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Re: bit ordering on XSBI vs SFI-4

In a message dated 3/26/01 12:28:50 PM Pacific Standard Time,
Jonathan.Thatcher@xxxxxxxxxxxxxxxxxxxx writes:

Subj: RE: bit ordering on XSBI vs SFI-4
Date: 3/26/01 12:28:50 PM Pacific Standard Time
From:    Jonathan.Thatcher@xxxxxxxxxxxxxxxxxxxx (Jonathan Thatcher)
Sender:    owner-stds-802-3-hssg@xxxxxxxx
To:    stds-802-3-hssg@xxxxxxxx

Before offering any opinion on this, I would like to know what impact there
would be on measurement and test equipment, if any.

Clearly, a piece of equipment expecting a serial PRBS pattern would need the
bits in a specific order. No?


Hello All,

Let me state again that any changes (if any) would only be in relabeling and
is purely a logical construct. There was/is neven intention to actually have
Ethernet packets sending bit stream data out on a serial link in a MSB first
manner. If Pat (clause 49) or anyone else does see this as becoming the case
then I would back off from this effort and just leave things as is. This
leaves the
user (customers of modules makers) to be careful in knowing which bit is
sent out first on the link. Leaving things as is OR relabeling the XSBI to
MSB should
never stop implementers. The serial PMA is a "dumb" device ...

Just a try here to make a simple suggestion ...

If I relabeled the XSBI to have MSB transmitted first then Pat coming out
from her clause could possible reword saying that the LSB should be mapped to
the MSB of the XSBI in the case of a serial link.

Justin Chang
Quake Technologies, Inc.
2880 Zanker Road, Suite 104
San Jose, CA 95134
Tel: 408-922-6888 x108
Fax: 408-922-6827
email: justin@xxxxxxxxxxxxx