System generation fails if Cyclone IV GX device information is not installed with the Quartus II software version 10.1 - System generation fails if Cyclone IV GX device information is not installed with the Quartus II software version 10.1 Description SOPC Builder and Qsys require Cyclone IV GX device information during system generation. If Cyclone IV GX device information is not installed with the Quartus II software version 10.1, system generation fails with the following error: Family name "Cyclone IV GX" is illegal . Resolution Install Cyclone IV GX device family to the Quartus II software. Custom Fields values: ['novalue'] Troubleshooting novalue True ['novalue'] ['FPGA Dev Tools Quartus II Software'] novalue 10.1 ['Cyclone® IV FPGAs'] ['novalue'] ['novalue'] ['novalue']