Circuit Documentation

Summary

The circuit in question is designed to monitor environmental conditions such as humidity and water level, and to control a DC motor based on these readings. The core of the circuit is an ESP32 microcontroller, which is responsible for reading sensor data, controlling the motor driver, and communicating with a server over WiFi. The circuit includes a humidity sensor (YL-69), two water level sensors, a 18650 Li-Ion battery for power, a motor driver to control the DC motor, and the DC motor itself.

Component List

Humidity Sensor (YL-69)

• Description: A sensor used to measure the humidity of the soil.
• Pins: A0 (Analog Output), D0 (Digital Output), GND (Ground), VCC (Power Supply).

18650 Li-Ion Battery

• Description: A rechargeable battery providing power to the circuit.
• Pins: Positive, Negative.

ESP32 Microcontroller

• Description: A powerful microcontroller with WiFi capabilities.
• Pins: EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, GND, VIN, 3V3, D15, D2, D4, RX2, TX2, D5, D18, D19, D21, RX0, TX0, D22, D23, BOOT.

Motor Driver

• Description: A module to control the DC motor.
• Pins: VB+ (Motor Power Supply Positive), VB- (Motor Power Supply Negative), M1A, M1B (Motor Control Pins), M2A, M2B (Unused Motor Control Pins), 5V (5V Output), GND (Ground).

DC Motor

• Description: A motor that converts electrical energy into mechanical motion.
• Pins: pin 1, pin 2.

Water Level Sensor

• Description: A sensor used to detect the level of water.
• Pins: SIG (Signal), VCC (Power Supply), GND (Ground).

Wiring Details

Humidity Sensor (YL-69)

• A0 connected to ESP32 VP
• D0 connected to ESP32 D2
• GND connected to common ground
• VCC connected to common 3V3

18650 Li-Ion Battery

• Positive connected to Motor Driver VB+ and ESP32 VIN
• Negative connected to common ground

ESP32 Microcontroller

• VP connected to Humidity Sensor A0
• VN connected to Water Level Sensor SIG
• D2 connected to Humidity Sensor D0
• D18 connected to Motor Driver M1A
• D19 connected to Motor Driver M1B
• GND connected to common ground
• VIN connected to 18650 Li-Ion Positive
• 3V3 connected to common 3V3

Motor Driver

• VB+ connected to 18650 Li-Ion Positive
• VB- connected to common ground
• M1A connected to ESP32 D18 and DC Motor pin 1
• M1B connected to ESP32 D19 and DC Motor pin 2
• 5V connected to common 3V3
• GND connected to common ground

DC Motor

• pin 1 connected to Motor Driver M1A
• pin 2 connected to Motor Driver M1B

Water Level Sensor

• SIG connected to ESP32 VN
• VCC connected to common 3V3
• GND connected to common ground

Documented Code

ESP32 Microcontroller Code

#include <WiFi.h>
#include <HTTPClient.h>
#include <L298N.h>

// Pin Definitions
const int humidityAnalogPin = VP; // A0 pin of Humidity YL-69
const int humidityDigitalPin = D2; // D0 pin of Humidity YL-69
const int waterLevelPin = VN; // SIG pin of Water Level Sensor

// Motor Pins
const int motorPin1 = D18; // IN1 pin of L298N
const int motorPin2 = D19; // IN2 pin of L298N
const int enablePin = D5;  // ENA pin of L298N

// WiFi Credentials
const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";

// Create L298N instance
L298N motor(motorPin1, motorPin2, enablePin);

void setup() {
  // Initialize Serial Monitor
  Serial.begin(115200);

  // Initialize Pins
  pinMode(humidityAnalogPin, INPUT);
  pinMode(humidityDigitalPin, INPUT);
  pinMode(waterLevelPin, INPUT);

  // Initialize Motor
  motor.setSpeed(0); // Set initial speed to 0

  // Connect to WiFi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
}

void loop() {
  // Read Humidity Sensor
  int humidityValue = analogRead(humidityAnalogPin);
  int humidityDigitalValue = digitalRead(humidityDigitalPin);
  Serial.print("Humidity Analog Value: ");
  Serial.println(humidityValue);
  Serial.print("Humidity Digital Value: ");
  Serial.println(humidityDigitalValue);

  // Read Water Level Sensor
  int waterLevelValue = analogRead(waterLevelPin);
  Serial.print("Water Level Value: ");
  Serial.println(waterLevelValue);

  // Control Motor Based on Sensor Readings
  if (humidityDigitalValue == LOW || waterLevelValue < 500) {
    // Turn on Motor
    motor.setSpeed(255); // Set speed to maximum
    motor.forward();     // Move motor forward
  } else {
    // Turn off Motor
    motor.setSpeed(0);   // Stop motor
  }

  // Send Data to Server
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    http.begin("http://yourserver.com/api/data");
    http.addHeader("Content-Type", "application/json");

    String jsonData = "{\"humidityAnalog\":" + String(humidityValue) + 
                      ",\"humidityDigital\":" + String(humidityDigitalValue) + 
                      ",\"waterLevel\":" + String(waterLevelValue) + "}";

    int httpResponseCode = http.POST(jsonData);
    if (httpResponseCode > 0) {
      String response = http.getString();
      Serial.println(httpResponseCode);
      Serial.println(response);
    } else {
      Serial.print("Error on sending POST: ");
      Serial.println(httpResponseCode);
    }
    http.end();
  }

  // Delay for Stability
  delay(1000);
}

This code is responsible for initializing the ESP32 microcontroller and its connected components, reading sensor data, controlling the motor based on the sensor data, and sending the sensor data to a server over WiFi.