Example Code for Arduino-Liquid Level Detection with LED Indication

Hardware Preparation

• DFRduino UNO R3
• Capacitive Tube Liquid Level Sensor

Software Preparation

Click to download Arduino IDE

Wiring Diagram

Sample Code

int ledPin = 13; // LED connected to digital pin 13
int inPin = 7;   // pushbutton connected to digital pin 7
int val = 0;     // variable to store the read value

void setup()
{
  pinMode(ledPin, OUTPUT);      // sets the digital pin 13 as output
  pinMode(inPin, INPUT);      // sets the digital pin 7 as input
}

void loop()
{
  val = digitalRead(inPin);   // read the input pin
  digitalWrite(ledPin, val);    // sets the LED to the button's value
}

Result

If the sensor detects liquid, the onboard LED of UNO will turn off. If no liquid is detected, the onboard LED of UNO will turn on.