Patent · US Expired

Processor system with interrupt discrimination

US5495616A · kind A · utility

7Cited by
2References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 14, 1994
Grant dateFeb 27, 1996
Priority date
Expiry dateJun 14, 2014

Classification

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

Abstract

An interrupt-driven processor system comprising a processor connected via a plurality of processor input and output lines to a keypad or keyboard. Actuation of one of the keys of the keypad or keyboard generates an interrupt signal on one of the input lines which invokes an interrupt service routine in the processor. A secondary interrupt source can be attached via an interrupt line to each of the input lines with the interrupt service routine being designed to discriminate between an interrupt signal generated by actuation of a key and an interrupt signal generated by a secondary source. Using this technique, further interrupts can be added to an off-the-shelf processor including keypad interrupts without the need for additional interrupt controlling hardware. Furthermore, a custom-built microprocessor can be designed with fewer interrupt pins.

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