IoT-based Smart Agriculture System Documentation

Summary

This document provides a detailed overview of an IoT-based Smart Agriculture System. The system automates farm management by monitoring environmental conditions such as temperature and soil moisture and controlling irrigation using a water pump. It also sends alerts and updates via a GSM module, enhancing farm efficiency and sustainability with automated and remote monitoring.

Component List

1. Temperature Sensor (LM35)

   • Description: Measures temperature.
   • Pins: +Vs, Vout, GND

2. HC-SR501 PIR Motion Sensor

   • Description: Detects motion.
   • Pins: Output, Ground, Power Supply

3. Capacitive Soil Moisture Sensor V1.2

   • Description: Measures soil moisture.
   • Pins: GND, VCC, AOUT

4. LED: Two Pin (red)

   • Description: Indicates status.
   • Pins: Cathode, Anode

5. Resistor (220 Ohms)

   • Description: Limits current.
   • Pins: Pin1, Pin2

6. Resistor (10k Ohms)

   • Description: Limits current.
   • Pins: Pin1, Pin2

7. Arduino Mega 2560

   • Description: Main microcontroller.
   • Pins: IOREF, RESET, 3V3, 5V, GND, VIN, A0-A15, D0-D53, AREF, SDA, SCL

8. 5V Mini Water Pump

   • Description: Controls water flow.
   • Pins: Positive Pin, Negative Pin

9. SIM900A

   • Description: GSM module for communication.
   • Pins: GND, DB9-3 (RXD), DB9-2 (TXD), 5V, 3VR, 5VR, 3VT, 5VT, VCC, Ring, RESTART, RESET, STATUS

10. 12V Single Channel Relay

    • Description: Controls high voltage devices.
    • Pins: NC, COM, NO, IN, GND, VCC

11. Buzzer

    • Description: Provides audible alerts.
    • Pins: Positive, Negative

12. Lipo Battery 2200mAH 30c

    • Description: Power source.
    • Pins: VCC, GND

13. ESP-8266 Controller

    • Description: Wi-Fi module for communication.
    • Pins: A0, RSV, SD3, SD5, SD1, CMD, D0-D8, RX, TX, Vin, 5V, 3V3, GND, CLK, RST, EN

Wiring Details

Temperature Sensor (LM35)

• +Vs connected to Arduino Mega 2560 5V
• Vout connected to Arduino Mega 2560 A1
• GND connected to Arduino Mega 2560 GND

HC-SR501 PIR Motion Sensor

• Power Supply connected to Arduino Mega 2560 D11 PWM
• Ground connected to Buzzer Negative, ESP-8266 Controller GND, Arduino Mega 2560 GND, LED Cathode, SIM900A GND
• Output connected to Capacitive Soil Moisture Sensor VCC, Arduino Mega 2560 5V, SIM900A VCC

Capacitive Soil Moisture Sensor V1.2

• GND connected to Arduino Mega 2560 GND, 12V Single Channel Relay GND
• VCC connected to HC-SR501 PIR Motion Sensor Output
• AOUT connected to Arduino Mega 2560 A0

LED: Two Pin (red)

• Cathode connected to HC-SR501 PIR Motion Sensor Ground
• Anode connected to Resistor (220 Ohms) Pin2

Resistor (220 Ohms)

• Pin1 connected to Arduino Mega 2560 D10 PWM
• Pin2 connected to LED Anode

Resistor (10k Ohms)

• Pin1 connected to Arduino Mega 2560 3V3
• Pin2 connected to ESP-8266 Controller EN

Arduino Mega 2560

• 3V3 connected to Resistor (10k Ohms) Pin1
• GND connected to Lipo Battery 2200mAH 30c GND, 5V Mini Water Pump Negative Pin, Temperature Sensor (LM35) GND, Capacitive Soil Moisture Sensor GND, 12V Single Channel Relay GND
• VIN connected to Lipo Battery 2200mAH 30c VCC
• A0 connected to Capacitive Soil Moisture Sensor AOUT
• A1 connected to Temperature Sensor (LM35) Vout
• D8 PWM connected to 12V Single Channel Relay IN
• D9 PWM connected to Buzzer Positive
• D10 PWM connected to Resistor (220 Ohms) Pin1
• D11 PWM connected to HC-SR501 PIR Motion Sensor Power Supply
• D16 PWM/TX2 connected to SIM900A DB9-3 (RXD)
• D17 PWM/RX2 connected to SIM900A DB9-2 (TXD)
• D18/TX1 connected to ESP-8266 Controller RX
• D19/RX1 connected to ESP-8266 Controller TX

5V Mini Water Pump

• Positive Pin connected to 12V Single Channel Relay NO
• Negative Pin connected to Arduino Mega 2560 GND

SIM900A

• GND connected to HC-SR501 PIR Motion Sensor Ground
• DB9-3 (RXD) connected to Arduino Mega 2560 D16 PWM/TX2
• DB9-2 (TXD) connected to Arduino Mega 2560 D17 PWM/RX2
• VCC connected to HC-SR501 PIR Motion Sensor Output

12V Single Channel Relay

• COM connected to Lipo Battery 2200mAH 30c VCC
• NO connected to 5V Mini Water Pump Positive Pin
• IN connected to Arduino Mega 2560 D8 PWM
• GND connected to Capacitive Soil Moisture Sensor GND
• VCC connected to Arduino Mega 2560 5V

Buzzer

• Positive connected to Arduino Mega 2560 D9 PWM
• Negative connected to HC-SR501 PIR Motion Sensor Ground

Lipo Battery 2200mAH 30c

• VCC connected to Arduino Mega 2560 VIN, 12V Single Channel Relay COM
• GND connected to Arduino Mega 2560 GND, 5V Mini Water Pump Negative Pin

ESP-8266 Controller

• TX connected to Arduino Mega 2560 D19/RX1
• RX connected to Arduino Mega 2560 D18/TX1
• GND connected to HC-SR501 PIR Motion Sensor Ground
• Vin connected to Temperature Sensor (LM35) +Vs
• EN connected to Resistor (10k Ohms) Pin2

Documented Code

/*
 * IoT-based Smart Agriculture System
 * This Arduino sketch automates farm management by monitoring environmental
 * conditions (temperature, soil moisture) and controlling irrigation using a
 * water pump. The system sends alerts and updates via a GSM module, enhancing
 * farm efficiency and sustainability with automated and remote monitoring.
 */

// Pin definitions
const int soilMoisturePin = A0;
const int tempSensorPin = A1;
const int relayPin = 8;
const int buzzerPin = 9;
const int ledPin = 10;
const int pirSensorPin = 11;
const int gsmTxPin = 16;
const int gsmRxPin = 17;
const int espTxPin = 18;
const int espRxPin = 19;

void setup() {
  // Initialize serial communication
  Serial.begin(9600);
  Serial1.begin(9600); // GSM module
  Serial2.begin(9600); // ESP8266

  // Initialize pins
  pinMode(soilMoisturePin, INPUT);
  pinMode(tempSensorPin, INPUT);
  pinMode(relayPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(pirSensorPin, INPUT);

  // Initial states
  digitalWrite(relayPin, LOW);
  digitalWrite(buzzerPin, LOW);
  digitalWrite(ledPin, LOW);
}

void loop() {
  // Read sensor values
  int soilMoisture = analogRead(soilMoisturePin);
  int tempValue = analogRead(tempSensorPin