In the HMI/Dashboard, application gets data from the device using a Modbus request, that process is performed periodically in the specified interval.
This kind of process makes the bandwidth bigger, because the latest data and unchanging data are still sent to the dashboard application.
But.. by using MQTT protocol, only the latest ones are sent to the dashboard application, so the bandwidth usage becomes less.
For that reason, I tried to develop a MQTT Broker for Modbus protocol.
To use this MQTT Broker, it is very easy. First, we have to record the user and password that is allowed to get data from the device.
Next, we will create the names of the topics that will be subscribed by the user. And lastly, we connect this topic that has been made with Modbus address, so if there is a change of data in the device, then through the topic, the Dashboard will get the last data.
houston/dev01/pressure is set to Modbus Slave ID 1 at Holding Register Address 7001.
This MQTT Broker for Modbus tcp/ip is FREEWARE. So you can download here:
There are 2 files RAR in this folder:
1. MQTT broker for Modbus protocol
2. DDE Server for MQTT protocol, used for HMI / Dashboard apps like Wonderware inTouch.
Or, you can download any native MQTT Client for mobile dashboard application in apps store.
Thanks for the support.