Error (15629): Atom "comb~6" is dependent on unconnected input ports - Error (15629): Atom "comb~6" is dependent on unconnected input ports Description You may see the error when instantiating the Altera® PLL Reconfiguration IP and enabling physical synthesis in the Quartus® II software. Resolution Modify the altera_pll_reconfig_core.v file as shown below: Find the generic_lcell_comb module definition Add (* altera_attribute = "-name ADV_NETLIST_OPT_ALLOWED \"NEVER ALLOW\"" *) before the module keyword. This problem is fixed in Quartus® Software version 13.1. Related Articles Error (15629): Atom comb~0 is dependent on unconnected input ports Error ID 15629: Atom lcell_inst is dependent on unconnected input ports Custom Fields values: ['novalue'] Troubleshooting 1408035447 False ['PLL Reconfig IP'] ['FPGA Dev Tools Quartus II Software'] 13.1 13.1 ['Arria® V GT FPGA', 'Arria® V GX FPGA', 'Arria® V GZ FPGA', 'Arria® V ST FPGA', 'Cyclone® V E FPGA', 'Cyclone® V GT FPGA', 'Cyclone® V GX FPGA', 'Cyclone® V SE FPGA', 'Cyclone® V ST FPGA', 'Cyclone® V SX FPGA', 'Stratix® V E FPGA', 'Stratix® V GS FPGA', 'Stratix® V GT FPGA', 'Stratix® V GX FPGA'] ['novalue'] ['novalue'] ['novalue']