/// <summary>
        /// Basic Circuit with 1 LED
        /// </summary>
        private Circuit createTestCircuit01()
        {
            PowerSource threeVolt = new PowerSource();
            TwoPinLED   led       = new TwoPinLED();
            Gpio        gpio      = new Gpio(17);

            threeVolt.On();

            // connect threevolt to anode
            threeVolt.AddRoute(threeVolt.PowerPin.PinId, led.Anode.PinId);

            // connect cathode to gpio
            led.AddRoute(led.Cathode.PinId, gpio.GpioPin.PinId);

            // no route needed at gpio (end node)

            // run through the circuit and try anurn each pin on
            return(new Circuit(threeVolt.NodeId, new List <Node> {
                threeVolt, led, gpio
            }, "TestCircuit"));
        }