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Re: SJTP:Phantom sync headers





Don,

This is a good point. Especially with such a short
pattern, it may be difficult for the receiver to
power up "knowing" where it is in the

Seed A
Seed A Invert
Seed B
Seed B Invert

loop. There may be many errors in the beginning while
waiting to sync up on the pattern... As we develop
seeds, this is another aspect of the project that
could greatly benefit from PCS simulations.

Ben

"Alderrou, Don" wrote:
> 
> Ben,
> 
> Another issue which I've not heard discussed is in the receiver error
> detection logic.  Once the 64B/66B receiver has Block_Lock, the error
> detection logic needs to find "pattern sync" at the beginning of the jitter
> test pattern.  The pattern as proposed will invert the data & scrambler
> seed, thus the receiver needs to also do this at the proper time to check
> for errors.  If the data & seed are not chosen wisely, there could be
> similar "phantom pattern sync" issues.  A simple way around this is to have
> some "sync frames" similar to the WAN A1/A2 as part of the pattern.
> 
> --Don
> 
> > -----Original Message-----
> > From: Ben Brown [mailto:bbrown@amcc.com]
> > Sent: Thursday, May 10, 2001 9:59 AM
> > To: serialpmd
> > Subject: SJTP:Phantom sync headers
> >
> >
> >
> > All,
> >
> > Jonathan brought up an interesting point that I have
> > elaborated upon below. Those who have begun or are
> > interested in beginning to search for patterns should
> > probably keep this in mind.
> >
> > Ben
> >
> > --
> > -----------------------------------------
> > Benjamin Brown
> > AMCC
> > 2 Commerce Park West
> > Suite 104
> > Bedford NH 03110
> > 603-641-9837 - Work
> > 603-491-0296 - Cell
> > 603-626-7455 - Fax
> > 603-798-4115 - Home Office
> > bbrown@amcc.com
> > -----------------------------------------
> >


-- 
-----------------------------------------
Benjamin Brown
AMCC
2 Commerce Park West
Suite 104 
Bedford NH 03110
603-641-9837 - Work
603-491-0296 - Cell
603-626-7455 - Fax
603-798-4115 - Home Office
bbrown@amcc.com
-----------------------------------------