This is an example of MQTT Client made of Arduino and Ethernet compatible board. It is used as weather station by having MQTT Broker and MQTT Client at the garden and office.
What is MQTT?
MQTT protocol is based on exchanging messages by using Publish and Subscribe. Based on ‘Topic’, we can receive the data if other client would publish the subscribed Topic. Many clients can subscribe one Topic.
The author used Arduino+Ethernet PoE(Power over Ethernet) and would publish the weather information sensed by temperature-humidity sensor, atmospheric pressure, and illumination sensor periodically.
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