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AssigneeInternational Business Machines Corporation
InventorsLothar A. Doehle, Heinz Drescher, Hans H. Lampe, Werner Pohle, Peter Rudolph
Estimating the term…
A priority control circuit for establishing connections between a data handling system element and a number of subsystems wherein request signals from subsystems are scanned and granted service in a sequence which is determined by their position in a priority ranking order. The scanner returns to the beginning of the order immediately after a request has been granted, the subsystem just serviced being bypassed in the next scan until all of the remaining request signals have been processed. Each time a request signal is encountered and service granted, the scanner returns to the beginning of the order, a new scan is begun and all prior requests serviced are bypassed. In the absence of any other requests or after all of the request signals have been serviced the bypassed subsystems are unlocked and a scan of all requests is begun.
For use with a plurality of system elements arranged in a ranking order, wherein said elements independently issue request signals for service, a priority circuit comprising:
A priority circuit comprising:
A priority control circuit, useful for establishing connections between several independent parts and one common part of a data processing system, in particular between the external units associated with individual input/output lines and the central storage, individual request signals from said independent parts being cyclically scanned and conditionally serviced in predetermined sequence in accordance with their priority, characterized by:
Dependencies are inferred from the claim text.