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Re: 64B66B bit ordering


That's what I get for putting out a mail message at 11:00 pm
before going to bed. You are correct in regards to the Type
byte. I've attached a corrected copy for those who want a
pretty picture :)


"Bharadwaj (Birdy) Amrutur" wrote:
> Ben,
> Your suggestion works, except for the bit ordering of the
> type byte. The type byte should also be indicated bit
> reversed to be consistent with the rest of the fields.
> type byte "0x1e" -> 01111000. (I think you had it bit
> reversed within each nibble wihout exchanging the nibbles).
> Birdy
> >Birdy,
> >
> >I tend to like the first proposal but I can follow the
> >second. Also, I think the second is the one that matches
> >most closely the mapping you have in the presentation.
> >Changing now would probably cause more confusion.
> >
> >More confusing is maping the Z fields into the frame.
> >You need to be very explicit in showing exactly how
> >the bits of each Z field maps into the frame. My suggestion
> >would be to pick a method for mapping the D fields into
> >the frame then show exactly how the Z fields map into
> >the frame in the exact same format.
> >
> >Your "Code Summary" slide is a great picture of how the
> >D frames and the Z frames map to each other. What's missing
> >is exactly the order of the bits. I've attached a picture.
> >See what you think.
> >
> >Ben

Benjamin Brown
Router Products Division
Nortel Networks
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