Method and system for accurate temporal determination of real-time events within a universal serial bus system
US6012115A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 28, 1997 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Jul 28, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/426
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and system that enables real-time peripheral devices to be connected to a computer system utilizing Universal Serial Bus architecture. The present invention empowers the computer system to perform an accurate determination of the moment in time a predetermined event occurred within a real-time peripheral device by utilizing the start of frame pulse transmitted from a USB host controller to peripheral devices connected to it. When a predetermined event occurs within a peripheral device, a first timer within the peripheral device starts incrementing to determine the amount of time that elapses until the next start of frame occurs. Once the next start of frame occurs, the first timer stops incrementing and stores the time before start of frame value. Every start of frame pulse causes a second timer located within the USB host controller to start incrementing. The USB host controller interrogates the peripheral device which transfers data to the host controller indicating that (1) an event occurred and (2) the time before start of frame value of the first timer. The USB host controller interrupts the host processor and transfers it the data related to the peripheral device. Th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.