thanks a lot to Wolfgang Grandegger. He signaled me the patch of ep9315 in
this mailing list.
it's ok and work correctly, it has a jitter, ( it's different from the word
'latency', i can't measure the latency actually ) of about +/-100us in
user-space and 60us +/- in kernel-space respect the *hypothetic *period.
I try for other time this patch but actually it seems OK.
Here is the previous link that indicates an ipipe patch.
Xenomai-core mailing list