Using buttons – button press function

Buttons come in all shapes and sizes. Some are quiet. Some are noisy. Some are expensive. Some cost pennies. We'll not only use the cheap and peppy, penny variety, but also show an example with a more interesting, whizzy personality and make it do something more than just turn the switch on and off.

Pull-up, pull-down, and floating

Frequently when wiring up circuits, you will hear references to pull-up, pull-down, and floating configurations. When your design is a pull-up circuit, this means that the resistor holds the positive or supply voltage (VCC) until you push the button pulling it up to ground. This is the most common scenario, and one you encounter when you design a circuit with a button press to activate something.

In the pull-down version of a circuit, the resistor in the circuit remains at ground unless you push (or pull down) the button, causing the circuit to switch from ground to positive or supply voltage (VCC).

Floating means...