USB transaction translator with SOF timer and USB transaction translation method for periodically sending SOF packet
US9009380B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2013 |
| Grant date | Apr 14, 2015 |
| Priority date | — |
| Expiry date | Sep 26, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/4059
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A universal serial bus (USB) transaction translator is provided along with a micro-frame synchronization method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus. At least two buffers are configured to store data. A controller stores the data in the buffers alternately. A start-of-frame (SOF) counter is used to count the SOF packets, with the counting value of the SOF counter being compared to a predefined value. Specifically, the controller resets a SOF timer for sending the SOF packet when the counting value achieves or exceeds the predefined value, such that the SOF packet and an isochronous timestamp packet (ITP) from the host are sent at the same time. Further, the controller delays the sending of the SOF packet for a period of time according to the ITP from the host.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.