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. 19, 1999
Filed:
Aug. 21, 1997
Michael T Klein, Ann Arbor, MI (US);
William Perry Su, Ann Arbor, MI (US);
Richard Leroy Mahn, Ann Arbor, MI (US);
Per-Ola Gustav Forsgren, Solna, SE;
Steeplechase Software, Inc., Ann Arbor, MI (US);
Abstract
A digital computer implemented software system is provided for enabling on-line programming changes of industrial logic controllers using a software package of the type utilizing graphical flowcharts is provided, allowing a user to modify a program and transfer industrial process state information while the program is controlling equipment. A control program has predetermined stop points of execution. Each stop point is assigned a unique index used to retrieve instruction addresses from an array. Each stop point also is associated with industrial process state information. By substituting new addresses pointing to stop points in a new program for the executing program addresses and transferring the state information, the executing program is replaced by a new program when execution continues on the next CPU scan. On-line programming changes take effect by replacing the executing code when all programs have reached a stop point, and by restarting a second program from the corresponding stop point in the second program.