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Re: [10GBASE-CX4] Signal Detect




Steve,
	This is a very valid concern.  So a question for us to answer is do we
leave it the way it is (this is straight from clause 53 which is from
clause 39 1000BASE-X) and leave it up to the implementors to design
their products so a single bit error does not cause a problem or do we
spend lots of time figuring out how to spec this to avoid this issue yet
still allow as wide open implementations as the current one allows?

Howard


"Dreyer, Steve" wrote:
> 
> Howard,
> 
> OK, but even if the intent is to spec loss of signal, the
> spec doesn't preclude an implementation losing signal on
> a single noise hit, that is my concern.
> 
> Steve
> 
> > "Dreyer, Steve" wrote:
> > >
> > > Howard,
> > >
> > > Took a quick look at the proposed draft and have the following
> > > top level comments:
> > >
> > > 7. For signal detect, it seems that a single noise pulse >100mV
> > >    would cause a signal detect OK condition.  It may be useful to
> > >    have an algorithm with improved noise rejection.
> >
> > <HAB>
> >       If you look at other Signal detect functions in 802.3
> > you'll find this
> > same issue.  The purpose is not to detect a signal but rather
> > to detect
> > that there is no signal.  The name is misleading so pay very cloase
> > attention to the wording and you'll see it actually describes
> > detecting
> > the absense of the signal.
> > <HAB>