Study And Design Of Embedded Serial Server

With the fast development of electric equipments and Internet, it has become top necessity among world companies to have all devices connected to network. In order to win in competition, large numbers of dispersive serial devices without network connection function need accesses to Internet. In this way, through data transfer and management via Internet, automatic management, intelligent control and so on can be realized. Instead of huge investment to change or upgrade existing serial equipments, through embedded Serial-Ethernet Server, serial data stream transfer via TCP/IP provides a way for existing serial equipments to obtain network connection function. Thereby, the restriction in transfer distance and reliability of serial communication will be avoided effectively.The Serial-Ethernet Server designed in this dissertation adopts ARM7TDMI as embedded processor and uClinux as operating system. It transforms data coming from RS-232 interface into IP format, and then sends traditional serial data to Internet, or in the opposite way. Serial-Ethernet Server realizes data estimation, transformation and transfer between RS-232 serial port and network interface. The data streams from serial equipment will be processed, transformed into data frames which can be transferred in internet;also the data frames from network interface will be checked, transformed into serial data and sent to serial equipment.The main achievements could be summarized as follows:1. Proposed the holistic development scheme for Serial-Ethernet Server based on the analysis of both hardware and software platforms.2. Designed server work mode and client work mode respectively for different network connections environments, with the function of system parameter online setup.3. Realized bidirectional communication between serial equipment and remote host computer, adopted special data transfer strategy to insure data transfer accuracy and timing.4. Accomplished appropriate software platform for this Serial-Ethernet Server through modification and compiling of uClinux kernel and file system.