The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 05, 1983
Filed:
Jul. 16, 1980
Shigeo Shimazaki, Kanagawa, JP;
Matsushita Electric Industrial Company, Limited, Osaka, JP;
Abstract
A central processing unit of a computer system comprises a programmable logic array which is constructed of an AND matrix and an OR matrix. The AND matrix is responsive to a machine language instruction and to a number of a region for selecting one row from a plurality of rows arranged in the AND matrix. The OR matrix, which also has a plurality of rows, is responsive to the selected row for selecting one row therefrom. In each of the rows of the OR matrix a microaddress and a number of a region to be used for producing a subsequent microaddress are prewritten so that information on a microaddress and information on a region number are respectively obtained. At least one microinstruction included in a microprogram will be read out from a read-only memory in accordance with the obtained microaddress to execute the same, while a microaddress of a subsequent microprogram is produced in the programmable logic array. Namely the execution of a microprogram routine and the production of the first address of a following microprogram routine are concurrently performed so that efficient execution of microprograms can be achieved, while each microinstruction is not required to include region number information.