A processor family for personal computers

Multiple window user interfaces executing on personal computers require high-performance hardware support. The Intel 80286 offers designers direct hardware support for multitasking as well as memory management and protection. A consistent segmented model of memory provides a direct path for object code compatibility with the 8086/8088 CPU chip, and eases program development in the 80286´s protected virtual address environment. In this protected mode, sophisticated protection policies, including those for secure operating systems, are available. This processor uses a four-stage pipelined architecture that includes autonomous prefetch, instruction decode, execution, and address translation. The architectural highlights of the 80286 chip are described in this paper.