1. Introduction to the system
With the development and application of IoT technology, many emerging IoT platforms and protocols have emerged. LoRaWAN is a LoRa-based star network that uses the low power consumption and long-distance wireless communication features of LoRa modules. This network is suitable for various smart meter reading services. The LoRaWAN network consists of three main parts, the device side, the gateway and the server side.
lorawan network acquisition system
The following is the use of E78-DTU, E890-470LG11 wireless module LoRaWAN gateway to build a LoRaWAN automatic acquisition system. The LoRaWAN server adopts ChirpStack open source server. The schematic diagram of the whole system is as follows. The equipment side uses E78-DTU to connect with the collected equipment through RS485, E78-DTU communicates with the E890-470LG11 gateway through LoRa, the gateway forwards the data to the cloud server through the network, and the cloud server makes corresponding processing and forwards it to the client.
lorawan gateway server
After the configuration is complete, log in to the configuration website. The default account password is admin.
2. E890-470LG11 configuration process
Turn on the E890-470LG11 and use the laptop to connect to the WiFi of the gateway, named EBT-E890-XXXX. Enter 192.168.10.1 in the browser to enter the configuration page, and the password is root. The gateway ID matches the configured ID on the server, and the IP address is modified to the server's IP address. After the configuration is correct, the LINK light of the gateway will be always on to indicate that it is now connected to the server.
lorawan gateway settings
3. E78-DTU configuration process
E78-DTU uses the matching configuration host computer configuration. Select the corresponding serial port, open the serial port and click to enter the configuration, the server produces AppEUI and AppKEY, fill in 0 for APPEUI, then click Write Parameters to write the parameters into the device, and finally click to exit the configuration, if the configuration is correct, the device LINK light will be on.
E78-DTU digital radio gateway
Wireless modem
Configure the automatic polling parameters, and enter the corresponding command according to the polling data, the timeout time of the collected device, the collection interval and whether to add CRC check. The figure below is configured as a polling Modbus command, and the read coil, read discrete input register, read holding register, and read input register are added in sequence in the figure below. After adding two bytes of CRC-16 (Modbus) check.
Data radio modbus communication protocol
At the same time, the DTU is set to the polling mode as shown in the figure below, and the interval between two large polling events can be set according to actual needs.
DTU digital radio gateway polling mode
4. Client configuration
Here, use the MQTTX software to subscribe to the upstream data topic of the Chirpstack server, first connect to the Mqtt server, and enter the correct server address and port.
The automatic acquisition system built with Chirpstack, E890-470LG11 and E78-DTU can quickly build an IoT network, simplifying the process of building end-to-cloud, while using LoRa radio frequency technology to improve the communication distance, improve the communication distance of equipment, and automatically collect data It can simplify the collection process and save labor costs. Networks built with Chirpstack servers can reduce device management.
Post je objavljen 22.08.2022. u 07:47 sati.