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:
May. 30, 1989
Filed:
Oct. 20, 1986
Hitachi Ltd., Tokyo, JP;
Hitachi VLSi Engineering Corp., Tokyo, JP;
Abstract
In duplicated equipment including main equipment, duplicated subordinate equipment, and a communication line for transferring data between the main equipment and the duplicated subordinate equipment and for sending a changeover signal which can put one and the other of a pair of subordinate devices making up the duplicated subordinate equipment in an active state and a standby state, respectively, from the main equipment to the duplicated subordinate equipment, each of the subordinate devices includes means for putting the other subordinate device in the standby state, to prevent both of the subordinate devices from being put in the active state when a failure occurs on a transmission path between the communication line and one of the subordinate devices.