Patent · US Expired

Method and apparatus for preventing recursion jeopardy

US5115506A · kind A · utility

23Cited by
6References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 5, 1990
Grant dateMay 19, 1992
Priority date
Expiry dateJan 5, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/462
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A microprocessor including unprime registers for use during normal operation, prime registers for use during interrupts, a normal register set for use during normal operation and conventional interrupt operations, an alternate register set for use during fast interrupt operations, and a memory stack. Three status bits are used to indicate that one or more fast interrupts have been initiated but not completed, that a fast interrupt is occurring but there are no other fast interrupts being processed, and that the CPU is currently processing a fast interrupt. These status bits indicate if there is a recursion jeopardy and are used to control the flow of information between the normal and alternate register sets and the memory stack in order to prevent recursion.

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