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Tip
Discuss PLDs with others at our discussion group.

In the main tutorial, I've used the constraint editor to set the pin numbers. If you are working in the schematic editor, there is another way you may (or may not prefer). In general, you can set any constraint you want by bringing up the object properties for a schematic element.

The LOC constraint lets you assign a pin number to a pad. Simply right click on the pad and pick Object Properties. Use the New button to add a LOC attribute and make its value the pin number you want (precede pin numbers with P so pin 80 is P80):

That's all there is to it. You can find a complete list of constraints in the Xilinx documentation.