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RE: Interface reality check

Oops, that might have been an error on my part.  Too much travel, not enough
sleep.  What I was trying to get at is that it would be easier to solve the
XAUI EMI via the RS.  Currently, the RS is pretty much an empty layer in
802.3.  The concept I was thinking of was to use the RS to generate a
"designed" idle pattern rather than our usual data = 0x00.  That would
result in the XGXS operating as a four lane 8b/10b encoder/decoder.  It
would also generate an 8-bit representation of /a/, /k/ and /r/ for use by
Rick Walker's 64/66 encoder/decoder.

Just food for thought.


		-----Original Message-----
		From:	Brown, Ben [BAY:NHBED:DS48]
		Sent:	Wednesday, April 05, 2000 4:48 PM
		To:	HSSG
		Subject:	Re: Interface reality check


		So, now the XGMII has an EMI problem with IDLE? This is the
		I've heard of this. This is also the first that I've heard
		/a/k/r/ can fix such a problem. It seems purely coincidental
		the same pattern used to fix an IDLE EMI problem on XAUI
		happens to be the same pattern used to fix an IDLE EMI
		on the XGMII. It sounds like you're trying to find a
question to
		an answer.

		I must apologize now for the tone of this note. Perhaps this
		simply been a bad day but, for the life of me, I can't see
		this is coming from or what problem you're hoping to solve.


		"Booth, Bradley" wrote:
		> Taking Rich's slides that he sent out last Friday, I did a
couple of tweaks.
		> The concept is that the /A/, /K/ and /R/ that are used for
XAUI are 10-bit
		> symbols.  We can make them correspond to /a/, /k/ and /r/
which are their
		> "byte equivalents."  I put that in quotes, because all
/A/s decode to a
		> single /a/, all /K/s decode to a single /k/ and all /R/s
decode to a single
		> /r/.  The reverse is not true; /a/ is not encoded to a
single /A/ (due to
		> running disparity).  This is the same as in 802.3z.
		> I left the /O/ in, because I think that it might add some
good features in
		> the future.  But /BL/ and /RF/ got turfed.
		> This format would work for, or could be applied to, all
the current
		> proposals we have on the table from SLP, SUPI, WWDM, WIS,
Serial, MAS/PAM,
		> etc.  I tried to keep this at an architectural level, not
an implementation
		> level.  I believe that this architecture should permit the
majority, if not
		> all, of the implementations that get built.
		> Cheers,
		> Brad
		>  <<000405_RScoding.pdf>>
		>                           Name: 000405_RScoding.pdf
		>    000405_RScoding.pdf    Type: Acrobat (application/pdf)
		>                       Encoding: base64

		Benjamin Brown
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		Nortel Networks
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