The In Pin component is a circuit input pin, a source for a value of true or false. Anything it is connected to will receive a constant one value. The current state is indicated by the value 0 or 1 and an LED. Green indicates a value of one. The value can be changed from one to zero or zero to one (toggled) by clicking on the LED.

The names of inputs are significant to testing and are used as the inputs for reference components. Names must be unique in a given tab.