In MQTT the process of

  • sending messages is called publishing,
  • and to receive messages, an MQTT client must subscribe to an MQTT topic.




Visualization of publishing and subscribing of MQTT topics

Here you can see on our industrial HMI:

Publishing (Left) and subscribing (Right) of MQTT topics.

For each line, we publish and subrscribe to the same MQTT topic.

This is managed by our Modbus <> MQTT gateway connected to the USB port of our industrial ACE PLC !!