Virtex 4 FX Sonet Alignment

Is there anybody in this group who has experience with V4FX MGT Sonet
Alignment?

The documentation is rather short on details. The interaction of the
two alignment stages is not clear to me at all.
What we see is that we get a comma detect signaled and the output data
stream is correctly aligned.
As a reaction on that we turn off ENPCOMMAALIGN and ENMCOMMAALIGN.

But nevertheless the MGT keeps realigning on any new occurence of the
comma pattern.
(only the bits are shifted around, there is no new comma detect
signaled.)

What am I missing?

Kolja Sulimma

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