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:
Aug. 03, 1999
Filed:
Jul. 30, 1997
James D Kelly, Aptos, CA (US);
Michael L Regal, Campbell, CA (US);
Apple Computer, Inc., Cupertino, CA (US);
Abstract
A mechanism is provided for avoiding deadlock in a computer system in which a split-transaction bus is bridged to a single-envelope bus. In one embodiment, transactions begun on said split-transaction bus are monitored. When a combination of transactions would, if a predetermined further transaction were to begin, result in deadlock, this condition is detected. The predetermined further transaction, if it is requested, is refused, thereby avoiding deadlock. In accordance with another embodiment of the invention, the bus bridge detects when a state of the split-transaction bus would, if a protocol of said split-transaction bus were adhered to, result in deadlock. The bus bridge then drives one or more signals on the split-transaction bus in disregard of the protocol of the split-transaction bus, thereby avoiding deadlock. In accordance with still a further embodiment of the invention, transactions accepted within the bus bridge are monitored. When a combination of said transactions would, if a predetermined further transaction were to begin, result in deadlock, this condition is detected. The predetermined further transaction, if it is requested, is refused, thereby avoiding deadlock.