Design Of Industrial Ethernet Application System

With the development of control, computer, communication and network, industrial network has been developed from analog-signal-based system to Fieldbus system which is digital, intelligent and distributed structure and this has brought a great revolution to industry automation. However, multiprotocol and incompatibility among Fieldbus standards has not only hindered its further development, but also caused problem that system and information integration is facing many difficulties. Ethernet, the most popular Local Area Network structure, has many obvious advantages such as open, cost-effective, supported by popular hardware and software. In addition, the rapid development of information technology such as Internet requires the ability of seamless integration between management layer and field control layer and provides an open infrastructure, which makes it possible that to use Ethernet in the industrial network. Therefore, it is quite necessary to make scientific researches on industrial Ethernet application system.Firstly, this paper introduces the status quo of embedded Ethernet node and expatiates on several Internet connection modes which are widely used at present. Then on the basis of researching the key technology of Ethernet communication, several typical industrial Ethernet overall schemes are discussed mainly. According to the schemes, the protocols to support every type of industrial Ethernet system are analyzed, and a certain industrial Ethernet application system being realized recently is confirmed at last.Secondly, a design method based on C8051F023 microcontroller is provided in this dissertation. We focus on the functional explanation and the description of every part of the Ethernet node. The Ethernet node designed and implemented in this dissertation has several advantages, such as low costs, small volume, high speed, good currency and good convenience. It is an excellent method to remote-monitor, remote-control and remote-diagnose systems, and it can be used in a lot of fields such as Information Appliance, Industrial Automation, Smart Instrument and Sensor Technique. So, it will have a wonderful applied perspective.Communication protocol is the key to realize the network communications. By analyzing the TCP/IP protocols deeply, this dissertation simplifies the TCP/IP stack and only implements ARP, IP, ICMP and HTTP protocols. Based on it, the network monitor project based on browser/server mode in industrial control process is researched in this paper and the basic Web server function also has been realized. Besides, this paper also defines a simplified application protocol and programs the software on PC, and realizes the server/client mode.At last, the Ethernet system is applied in the environment of my lab. Over it, every key point in the process of design is tested.