| In the field of integrated circuit design,with the increasing needs on the function of the chip and the decreasing of the chip size,many designers have put forward the concept named "system of on a chip"(So C).It integrated a lot of the function on a chip,and quickly occupied the whole market of chip design because of its high level of integration,the characteristics of less cables,simple authentication process.In network transmission solution,the Ethernet is the most useful transmission medium with highest network use frequency、widely application scope and biggest influence in human life.Therefore,the Ethernet MAC module integrated in So C chip for data transmission has also been used by many designers.However,with the update of the network,the speed of data transmition has increased a lot.Neither 10M/100 M speed Ethernet MAC,nor the design only concerned tranditional function of 1000 M speed Ethernet MAC can not match the need of the cumstomers.Because of these questions,the papper has designed a new 1000 M Ethernet MAC based on DMA.The topic of this paper is derived from a specific purpose of So C system chip design projects.The So C integration accords with Ethernet transmission protocol,and meet 10M/100M/1000 M speed of Ethernet MAC controller IP core.There are three aspects of this papper: The study of the fundamental function modules of the Ethernet,1000 M Ethernet MAC design based on the DMA,and the functional verification of this design.Firstly,based on the study of the Ethernet transmission protocol,papper analyzes the realization of the Ethernet MAC point and basic function of logic.Summarize the characteristics of the traditional Ethernet,and the three optimization scheme.Secondly,according to the research and thinking of Ethernet MAC basic function point transfer protocol,papper has design not only the basic functional modules in the chip for Ethernet MAC,but three function modules named flow-control module,frame-state-monitoring module,and GPCS module.Thirdly,according to the functions of the design,the papper has build the simulation environment,and proposed more than 60 items under test function concerned the right/wrong situation.Also,papper has done the module and system tests using NC-Sim..Finally,by the way of reviewing tests,papper has decreased the probabilities of accidental error,and completed the work. |
