How to ignore simulation only ports when mapping to FPGA pins? - How to ignore simulation only ports when mapping to FPGA pins? A design has a number of simulation ports that should not be tied to FPGA pins. A VHDL example is shown in the source below, where the sim_only_* ports are for simulation only, thus should not be mapped to FPGA pins. entity mdl is port( -- FPGA pins clk_i : in std_logic; rst_i : in std_logic; a_i : in std_logic; z_o : out std_logic; -- Simulation pins only sim_only_in : in std_logic := '0'; sim_only_out : out std_logic); end entity; The sim_only_* pins can be safely left unused by Quartus, since the inputs have default value. When running Quartus, the mapper tries to map the sim_only_* ports to unused FPGA pins, which is not desired. How can I specify that Quartus should just ignore the sim_only_* ports on the VHDL design? Replies: Re: How to ignore simulation only ports when mapping to FPGA pins? Hi @MoZdk I’m glad that your question has been addressed, I now transition this thread to community support. If you have a new question, feel free to open a new thread to get the support from Intel experts. Otherwise, the community users will continue to help you on this thread. Thank you. Best Regards, Richard Tan p/s: If any answer from the community or Intel support are helpful, please feel free to give Kudos. Replies: Re: How to ignore simulation only ports when mapping to FPGA pins? Use Virtual Pin assignments in the Assignment Editor. That way the logic for the pins will still be implemented but they won't get connected to physical I/O.