|
Message
From: markus at reaaliaika.net<markus@r...>
Date: Thu Sep 9 09:30:04 CEST 2004
Subject: [oc] embedded clock concept
From: Dipak Modi<dipakm@e...> > What is 'embedded clock' concept? I've heard that receiver device
> extracts clock from the data at its end. Any information given
> would be appreciated.
Do you mean those serial protocols, where the encoding of the data
contains some means to synchronize the receiver to the data stream
(like USB's NRZI). The common thing is, that no matter of the data
content the line regularly changes it's state (using encoding or
synchronization patterns), so that you can synchronize the receiving to
the edges (and possibly detect the transfer speeds).
This way you don't need additional clock line in the implementation,
while still getting somewhat reliable transfers.
Google search: "return-to-zero" and "non-return to zero"
|
Browse
