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. 24, 1989
Filed:
Jul. 17, 1987
John R Marum, Stanford, CA (US);
TRW Inc., Redondo Beach, CA (US);
Abstract
An electronic system having multiple identical subsystems, some of which can be excluded from the system when defective or held as spares. A mapping circuit associated with each subsystem has a first register for storing a physical address of the subsystem and a second register for storing a logical address. To configure the system to include a selection of subsystems, pairs of physical and corresponding logical addresses are transmitted to the subsystem mapping circuits. When a transmitted physical address matches the address stored in the first register, the second register is enabled to receive a transmitted logical address. The mapping of physical to logical address is therefore distributed among all of the subsystems rather than being handled in a central mapping unit. Subsystems that are to remain out of service have a null address stored in their second registers. In normal operation of the entire system, a logical address transmitted to the subsystems is compared with the logical address stored in each second register, and only the matching subsystem is selected for operation.