18.104.22.168. Block Synchronizer
The block synchronizer determines the block boundary of a 66-bit word in the case of the 10GBASE-R protocol or a 67-bit word in the case of the Interlaken protocol. The incoming data stream is slipped one bit at a time until a valid synchronization header (bits 65 and 66) is detected in the received data stream. After the predefined number of synchronization headers (as required by the protocol specification) is detected, the block synchronizer asserts rx_enh_blk_lock (block lock status signal) to other receiver PCS blocks down the receiver datapath and to the FPGA fabric.