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RE: [802.3ae] 64/66b Encoding phenomena




Thomas,

On Sat, 2002-05-25 at 04:22, ti wrote:
> 
> Hi Justin,
> 
> [...]
> 
> > This data stream can be interpreted two different ways depending on
> > where the 64 bit boundary falls.
> >
> > 1.  DDDD_DDDT, IIIE_EIII, SDDD_DDDD with block type fields of FF, 1E,
> > and 78 respectively. (T C S)
> >
> > 2.  DDDT IIIE, EIII SDDD corresponding to block type fields
> > of B4 and 33
> > respectively, these are T_BLOCK_TYPES of T and S.
> 
> [...]
> 
> > Resulting in 1. becoming /T/ /E/ /S/
> 
> I agree.
> 
> > while 2. would remain  /S/ /T/
> 
> Did you mean /T/ /S/?

Yes, sorry.

> 
> And where is the problem? Did I understand something wrong?
> I see no /E/- Types!

The issue is that under one condition, you get an /E/ and a drop frame,
and under another condition, you dont.  With the exact same bit stream.

> 
> regards,
> thomas
> 
> 
-- 
Justin Gaither                           Phone: 512-306-7292  x529
Xilinx, Communications Technology Div.   Fax:   512-306-7293
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