First knowledge of ZigBee technology 1 Zigbee protocol

First knowledge of ZigBee technology 1 Zigbee protocol

1. ZigBee is a short-distance, low-rate wireless data transmission protocol (IEEE 802.15.4 protocol ).

Wireless network operating frequency: 868 MHz, 915 MHz, 2.4 GHz

Maximum data transmission rate: 250 kbps

 

2. Zigbee protocol:

2.1 Adopt a layered approach and different layers are responsible for different functions. Similar to the layer-7 ISO model in Ethernet (physical layer, Data Link, network layer, transmission layer, Session Layer, presentation layer, and application layer ).

ZigBee wireless networks can be divided into several layers:

Physical Layer (PHY)

Media access layer (MAC)

Network Layer (nwk)

Application Layer (APL): Includes Application Support Sub-layer (APS), application framework, and Application Object (zdo)

Among them, the physical layer (PHY) and the media access layer (MAC) are the data transmission specifications defined in 802.15.4.

Layered thinking: the adjacent two layers can exchange data (for example, the network layer can only provide function call services for the upper layer of the application layer. After the service is complete, the results are returned to the application layer. However, the network layer can only request services from the next layer of media. After the services are completed, the results are returned to the network layer. In this way, each layer is responsible for its own functional modules)

2.2 there are three types of ZigBee wireless networks:

Coordinator: responsible for establishing and maintaining networks. (Equivalent to an Ethernet server)

Router: Responsible for routing network data. (Equivalent to a vro in Ethernet)

End device: Collects network data. (Equivalent to computers in Ethernet)

2.3 protocol features: high reliability, low cost, low power consumption, and low speed.

2.4 The zigbee2007 Protocol specifies two Protocols: Zigbee and ZigBee pro.

2.5 wireless network topology:

Star Network Topology

Network Topology (mainly used here)

Reference

Design and Implementation of ZigBee Wireless Sensor Networks edited by Wang Xiaoqiang and others

ZigBee video tutorial Application Development Guide-Based on Ti TI-CC2530 RF microcontroller chip Feng Shuo company Wang Feng recording