Patent ID: 7106822

Claim:
A bidirectional synchronous interface for a digital circuit configured for the reception of a first flow of digital data from a remote circuit with a first coding on a first communication channel, and for transmission to the remote circuit on a second communication channel of a second flow of digital data received from the digital circuit with a second coding and encoded with the first coding in synchrony with a local timing signal, the bidirectional synchronous interface comprising: synchronization means for synchronizing the interface with the first flow of digital data with the second coding, said synchronization means comprise first circuit means that comprise a delay locked loop circuit fed by said local timing signal generated from a single time base in order to derive, starting from said local timing signal, a plurality of repetition timing signals delayed from one another by fractions of a period and a transmission timing signal; second circuit means fed by said first flow of digital data and by said plurality of repetition timing signals suitable for determining the repetition timing signal from the plurality of repetition timing signals that is substantially in synchrony with the first flow of digital data with the second coding, said second circuit means comprise a selector that receives said plurality of repetition timing signals and delivers one of said plurality of repetition timing signals to phase comparing means that compare the repetition timing signal delivered by the selector with the first flow of digital data, said phase comparing means operating the selector as a function of the phase difference found so that the repetition timing signal delivered by the selector is delayed to a greater or lesser degree with respect to the local timing signal, whereby the reception of the first flow of digital data and the transmission of the second flow of digital data use a single time base; and means for decoding the first flow of digital data, fed by the repetition timing signal to decode the first flow of digital data by converting the first coding into the second coding, wherein said first coding is of a Coded Mark Inversion (CMI) type, and said second coding is of a Non-Return to Zero (NRZ) type, and means for converting the second flow of digital data, fed by the transmission timing signal from the second coding to the first coding.