taken in the system and available for the treatment of malfunctions through a central register of states of operation in a system consisting of individual processing unit of the system

摘要

A method and apparatus for controlling the functional states of system units of a modularly constructed program controlled data processing system are described. The system units are connected through standard interface connections. The system stores all the program required for its operation in a central storage. Defective system units are placed in a testing state and isolated from the rest of the system, which can remain operative. The functional states of the individual system units can be changed manually and/or controlled automatically by a program. The individual system units indicate their respective functional states to a central station comprising a digital register over the standard interface connections, and through a storage cycle. Upon the occurrence of a defective change in functional state of one or more of the system units, the central station produces signals which bring about, either directly or through a program, a response from the processing unit assigned to the combination of the changes in the functional states at the given time.