Smart Farming System for ESP32

A comprehensive IoT-based smart farming solution that automates irrigation based on soil moisture, temperature, and humidity readings. The system supports both offline and online operation modes with modular display options and dual cloud service integration.

Project Structure

smart_farming/
├── MainCode/                    # Main smart farming system
│   ├── offline/                     # Offline version (standalone)
│   │   ├── offline.ino              # Main offline sketch
│   │   └── config.h                 # Offline configuration
│   ├── online/                      # Online version (IoT with cloud)
│   │   ├── online.ino               # Main online sketch
│   │   └── config.h                 # Online configuration
│   └── README.md                    # Main code documentation
├── TestCode/                    # Testing and validation
│   ├── hardware/                    # Hardware testing
│   │   ├── hardware_test.ino        # Comprehensive hardware test
│   │   └── README.md                # Hardware test documentation
│   └── communication/               # Communication testing
│       ├── communication.ino        # Communication test suite
│       └── README.md                # Communication test documentation
├── docs/                        # Web documentation
│   ├── index.html               # Main documentation page
│   ├── styles.css               # Custom CSS styles
│   ├── script.js                # Interactive JavaScript
│   └── README.md                # Documentation guide
├── configuration.md            # Comprehensive configuration guide
├── wiring_diagram.md           # Wiring instructions with Mermaid
├── libraries.txt              # Required Arduino libraries
├── LICENSE                     # MIT License
└── README.md                  # This file

Project Overview

This smart farming system is designed to automate irrigation processes while providing comprehensive monitoring capabilities. It combines local sensor data with cloud connectivity to create a robust, scalable solution for modern agriculture.

Key Benefits

Automated Irrigation: Intelligent watering based on soil moisture levels
Real-time Monitoring: Continuous sensor data collection and analysis
Cloud Integration: Data logging and remote monitoring via ThingSpeak and Adafruit IO
Modular Design: Flexible display options and configurable features
Fail-safe Operation: Built-in safety mechanisms and error recovery
Remote Control: Web-based interface for system management
OTA Updates: Over-the-air firmware updates for remote maintenance

Features

Core Functionality

Soil Moisture Monitoring: Analog sensor with configurable thresholds
Environmental Sensing: DHT11/DHT22 temperature and humidity monitoring
Light Level Monitoring: LDR sensor for ambient light detection
Automated Irrigation: Relay-controlled water pump with safety timers
Visual Feedback: LED status indicators and optional LCD displays
Data Logging: Comprehensive system state tracking

Online Version Features

WiFi Connectivity: Automatic connection and reconnection
Dual Cloud Services: ThingSpeak and Adafruit IO integration
Web Interface: Remote monitoring and control dashboard
OTA Updates: Over-the-air firmware updates
JSON API: RESTful API for system integration
Configurable Cloud Services: Enable/disable individual services

Safety & Reliability Features

Watchdog Timer: Prevents system hangs and crashes
Emergency Stop: Manual emergency shutdown capability
Pump Runtime Protection: Prevents pump damage from continuous operation
Sensor Validation: Range checking, consistency validation, and disconnection detection
Automatic Recovery: Self-healing after system errors
Error Logging: Comprehensive error tracking and reporting

Hardware Requirements

Essential Components

Component	Specification	Purpose	Notes
ESP32 Development Board	ESP32-WROOM-32 or similar	Main controller	Must support WiFi and ADC
Soil Moisture Sensor	Analog capacitive sensor	Soil moisture detection	0-3.3V output range
Relay Module	5V SPDT relay	Pump control	Must handle pump current
Water Pump	12V DC submersible	Irrigation	Match relay specifications
Power Supply	5V/3.3V adapter	System power	Minimum 2A capacity

Optional Components

Component	Specification	Purpose	Notes
DHT Sensor	DHT11 or DHT22	Temperature/humidity	Digital sensor with 1-wire protocol
LDR Sensor	Light Dependent Resistor	Ambient light detection	Analog sensor with voltage divider
LCD Display	1602 or 2004 I2C	Visual monitoring	Optional - see Display Options
LEDs	5mm standard	Status indication	Green, Red, Blue
Resistors	220Ω, 10kΩ	Current limiting	For LEDs and pull-ups
Breadboard	Half-size	Prototyping	For development
Jumper Wires	Male-to-male/female	Connections	Various lengths

Pin Connections

Component	ESP32 Pin	Notes	Alternative Pins
LCD SDA	GPIO 21	I2C Data (if display enabled)	GPIO 4, GPIO 16
LCD SCL	GPIO 22	I2C Clock (if display enabled)	GPIO 5, GPIO 17
DHT Data	GPIO 5	Digital input	GPIO 4, GPIO 18
Soil Moisture	GPIO 36	Analog input (ADC1_CH0)	GPIO 39, GPIO 34
Relay Control	GPIO 19	Digital output	GPIO 18, GPIO 23
Green LED	GPIO 18	Status indicator	GPIO 2, GPIO 4
Red LED	GPIO 23	Pump active indicator	GPIO 2, GPIO 4
Blue LED	GPIO 2	WiFi status (online version)	GPIO 4, GPIO 5
Emergency Stop	GPIO 0	Optional emergency button	GPIO 35, GPIO 34
Control System
Rotary Encoder CLK	GPIO 16	Clock pin (if encoder enabled)	GPIO 4, GPIO 5
Rotary Encoder DT	GPIO 17	Data pin (if encoder enabled)	GPIO 4, GPIO 5
Rotary Encoder SW	GPIO 4	Switch/Button pin (if encoder)	GPIO 0, GPIO 35
Potentiometer	GPIO 34	Analog input (if pot enabled)	GPIO 35, GPIO 36

Installation Guide

Step 1: Software Setup

Arduino IDE Installation

Download Arduino IDE (version 1.8.19 or later)
- Official Arduino IDE
- Arduino IDE 2.0 (recommended)

Install ESP32 Board Support

# Add ESP32 board URL to Arduino IDE:
# File → Preferences → Additional Board Manager URLs
https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

Then install ESP32 board package:

Tools → Board → Boards Manager
Search for "ESP32"
Install "ESP32 by Espressif Systems"

Install Required Libraries

# Install libraries via Arduino IDE Library Manager:
# Tools → Manage Libraries → Search and install:

- DHT sensor library (by Adafruit) v1.4.4+
- LiquidCrystal I2C (by Frank de Brabander) v1.1.2+
- ArduinoJson (by Benoit Blanchon) v6.19.4+
- Adafruit IO Arduino (by Adafruit) v5.0.0+

PlatformIO Installation (Alternative)

# platformio.ini configuration
[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
lib_deps = 
    adafruit/DHT sensor library@^1.4.4
    marcoschwartz/LiquidCrystal_I2C@^1.1.2
    bblanchon/ArduinoJson@^6.19.4
    adafruit/Adafruit IO Arduino@^5.0.0

Step 2: Arduino IDE Project Structure

The project is organized to work seamlessly with Arduino IDE's expected structure:

Opening Projects in Arduino IDE

Main Applications:
- Offline Version: Open MainCode/offline/offline.ino for standalone operation
- Online Version: Open MainCode/online/online.ino for IoT operation with cloud connectivity
Test Applications:
- Hardware Test: Open TestCode/hardware/hardware_test.ino to validate all hardware components
- Communication Test: Open TestCode/communication/communication.ino to test WiFi, cloud services, and web server
Configuration Files:
- Each sketch has its own config.h file for easy customization
- Configuration is modular and version-specific

Arduino IDE Workflow

Select Board: ESP32 Dev Module
Select Port: Your ESP32's COM port
Open Sketch: Choose the appropriate .ino file
Configure: Edit config.h if needed
Compile: Verify code compiles without errors
Upload: Flash to ESP32

Step 3: Hardware Assembly

Basic Wiring Diagram

ESP32                    Components
├── GPIO 21 ──────────── LCD SDA (I2C) - Optional
├── GPIO 22 ──────────── LCD SCL (I2C) - Optional
├── GPIO 5 ───────────── DHT Data Pin - Optional
├── GPIO 36 ──────────── Soil Moisture Sensor (Analog) - Required
├── GPIO 39 ──────────── LDR Sensor (Analog) - Optional
├── GPIO 19 ──────────── Relay Control Pin - Required
├── GPIO 18 ──────────── Green LED (220Ω resistor) - Optional
├── GPIO 23 ──────────── Red LED (220Ω resistor) - Optional
├── GPIO 2 ───────────── Blue LED (220Ω resistor) - Optional
├── 3.3V ─────────────── Sensor VCC, Relay VCC
├── GND ──────────────── Common Ground
└── 5V ───────────────── Relay VCC (if 5V relay)

Detailed Wiring Instructions

Power Connections
- Connect ESP32 3.3V to sensor VCC pins
- Connect ESP32 GND to all component ground pins
- Use external 5V supply for relay if needed
Sensor Connections
- Soil Moisture: Signal to GPIO 36, VCC to 3.3V, GND to ground (Required)
- DHT Sensor: Data pin to GPIO 5, VCC to 3.3V, GND to ground (Optional)
- LDR Sensor: Signal to GPIO 39, VCC to 3.3V, GND to ground (with 10kΩ pull-down resistor) (Optional)
Display Connections (if using LCD)
- LCD I2C: SDA to GPIO 21, SCL to GPIO 22, VCC to 3.3V, GND to ground
Actuator Connections
- Relay: Control pin to GPIO 19, VCC to 5V, GND to ground
- Pump: Connect to relay NO (Normally Open) terminal
Status LEDs
- Green LED: Anode to GPIO 18, Cathode to ground (via 220Ω resistor)
- Red LED: Anode to GPIO 23, Cathode to ground (via 220Ω resistor)
- Blue LED: Anode to GPIO 2, Cathode to ground (via 220Ω resistor)

Step 3: Code Upload

Download Project Files

git clone <repository-url>
cd smart_farming

Configure System
- Edit config.h with your specific settings
- Choose display type and cloud services
- Set WiFi credentials (online version)
Upload Code
- Select ESP32 board: Tools → Board → ESP32 Arduino → ESP32 Dev Module
- Select COM port: Tools → Port → [Your ESP32 Port]
- Upload: Sketch → Upload

Configuration Guide

📋 For a comprehensive configuration guide with detailed comparisons, pros/cons, and recommended setups, see configuration.md

Basic Configuration (`config.h`)

System Settings

// System Operation Mode
#define DEBUG_MODE true                    // Enable debug output
#define SERIAL_BAUD_RATE 115200           // Serial communication speed

// Timing Configuration
#define SENSOR_READ_INTERVAL 2000         // Sensor reading interval (ms)
#define IRRIGATION_DURATION 10000         // Irrigation duration (ms)
#define MIN_IRRIGATION_INTERVAL 300000    // Minimum time between irrigations (ms)

Sensor Configuration

// Soil Moisture Sensor
#define SOIL_MOISTURE_THRESHOLD 30        // Irrigation threshold (%)
#define SOIL_MOISTURE_WET_VALUE 4095      // Wet reading (in water)
#define SOIL_MOISTURE_DRY_VALUE 0         // Dry reading (in air)

// DHT Sensor
#define DHT_TYPE DHT22                    // DHT11 or DHT22
#define DHT_READ_INTERVAL 2000           // DHT reading interval (ms)

// LDR Sensor (Optional)
#define LDR_SENSOR_TYPE LDR_NONE         // LDR_NONE or LDR_ENABLED
#define LDR_DARK_VALUE 4095              // Dark reading (complete darkness)
#define LDR_BRIGHT_VALUE 0               // Bright reading (full light)
#define LDR_LOW_LIGHT_THRESHOLD 20       // Low light threshold (%)
#define LDR_HIGH_LIGHT_THRESHOLD 80      // High light threshold (%)

Display Configuration

// Display Type Selection
#define DISPLAY_TYPE DISPLAY_LCD_1602     // Options: DISPLAY_NONE, DISPLAY_LCD_1602, DISPLAY_LCD_2004

// Display Settings
#define DISPLAY_UPDATE_INTERVAL 1000      // Display update interval (ms)
#define DISPLAY_SCROLL_DELAY 2000         // Screen cycling delay (ms)
#define SERIAL_OUTPUT_ENABLED true        // Enable serial output

// Control Type Selection
#define CONTROL_TYPE CONTROL_ROTARY_ENCODER  // Options: CONTROL_NONE, CONTROL_POTENTIOMETER, CONTROL_ROTARY_ENCODER

// Control Settings
#define MENU_TIMEOUT 30000               // Menu timeout (ms) - Rotary Encoder
#define ENCODER_STEP_SIZE 1              // Step size for parameter adjustment
#define POTENTIOMETER_UPDATE_INTERVAL 500 // Update interval (ms) - Potentiometer

Advanced Configuration

Safety & Fail-safe Mechanisms

// Watchdog Timer
#define WATCHDOG_TIMEOUT 30               // Watchdog timeout (seconds)
#define WATCHDOG_ENABLED true             // Enable watchdog timer

// Emergency Stop
#define EMERGENCY_STOP_ENABLED true       // Enable emergency stop
#define EMERGENCY_STOP_PIN 0              // Emergency stop button pin

// Pump Protection
#define MAX_PUMP_RUNTIME 300000           // Maximum pump runtime (ms)
#define PUMP_RUNTIME_PROTECTION true      // Enable pump protection

// System Recovery
#define AUTO_RECOVERY_ENABLED true        // Enable automatic recovery
#define RECOVERY_ATTEMPTS 3               // Maximum recovery attempts
#define RECOVERY_DELAY 5000               // Recovery delay (ms)

Sensor Validation

// Temperature Validation
#define MIN_TEMPERATURE -10.0             // Minimum valid temperature (°C)
#define MAX_TEMPERATURE 60.0              // Maximum valid temperature (°C)
#define TEMPERATURE_VALIDATION true        // Enable temperature validation

// Humidity Validation
#define MIN_HUMIDITY 0.0                  // Minimum valid humidity (%)
#define MAX_HUMIDITY 100.0                // Maximum valid humidity (%)
#define HUMIDITY_VALIDATION true          // Enable humidity validation

// Soil Moisture Validation
#define MIN_SOIL_MOISTURE 0               // Minimum valid soil moisture (%)
#define MAX_SOIL_MOISTURE 100             // Maximum valid soil moisture (%)
#define SOIL_MOISTURE_VALIDATION true     // Enable soil moisture validation
#define MAX_SOIL_MOISTURE_CHANGE 20       // Maximum change between readings (%)

// Sensor Consistency
#define SENSOR_CONSISTENCY_CHECKS 3       // Readings for consistency check
#define SENSOR_CONSISTENCY_THRESHOLD 5    // Maximum deviation for consistent readings
#define CONSISTENCY_VALIDATION true       // Enable consistency validation

// Disconnection Detection
#define SENSOR_DISCONNECT_THRESHOLD 10    // Readings before marking disconnected
#define DISCONNECT_DETECTION true         // Enable disconnection detection

Display Options

The system supports three display configurations for maximum flexibility:

1. LCD 1602 (16x2 characters) - Default

Configuration: #define DISPLAY_TYPE DISPLAY_LCD_1602
Features:
- Cycling screens (3 screens)
- Sensor data, system status, irrigation info
- Compact 2-line display
- Automatic screen cycling
Best for: Basic monitoring, compact installations, educational projects
Wiring: I2C connection to GPIO 21 (SDA) and GPIO 22 (SCL)

Screen Layout:

Screen 1: Temperature & Humidity → Soil Moisture
Screen 2: System Status → Pump Status & Daily Count
Screen 3: Irrigation Info → Last Irrigation Time

2. LCD 2004 (20x4 characters) - Enhanced

Configuration: #define DISPLAY_TYPE DISPLAY_LCD_2004
Features:
- Single screen with all information
- 4 lines of comprehensive data
- Temperature, humidity, soil moisture, pump status
- System status, WiFi status, daily irrigations
- Cloud service status (online version)
Best for: Professional installations, detailed monitoring, control rooms
Wiring: I2C connection to GPIO 21 (SDA) and GPIO 22 (SCL)

Screen Layout:

Line 1: T:25.3C H:65.2% Soil:45% Pump:OFF
Line 2: Status:OK WiFi:ON Errors:0
Line 3: Daily:3 TS:ON AIO:ON
Line 4: Up:60m Last:120s

3. No Display - Headless Mode

Configuration: #define DISPLAY_TYPE DISPLAY_NONE
Features:
- Serial output only
- Web interface (online version)
- Comprehensive status logging
- Lower power consumption
- Smaller footprint
Best for: Remote installations, cost optimization, IoT deployments, automated systems

Control Options

The system supports three control configurations for maximum flexibility:

1. Rotary Encoder - Advanced Control (Default)

Configuration: #define CONTROL_TYPE CONTROL_ROTARY_ENCODER
Features:
- Interactive menu system
- Real-time parameter adjustment
- Push button for menu navigation
- Rotary dial for value changes
- Menu timeout protection
Best for: Professional installations, user-friendly operation
Wiring: CLK (GPIO 16), DT (GPIO 17), SW (GPIO 4)

Menu System

Soil Threshold: Adjust irrigation trigger point (10-80%)
Irrigation Time: View current irrigation duration
Display Speed: View current display update speed
System Status: View system health (offline) / WiFi Status (online)
Save & Exit: Save settings and return to normal operation

2. Potentiometer - Simple Control

Configuration: #define CONTROL_TYPE CONTROL_POTENTIOMETER
Features:
- Real-time threshold adjustment
- Analog control (0-100%)
- Visual feedback on display
- Smooth value changes
Best for: Simple installations, basic threshold adjustment
Wiring: Center pin to GPIO 34, outer pins to 3.3V and GND

3. No Control - Fully Automated

Configuration: #define CONTROL_TYPE CONTROL_NONE
Features:
- Fully automated operation
- No manual intervention needed
- Uses default thresholds
- Clean, minimal interface
Best for: Set-and-forget installations, remote monitoring
Benefits:
- Lower cost
- Simpler wiring
- Reduced complexity
- Reduced power consumption
- Smaller physical footprint
- Ideal for hidden installations

Display Configuration Examples

For Basic Home Garden Setup

#define DISPLAY_TYPE DISPLAY_LCD_1602
#define DISPLAY_SCROLL_DELAY 3000        // Slower cycling for easy reading
#define SERIAL_OUTPUT_ENABLED true       // Keep serial for debugging

For Professional Farm Installation

#define DISPLAY_TYPE DISPLAY_LCD_2004
#define DISPLAY_UPDATE_INTERVAL 500      // Faster updates
#define SERIAL_OUTPUT_ENABLED true       // Logging for maintenance

For Remote IoT Deployment

#define DISPLAY_TYPE DISPLAY_NONE
#define SERIAL_OUTPUT_ENABLED true       // Essential for remote monitoring
#define DEBUG_MODE false                 // Reduce serial output

Cloud Services Setup

ThingSpeak Configuration

Step 1: Create ThingSpeak Account

Visit ThingSpeak.com
Sign up for a free account
Verify your email address

Step 2: Create Channel

Click "New Channel"

Configure channel settings:

Name: Smart Farming System
Description: ESP32-based irrigation control
Field 1: Temperature (°C)
Field 2: Humidity (%)
Field 3: Soil Moisture (%)
Field 4: Pump Status (0/1)
Field 5: Daily Irrigations
Field 6: System Errors
Field 7: WiFi Signal Strength
Field 8: Uptime (minutes)

Save channel and note the Channel ID

Step 3: Get API Key

Go to "API Keys" tab
Copy the "Write API Key"

Update config.h:

#define THINGSPEAK_ENABLED true
#define THINGSPEAK_API_KEY "YOUR_WRITE_API_KEY"
#define THINGSPEAK_CHANNEL_ID 1234567

Adafruit IO Configuration

Step 1: Create Adafruit IO Account

Visit Adafruit IO
Sign up for a free account
Verify your email address

Step 2: Create Feeds

Create the following feeds:

temperature (Number feed)
humidity (Number feed)
soil-moisture (Number feed)
pump-status (Number feed)
irrigation-count (Number feed)
system-status (Number feed)
sensor-errors (Number feed)

Step 3: Get Credentials

Go to "Adafruit IO Key" section
Copy your Username and Active Key

Update config.h:

#define ADAFRUIT_IO_ENABLED true
#define ADAFRUIT_IO_USERNAME "your_username"
#define ADAFRUIT_IO_KEY "your_active_key"

Cloud Service Options

ThingSpeak Only

#define THINGSPEAK_ENABLED true
#define ADAFRUIT_IO_ENABLED false

Adafruit IO Only

#define THINGSPEAK_ENABLED false
#define ADAFRUIT_IO_ENABLED true

Both Services (Redundancy)

#define THINGSPEAK_ENABLED true
#define ADAFRUIT_IO_ENABLED true

Offline Mode

#define THINGSPEAK_ENABLED false
#define ADAFRUIT_IO_ENABLED false

Usage Guide

Offline Mode Operation

Initial Setup

Power On: Connect power supply to ESP32
Serial Monitor: Open Arduino IDE Serial Monitor (115200 baud)
System Check: Verify all sensors are detected
Calibration: Test soil moisture sensor in air and water

Daily Operation

Monitoring: Check LCD display or serial output
Status LEDs:
- Green: System OK
- Red: Pump active or error
- Blue: Not used in offline mode
Automatic Irrigation: System waters when soil moisture < threshold
Manual Override: Use emergency stop if needed

Maintenance

Weekly: Check sensor readings and pump operation
Monthly: Clean sensors and check connections
Seasonally: Recalibrate soil moisture sensor

Online Mode Operation

Initial Setup

WiFi Configuration: Update WiFi credentials in config.h
Cloud Setup: Configure ThingSpeak and/or Adafruit IO
Upload Code: Flash ESP32 with online version
Network Test: Verify WiFi connection and cloud data transmission

Web Interface Access

Find IP Address: Check serial output for assigned IP
Open Browser: Navigate to http://[ESP32_IP]
Dashboard: View real-time sensor data and system status
Control: Start/stop irrigation manually
Settings: Adjust thresholds and intervals

Remote Monitoring

ThingSpeak Dashboard: View historical data and charts
Adafruit IO Dashboard: Monitor feeds and create alerts
Mobile Access: Use mobile browsers for remote monitoring
API Integration: Use JSON API for custom applications

Display Modes

LCD 1602 Operation

Automatic Cycling: Screens change every 2 seconds
Information Displayed:
- Temperature and humidity
- Soil moisture percentage
- System status (OK/ERROR)
- Pump status (ON/OFF)
- Daily irrigation count
- Last irrigation time

LCD 2004 Operation

Static Display: All information visible simultaneously
Information Displayed:
- Line 1: Temperature, humidity, soil moisture, pump status
- Line 2: System status, WiFi status, error count
- Line 3: Daily irrigations, cloud service status
- Line 4: Uptime, last irrigation time

Headless Mode Operation

Serial Output: Comprehensive status every second
Web Interface: Full dashboard (online version)
API Access: JSON endpoints for integration
Logging: Detailed system logs for troubleshooting

Control Modes

Rotary Encoder Operation

Menu Navigation:
- Press button to enter menu mode
- Rotate encoder to navigate through menu items
- Press button to select item or enter parameter adjustment
Parameter Adjustment:
- Rotate encoder to increase/decrease values
- Real-time display of current setting
- Automatic save when exiting menu
Menu Items:
- Soil Threshold (10-80%)
- Irrigation Time (view only)
- Display Speed (view only)
- System Status (view only)
- Save & Exit

Potentiometer Operation

Real-time Control:
- Turn knob to adjust irrigation threshold
- Immediate effect on system behavior
- Visual feedback on display
Range: 10-80% soil moisture threshold
Update Rate: Every 500ms for smooth operation

No Control Operation

Fully Automated:
- Uses default soil moisture threshold (30%)
- No manual intervention required
- Ideal for remote installations
Benefits:
- Lower cost
- Simpler wiring
- Reduced complexity

Advanced Features

Fail-safe Mechanisms

Watchdog Timer

Purpose: Prevents system hangs and crashes
Configuration: 30-second timeout (configurable)
Operation: Automatically resets system if main loop stops
Benefits: Ensures continuous operation in field conditions

Emergency Stop

Purpose: Immediate system shutdown capability
Implementation: GPIO pin monitoring for emergency button
Safety: Stops irrigation immediately when activated
Recovery: Requires manual reset after emergency stop

Pump Runtime Protection

Purpose: Prevents pump damage from continuous operation
Configuration: Maximum 5-minute runtime (configurable)
Safety: Automatic shutdown if runtime exceeded
Monitoring: Tracks pump start time and duration

Automatic System Recovery

Purpose: Self-healing after system errors
Implementation: Automatic sensor reinitialization
Recovery: Up to 3 recovery attempts with delays
Logging: Records recovery attempts and success/failure

Sensor Validation System

Range Validation

Temperature: -10°C to 60°C (configurable)
Humidity: 0% to 100%
Soil Moisture: 0% to 100%
Purpose: Prevents erroneous readings from affecting irrigation

Consistency Validation

Method: Compares current reading with recent history
Threshold: 5% maximum deviation (configurable)
Checks: 3 consecutive readings for consistency
Benefits: Filters out sensor noise and temporary errors

Sudden Change Detection

Soil Moisture: Maximum 20% change between readings
Purpose: Detects sensor disconnection or malfunction
Response: Marks reading as invalid, increments error counter
Recovery: Automatic sensor reinitialization

Disconnection Detection

Method: Tracks consecutive invalid readings
Threshold: 10 consecutive errors (configurable)
Response: Marks sensor as disconnected
Recovery: Attempts automatic reconnection

OTA (Over-the-Air) Updates

Setup

// In config.h
#define OTA_ENABLED true
#define OTA_HOSTNAME "smart-farming-esp32"
#define OTA_PASSWORD "your_ota_password"

Usage

Upload Initial Code: Include OTA functionality
Network Access: Ensure ESP32 is on WiFi network
Arduino IDE: Use "Upload via Network" option
Remote Updates: Update firmware without physical access

Benefits

Remote Maintenance: Update firmware from anywhere
No Physical Access: Ideal for remote installations
Rollback Capability: Revert to previous version if needed
Version Tracking: Monitor firmware versions remotely

Web Server Features

Dashboard Interface

Real-time Data: Live sensor readings and system status
Control Panel: Manual irrigation start/stop
Settings: Adjustable thresholds and intervals
Status Indicators: Visual system health indicators

JSON API Endpoints

// Get system status
GET /api/status
Response: {
  "temperature": 25.3,
  "humidity": 65.2,
  "soilMoisture": 45,
  "pumpActive": false,
  "systemOK": true,
  "wifiConnected": true,
  "dailyIrrigations": 3,
  "sensorErrors": 0,
  "uptime": 3600
}

// Start irrigation
POST /api/irrigation/start
Response: {"success": true, "message": "Irrigation started"}

// Stop irrigation
POST /api/irrigation/stop
Response: {"success": true, "message": "Irrigation stopped"}

Mobile Responsiveness

Responsive Design: Works on phones and tablets
Touch Controls: Easy mobile interaction
Offline Capability: Works without internet connection
Progressive Web App: Can be installed on mobile devices

Troubleshooting

Common Issues and Solutions

Display Problems

LCD not displaying

Check: I2C connections (SDA/SCL)
Verify: LCD address (usually 0x27 or 0x3F)
Solution: Use I2C scanner to find correct address
Config: Ensure DISPLAY_TYPE matches your hardware

LCD shows garbled text

Check: Power supply voltage (3.3V or 5V)
Verify: Contrast adjustment on LCD
Solution: Check wiring and power connections

LCD backlight not working

Check: Backlight power connection
Verify: Backlight control in code
Solution: Ensure proper I2C backpack connection

Sensor Issues

DHT sensor not reading

Check: Data pin connection (GPIO 5)
Verify: Power supply (3.3V)
Solution: Test with simple DHT example code
Alternative: Try different GPIO pin

Soil moisture sensor readings erratic

Check: Analog pin connection (GPIO 36)
Verify: Power supply stability
Solution: Add capacitor for power filtering
Calibration: Test in air (dry) and water (wet)

Sensor validation errors

Check: Sensor range settings in config.h
Verify: Physical sensor condition
Solution: Adjust validation thresholds
Recovery: Enable automatic recovery in config

Network Issues

WiFi not connecting

Check: WiFi credentials in config.h
Verify: Signal strength and network availability
Solution: Test with simple WiFi example
Alternative: Use mobile hotspot for testing

Cloud data not transmitting

Check: API keys and channel IDs
Verify: Internet connectivity
Solution: Test cloud services individually
Debug: Enable debug mode for detailed logs

Web interface not accessible

Check: ESP32 IP address in serial output
Verify: Same network as ESP32
Solution: Try different browser or clear cache
Alternative: Use IP address instead of hostname

System Performance Issues

System hangs or crashes

Check: Watchdog timer configuration
Verify: Power supply stability
Solution: Enable watchdog timer
Debug: Monitor serial output for error patterns

Pump not responding

Check: Relay connections and power
Verify: Pump power supply
Solution: Test relay with simple on/off code
Safety: Check pump runtime protection settings

Memory issues

Check: Available heap memory in serial output
Verify: Library versions and compatibility
Solution: Update to latest library versions
Optimization: Reduce debug output or disable unused features

Calibration Procedures

Soil Moisture Sensor Calibration

Dry Calibration: Place sensor in air, record reading
Wet Calibration: Place sensor in water, record reading
Update Config: Set SOIL_MOISTURE_DRY_VALUE and SOIL_MOISTURE_WET_VALUE
Test: Verify readings match expected percentages

DHT Sensor Calibration

Temperature: Compare with known thermometer
Humidity: Compare with hygrometer
Offset: Apply calibration offsets if needed
Validation: Enable sensor validation for error detection

System Timing Calibration

Sensor Intervals: Adjust based on required response time
Irrigation Duration: Test actual watering time needed
Display Updates: Balance between responsiveness and power consumption
Cloud Transmission: Optimize for data usage and reliability

Debugging Techniques

Serial Monitor Usage

// Enable debug mode
#define DEBUG_MODE true

// Monitor system output
Serial.println("System Status: " + String(systemOK ? "OK" : "ERROR"));
Serial.println("Sensor Errors: " + String(sensorErrors));
Serial.println("Free Heap: " + String(ESP.getFreeHeap()));

LED Status Indicators

Green LED: System OK, sensors reading normally
Red LED: Pump active or system error
Blue LED: WiFi connected (online version)
Blinking Patterns: Different error conditions

Web Interface Debugging

Status Page: Real-time system information
Logs: Historical error and event logs
Settings: Current configuration values
Test Functions: Manual sensor and actuator testing

Safety & Best Practices

Electrical Safety

Power Supply Considerations

Voltage: Use appropriate voltage for each component
Current: Ensure sufficient current capacity (minimum 2A)
Protection: Use fuses or circuit breakers for protection
Grounding: Proper grounding for safety

Wiring Safety

Insulation: Use proper insulated wires
Connections: Secure all connections to prevent shorts
Protection: Use enclosures for outdoor installations
Moisture: Protect connections from water damage

Operational Safety

Pump Safety

Runtime Limits: Never exceed maximum pump runtime
Power Supply: Ensure adequate power for pump operation
Protection: Use appropriate relay ratings for pump current
Monitoring: Watch for pump overheating or unusual noise

System Safety

Emergency Stop: Always provide emergency stop capability
Fail-safe: Design for safe failure modes
Monitoring: Regular system health checks
Backup: Manual override capability for critical functions

Environmental Considerations

Outdoor Installation

Weatherproofing: Protect electronics from weather
Temperature: Consider operating temperature range
Moisture: Protect from rain and humidity
Sunlight: Shield from direct sunlight

Maintenance Access

Location: Install in accessible location for maintenance
Documentation: Keep wiring diagrams and configuration records
Spare Parts: Keep critical spare parts available
Testing: Regular system testing and calibration

Data Security

Network Security

WiFi: Use strong passwords and WPA2/WPA3 encryption
OTA: Use strong OTA passwords
API: Implement API authentication if needed
Updates: Keep firmware updated for security patches

Data Privacy

Cloud Services: Understand data storage and privacy policies
Local Data: Secure local data storage
Access Control: Limit access to system controls
Monitoring: Monitor for unauthorized access

Performance Optimization

Power Management

Sleep Modes

// Deep sleep between readings (advanced)
esp_deep_sleep_start();

// Light sleep for power saving
esp_light_sleep_start();

Component Optimization

Display: Reduce update frequency for power saving
Sensors: Optimize reading intervals
WiFi: Use power save mode when possible
CPU: Reduce clock speed for lower power consumption

Memory Optimization

RAM Usage

// Monitor heap usage
Serial.println("Free Heap: " + String(ESP.getFreeHeap()));

// Use PROGMEM for constants
const char PROGMEM statusMessage[] = "System OK";

Flash Usage

Libraries: Use only required libraries
Features: Disable unused features
Debug: Remove debug code in production
Optimization: Use compiler optimization flags

Network Optimization

WiFi Efficiency

// WiFi power save mode
WiFi.setSleep(true);

// Optimize connection parameters
WiFi.setAutoReconnect(true);
WiFi.setAutoConnect(true);

Data Transmission

Compression: Compress data before transmission
Batching: Send multiple readings together
Frequency: Optimize transmission intervals
Retry Logic: Implement efficient retry mechanisms

System Performance

Timing Optimization

Intervals: Balance responsiveness with efficiency
Priorities: Prioritize critical functions
Scheduling: Use efficient task scheduling
Interrupts: Use interrupts for time-critical functions

Error Handling

Recovery: Fast error recovery mechanisms
Logging: Efficient error logging
Monitoring: Proactive system monitoring
Prevention: Prevent errors through validation

Development Guide

Customization Options

Adding New Sensors

// Example: Adding a light sensor
#define LIGHT_SENSOR_PIN 39
#define LIGHT_THRESHOLD 500

void readLightSensor() {
  int lightValue = analogRead(LIGHT_SENSOR_PIN);
  // Process light reading
}

Custom Display Layouts

void customDisplayLayout() {
  #if DISPLAY_TYPE == DISPLAY_LCD_2004
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Custom Layout");
    // Add custom display logic
  #endif
}

Additional Cloud Services

// Example: Adding MQTT support
#include <PubSubClient.h>

void publishToMQTT() {
  // MQTT publishing logic
}

Extending Functionality

New Irrigation Modes

// Example: Scheduled irrigation
void scheduledIrrigation() {
  // Check time-based irrigation
  if (hour() == 6 && minute() == 0) { // 6:00 AM
    startIrrigation();
  }
}

Advanced Analytics

// Example: Data analysis
void analyzeTrends() {
  // Analyze sensor data trends
  // Predict irrigation needs
  // Optimize watering schedule
}

Integration with Other Systems

// Example: Weather API integration
void checkWeatherForecast() {
  // Get weather data
  // Adjust irrigation based on forecast
}

Code Structure

Modular Design

Configuration: Centralized in config.h
Functions: Organized by functionality
Libraries: Separated by purpose
Documentation: Comprehensive code comments

Best Practices

Naming: Use descriptive variable and function names
Comments: Document complex logic
Error Handling: Comprehensive error handling
Testing: Test individual components

Contributing Guidelines

Code Standards

Formatting: Follow Arduino coding standards
Documentation: Document all functions and variables
Testing: Test changes thoroughly
Compatibility: Ensure backward compatibility

Pull Request Process

Fork: Fork the repository
Branch: Create feature branch
Develop: Implement changes with tests
Document: Update documentation
Submit: Submit pull request with description

FAQ

General Questions

Q: Can I use this system without any display? A: Yes! Set DISPLAY_TYPE to DISPLAY_NONE for headless operation. The system will work perfectly with just serial output and web interface (online version).

Q: What's the difference between offline and online versions? A: Offline version works standalone with local monitoring. Online version adds WiFi connectivity, cloud data logging, web interface, and OTA updates.

Q: Can I use both ThingSpeak and Adafruit IO simultaneously? A: Yes! The system supports dual cloud services for redundancy. Enable both in config.h for maximum reliability.

Q: How long can the system run without maintenance? A: With proper setup, the system can run for months. Regular maintenance includes checking sensors, cleaning connections, and monitoring system health.

Hardware Questions

Q: Can I use a different ESP32 board? A: Yes, any ESP32 board with WiFi and ADC support will work. Adjust pin assignments in config.h if needed.

Q: What if my LCD has a different I2C address? A: Use an I2C scanner to find your LCD's address, then update LCD_ADDRESS in config.h.

Q: Can I use a 5V relay instead of 3.3V? A: Yes, but you'll need a 5V power supply for the relay. The ESP32 GPIO pins are 3.3V, so ensure compatibility.

Q: What pump should I use? A: Any 12V DC submersible pump that matches your relay's current rating. Consider flow rate and pressure requirements for your application.

Software Questions

Q: How do I update the firmware remotely? A: Use the OTA (Over-the-Air) update feature in the online version. Upload code via Arduino IDE's "Upload via Network" option.

Q: Can I customize the web interface? A: Yes! The web interface is built with HTML/CSS/JavaScript. Modify the web server code to customize the interface.

Q: How do I add more sensors? A: Add sensor code to the appropriate functions, update config.h with new pin definitions, and modify the display and cloud transmission functions.

Q: Can I integrate this with home automation systems? A: Yes! Use the JSON API endpoints to integrate with systems like Home Assistant, OpenHAB, or custom automation scripts.

Troubleshooting Questions

Q: My sensors aren't reading correctly. What should I check? A: Check wiring connections, power supply voltage, sensor calibration, and validation settings in config.h.

Q: The system keeps restarting. What's wrong? A: Check power supply stability, enable watchdog timer, review error logs, and ensure proper grounding.

Q: Cloud data isn't transmitting. How do I debug? A: Check WiFi connection, API keys, internet connectivity, and enable debug mode to see detailed transmission logs.

Q: The pump isn't turning on. What should I check? A: Verify relay connections, pump power supply, relay control pin, and check for safety mechanisms that might be preventing operation.

Performance Questions

Q: How can I reduce power consumption? A: Use headless mode, increase sensor reading intervals, enable WiFi power save mode, and use deep sleep between operations.

Q: Can I run multiple systems on the same network? A: Yes, but ensure each system has a unique hostname and consider using different cloud channels for data separation.

Q: How much data does the system use? A: Depends on transmission frequency. Typical usage is 1-5MB per month for basic monitoring with 15-minute intervals.

Q: What's the maximum range for the WiFi connection? A: Depends on your router and environment. Typical range is 50-100 meters indoors, 100-300 meters outdoors with good antennas.

Contributing

We welcome contributions to improve the Smart Farming System! Here's how you can help:

Ways to Contribute

Code Contributions

Bug Fixes: Report and fix bugs
New Features: Add new functionality
Optimizations: Improve performance and efficiency
Documentation: Improve code documentation

Documentation Improvements

Tutorials: Create step-by-step guides
Examples: Provide usage examples
Translations: Translate documentation to other languages
Video Guides: Create video tutorials

Testing and Feedback

Testing: Test on different hardware configurations
Feedback: Report issues and suggest improvements
Use Cases: Share your implementation stories
Performance: Report performance characteristics

Development Setup

Prerequisites

Arduino IDE or PlatformIO
ESP32 development board
Required libraries (see libraries.txt)
Git for version control

Getting Started

Fork the repository
Clone your fork locally
Create a feature branch
Make your changes
Test thoroughly
Submit a pull request

Code Guidelines

Style Guidelines

Follow Arduino coding standards
Use meaningful variable and function names
Comment complex logic
Keep functions focused and small

Testing Requirements

Test on actual hardware
Verify all configurations work
Test error conditions
Ensure backward compatibility

Documentation Requirements

Update README for new features
Document configuration options
Provide usage examples
Include troubleshooting information

Community

Getting Help

Issues: Use GitHub issues for bug reports
Discussions: Use GitHub discussions for questions
Wiki: Check the wiki for additional documentation
Examples: Look at example implementations

Sharing Your Work

Showcase: Share your implementations
Tutorials: Create tutorials for others
Improvements: Suggest system improvements
Feedback: Provide feedback on the project

License

This project is open source and available under the MIT License. See the LICENSE file for details.

Acknowledgments

ESP32 Community: For excellent documentation and support
Arduino Community: For the platform and libraries
Sensor Manufacturers: For reliable sensor components
Open Source Contributors: For the libraries and tools used

Happy Farming!

For questions, issues, or contributions, please visit our GitHub repository.

Name		Name	Last commit message	Last commit date
Latest commit History 8 Commits
MainCode		MainCode
TestCode		TestCode
docs		docs
.gitignore		.gitignore
LICENSE		LICENSE
README.md		README.md
configuration.md		configuration.md
libraries.txt		libraries.txt
wiring_diagram.md		wiring_diagram.md

License

lily-osp/smart-farming-esp32

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Smart Farming System for ESP32

Table of Contents

Project Structure

Project Overview

Key Benefits

Features

Core Functionality

Online Version Features

Safety & Reliability Features

Hardware Requirements

Essential Components

Optional Components

Pin Connections

Installation Guide

Step 1: Software Setup

Arduino IDE Installation

PlatformIO Installation (Alternative)

Step 2: Arduino IDE Project Structure

Opening Projects in Arduino IDE

Arduino IDE Workflow

Step 3: Hardware Assembly

Basic Wiring Diagram

Detailed Wiring Instructions

Step 3: Code Upload

Configuration Guide

Basic Configuration (config.h)

System Settings

Sensor Configuration

Display Configuration

Advanced Configuration

Safety & Fail-safe Mechanisms

Sensor Validation

Display Options

1. LCD 1602 (16x2 characters) - Default

2. LCD 2004 (20x4 characters) - Enhanced

3. No Display - Headless Mode

Control Options

1. Rotary Encoder - Advanced Control (Default)

Menu System

2. Potentiometer - Simple Control

3. No Control - Fully Automated

Display Configuration Examples

For Basic Home Garden Setup

For Professional Farm Installation

For Remote IoT Deployment

Cloud Services Setup

ThingSpeak Configuration

Step 1: Create ThingSpeak Account

Step 2: Create Channel

Step 3: Get API Key

Adafruit IO Configuration

Step 1: Create Adafruit IO Account

Step 2: Create Feeds

Step 3: Get Credentials

Cloud Service Options

ThingSpeak Only

Adafruit IO Only

Both Services (Redundancy)

Offline Mode

Usage Guide

Offline Mode Operation

Initial Setup

Daily Operation

Maintenance

Online Mode Operation

Initial Setup

Web Interface Access

Remote Monitoring

Display Modes

LCD 1602 Operation

LCD 2004 Operation

Headless Mode Operation

Control Modes

Rotary Encoder Operation

Basic Configuration (`config.h`)