Error: Fractional PLL parameter 'pll_cp_current' is set to an illegal value - Error: Fractional PLL parameter 'pll_cp_current' is set to an illegal value Description Due to a problem in Quartus® II Software version 13.0 and earlier, you may see this error message when you set the partition containing your PLL to post-fit. Resolution To work around the problem, find the PLL Quartus II IP File ( .qip ) file and expand the PLL instance names fully. For example: Change the following statements in .qip from: set_instance_assignment -name PLL_COMPENSATION_MODE NORMAL -to "*cpui_serial_pll_0002*|altera_pll:altera_pll_i*|*" set_instance_assignment -name PLL_AUTO_RESET OFF -to "*cpui_serial_pll_0002*|altera_pll:altera_pll_i*|*" set_instance_assignment -name PLL_BANDWIDTH_PRESET HIGH -to "*cpui_serial_pll_0002*|altera_pll:altera_pll_i*|*" to: set_instance_assignment -name PLL_COMPENSATION_MODE NORMAL -to "cpui_top:cpui_top|cpui_serial:sbus|cpui_serial_pll:rx_pll|cpui_serial_pll_0002:cpui_serial_pll_inst|altera_pll:altera_pll_i" set_instance_assignment -name PLL_AUTO_RESET OFF -to "cpui_top:cpui_top|cpui_serial:sbus|cpui_serial_pll:rx_pll|cpui_serial_pll_0002:cpui_serial_pll_inst|altera_pll:altera_pll_i" set_instance_assignment -name PLL_BANDWIDTH_PRESET HIGH -to "cpui_top:cpui_top|cpui_serial:sbus|cpui_serial_pll:rx_pll|cpui_serial_pll_0002:cpui_serial_pll_inst|altera_pll:altera_pll_i" This problem is fixed beginning with Quartus II software version 13.1. Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['FPGA Dev Tools Quartus II Software'] 13.1 novalue ['Programmable Logic Devices'] ['novalue'] ['novalue'] ['novalue']