4.2.4. PMA Direct 25 Gbps x 4 (FEC Off)
This use case does not include FEC; therefore, there is no need for clock sharing
between the four 25-Gbps channels.
For FIFO in Phase Compensation mode, connect
tx_clkout
(402.83 MHz) to
tx_coreclkin
and connect
rx_clkout
(402.83 MHz) to
rx_coreclkin
. If you use
any other source for
tx_coreclkin
or
rx_coreclkin
, make sure
tx_coreclkin
and
rx_coreclkin
have 0 PPM difference with the
tx_clkout
and
rx_clkout
,
respectively. This example assumes that TX and RX Double Width transfer is enabled.
Figure 55.
PMA Direct 25 Gbps x 4 (FEC Off)
E-Tile Native PHY IP
TX PMA
25.78125 Gbps
RX PMA
E-Tile FIFO
E-Tile FIFO
EMIB
Native PHY IP
Core Interface
tx_clkout
402.83 MHz
TX Data
tx_coreclkin
rx_coreclkin
rx_clkout
402.83 MHz
RX Data
TX Core FIFO
TX Core FIFO
TX Core FIFO
TX Core FIFO
TX Core FIFO
TX Core FIFO
XCVR
Interface
XCVR
Interface
/2
/2
CH3
E-Tile Native PHY IP
TX PMA
25.78125 Gbps
RX PMA
E-Tile FIFO
E-Tile FIFO
EMIB
tx_clkout
402.83 MHz
TX Data
tx_coreclkin
rx_coreclkin
rx_clkout
402.83 MHz
RX Data
XCVR
Interface
XCVR
Interface
/2
/2
CH2
E-Tile Native PHY IP
TX PMA
25.78125 Gbps
RX PMA
E-Tile FIFO
E-Tile FIFO
EMIB
tx_clkout
402.83 MHz
TX Data
tx_coreclkin
rx_coreclkin
rx_clkout
402.83 MHz
RX Data
XCVR
Interface
XCVR
Interface
/2
/2
CH0
Legend:
TX PMA generated parallel clock (line rate / PMA interface width)
TX PMA generated parallel clock div by 2
RX PMA generated parallel clock div by 2
RX PMA generated parallel clock (line rate / PMA interface width)
4. Clock Network
UG-20056 | 2019.02.04
Intel
®
Stratix
®
10 E-Tile Transceiver PHY User Guide
94