// Stimulus module for (switch-level) CMOS inverter module stimulus; reg in; // declare register inputs wire out; // declare output inv_sw I0 (out, in); // call inverter initial begin #2 $display ("in - out"); forever #5 $display ("%b - %b", out, in); end initial begin #5 in=1'b1; #5 in=1'b0; #5 in=1'b1; #5 in=1'b0; #5 in=1'b0; #5 in=1'b1; #5 in=1'b0; #5 in=1'b1; #5 in=1'b0; #5 $finish; end endmodule