Constraints Window

The Constraints window is located in the bottom half of the main window directly above the Output window (see the figure below). Constraints are displayed in two groups, editable constraints and source constraints (read-only). The group displayed depends on the tab selected at the bottom of the window. As constraints are created, the UCF syntax appears in the editable group of the Constraints window. Constraints in the editable group are from the UCF and are editable by the Constraints Editor. Constraints in the source group are from the NCD and come from the netlist, the NCF, or the UCF (if the constraint is not supported by the Constraints Editor).

Figure 1.6 Constraints and Output Windows

By default, the Constraints window opens when you start the Constraints Editor, but it does not display information until you open a UCF/NGD file. For more on the Constraints window, see the “Constraints Window” section in the "Windows and Dialog Boxes" chapter.