Sending values to MQTT

In this example we'll configure Clarity Gateway to send the value of an Iron Pi analog input to an MQTT connection.

Bulk mapping via the channels table

In the page for your MQTT connection, scroll down to the Channels To MQTT section. Click the Show All Tags switch if it is not already on:

All system tags in Clarity Gateway will then appear in the table. In this example we'll be mapping Local I/O channel 1, which is configured as an analog input and mapped to the system tag channel1:

First check the Enabled checkbox to enable this mapping:

Then enter the MQTT Tag to send values to. In this example we'll use localio/channel1:

Finally, click Save:

Once the mapping is applied, the arrow should change color from gray to blue to indicate that the mapping is active:

Advanced mapping

For more options when mapping a channel, click the + icon in the Channels To MQTT section:

This will take you to a separate Create Channel page. In that page, first enter the Clarity Gateway System Tag you would like to send to MQTT. In this example, we'll be using channel1, which is configured as a Local I/O analog input:

Optionally, you can enter a Slope and Offset to transform the values that get sent to MQTT. In this example we will enter 2 and 3:

Finally, enter the MQTT Tag to send to and Data Type to use. In this example, we'll send values to localio/channel1 as Floats:

Finally, click Save to create the channel:

Once the channel has been created, you will return to the connection page. The new channel should appear in the Channels To MQTT table. Notice how the system value is 9.68, and the value sent to MQTT is 2 * 9.68 + 3 = 22.2: