Internal Error: Sub-system: FMAIN, File: /quartus/fitter/fmain/fmain_location_constraint.cpp, Line: 2494 - Internal Error: Sub-system: FMAIN, File: /quartus/fitter/fmain/fmain_location_constraint.cpp, Line: 2494 Description This problem may be seen when you perform an ECO (Engineering Change Order) for designs with LogicLock regions in Quartus® II software versions 9.1 SP2 or earlier. To work around this problem, disable all LogicLock regions before performing ECO. If you then need to run a full compilation from HDL, re-enable the LogicLock regions. This problem is fixed in the Quartus II software version 10.1 and later. Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['novalue'] novalue novalue ['Programmable Logic Devices'] ['novalue'] ['novalue'] ['novalue']