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:
Jan. 12, 1993
Filed:
Aug. 29, 1989
Applicant:
Inventors:
Terence M Cole, Berkshire, GB;
Geoffrey Poskitt, Surrey, GB;
Assignee:
International Computers Limited, London, GB;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ; G06F / ;
U.S. Cl.
CPC ...
395400 ; 395425 ; 364D / ;
Abstract
A data processing unit accesses data in a cache using a virtual address. If the data is not in the cache, the virtual address is translated by a memory management unit (MMU) into a physical address for accessing a main memory. The MMU can also access the cache, using the physical address, to retrieve page table entries held in the cache. This avoids the need for a main memory access to retrieve the page table entries, and hence speeds up the address translation operation. The physically addressed entries in the cache are tagged with a reserved context number to distinguish them from the virtually addressed data.