public Testbench() { _clkgen = new Clock(ClockPeriod) { Clk = _clk }; _gcd = new GCD() { Clk = _clk, A = _a, B = _b, R = _r1 }; _adder = new Adder() { Clk = _clk, A = _a, B = _b, C = _c, D = _d, R = _r2 }; }