This signal indicates whether an Interlaken protocol formatting error or a CRC24 error occurred in a Control Word. When operating in packet mode, this signal also indicates missing SOP or missing EOP errors. A value of 1 indicates an error occurred. Whenever this signal is asserted, all open packets are marked as containing errors as specified by the Interlaken Protocol Definition, Revision 1.2 . By definition, there is no mechanism provided by Interlaken to associate a CRC24 or similar error with individual packets.
This signal is asserted for one clock period each time an error is detected.