Research on the detecting system of distributed nodes based on RS-485 bus

In order to achieve the largest number of distributed network nodes and increase the communication security of network system in the conditions of long-range and high data rate, we introduce registration mechanism of communication nodes with distributed network nodes as the research object in this paper. With the application of single chip microcomputer (SCM) technology, we designed and implemented network system based on RS-485 bus, analysis several factors that affect the RS-485 network, explained the overall structure of the system and designed strictly closed communication protocols. 3000 communication nodes address were simulated by using 200 nodes. The registration of the nodes was comprehensive tested, and the distribution of 3000 nodes´ pseudorandom register codes was statistics. In the conditions of using RS-485 bus drivers with 256 maximal nominal value of the node number, the distance of transmission cable within 200 m and baud rate of 115200bps, the result shows that the distributed network testing system is stable, network communication is reliable and better results are achieved.