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. 22, 1996
Filed:
Jun. 07, 1995
Edward R Sederlund, Saginaw, MI (US);
Nadene T Thomas, Lake Jackson, TX (US);
Robert J Lindesmith, Midland, MI (US);
Russell W Cowles, Lake Jackson, TX (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
A stealth interface for an intelligent front-end communication system couples a plurality of actively redundant process control computers to a computer network. The stealth interface in each of the actively redundant process control computers includes a multi-ported memory for storing dynamic data associated with the physical process and for transferring this data to a front end computer which is in communication with the computer network. The multi-ported memory also includes a mailbox section for storing messages sent between the front end computer and its actively redundant process control computer. The stealth interface also includes a guardian circuit which ultimately controls the ability of the front end computer to write information to specific memory locations in the multi-ported data memory.