Circuit Documentation

Summary

This circuit is designed to monitor soil moisture levels and control a water pump based on the moisture content. It features an Arduino UNO microcontroller interfaced with an HC-05 Bluetooth module for wireless communication, a rain/snow sensor for detecting moisture levels, an LED board as an indicator, a 5V relay to control the water pump, and a 5V mini water pump for irrigation. The system operates in both automatic and manual modes, allowing for remote control via Bluetooth commands.

Component List

Arduino UNO

• Microcontroller board based on the ATmega328P
• Used for controlling the entire circuit, reading sensor data, and communicating with the Bluetooth module

HC-05 Bluetooth Module

• Wireless communication module
• Enables remote control of the circuit via Bluetooth

LED Board

• Visual indicator
• Used to display the status of the system or alerts

Rain/Snow Sensor - Board

• Moisture detection sensor
• Measures the moisture level in the soil

5V Relay

• Electromechanical switch
• Controls the power supply to the water pump

5V Mini Water Pump

• Actuator for pumping water
• Used to irrigate the soil when moisture levels are low

5V Battery

• Power source
• Supplies power to the water pump

Wiring Details

Arduino UNO

• 5V connected to VCC of relay, LED board, HC-05 Bluetooth module, and rain/snow sensor
• GND connected to GND of relay, LED board, HC-05 Bluetooth module, and rain/snow sensor
• A0 connected to A0 (Analog) of rain/snow sensor
• D8 connected to In of relay
• D1 (TX) connected to RXD of HC-05 Bluetooth module
• D0 (RX) connected to TXD of HC-05 Bluetooth module

HC-05 Bluetooth Module

• VCC connected to 5V of Arduino UNO
• GND connected to GND of Arduino UNO
• TXD connected to D0 (RX) of Arduino UNO
• RXD connected to D1 (TX) of Arduino UNO

LED Board

• VCC connected to 5V of Arduino UNO
• GND connected to GND of Arduino UNO

Rain/Snow Sensor - Board

• A0 (Analog) connected to A0 of Arduino UNO
• GND connected to GND of Arduino UNO
• VCC (5V) connected to 5V of Arduino UNO

5V Relay

• VCC connected to 5V of Arduino UNO
• GND connected to GND of Arduino UNO
• In connected to D8 of Arduino UNO
• Normally Open connected to - of 5V Battery
• Common terminal connected to negative pin of 5V mini water pump

5V Mini Water Pump

• positive pin connected to + of 5V Battery
• negative pin connected to Common terminal of 5V relay

5V Battery

• + connected to positive pin of 5V mini water pump
• - connected to Normally Open of 5V relay

Documented Code

#define moistureSensorPin A0       // Soil moisture sensor pin
#define ledPin 7                   // LED pin
#define relayPin 8                 // Relay pin for motor control
#define thresholdPercent 20        // Moisture level threshold percentage

char value;                        // Variable for Bluetooth command
int moistureValue = 0;             // Variable for soil moisture reading
int moisturePercent = 0;           // Variable for moisture level in percentage

void setup() {
  Serial.begin(9600);              // Initialize serial communication for Bluetooth
  pinMode(ledPin, OUTPUT);         // Set LED pin as output
  pinMode(relayPin, OUTPUT);       // Set Relay pin as output for motor control
  digitalWrite(ledPin, LOW);       // Ensure LED is off initially
  digitalWrite(relayPin, LOW);     // Ensure motor is off initially
}

void loop() {
  BluetoothControl();              // Call Bluetooth control function
}

void BluetoothControl() {
  if (Serial.available() > 0) {    // Check if data is available from Bluetooth
    value = Serial.read();         // Read the incoming data
  }

  if (value == 'M') {
    ManualOperation();             // Execute Manual Mode
  } else if (value == 'A') {
    AutomaticOperation();          // Execute Automatic Mode
  } else {
    AutomaticOperation();          // Default to Automatic Mode if Bluetooth is disconnected
  }
}

void AutomaticOperation() {
  moistureValue = analogRead(moistureSensorPin);            // Read soil moisture value
  moisturePercent = map(moistureValue, 1023, 0, 0, 100);    // Convert to percentage
  
  Serial.print("Automatic Mode - Moisture Level: ");
  Serial.print(moisturePercent);
  Serial.println("%");                                      // Send moisture level as percentage
  
  if (moisturePercent < thresholdPercent) {
    digitalWrite(relayPin, HIGH);                           // Turn motor ON if soil is below 20%
    Serial.println("Soil moisture is low. Motor ON.");
  } else {
    digitalWrite(relayPin, LOW);                            // Turn motor OFF if soil is above 20%
    Serial.println("Soil moisture sufficient. Motor OFF.");
  }
  delay(1000);                                              // 1-second delay for consistent readings
}

void ManualOperation() {
  moistureValue = analogRead(moistureSensorPin);            // Read soil moisture value
  moisturePercent = map(moistureValue, 1023, 0, 0, 100);    // Convert to percentage
  
  Serial.print("Manual Mode - Moisture Level: ");
  Serial.print(moisturePercent);
  Serial.println("%");                                      // Send moisture level as percentage

  Serial.println("Send '1' to turn LED ON, '0' to turn LED OFF"); // Prompt for LED control
  Serial.println("Send '2' to turn Motor ON, '3' to turn Motor OFF"); // Prompt for Motor control
  
  if (Serial.available()) {
    char manualCommand = Serial.read();                    // Read command for LED and Motor control
    
    if (manualCommand == '1') {
      digitalWrite(ledPin, HIGH);                          // Turn LED on
      Serial.println("LED ON");
    } else if (manualCommand == '0') {
      digitalWrite(ledPin, LOW);                           // Turn LED off
      Serial.println("LED OFF");
    } else if (manualCommand == '2') {
      digitalWrite(relayPin, HIGH);                        // Turn motor on via relay
      Serial.println("Motor ON");
      Serial.print("Moisture Level: ");
      Serial.print(moisturePercent);
      Serial.println("%");                                 // Send moisture level as percentage
    } else if (manualCommand == '3') {
      digitalWrite(relayPin, LOW);                         // Turn motor off via relay
      Serial.println("Motor OFF");
      Serial.print("Moisture Level: ");
      Serial.print(moisturePercent);
      Serial.println("%");                                 // Send moisture level as percentage
    }
  }
}

This code is designed to run on the Arduino UNO microcontroller. It reads the soil moisture level from the rain/snow sensor and controls the water pump through the relay based on the moisture level. It also allows for manual control of the LED and pump via Bluetooth commands.