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Altera_Forum's avatar
Altera_Forum
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16 years ago

max CID length for transceivers

Does anyone know what is the max CID (consecutive identical digits) length the CDR can tolerate before it loses its lock on the incoming data? I've been reading through the docs for the Stratix IV t...
Altera_Forum's avatar
Altera_Forum
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16 years ago

Thanks. I had seen the information on the programmable run length violation detection before, but it is located in the word aligner block and doesn't seem to have anything to do with the CDR. Plus, if I'm not using the word aligner I'm not sure I can use this decoder. I may be wrong, but at least the way it's described I don't think this is the same as the max CID run length the CDR can tolerate before it loses the lock on the data.

I did find in the datasheet (not the handbook) a single line listing the run length maximum of 200 UI. There is no explanation or further description of this line, but maybe this is the number I was looking for.

Thanks for your help!