. This is distinct from the term multiprocessor, which refers to a computer with more than one general-purpose CPU.

Co-processors were first seen on mainframe computers, where they added additional "optional" functionality such as floating point math support. A more common use was to control input/output channels, although in this role they were more often referred to as channel controllers.

Co-processors also became common in desktop computers thoughout the 1980s and into the early 1990s due to CPU design limitations and cost considerations. The math co-processor was a common addition to high-end computers like the Mac II and most workstations that required the capability to do floating-point arithmetic, but until the early 1990s the demand for such capabilities was minimal. Another form of co-processor that became common during this era was the graphics co-processor, used in the Atari 8-bit family and Commodore Amiga. The graphics processor chip in the Commodore series was known as the "Copper."

Eventually, the functionality of the math co-processor was of enough importance to be integrated into the primary CPU, eliminating the need for a separate component. The demand for a dedicated graphics co-processor has grown, however, particularly due to an increasing demand for realistic 3D graphics in computer games; this dedicated processor removes a considerable computational load from the primary CPU, and increases performance in graphic-intensive applications. As of 2002, graphics cards with dedicated Graphics Processing Units (GPUs) are commonplace.

All Wikipedia text is available under the terms of the GNU Free Documentation License

  Search Encyclopedia

Search over one million articles, find something about almost anything!
  Featured Article
Quadratic formula

... The formula reads <math> x=\frac{-b \pm \sqrt {b^2-4ac}}{2a} </math> The term b2 – 4ac is called the discriminant of the quadratic ...

This page was created in 25.7 ms