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Chapter 2: Core Architecture

Table 2-1:GMII Interface Signal Pinout

Signal

Direction

Description

 

 

 

gmii_txd[7:0]1

Input

GMII Transmit data from MAC.

gmii_tx_en1

Input

GMII Transmit control signal from MAC.

gmii_tx_er1

Input

GMII Transmit control signal from MAC.

gmii_rxd[7:0]2

Output

GMII Received data to MAC.

gmii_rx_dv2

Output

GMII Received control signal to MAC.

gmii_rx_er2

Output

GMII Received control signal to MAC.

gmii_isolate2

Output

IOB Tri-state control for GMII Isolation. Only of use

 

 

when implementing an External GMII as illustrated by

 

 

the example design HDL.

 

 

 

1.When the Transmitter Elastic Buffer is present these signals are synchronous to gmii_tx_clk. When the Transmitter Elastic Buffer is omitted, see Note 2.

2.These signals are synchronous to the core’s internal 125 MHz reference clock. This is userclk2 when the core is used with the RocketIO transceiver; gtx_clk when the core is used with TBI.

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Ethernet 1000BASE-X PCS/PMA or SGMII v9.1

 

 

UG155 March 24, 2008

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Xilinx manual Ethernet 1000BASE-X PCS/PMA or Sgmii