Page 106 - Programming the Photon Getting Started With the Internet of Things

Figure 5.6 Breadboard layout diagram for reading a potentiometer.

As you turn the potentiometer you vary the voltage that feeds directly into the analog
pin on the Photon between 0 and 3V3. If you have a digital multimeter handy, you can
confirm the value when you turn the knob—simply change your multimeter value to

voltage, hook up the red probe (positive) to the middle pin on the POT, and hook up the
black probe (negative) to whichever side you have the POT connected to ground.

Here is the basic example sketch for reading analog input and using the value to create
some output:

const int POT = A0;
const int led = A1;

int val = 0;

void setup() {
pinMode(led, OUTPUT);
pinMode(POT, INPUT);

}