Open RSLinx, then on top menu, click "DDE/OPC" and configure a DDE Topic. Add a new topic, then under "Data Collection" click "Use Symbols", then select a previously saved spreadsheet (saved as a CSV file) for the symbol names.
In RSLinx, a topic represents a specific path to a processor. If you right-click on a station in RSWho and select Configure DDE Topic, or if you select DDE > Topic Configuration, the DDE/OPC Topic Configuration dialog box displays.
A DDE project is a storage container for one or more DDE topics. If you attempt to create a DDE topic without having created a DDE project, a default DDE project is created for you.
If you selected Configure DDE Topic by right-clicking on a station in RSWho, the Topic Name field is pre-filled for you. RSLinx starts with the name of the program running in the processor, and if this DDE topic exists, it adds a number to the end until it finds one that does not exist. If there are any spaces, it converts them to _'s. You can change the topic name RSLinx selected for you.