Design And Implementation Of Modbus/TCP Gateway Based On Embedded Linux

With the development of modern enterprise information, the seamlessly connection between enterprise-level network management network and control devices becomes more and more important. Live instrumentation processed on-site information, timely monitoring, management to superior network access and control, play an important role in the production and operation of a modern enterprise.Currently, field bus technology based on the underlying control network has gained widespread application. Coexistence of various field bus standards which are not compatible has been plaguing the industry. The Industrial Ethernet applied to control network has become a hot spot and future development trends. How to make this kind of network structure and industrial Ethernet technology combine to achieve the underlying production is tightly integrated with the upper management, which is a hot research topic.Considering the low power consumption and rich hardware resources, this paper designs an embedded LINUX gateway with hardware architecture by using Arm926ejs industrial chip LPC3250. Firstly, the hardware uses the core board and backplane design to ensure maintainability, stability and subsequent expansion of the embedded gateway function. This design not only shortens the development period, but also makes its hierarchy more clearly. Secondly, at the system level, this paper uses an embedded LINUX operating system to transplant Uboot, and finish LINUX kernel configuration. Application software layer is mainly based on C/S model with the data frame embedded Modbus TCP frame, achieving a stable field bus and industrial Ethernet devices.The stability, reliability test of the designed gateway is made in experimental environment. And Schneider PLC is used for testing of PLC IO port. The test results show that the proposed gateway can achieve data forwarding and protocol conversion effectively.