Introduction
It is sometimes a requirement of an HMI application to write a fixed or variable value to a data register in a PLC at the touch of a button. This document explains how this can be done with any current range GOT HMI.
Design Considerations
With an HMI project open in GT Designer software and a base screen open for editing, a “data set switch” object can be found from the Switch section of the Object menu. Once the data set switch is placed on screen and double clicked for editing, the following selections can be made as shown below:
- enter a PLC address into the Device selection (this is where the value will be written)
- tick either the Fixed or Indirect selection for the Set Value option (this is where the value will come from)
- entering a Fixed value into the Set Value option will write this value to the PLC address specified in the Device above
- entering another PLC address in the Indirect setting of the Set Value option will write the value from the indirect address to the address specified in the Device above
Example:
Setup the “data set switch” to copy the value in D100 to D0 when a data set switch is pressed.
This is a very simple example but when the other features of a data set switch are taken into account, it is possible to extend the functionality of this simple feature to do more complicated things. See extended functions such as “Extended”, “Action” and “Trigger”.
Further Information
For further information, please refer to the GX Designer help files and GOT manuals or contact our support desk (support@adroit.co.za).
You can download this Tip in PDF format here.
