Interface Design Of Ethernet And Synchronous Serial Bus

With the rapid development of Internet application technology in this present widespread internet era, Internet users increases rapidly. While computer is used for Internet working, a variety of household appliances, smart instrumentation and devices of data acquisition and control in the industrial production become networking progressively. Currently, the Ethernet protocol has been very used widely in various computer network. After more than 20 years of development, it has become an indispensable part of the underlying Internet link.At the same time, the emerging of new technologies base on Ethernet and various high-end networking devices, Ethernet has become one of the most common network standards. Under the background of an increasingly networked electronic facilities, realizing devices interconnection to share the vast network information resources has become a growing focused concern.To achieve the goal mentioned above, TCP/ IP protocol stack is needed to be embeded in an electronic device to send and receive Ethernet data. However, most of house appliances and industrial control equipment are not equipped with processors and network Interface to handle TCP/IP protocol data directly at present but serial interface in accordance with serial communication standards such as RS232, RS485.As a result, it hinders the process of devices towords to network. So, how to interconnect serial interfaces with network, to achieve remote control of equipment and remote transmission of data, has become a problem needed urgently to be solved.Regarding the issue above, this paper proposes a design that is Ethernet combined with synchronous serial bus interface to achieve mutual conversion between Ethernet and serial data. Its main feature is that the serial data of electronic device access to the designed interface without directly to the Ethernet port for data transmission. Data convertion is also proceeded internally in the designed interface,and it means that the serial data is into Ethernet packets after receving it, and then the encapsulated package is transmitted via the Ethernet port to the network. Conversely,Ethernet package can also be converted into serial data and transmitted to the electronic device.The design is achieved by using SOPC technology. SOPC means System OnProgrammable Chip, which is a special embedded system, and has rich resources of IP cores, programmable logic, short design cycle and low design cost. SOPC combines the respective advantages of SOC, PLD and FPGA, making the designed system more stable and reliable. SOPC is based on the FPGA chip, which integrates the modules such as processor, memory, I/O interfaces required for the design to complete the system's main logic functions. The issue uses Altera Corporation Cyclone II series EP2C8Q208C8 as the main chip and coordinates with Quartus II 12.0 software to achieve the establishment of the entire SOPC system. It can fully complete the hardware design and software design of the system. Hardware design is to call CPU,SDRAM, JTAG, UART and other kernel through Quartus II SOPC Builder development platform, to customize a Ethernet controller chip components according to Avalon bus and to complete corresponding configuration between Ethernet control signal and the Avalon bus signal. Synchronous serial bus module and configuration components can be designed and generated the IP core for the SOPC Builder development platform calls, simultaneously combining with the Ethernet controller chip to achieve the network connection between the PC and the board. Software is designed on Nios II IDE eclipse development platform, including DM9000 A initialization module, TCP/IP protocol data encapsulation and unpacking module,Ethernet data reception and transmission module, to achieve the mutual transformation between Ethernet data and serial data.Finally, the simulation of function modules and the test of system performance.Firstly, synchronous serial bus module is simulated by Modelsim software. And the module is carryed out board-level test. Then, the connecttivity of Ethernet communication interface is tested. Lastly, Hardware configuration system files and software engineering executable files are downloaded respectively to the FPGA chip and configuration chip to carry on system functional test. The test results show that the interface design of Ethernet and synchronous serial bus in this issue can achieves the desired effect, and provides some information and reference for the research of Ethernet Interconnect with the electronic communication devices.