Internal Error: Sub-system: VPR20KMAIN, File: /quartus/fitter/vpr20k/altera_arch_common/altera_arch_route_common.c, Line: 5472 - Internal Error: Sub-system: VPR20KMAIN, File: /quartus/fitter/vpr20k/altera_arch_common/altera_arch_route_common.c, Line: 5472 Description Due to a problem in the Quartus® II software version 11.1 SP2 and earlier, you may see this error when compiling designs containing a FIR Compiler II megafunction and targeting Arria® II devices. Resolution To work around this problem, in the MegaWizard™ Plug-in Manager, change the design implementation setting Small/Medium RAM Block Threshold from -1 to any positive integer. This problem is fixed beginning with the Quartus II software version 12.0 SP1. Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['FPGA Dev Tools Quartus II Software'] 12.0.1 11.0 ['Arria® II GX FPGA', 'Arria® II GZ FPGA'] ['novalue'] ['novalue'] ['novalue']