The Design And Implementation Of The Multifunctional Gateway For Embedded Marine Communication

With the continuous development of automatic control and computer technology, the level of ship automation is gradually improving. In order to solve the data exchange between control network and information communication network, as well as the real-time control, the gateway of ship has emerged as the times require. It is a part of the ship communication system. The Ethernet which is most widely used is the upper network of the gateway of ship, the lower network is often the industrial field bus, and CAN bus is widely used now. The communication between the Ethernet of the host computer and the CAN bus network in the ship control communication network is realized, the bottom monitoring points are connected with the upper monitoring network, the field data of the monitoring system and the alarm information can be transmitted to the main control platform of the ship, which provides a convenient way for the monitoring and diagnosis of the ship.Firstly, according to "Shipbuilding Industry Standards of the People’s Republic of China", the ship electronic frame of DSP307 and the related references, the overall design scheme of the gateway system and the function modules of the system are determined. Due to the different types of ships and different communication requirements, a gateway hardware based on AT91SAM9X25 processor is designed in this paper, which is suitable for large or larger ships. And a gateway hardware based on i.MX287 processor is designed which is suitable for medium and small ships. At the same time, the dual redundancy software and the interface function design are realized. In addition, this paper also implements the kernel configuration and driver transplantation in the environment of Linux.According to the overall design scheme, the circuit is designed in Altium Designer environment. In the gateway which is based on AT91SAM9X25 processor, CAN transceiver uses the chip of TJA1050, Ethernet controller uses the chip of DM9161AEP. It mainly includes two CAN bus function circuits, two Ethernet function circuits, serial port function circuit, USB circuit,power circuit and so on. In the gateway which is based on AT91SAM9X25 processor, CAN transceiver uses the chip of SN65HVD234, Ethernet controller uses the chip of LAN8720A. This gateway consists of the reset circuit, power circuit, USB interface circuit, JTAG interface circuit, dual CAN bus circuits, dual Ethernet circuits, serial circuit and LCD display circuit. At the same time, the Qt Creator software platform which is under the Linux operating system is used to design and implement the displayed interface, and using C++ programming language to achieve the communication program in the background.Finally, by testing the hardware, its performance meets the indicators of requirement. By testing the software function, the function of the system is stable.