Patent · US Expired

Programmable controller with multiple priority level task processing

US5193189A · kind A · utility

96Cited by
20References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 9, 1991
Grant dateMar 9, 1993
Priority date
Expiry dateDec 9, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/15081
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A programmable controller for operating a machine to perform programmed functions allows the user to allocate the amount of processing time to be devoted to a machine control program and to user defined background tasks. The allocation is defined by an entry stored in one of several locations in a data table. Each occurrence of a timed interrupt steps the operating system through the data table. When the operating system accesses the location at which the entry is stored, the machine control program is assigned as lower execution priority than any background tasks to be executed. When the last storage location of the data table is accessed, the user control program is restored to a higher execution priority than the background tasks before initiating another stepping sequence through the data table.

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