Altera Corporation
2–129
October 2007
Stratix II GX Device Handbook, Volume 2
Stratix II GX Transceiver Architecture Overview
Figure 2–102. tx_clockout[0] Feeding TX and RX Phase Compensation FIFOs Across Multiple Transceiver
Blocks
The next example features the dedicated
REFCLK
feeding the
tx_coreclk
and
rx_coreclk
ports as well as supplying the
transceiver with the reference clock (
Figure 2–103
). This requires that the
frequency of the reference clock at the
REFCLK
pin be of the same
frequency as the transceiver output clocks of the associated channels.
Any frequency difference yields corruption of data.
RX Phase
Comp FIFO
TX Phase
Comp FIFO
CRU
RX
TX
TX CLK
Div Block
Channel 3
RX Phase
Comp FIFO
TX Phase
Comp FIFO
CRU
RX
TX
TX CLK
Div Block
Channel 2
RX Phase
Comp FIFO
TX Phase
Comp FIFO
CRU
RX
TX
TX CLK
Div Block
Channel 1
RX Phase
Comp FIFO
TX Phase
Comp FIFO
CRU
RX
TX
TX CLK
Div Block
Channel 0
Tx_clkout[0]
To user
logic
tx_coreclk[3]
rx_coreclk[3]
tx_coreclk[2]
rx_coreclk[2]
tx_coreclk[1]
rx_coreclk[1]
tx_coreclk[0]
rx_coreclk[0]