The access nodes from the bottom realize the connection of sensors of different types,and the upper central computer uses Ethernet for high-capacity data transmission,while composite nodes on the middle layer burden the functions of protocol conversion and logical layer data fusion.Sensor network nodes developed by this subject have the functions of both composite nodes and access nodes,and occupy an important position in the whole sensor network system.Considering the development costs and system performance,we have designed the hardware and software of sensor network nodes.The development and debugging of sensor network nodes include the followings.First,multi-task management and scheduling by the system are achieved by transplanting uC/OS-Ⅱreal-time operating system into the TMS320F2812.Second,system implements the acquisition of traffic status basic information by using information acquisition circuit.Third,system implements the bidirectional conversion of CAN fieldbus and Ethernet by the design of protocol conversion(CAN-TCP/IP) module.
