Touch

Detecting touch without having a button has become very common in the past few years. The technology is found on refrigerators, microwave ovens, and TVs. It is also similar to how touch screens work on phones and tablets.

Touch sensing relies on measuring a very small capacitance found in the environment. When a pin is touched by a finger, the capacitance is changed and a touch is detected. This is why this is sometimes called capacitive touch sensing.

For capacitive sensing to work, a 100pF capacitor needs to be connected between the desired pin and ground. Fear not, those are already found on pins 0, 1, and 2 on all boards.

@Loop
    t = TouchRead(0)
    Println(t)
    Wait(500)
Goto Loop

BrainStorm

Where do you see capacitive touch used daily? By you? Have you ever touched a phone’s or tablet’s screen?