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:
Mar. 27, 2012
Filed:
May. 05, 2010
Ryohei Higuchi, Kanagawa, JP;
Ryohei Higuchi, Kanagawa, JP;
Renesas Electronics Corporation, Kanagawa, JP;
Abstract
In a hierarchical bus structure employing a fixed-priority bus access arbitration scheme, accurate arbitration of bus access requests can be carried out even in situations where priority levels are updated according to a system operation mode. In each of a plurality of superordinate hierarchical bus circuits, access requests from respective bus masters included in each corresponding bus master group are arbitrated according to priority levels assigned thereto, and based on the result of the arbitration, a priority communication signal PRA/PRB indicating a priority level of each access-request-permitted bus master is fed to a subordinate bus controller. In a subordinate hierarchical bus circuit, under control of the subordinate bus controller, access request arbitration is carried out according to the priority communication signal PRA/PRB to select a superordinate hierarchical bus circuit or bus master having the highest priority level.