Configurable Channel Bonding (Lane Deskew); Overview - Xilinx Virtex-5 RocketIO GTP User Manual

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Configurable Channel Bonding (Lane Deskew)

Overview

The RX elastic buffer can also be used for channel bonding. Channel bonding cancels out
the skew between GTP lanes by using the RX elastic buffer as a variable latency block. The
transmitter sends a pattern simultaneously on all lanes, which the channel bonding circuit
uses to set the latency for each lane so that data is presented without skew at the FPGA RX
interface.
Figure 7-28
Virtex-5 RocketIO GTP Transceiver User Guide
UG196 (v1.3) May 25, 2007
shows a conceptual view of channel bonding.
RX Data is Two Clock Cycles
Ahead of GTP1 Data
RX Data is Two Clock Cycles
Behind GTP0 Data
Figure 7-28: Channel Bonding Conceptual View
www.xilinx.com
Configurable Channel Bonding (Lane Deskew)
64 Element Elastic Buffer
(Set to Four Cycles of Latency by
Channel Bonding Controller)
64 Element Elastic Buffer
(Set to Two Cycles of Latency by
Channel Bonding Controller)
Deskewed Data
GTP0 (Master)
Deskewed Data
GTP1 (Slave)
UG196_c7_25_092606
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