Example: Using the MQTT Client SL Library

Command to install the Mosquitto broker:

sudo apt-get install mosquitto mosquitto-clients

Command to start and stop the service:

sudo service mosquitto start
sudo service mosquitto stop

Commands for testing:

mosquitto_sub -d -V mqttv311 -t hello/world
mosquitto_pub -d -V mqttv311 -t hello/world -m "Hello!"

The MQTT Client SL Example.project sample project shows how to use the function blocks and can be used for testing purposes. All inputs of the function blocks can be configured from the visualization. The example contains two subscribers and two publishers.

Figure 14. Sample application: MQTT Client SL Example.project