Design of Embedded Ethernet Controller Based on B/S Mode
|Course||Signal and Information Processing|
|Keywords||B/S mode Embedded Ethernet LPC1768 micro controller TCP/IP|
Traditional control systems often use the communication modes such as RS232, RS485 with low transmission efficiency, short transmission disance and poor anti-interference ability, which are difficult to meet the requirements of real-time high-speed data communications. However, the control networks based on Ethernet technology are consistent with the trend of control system networks’development. Its emergence marks the beginning of another new generation in the field of industrial control technology, and will exert an impact on the development of this field definitely. The Ethernet technology is one of the most popular and widely used communication technologies currently. It has a number of advantages such as low cost, high speed, easy to organize networks and has various transmitting media to use. What’s more, it’s easy to be connected to the Internet. With the rapid development of IT technology and emergence of the internet of things(IOT), to realize the information exchange, most of the embedded devices needed to be connected to Internet emergently to transmit information anywhere flexibly. Therefore, it has become an important rese irch issue and concerning point for the finite embedded devices to realize networking.The B/S (Browser/Server) mode is developed from the traditional C/S (Client/ Server) mode, and its user interface is realized by web broswer totally. Thus it does not need complex and special client software, as well as maintenance. A part of business logic is realized on the client, but the main business logic is realized on the server, lightening the client computer’s loads greatly, reducing the cost of maintenance and upgrades of systems, decreasing user’s overall costs. In addition, the system’s scalability and extensibility is enhanced, which ensures the timeliness, accuracy and security of data to the full extent.Combining with the current development, the design of embedded Ethernet controller based on B/S mode is proposed in this paper. Fistly, the design of hardware platform of the Ethernet controller is introduced, which is mainly realized by the micro controller LPC1768 and PHY chip DP83848C. On that basis, the paper gives the analysis and transplant process of RTOS uC/OS-II, embedded TCP/IP protocol stack LwIP respectively. And then, the development process of driver program of network interface is also showed. Finally, on the designed platform of hardware and software, the embedded web server is realized, and the design of contoller’s user page is worked out. What’s more, the session procedure between user page and web server is analyzed.