Building a wireless sensor network with use of RFM 12 modules - data exchange between nodes

IEEE 802.15.4 standard defines Physical (PHY) and Wireless Medium Access Control (MAC) layers for wireless sensor networks (WSN). In recent years, many types of wireless sensor networks have been developed based on this standard. Currently, probably the most popular implementation of the mentioned standard are wireless ZigBee networks. Moreover, ZigBee provides functions normally attributed to the higher layers of network protocol stack. Among those the most important functions are: routing of data, data encryption and providing redundancy connections between devices in the network. We present a slightly different approach to the construction of wireless sensor networks. This is the beginning of series of papers about implementation of the IEEE 802.15.4 standard and the previously mentioned expansion functions in the network, built with RFM wireless communication modules and ATmega processors. This paper describes the basics of compiling wireless connection and data transmission with using RFM modules. In addition, blocking and non-blocking types of connections between radio modules and ways to connect RFM modules with ATmega processors are described.