User guide

TX Multi-Lane Bonding and RX Multi-Lane Deskew Alignment State Machine
The Interlaken configuration sets the enhanced PCS TX and RX FIFOs in Interlaken elastic buffer mode.
In this mode of operation, TX and RX FIFO control and status port signals are provided to the FPGA
fabric. Connect these signals to the MAC layer as required by the protocol. Based on these FIFO status
and control signals, you can implement the multi-lane deskew alignment state machine in the FPGA
fabric to control the transceiver RX FIFO block.
Note: You must also implement the soft bonding logic to control the transceiver TX FIFO block.
TX FIFO Soft Bonding
The MAC layer logic and TX soft bonding logic control the writing of the Interlaken word to the TX FIFO
with tx_enh_data_valid (functions as a TX FIFO write enable) by monitoring the TX FIFO flags
(tx_enh_fifo_full, tx_enh_fifo_pfull, tx_enh_fifo_empty, tx_enh_fifo_pempty,
tx_enh_fifo_cnt, and so forth). On the TX FIFO read side, a read enable is controlled by the frame
generator. If tx_enh_frame_burst_en is asserted high, the frame generator reads data from the TX FIFO.
A TX FIFO pre-fill stage must be implemented to perform the TX channel soft bonding. The following
figure shows the state of the pre-fill process.
2-82
TX Multi-Lane Bonding and RX Multi-Lane Deskew Alignment State Machine
UG-01143
2015.05.11
Altera Corporation
Implementing Protocols in Arria 10 Transceivers
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