Verilog HDL Example Instantiation
dffe <instance_name> (.d(<input_wire>), .clk(<input_wire>), .clrn(<input_wire>), .prn(<input_wire>), .ena(<input_wire>), .q(<output_wire>));
Important:  To successfully
                                                  perform RTL simulation and formal verification,
                                                  use lowercase primitive name in
                                                  instantiation.