Potentiometer Reading

Read a potentiometer and display its value on the serial monitor.

Beginner
Input & Controls
2 parts

Opens in your browser with the parts, wiring and code already in place. Press Run to watch it work, then change anything you like.

How it works

A potentiometer is a knob that divides a voltage. Its two outer pins connect to 5V and ground, and the middle pin, the wiper, outputs a voltage anywhere between 0 and 5 volts depending on where the knob is turned. The wiper is wired to analog pin A0.

analogRead(A0) turns that voltage into a whole number from 0 (0 volts) to 1023 (5 volts). loop() reads it twice a second and prints “Pot value: ” followed by the number to the Serial tab. Select the potentiometer in the editor and drag its value to watch the number change.

Parts

Arduino Uno
Potentiometer

Wiring

Arduino Uno 5V → Potentiometer VCC
Potentiometer Wiper → Arduino Uno A0
Arduino Uno GND → Potentiometer GND

Arduino code

// Potentiometer Reading
void setup() {
  Serial.begin(9600);
}

void loop() {
  int val = analogRead(A0);
  Serial.print("Pot value: ");
  Serial.println(val);
  delay(500);
}

Try changing it

Print volts instead of the raw number: replace Serial.println(val) with Serial.println(val * 5.0 / 1023.0).
Read more often by changing delay(500) to delay(50).

Open this circuit and run it

Next challenge

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