Apparatus and method for driving a bus to a docking safe state in a dockable computer system including a docking station and a portable computer
US5598537A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 1994 |
| Grant date | Jan 28, 1997 |
| Priority date | — |
| Expiry date | Jul 26, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/4081
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a dockable computer system capable of hot docking or warm docking, a docking safe circuit drives the bus of the portable computer and docking station to a docking safe state in response to a DOCK signal. The DOCK signal may be a notice signal indicative of a change of state from the undocked state to the docked state or from the docked state to the undocked state. The notice signal may be provided from software, a user-actuated switch or an infrared signal. Preferably, the docking safe state or dockable state is a state in which: the ground conductors of the buses are referenced to a common ground potential; the buses are "quiet" or non-transitioning; the bidirectional terminals on the bus of the portable computer are set to an output state; the bidirectional terminals of the bus of the docking station are set to an input state; and the signaling levels of the buses have the same voltage potential. Preferably, the present invention is implemented on a peripheral component interconnect (PCI) bus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.