Altera Triple Speed Ethernet MegaCore Function - Manual (Page 70)

When the PHY is in power-down state, the PCS function is in reset and any activities on the GMII transmit
and the TBI receive interfaces are ignored. The management interface remains active and responds to
management transactions from the MAC layer device.
Figure 4-22: Power-Down
MDIO
Slave
powerdown
Control
Powerdown Control
(Technology Specific)
1000BASE-X PCS
Power-Down in PCS Variations with Embedded PMA
In PCS variations with embedded PMA targeting devices with GX transceivers, the power-down signal is
internally connected to the power-down of the GX transceiver. In these devices, the power-down functionality
is shared across quad-port transceiver blocks. Ethernet designs must share a common
gbx_pwrdn_in signal
to use the same quad-port transceiver block.
For designs targeting devices other than Stratix V, you can export the power-down signals to implement
your own power-down logic to efficiently use the transceivers within a particular transceiver quad. Turn on
the Export transceiver powerdown signal parameter to export the signals.
Figure 4-23: Power-Down with Export Transceiver Power-Down Signal
PMA
POWERDOWN
CONTROL
pcs_pwrdn_out
gxb_pwrdn_in
1000BASE-X PCS
1000BASE-X/SGMII PCS Reset
A hardware reset resets all logic synchronized to the respective clock domains whereas a software reset only
resets the PCS state machines, comma detection function, and 8B10B encoder and decoder. To trigger a
hardware reset on the PCS, assert the respective reset signals:
reset_reg_clk
,
reset_tx_clk
, and
reset_rx_clk
. To trigger a software reset, set the
RESET
bit in the
control
register to 1.
In PCS variations with embedded PMA, assert the respective reset signals or the power-down signal to trigger
a hardware reset. You must assert the
reset signal subsequent to asserting the reset_rx_clk , reset_tx_clk ,
or
gbx_pwrdn_in
signal. The reset sequence is also initiated when the active-low
rx_freqlocked
signal goes
low.
Functional Description Altera Corporation
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UG-01008
Power-Down in PCS Variations with Embedded PMA 4-34
2014.06.30