Re: [oc] High speed serial comms links

[Wenyi Feng <wenyi@agere.com>]

Hi,

I think what you want is the SERDES capabilities.
A SERDES has a transmit section and a receiver
section; the transmit portion integrates data with
a clock signal to modulate the clock pulse (typically
removing the clock pulse when data value is '0');
The receiver portion finds both the underlying clock
and the stream of data from this modulated clock
signal, this is also know as clock/data recovery (CDR).
So, SERDES requires no seperate channel to do 
synchronization. ALso, because SERDES part runs at very
high rate, 1.25GB/s - 3.125 GB/s, it is always
built as an asic block.

The above info is from a training course material. Standalone
SERDES devices are available from Vitesse, conexant, Broadcom, 
Agere, TI and so on. However, if you want a single device 
containing both SERDES block and FPGA logic, you may 
consider Altera's Mercury or Agere's ORT82G5 devices.

Wenyi




Carl van Schaik wrote:
> 
> Hi
> 
> I have a board design with 4 LVDS transmit and 4LVDS recieve pairs and I'm
> looking to
> get a high speed comms system to run across it.
> 
> I want to use 2TX and 2RX lines, I have two RJ45 connectors
> with 2TX and 2RX pairs each.
> 
> I have already tested the recievers and transmitters by sending a 266MHz
> clock
> (533MBits/s theoretical max data rate) over
> a piece of CAT-5 cable and verified its reception.
> I now want to design a high speed serializer/deserializer over 2 LVDS
> channels (single direction)
> 
> I'm a bit at a loss as to the best way to do this...
> 
> Sending Clock and Frame data requires two channels alone in synchronous
> comms.
> 
> I'll be wanting a way to embedd the clock, data and frame over the 2 signals
> in a way
> to maximise the bandwidth.
> The comms will be eventually implmented between two separate boards that
> don't have
> synchronised clocks so the design must cater for this.
> 
> any input would be great.
> 
> Hey, if it works out, it could become anouther opencores core.
> 
> thanks
> Carl van Schaik
> --
> OpenFuel Pty Ltd.
> 
> --
> To unsubscribe from cores mailing list please visit http://www.opencores.org/mailinglists.shtml
--
To unsubscribe from cores mailing list please visit http://www.opencores.org/mailinglists.shtml