SDRAM在EOS中以太网口的应用

在EOS(Ethernet over SDH)应用设计中，以太网侧收到的媒体访问控制(MAC)帧要先存储再由成帧器将数据取走。文章介绍了其实现过程，采用同步动态随机存储器(SDRAM)作为片外的存储器，利用SDRAM的特征，发挥其高速、大容量的优点，可确保专用集成电路(ASIC)芯片上缓存面积减少，并可将以太网数据准确映射到SDH传送网中。该设计已在现场可编程门阵列(FPGA)上得到验证，并通过网络分析仪进行了测试。

Application of SDRAM in Ethernet port of EOS

In the design of EOS, the MAC frames received by Ethernet are stored firstly and then removed by eneapsulation engine. This paper describes the realization process in which the SDRAM is used as and off-chip memory.Utilizing the features of SDRAM, especially its advantages of high-speed and large capacity, the buffer area on ASIC chip can be certainly reduced and the Ethernet data can be accurately mapped into the SDH transport network. The design has been verified on FPGA and passed the IP network analyzer test.