Patent · US Expired

Diagnostic aid for industrial controller using multi-tasking architecture

US5844795A · kind A · utility

42Cited by
7References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 22, 1996
Grant dateDec 1, 1998
Priority date
Expiry dateMay 22, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P90/80
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A task executed on a multi-tasking industrial controller is employed to monitor data exchanged between a control program (executed as a second task on the industrial controller) and the controlled process. The monitoring task, which may be invoked on a periodic basis, reads designated data, compares it to its last value and if it changes, stores the value in a buffer. A separate program reads this buffer and displays relevant information to the user minimizing degradation in the performance of the control program and eliminating the possibility of corruption of the control program as would be required for the introduction of special memory trapping instructions into the control program.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.