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.