Intel 80287

From Encyc

The intel 80287 was a floating point co-processor to intel's 80286 models of single chip computer.[1][2] The 80287 was introduced in 1982.

Integer arithmetic requires much less silicon real estate to implement than calculations on values that had a fractional component.[3] Intel off-loaded the hardware to perform those instructions to a co-processor -- a support chip devoted solely to that task.[4] Computers could be equipped with an 80286, and without an 80287. If the 80287 were present floating point instructions would be off-loaded and executed relatively quickly, by the 80287.

The intel 80287 is reported to use the same execution unit as the intel 8087.[2]

Other chips which were lineal ancestors to the Pentium microprocessor, the intel 80186 and the intel 80386, had a companion floating point co-processor manufactured to accompany it. Intel was to market an intel 80487. But it was not a separate chip, different from the intel 80486.

References[edit]

  1. "Advanced Micro promotes its power-saving answers to intel 80287 in the UK". Computer Business Review. 1990-08-22. Retrieved 2008-11-27. mirror
  2. 2.0 2.1 "intel 80287: Technical Specification". Retrieved 2008-11-27. mirror
  3. Omar Alvarado, Thomas J. Fellers, Michael W. Davidson. "Intel 387 Math Coprocessor". Olympus Micro. Retrieved 2008-11-27.CS1 maint: multiple names: authors list (link) mirror
  4. "Intel and Floating Point: Updating One of the Industry's Most Successful Standards" (PDF). intel. Retrieved 2008-11-28.