Patent · US Expired

Method and apparatus for controlled removal and insertion of circuit modules

US4835737A · kind A · utility

258Cited by
15References
20Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJul 21, 1986
Grant dateMay 30, 1989
Priority date
Expiry dateJul 21, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F13/4081
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An electronic circuit board electrically connected to other circuits of a data processing system by means of a bus, may be removed and re-inserted in the system without the necessity of disabling other circuits connected to the bus. A latch actuated switch provides a control signal in anticipation of circuit board removal. The control signal activates a finite state machine which seizes control of the bus after completion of any current bus communications and stops the generation of clock pulses normally required in bus communications. When contact is physically broken between the board and its corresponding connector, the finite state machine restores the bus clock pulses and relinquishes control of the bus. When a board is to be inserted in an open connector, contact between the board and the connector is sensed by the finite state machine which causes the bus to be seized and the bus clock pulses to be temporarily inhibited. When the board is fully inserted, the finite state machine restores the bus clock pulses and relinquishes control of the bus.

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