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:
Oct. 12, 1976
Filed:
May. 30, 1974
John G Valassis, Elmwood Park, IL (US);
James R Holden, Chicago, IL (US);
Madhukumar A Mehta, Gujrat, IN;
GTE Automatic Electric Laboratories Incorporated, Northlake, IL (US);
Abstract
An expandable modular control system with reduced memory requirements comprising an electronic data processing (EDP) system employing a microprocessor device and having gated program interrupt means. In particular, the expandable modular control system of the present invention comprises a 'universal' microprocessor module which can be selectively combined with other separately packaged peripheral support modules to implement any particular control system required. Control point modules comprising a matrix array of flip-flops arranged as a plurality of n-bit words and subject to program control serve as extensions of the memory module to control the states of corresponding points in the system under the control of the modular control system. Sense point modules similarly organized in a matrix array monitor or sense the status of the points in the system under control and provide input data to the microprocessor module. Since the status of the C,Z,S and P flag bits cannot be restored the gated interrupt means also included selectively gate waiting program interrupts, if any, to the microprocessor coincident with a 'gate interrupt' instruction in the program being executed so that a subroutine can be executed before the program is resumed thereby enabling the microprocessor to function as a virtually interruptable CPU.