R

Chapter 2: Core Architecture

 

LogiCORE Ethernet 1000BASE-X PCS/PMA or SGMII Core

 

 

 

 

PCS Transmit Engine

 

 

 

GMII

GMII Block

Optional

RocketIO I/F Block

RocketIO Transeiver

To PMD

to MAC

Auto-Negotiation

Sublayer

 

 

 

 

 

 

 

PCS Receive Engine

 

 

 

 

 

and Synchronization

 

 

 

MDIO

 

Optional PCS

 

 

 

 

Management

 

 

 

Interface

 

 

 

 

 

 

 

 

Figure 2-1:Functional Block Diagram Using RocketIO Transceiver

GMII Block

A client-side GMII is provided with the core, which can be used as an internal interface for connection to an embedded Media Access Controller (MAC) or other custom logic. Alternatively, the GMII may be routed to device IOBs to provide an external (off chip) GMII.

PCS Transmit Engine

The PCS transmit engine converts the GMII data octets into a sequence of ordered sets by implementing the state diagrams of IEEE 802.3 (figures 36-5 and 36-6). See Appendix D, “1000BASE-X State Machines.”

PCS Receive Engine and Synchronization

The synchronization process implements the state diagram of IEEE 802.3 (figure 36-9). The PCS receive engine converts the sequence of ordered sets to GMII data octets by implementing the state diagrams of IEEE 802.3 (figures 36-7a and 36-7b). See Appendix D, “1000BASE-X State Machines.”

Optional Auto-Negotiation Block

IEEE 802.3 clause 37 describes the 1000BASE-X Auto-Negotiation function that allows a device to advertise the modes of operation that it supports to a device at the remote end of a link segment (link partner), and to detect corresponding operational modes that the link partner may be advertising.

Auto-Negotiation is controlled and monitored through the PCS Management Registers. See Chapter 10, “Auto-Negotiation.”

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

UG155 March 24, 2008

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Xilinx 1000BASE-X Gmii Block, PCS Transmit Engine, PCS Receive Engine and Synchronization, Optional Auto-Negotiation Block