Method of maintaining a USB active state without data transfer
US7873841B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2006 |
| Grant date | Jan 18, 2011 |
| Priority date | — |
| Expiry date | Feb 20, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D10/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A USB bus-powered device in Suspend state that requires active bus state power levels, but has no data transfer need, may initiate Resume signaling to return a USB bus segment to active state, without transferring any data across the bus. A device driver considers both USB device power needs and data transfer activity in deciding to Globally or Selectively Suspend a bus or bus segment. In particular, upon deciding to Suspend a bonus or bus segment, the device driver queries a USB bus-powered device. If the device will require active bus mode power within a predetermined duration, the device will indicate to the device driver to remain an active mode. In this case, the device driver does not direct the USB host to Suspend the bus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.