| CAN-BUS is a serial communication protocol, being widely used in industrial control system for high reliability, high bit rate, strong anti-interference and flexible configuration. Since the good features, the National Maritime Electronics Association (NMEA) has introduced a new standard (NMEA2000) for data communications among shipboard electronic devices. The communication process and the method for realizing the NMEA2000 network are introduced in this paper.The NMEA2000 is a CAN-based network which permits inexpensive communication among shipboard electronic device. On the NMEA2000 network, data, commands and status all share the same cable at speeds 26 times greater than the NMEA0183 serial interface, which plays an important role in nowadays. The intelligence CAN nodes make up with SJA1000 and 82C250. And then, the process of sending and receiving message, the principle of "hot plug and play" is introduced. At last, a test window is designed for debugging the NMEA2000 network. The test window show the message transmitted on the network. And can send data frame and remote frame to the network. Finally a mini NMEA2000 network with CAN nodes is made and the function of sending and receiving message are realized on the network.NMEA2000 is a low-cost serial data network operating at 250kbps utilizing the CAN integrated circuit. NMEA2000 defines standard data formats and definitions, and provides extensive network management rules for identifying nodes on the network, sending commands to device, and requesting data. |
