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:
Jun. 29, 1976
Filed:
Dec. 30, 1974
Yukio Taniyama, Yokohama, JA;
Tetsuo Isaka, Yokohama, JA;
Tetsuo Nagahori, Kawasaki, JA;
Kaoru Kanda, Yokohama, JA;
Fujitsu Ltd., Kawasaki, JA;
Abstract
A selection system for an information processing system wherein a unit, such as a magnetic tape unit, is shared by a plurality of control units. At least first and second signal lines are connected between each control unit at a driver circuit and a receiver circuit pair. The two signal lines connected between each control unit correspond to a single shared unit, and each control unit provides a driver circuit and a receiver circuit connected so as to transmit and receive signals carried on each line. Each line is connected to a separate driver circuit and receiver circuit at each control units. A block signal is transmitted from one of the control units through a first signal line to the other control units to prevent them from starting their operation for accessing the shared unit, and selection signals are transmitted from possible plurality of started control units through the second signal line at different timings to thereby determine priority of the started control units for accessing the shared unit. With this system, the control units can be correctly operated in accordance with priority by simple circuit construction without employing a scanning system, and further, the number of control units can be increased without increasing the cost of the selection system.