Distributed Control & Automation Framework (DCAF)

DCAF Tag Select Module Documentation

Overview

Allows users to use one tag to select between two other tags.

Description

The Tag Select Module is the DCAF equivalent of the LabVIEW Select Node.

It lets users choose between two data tags with a single selector tag.

Configuration of the Tag Select Module

To configure a new tag selector, hit the '+' button and choose a name for it. Use the '-' to remove it. Once you have created a selector, you need to choose the data type of the tags you are passing through. Then you need to assign tags to the inputs, select, and output. To edit a cell, select it. To edit the Data Type cell, double click it.

Output Tag Tag that comes out of the module.

Input Tag (F) Tag that is output if Select Tag is false.

Input Tag (T) Tag that is output if Select Tag is true.

Note: The Output Tag and both Input Tags must have the same data type that is selected in the 'Data Type' column.

Using the Tag Select Module

In the gif below, the UI Module of DCAF is connected to the Tag Select Module to show it's operation. As seen in the gif, the output can come from either of the input buttons, depending on the value of the select.

Source Code Design

The Tag Select Module works be iterating through each of the channels configured in the table, and choosing the parameter to pass to the results based on the value of the tag being read. It uses the indices to read and write the tags for maximum performance.