With the rapid development of wireless communication technology, the demand for short-distance wireless communication technology is becoming more and more urgent. ZigBee is a new type of short-distance, low-speed wireless communication technology, which is a wireless remote technology and Bluetooth between the technical solution. Using multiple ZigBee modules to form a multi-level trunk self-organizing network system through wireless communication, and ZigBee can be used to perceive, collect and process ZigBee devices in the area, it can be widely used in medical care, environmental monitoring, military, commercial, electric power, transportation, finance, Agriculture, energy, smart home, automation and other fields.
For that communication--433 ZigBee is a networking protocol based on ad-set network and multi-point relay, which can realize mesh topology. This paper mainly introduces the networking principle of 433 ZigBee Module Wireless communication technology, and analyzes the ZigBee protocol model.
1. Equipment type of ZigBee network
In the ZigBee network, there are two different types of devices, called: coordination node, routing node.
1.1 Functions of the coordination node
The coordination node has and can only have one, is the core of the formation network.
Allows routing and termination nodes to join the network, routing data from the network.
1.2 Features of the routing node
You must first join a ZigBee network and allow other routes to join after joining the network.
After joining the network, you can route the data in the network.
2. How to send data
For the ZigBee module existing data transmission methods, mainly ZigBee unicast and broadcast two ways.
2.1 Unicast mode
Unicast mode is the data sent to a target device by a source device, in unicast mode, the data is issued by the source device, directly or after a few levels of transit, sent to the destination address. Unicast transmissions can be made between all devices that join the ZigBee network. The specific routing relationship is maintained and queried by the coordination node/routing node.
2.2 Broadcast Mode
The broadcast method is that the data is sent to all the devices in the whole network by a source device, and in the broadcast mode, the data is sent by one device directly or routed to all devices in the entire ZigBee network, and the destination address uses 16 FFFF. The broadcast mode is supported only by the coordinator in the device for that.
ZigBee Module Networking principle