03-23-2009 10:36 PM
03-24-2009 08:23 PM
ok, found the answer from UG196, but not happy with it. I was expecting a signal directly from GTP to determine CDR is locked.
Page 167, Normally, CDR lock is detected by measuring the quality of incoming data. Methods for detecting CDR lock include: Finding known data in the incoming data stream (for example, commas or A1/A2, etc...
I think that is an incorrect way to determine CDR is locked. Easily, TX far-end point can be sending A1/A2 wrongly, but that doesn't mean CDR is not locked.
About the documentation, I didn't find this information before because is on the RX phase alignment part. I think that information should be under RX clock data recovery part.
Any thoughts about this?