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. 23, 1978
Filed:
Dec. 20, 1976
John M Woods, Glendale, AZ (US);
Marion G Porter, Phoenix, AZ (US);
Earnest M Monahan, Phoenix, AZ (US);
Honeywell Information Systems Inc., Waltham, MA (US);
Abstract
An input/output processing system comprises a number of modules including at least a pair of processing units connected to operate as a logical pair and a system interface unit having a number of ports. Each port connects to a different one of the modules for interconnecting pairs of modules for communication over a number of switching circuit networks included in the system interface unit. The system interface unit further includes control logic circuits for disconnecting each processor of the logical pair preventing the disconnected processing unit from communicating with other modules. The control logic circuits further include circuits which in response to special commands from a good processor are operative to condition via a special line, circuits in the disconnected processing unit to apply status signals representative of the contents of a control register to the system interface unit. The other circuits within the system interface unit in response to a further command condition certain switching circuit networks for loading the status signals into one of the registers included in the system interface unit for subsequent analysis by system routines.