HIERACHICAL STORAGE SYSTEM AND METHOD FOR CORRECTION OF ERROR OF MICROINSTRUCTION IN HIERACHICAL STORAGE SYSTEM

摘要

PURPOSE: To recover the absence or error of a microinstruction in a microinstruction storage device with a simple device and method. CONSTITUTION: In a hierarchical memory system composed of a main storage device 10 and a secondary storage device 70, the secondary storage device 70 is divided into an area 90 for storing the microinstruction required for executing an operation and an area (buffer) 80 for storing a non-residential microinstruction paged from the main storage device 10 as needed. Devices 120, 180 and 190 check the presence/absence of the microinstruction to be decoded by a microinstruction decoder 130 in the area 80 or the parity error of the microinstruction under decoding and when the absence or error of the microinstruction is detected, the microinstruction is reloaded from the main storage device 10 to the microinstruction storage device 70 and sent to the decoder 130 later.