Reliable switching between data sources in a synchronous communication system
US5872823A · kind A · utility
Inventor
Key dates
| Filing date | Apr 2, 1997 |
| Grant date | Feb 16, 1999 |
| Priority date | — |
| Expiry date | Apr 2, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/22
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
First and second data sources transmit a data signal on a data connection and a transmit clock signal on a clock connection. The data signal is clocked into a FIFO resident in the network interface equipment in response to the transmit clock signal, and out of the FIFO to the network in response to a reference clock signal. The FIFO generates a signal indicating how full it is and a local clock generator which generates the transmit clock signal in response to this status indication signal. The first and second data sources hold the data signal and transmit clock signal high for longer than a single period of the reference clock signal when switching between them. The local clock generator alters an average rate of the transmit clock signal in response to the status indication signal from the FIFO in order to keep it half-full.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.