You can display data from any valid data source by browsing for its location from the Data Source field. You can also browse for available data sources by clicking the Browse button and using the Data Source Browser.
Since the datalink returns only one value, when configuring a Historian data source, you do not need to set the data point interval (that is, your setting will not be used). The data point interval for all retrieval modes, except Raw By Number and Current Value, is equal to the time span, and the number of samples is always set to 1. Raw By Number returns the last point, and Current Value returns the current value and time of the tag.
For more information on browsing data sources, refer to the chapter The Data Source Browser.