Quartus® Prime Pro Edition User Guide: Design Optimization

ID 683641
Date 7/08/2024
Public
Document Table of Contents

4.2.4.4. Guideline: Remove Fitter Constraints

A design with conflicting constraints or constraints that are difficult to meet may not fit in the targeted device. For example, a design might fail to fit if the location or Logic Lock assignments are too strict and not enough routing resources are available on the device.

To resolve routing congestion caused by restrictive location constraints or Logic Lock region assignments, use the Routing Congestion task in the Chip Planner to locate routing problems in the floorplan, then remove any internal location or Logic Lock region assignments in that area. If your design still does not fit, the design is over-constrained. To correct the problem, remove all location and Logic Lock assignments and run successive compilations, incrementally constraining the design before each compilation. You can delete specific location assignments in the Assignment Editor or the Chip Planner. To remove Logic Lock assignments in the Chip Planner, in the Logic Lock Regions Window, or on the Assignments menu, click Remove Assignments. Turn on the assignment categories you want to remove from the design in the Available assignment categories list.