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Wireless Data Acquisition System - LoRa Gateway BL280
Note:
①
Above is only for node WT101. If it’s not WT101, the read value is 0. When node ID is n,
the corresponding mapping address is (n-1)*4; if it’s not WT101 ID, the read value is 0
12 Appendix C MQTT Application
(1) MQTT Introduction
MQTT is client-server based message publishing/subscription transmission protocol. It is a
lightweight, simple, open and easy to implement protocol that can be used in many areas, including
constrained environment like M2M and IoT. It has been widely used in satellite link communication
sensors, network medical devices, smart home and other small size equipment. MQTT runs through
TCP/IP or other network protocols to provide orderly, lossless and bi-directional connection.
(2) MQTT Principle
There are 3 identities in MQTT protocol: Publisher, Broker, Subscriber. Both message publisher and
subscriber are clients. Message broker is server. Message publisher can be subscriber at the same
time. Below is the example of connecting Gateway BL280 to King Pigeon Cloud 2.0 via MQTT:
Device publishes I/O data:
Broker
King Pigeon Cloud 2.0
User controls device:
Broker
King Pigeon Cloud 2.0
(3) Client Configuration
Below is the example of King Pigeon Cloud 2.0 configuration. For Alibaba Cloud and HUAWEICloud,
input the corresponding parameters.
Publisher
BL280
Subscriber
User
Account
Publish message
Subscribe message
Push message
Publisher
User Account
Subscriber
BL280
Publish message
Subscribe message
Push message