Use the Prohibit Mode command to lock specified resources on the die to prevent PAR from placing logic at those locations. Select this command and then click or drag the mouse on the resources in the Device Architecture or Package Pins window that you want to prohibit. When the constraints file is generated, PACE creates a prohibit instance record for each prohibited resource. The block record instructs PAR not to place logic at those locations.
Note You cannot prohibit global buffers because you cannot specify this type of limitation in the constraints file without prohibiting the use of some IOBs.
Menu item: In the Tools menu, click Prohibit Mode.
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