module ClkGen_tb(); reg Clk_i; reg Rst_i; reg [3:0] clkDiv_i; always #(12.5/2) Clk_i = ~Clk_i; ClkGen ClkGen_inst ( .Clk_i(Clk_i), .Rst_i(Rst_i), .ClkDiv_i(clkDiv_i), .Clk_o() ); initial begin Clk_i = 0; Rst_i = 1; clkDiv_i = 3; #1000; Rst_i = 0; end endmodule