ZigBee technology, as the most commonly used wireless technology in the field of IoT, has been widely used in smart homes, farmland intelligent management, and energy-saving applications. In order to facilitate the use of ZigBee for project development, we will share the knowledge of the ZigBee protocol stack and networking today. Figure 1 ZigBee wireless network application The ZigBee protocol stack can be divided into four layers: physical layer (PHY), media access control layer (MAC), network layer (NWK), and application layer (APL). As shown in Figure 2, the pink part is defined by the IEEE standard, the light blue part is specified by the ZigBee Alliance, and the yellow part is defined by the equipment manufacturer. Figure 2 ZigBee protocol stack icon The physical layer and MAC layer of the ZigBee protocol stack are defined in the IEEE802.5.14 standard. The PHY layer (physical layer) specifies the frequency bands used and the wireless transmission technologies such as coding, modulation, spread spectrum, and frequency modulation. The main role of the MAC layer defines the access control mechanism of the wireless channel, which is to specify the rules according to which devices use the channels in turn; if there is no MAC layer protocol, if there are more than one node and there is no regular receiving and sending mechanism, signal collision will occur. Transfer data normally. The ZigBee protocol stack defines the network layer based on the 802.15.4 protocol. The main role of the network layer is to be responsible for the connection and disconnection of devices, the security mechanisms used in the transmission of frame data, route discovery and maintenance. To put it simply, it is to ensure the data transmission between the equipment network and network nodes. The standard ZigBee network protocol includes coordinators, routers, and end nodes, and the establishment of a ZigBee network requires only a router or terminal node, in addition to the coordinators that it must have. Before the standard ZigBee Pro network communication is started, if a routing table for storing the jump path is not established, the node cannot communicate with the network. Similarly, it needs to periodically send a network packet to check whether the node is abnormal. It can be seen that ZigBee Pro not only starts slowly but also uses a large amount of bandwidth to send network packets at regular intervals. Figure 3 ZigBee Pro Networking Diagram If any node on the network has peer-to-peer data transmission functions, and no coordinator is required to manage the network, any node in the network can actively transmit data. In this way, users do not need to care about the specific network structure, and it is obviously more convenient to use. And construction workers do not need to understand the relevant configuration. Based on this, ZLG Zhiyuan Electronics has developed a FsatZigBee transparent peer-to-peer network protocol based on the ZigBee protocol stack with the deep accumulation of wireless technologies and rich practical experience. Figure 4 Zhiyuan Electronic FastZigBee Networking Diagram Its characteristic advantages are as follows: 1, start zero delay: FastZigBee node power-on without networking waiting, can be directly based on the configuration information data output, a small wake-up start networking time and power consumption; 2. Large node capacity: FastZigBee adopts 16-bit short address management. Under the polling mechanism, the theoretical node capacity is up to 65,535. 3, completely transparent: FastZigBee transparent transmission, users can freely create a proprietary protocol format, not limited to a fixed third-party agreement; 4. No need for secondary development: In the embedded module of FastZigBee networking protocol, it can be configured with supporting software or AT configuration command to facilitate fast networking communication. Figure 5 FastZigBee Peer-to-Peer and Multipoint Communication Diagram Under normal circumstances, when the number of nodes is small, we can quickly complete the configuration and put into use through the matching configuration tools. When the number of nodes is a certain degree, if it is still one node to configure, obviously it is very troublesome, then you can use the AT command to control the FsatZigBee module to enter the ad hoc network mode, and quickly realize on-site dynamic networking. Figure 6 Host module self-organizing process Figure 7 Slave module ad hoc network icon If you need to update the site later, you can change the number and layout of the nodes in the LAN. You can also use the command to control the host module to reacquire the network parameters. The slave module exits the previously added network and enters the ad hoc network again to quickly complete the new network setup. . Figure 8 Host Regains Network Parameters Figure 9 Slave module exit operation ZLG Zhiyuan Electronics' AW516X series modules based on NXP JN516X wireless microcontrollers support ad hoc network functions. The AW516X series greatly simplifies the complex development process of wireless products and directly provides multiple user-configurable AD, IO and PWM interfaces. Your product can be quickly put into the market at a lower cost, welcome to inquire! Figure 10 AW516X series module physical map 65W Interchangeable Power Adapter 65W Interchangeable Power Adapter,12V5A Interchangeable Power Adapter,Interchangeable Power Adapter With Ul,12V 5Aeu Us Plug Power Adapter Guangdong Mingxin Power Technologies Co.,Ltd. , https://www.mxpowersupply.com
