Kit 001

💻 Step 3 – Upload the Code

You’ve wired your system — now it’s time to make it smart.

We’ll upload a simple Arduino program that reads your soil moisture sensor and turns the water pump on when the soil gets too dry.

🧰 What You’ll Need

Arduino IDE installed
USB-C cable to connect your Arduino
The code below (or download from GitHub)

What This Code Does

Checks the sensor once per second
If the moisture level is too low (above 1000), it activates the pump
Otherwise, it keeps the pump off

const int moisturePin = A0;    // Moisture sensor connected to A0
const int relayPin = 7;        // Relay control pin
const int dryThreshold = 600; // Trigger threshold (adjust if needed)

void setup() {
  pinMode(relayPin, OUTPUT);
  digitalWrite(relayPin, HIGH); // Start with relay OFF
  Serial.begin(9600);          // For debugging
}

void loop() {
  int moisture = analogRead(moisturePin); // Read sensor value
  Serial.print("Moisture level: ");
  Serial.println(moisture);               // Print value to Serial Monitor

  if (moisture > dryThreshold) {
    Serial.print("Watering...");
    digitalWrite(relayPin, LOW); // Turn pump ON
    delay(5000);                  // Run pump for 5 seconds
    digitalWrite(relayPin, HIGH);  // Turn pump OFF
    Serial.print("Watering complete");
  }

  delay(2000); // Wait 2 seconds before next read
}

Select Your Board & Port

In Arduino IDE:
- Go to Tools → Board → Arduino Uno R4 WiFi
- Then Tools → Port and select your Arduino’s port (e.g., COM3 or /dev/tty.usbmodem...)

5. Click Upload

Hit the ✓ checkmark to verify
Click the → arrow to upload
Open Serial Monitor to see real-time moisture values

What’s a “Moisture Value”?

Dry soil = High value (usually 800–1023)
Wet soil = Low value (300–700)
You can tweak the if (moisture > 1000) value to make it more or less sensitive

Let's move on to the final step

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