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:
Sep. 10, 1996
Filed:
May. 25, 1995
Hiroshi Komatsuda, Yokohama, JP;
Hidehiko Nishida, Inagi, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A request cancel system is incorporated in a processing system which includes a main storage unit having a plurality of banks, a memory control unit and a plurality of access units, such as central processing units (CPUs), which access the banks of the main storage unit via the memory control unit. A check part in the request cancel system detects whether or not a bank designated by an address of an access request from one of the access units is in use by reading a corresponding bank busy flag from a bank busy flag group. After the check part has determined that a bank designated by an address of a first access request is not busy, a flag is sent to the bank busy flag group to indicate that the bank accessed by the first access request is busy. A second access request to the bank accessed by the first access request can be processed by the check part before the flag is set in the bank busy flag group. A comparator compares the addresses of the first access and second access requests and outputs a coincidence signal when the addresses of the first and second access requests coincide. A request cancel controller cancels the second access request in response to the coincidence signal from the comparator.