摘要摘要随着信息技术的快速发展，以太网嵌入式设备的应用越来越广泛。为了让以太网各设备之间能公平有效地共享通信媒介，对以太网MAC层数据处理系统的研究显得尤为重要。为此，本文首先分析了以太网及其相关协议的基本内涵，解剖了以太网MAC层通信机制、帧的特性与格式、PHY接口协议、ARP协议以及I2C协议。同时通过对FPGA芯片的了解，确定了基于88E1111芯片和XC3S400FPGA芯片相结合的系统设计方案，支持1000Base-T标准以太网的接入，完成了系统的硬件电路设计。系统设计中，88E1111完成PHY层数据的处理，FPGA则完成MAC层数据的处理，主要包含接收MAC数据帧的校验和解封、待发送数据帧的封装、MAC地址滤波、IP数据包的提取、ARP地址映射等，是系统的核心。在FPGA设计中，遵循自上而下的设计思想，对顶层模块以及PHY接口、MAC核心处理、用户配置、用户数据各功能子模块依次进行设计。关键词：以太网MAC层FPGAABSTRACTABSTRACTWiththerapiddevelopmentofIT,theembeddeddevicesofaccessingtoEthernetareusedmoreandmorewidely.Inordertomakeeachdeviceenjoyafairandeffectivesharedcommunicationsmedium,itisparticularlyimportanttoresearchthedataprocessingsystemoftheEthernetMAClayer.Tothisend,itisfirstlydonetoanalyzethebasicconnotationofEthernetandtherelatedagreements,andtodissectthecommunicationmechanismsoftheEthernetMAClayer,thecharacteristicsandformatoftheframe,thePHYinterfaceprotocol,theARPprotocol,I2Cprotocolinthepaper.AccordingtothecharacteristicsandworkingprincipleoftheFPGAchip,thesystemdesign,whichsupportstheaccessingofthe1000Base-TEthernet,isdeterminedbasedonthecombinationofthe88E1111PHYchipandXC3S400-4fg456CFPGAchipofXilinx.ThenthehardwarecircuitdesignisaccomplishedbytheCadencedevelopmenttool.Inthissystem,88E1111andFPGArespectivelycompletesthedataprocessingofPHYlayerandthedataprocessingoftheMAClayer,whichmainlyconsistsofthecalibrationanddearchiveofthereceivingdataframes,theencapsulationofthedataframes,theMACaddressfiltering,theextractionoftheIPpacket,TheARPaddressmapping,andsoon.SoFPGAisthecoreofthesystem.Followingthetop-downdesignconception,thedesignofFPGAsuccessivelyincludesthetop-levelmodule,andthesubmoduleofthePHYinterface,theMACcoreprocessing,theuserconfiguration,theuserdatainterface.Keywords:EthernettheMAClayerFPGA目录i目录第一章绪论.........................................................................................................11.1研究背景及意义......................................................................................11.2国内外研究现状......................................................................................21.3论文内容和论文组织结构安排..............................................................3第二章千兆以太网理论基础.............................................................................52.1千兆以太网标准......................................................................................52.2介质访问控制（MAC）........................................................................72.2.1半双工MAC...............................................................................72.2.2全双工MAC...............................................................................92.3介质无关接口（MII）.........................................................................102.3.1GMII接口信号定义..................................................................112.3.2GMII接口时序特性..................................................................142.3.3GMII的管理MDIO接口...........................................
