David E Gee

US Patent:

62265555, May 1, 2001

Filed:

May 14, 1998

Appl. No.:

9/079010

Inventors:

Chuck E. Kallal - Ann Arbor CA
Mike W. Messick - Whitmore Lake MI
Kevin P. Aretha - Saline MI
Jason A. McLees - Northville MI
David J. Gee - Ann Arbor MI
Richard L. Mahn - Ann Arbor MI
Don C. Stokes - Ann Arbor MI

Assignee:

Steeplechase Software, Inc. - Ann Arbor MI

International Classification:

G05B 1101

US Classification:

700 21

Abstract:

A software logic controller using flowchart programming includes exception handling elements for handling exception conditions in a manufacturing process. Exception handling is programmed using a Begin Exception element to start monitoring the occurrence of a specific exception condition and an End Exception element to stop the monitoring process. Monitoring is conducted once during every scan cycle of the computer as long as the Begin Exception element is still active.

US Patent:

54714613, Nov 28, 1995

Filed:

Apr 28, 1993

Appl. No.:

8/054581

Inventors:

Jonathan R. Engdahl - Saline MI
Mark A. Lucak - Saline MI
David J. Gee - Ann Arbor MI
Paul Kucharski - Saline MI

Assignee:

Allen-Bradley Company, Inc. - Milwaukee WI

International Classification:

H04L 1224

US Classification:

370 17

Abstract:

A moderator on a communication network periodically transmits a set of parameters for a protocol that is used to communicate over the network. Each node on the network compares the set of protocol parameters from the moderator to a set of parameters stored in that node. If the sets of parameters at a given node do not match, that given node ceases transmitting messages over the network until either the set of protocol parameters from the moderator match the stored set of parameters, or a matching set of parameters is stored in the node. Typically the active node that is assigned the lowest numerical network address functions as the moderator. However, an automatic process is utilized to prevent a node with a non-matching set of the protocol parameters from becoming the moderator for more than a brief period of time. An override procedure is provided to force all the nodes on the network to adopt a common set of protocol parameters in the event that the automatic process fails.