Microinstruction execution unit for use in a microprocessor

摘要

An execution unit which is part of a general-purpose microprocessor, partitioned between two integrated circuit chips, with the execution unit on one chip and an instruction unit on another chip. The execution unit provides the interface for accessing a main memory to thereby fetch data and macroinstructions for transfer to the instruction unit when requested to do so by the instruction unit. The execution unit receives arithmetic microinstructions in order to perform various arithmetic operations, and receives access-memory microinstructions in order to develop memory references from logical addresses received from the instruction unit. Arithmetic operations are performed by a data manipulation unit which contains registers and arithmetic capability, controlled by a math sequencer. Memory references are performed by a reference-generation unit which contains base-and-length registers and an arithmetic capability to generate and check addresses for referencing an off-chip main memory, and is controlled by an access sequencer.