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. 15, 1985
Filed:
Sep. 30, 1982
David J Brahm, Naperville, IL (US);
James M Grinn, Warrenville, IL (US);
Edward L Hepler, Woodridge, IL (US);
John M Sullivan, Lisle, IL (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
In a communication system which includes a plurality of stations interconnected for communications by a first bus, a second station includes a device, such as a processor, and a resource, such as a memory or a peripheral unit, interconnected for communication by a second bus. An interface mechanism connecting the first bus with the second bus allows the device to access the first bus over the second bus, and allows a first station to access the resource via the first and second buses. Deadlock detection circuitry detects cotemporaneous attempts by the device to access the first bus and attempts by the first station to access the resource. Deadlock resolution circuitry responds to deadlock detection by disconnecting the device from the second bus to allow the first station to access the resource, and by reconnecting the device to the second bus when the first station ceases to access the resource. If the device is operating under program control, the deadlock detection and resolution are transparent to the program.