Patent · US Expired

Multiple comparison circuitry for providing a software error trace signal

US4453093A · kind A · utility

12Cited by
3References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 2, 1982
Grant dateJun 5, 1984
Priority date
Expiry dateApr 2, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/30029
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Apparatus and method for performing a logical not function in a multi-compare environment is disclosed. By performing two equivalence compares of a measured variable against selectable target values and using the result of the equivalence compares to selectivity set or reset a bistable element, the need for inverting and multiplexing the output of a comparator that is otherwise required when performing a NOT equivalence function in a single-compare environment is eliminated. The not function logic is used in a system analyzer connected to a data processing system and is used to selectively enable the tracing of software execution as a function of whether or not a variable is a predefined value.

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