Patent · US Expired

Interrupt control system for microprocessor for handling a plurality of maskable interrupt requests

US5349667A · kind A · utility

42Cited by
8References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 8, 1992
Grant dateSep 20, 1994
Priority date
Expiry dateSep 8, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F13/24
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A microcomputer includes a maskable interrupt request terminal, a maskable interrupt request terminal, and a nonmaskable interrupt request terminal, and internally contains a status register having a group of flags indicating a maskable interrupt allowing level, a flag indicating that a nonmaskable interrupt processing is under execution, a flag indicating that an exception processing is under execution, and a flag indicating inhibition of the maskable interrupt. There are also internally provided first and second save registers for saving the content of the status register and the content of a program counter, respectively, when the maskable interrupt request is acknowledged, and third and fourth save registers for saving the content of the status register and the content of a program counter, respectively, when the nonmaskable interrupt request is acknowledged. A register is provided to independently indicate the acknowledgement of the maskable interrupt and the acknowledgement of the nonmaskable interrupt, and a comparator compares the level designated by the maskable interrupt allowing level indicating flag group with an interrupt request level notified through the maskable int…

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