Arduino program to interface soil moisture sensor

Interfacing a soil moisture sensor with an Arduino involves reading the analog values from the sensor and displaying the readings. Here is a simple Arduino program to do that:

Hardware Required:

• Arduino board (e.g., Uno)
• Soil moisture sensor
• Breadboard and jumper wires

Connections:

• Connect the VCC pin of the soil moisture sensor to the 5V pin of the Arduino.
• Connect the GND pin of the sensor to the GND pin of the Arduino.
• Connect the analog output pin (usually labeled A0 or AO) of the sensor to an analog input pin on the Arduino (e.g., A0).

// C++ code
//
int moisture = 0;

void setup()
{
  pinMode(A0, OUTPUT);
  pinMode(A1, INPUT);
  Serial.begin(9600);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(12, OUTPUT);
}

void loop()
{
  // Apply power to the soil moisture sensor
  digitalWrite(A0, HIGH);
  delay(10); // Wait for 10 millisecond(s)
  moisture = analogRead(A1);
  // Turn off the sensor to reduce metal corrosion
  // over time
  digitalWrite(A0, LOW);
  Serial.println(moisture);
  digitalWrite(8, LOW);
  digitalWrite(9, LOW);
  digitalWrite(10, LOW);
  digitalWrite(11, LOW);
  digitalWrite(12, LOW);
  if (moisture < 200) 
  {
  	digitalWrite(12, HIGH);
  } 
  else if (moisture < 400) 
  {
      digitalWrite(11, HIGH);
  } 
  else if (moisture < 600) 
  {
        digitalWrite(10, HIGH);
  } 
  else if (moisture < 800) 
  {
       digitalWrite(9, HIGH);
  }
  else 
  {
      digitalWrite(8, HIGH);
  }
  
  delay(100); // Wait for 100 millisecond(s)
}