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:
Feb. 12, 1991
Filed:
Oct. 17, 1988
Applicant:
Inventors:
Donald R Janke, Milwaukee, WI (US);
Kim J Watt, Milwaukee, WI (US);
Dirk I Gates, Woodland Hills, CA (US);
Joseph T Bronikowski, Brown Deer, WI (US);
Assignee:
Square D Company, Palatine, IL (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G06F / ; G06F / ;
U.S. Cl.
CPC ...
364134 ; 364140 ; 364900 ; 3649269 ; 3649314 ; 3649421 ; 364949 ; 364951 ;
Abstract
A communication network for programmable logic controllers (PLC) wherein selected memory means of each PLC has at least two ports directly accessible by other PLC and certain registers of the PLC are identical. Each PLC further has an interblock gap timer to signal the PLC when its transmit time slice is to occur. The time slice consists of a block transmit time and an interblock gap time. The total update time has been optimized to engable efficient, high-speed transfer of blocks of data between the PLCs.