Answers Database 2.1i: Floorplanner (4kxl): ERROR:x4kma:387 - Unable to obey design constraints which require... Record #6358 Product Family: Software Product Line: Merged Core Product Part: Floorplanner Product Version: 2.1i Problem Title: 2.1i: Floorplanner (4kxl): ERROR:x4kma:387 - Unable to obey design constraints which require... Problem Description: Urgency: Standard General Description: After placing several components or 'Replace All with Placement' in Floorplanner, then running map, the following errors occur for 4000xl, while packing: ERROR:x4kma:387 - Unable to obey design constraints which     require the combination of the following symbols into a single     CLB:       ADD32 symbol "I$2"       ADD32 symbol "I$2" OR    ERROR:x4kma:387 - Unable to obey design constraints which require the combination of the following symbols into a single CLB:      FDCE Symbol .....      FDCE Symbol .....      FDCE symbol ..... Solution 1: The mapper can create replicated logic for a design for several reason, but that replicated logic being placed in floorplanner with carry logic is not supported in map. In this case, the symbols shared teh same LOC paramter. This will be fixed in a future release. Solution 2: the design has the same BLKNM on three FFs and that the mapper is allowing this erroneous design to be processed with only a warning in the first iteration - When the floorplanner constraints are used to run map, the floorplanner constraints are converted to LOCs and since the LOC constraints must be obeyed, the design errors out. The solution is to modify the design so that no more than two FFs have the same BLKNM. End of Record #6358 - Last Modified: 07/13/99 08:54

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