Page History

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• Installing the Java Runtime Environment
• Installing Ignition
• Installing the following MQTT Modules
  • MQTT Distributor
    • v2.1.X if using Ignition 7.7.x or 7.8.x
    • v3.1.0 or greater if using Ignition 7.9.X
  • MQTT Engine
    • v2.1.X if using Ignition 7.7.x or 7.8.x
    • v3.1.0 or greater if using Ignition 7.9.X

Overview:

MQTT Engine provides a mechanism for publishing MQTT Messages from an Ignition script.  This can be useful for general messaging outside of Sparkplug.  For example, one may want to interface to another system that uses MQTT.  This method allows arbitrary MQTT messages to be published based on events that exist in Ignition. 

MQTT Message Publishing via Ignition Script:

Start by opening an Ignition Designer window and double clicking 'ProjectScripting-> Gateway Event Scripts' from the Project Browser as shown below:Image Removed

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Now select 'Tag Change' click the 'new Tag' icon at the bottom of the window shown below.

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Set the name of the script and then select a tag path.  In this case we're using an MQTT Engine tag from an emulated device.

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Now select the 'Script' tab near the top.  In it, type the following line:

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When complete, the script should look something like this.  Now click OK.

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Finally, save and publish the project.  At this point every time this tags value, quality, or timestamp changes it will result in a MQTT message being published on topic 'a/b/c' with a payload of 'hello world'.