`timescale 1ns/1ps `default_nettype none module example1_tb (); reg clk = 0; initial forever #5 clk = !clk; wire strobe; example1 count (.clk(clk), .strobe(strobe)); initial begin `ifdef VCD_DUMP $dumpfile("counter_tb.vcd"); $dumpvars(0,example1_tb); `endif end initial begin `ifdef END_TIME #`END_TIME $finish(); `else #1000 $finish(); `endif end initial begin #500 $finish(); end always @(posedge clk) begin if (strobe) $display("Strobe"); end endmodule