Patent · US Expired

Option unit detecting apparatus for electronic equipment

US4951235A · kind A · utility

8Cited by
1References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 19, 1989
Grant dateAug 21, 1990
Priority date
Expiry dateApr 19, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F13/4063
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An option unit detecting apparatus detects whether an option unit is connected to or disconnected from an electronic equipment. The electronic equipment includes an electronic circuit having an input/output port, and the option unit includes at least one semiconductor device. When the option unit is disconnected from the electronic unit, a switching element is rendered ON and a low-level signal is applied to the input/output port of the electronic circuit. When the option unit is connected thereto, the switching element is rendered OFF and a high-level signal is applied thereto. Accordingly, it is possible to detect whether the option unit is connected to or disconnected from the electronic unit based upon the level of the signal applied to the input/output port.

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