EP2SGX130GF1508C4 Datasheet, PDF (32/316 Pages) Altera Corporation – Section I. Stratix II GX Device Data Sheet

Transceivers
The rx_syncstatus signal is not available in bit-slipping mode.
Channel Aligner
The channel aligner is available only in XAUI mode and aligns the signals
of all four channels within a transceiver. The channel aligner follows the
IEEE 802.3ae, clause 48 specification for channel bonding.
The channel aligner is a 16-word FIFO buffer with a state machine
controlling the channel bonding process. The state machine looks for an
/A/ (/K28.3/) in each channel, and aligns all the /A/ code groups in the
transceiver. When four columns of /A/ (denoted by //A//) are
detected, the rx_channelaligned signal goes high, signifying that all
the channels in the transceiver have been aligned. The reception of four
consecutive misaligned /A/ code groups restarts the channel alignment
sequence and sends the rx_channelaligned signal low.
Figure 2–19 shows misaligned channels before the channel aligner and
the aligned channels after the channel aligner.
Figure 2–19. Before and After the Channel Aligner
Lane 3
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Lane 1
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Lane 0
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Lane 3
Lane 2
Lane 1
Lane 0
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2–24
Stratix II GX Device Handbook, Volume 1
Altera Corporation
October 2007