Circuit Documentation

Summary

This document provides a detailed overview of a circuit that integrates various sensors, actuators, and a microcontroller (ESP32-S3) to monitor environmental conditions and control devices such as a water pump, fan, and buzzer. The circuit includes components like a power supply, step-down regulator, relays, sensors (DHT22, MQ135, LDR, HC-SR04), and actuators (water pump, fan, buzzer, LED). The ESP32-S3 microcontroller is programmed to read sensor data and control the actuators based on predefined conditions.

Component List

1. ESP32-S3

   • Description: A powerful microcontroller with Wi-Fi and Bluetooth capabilities.
   • Pins: 3v3, EN, GPIO4, GPIO5, GPIO6, GPIO7, GPIO15, GPIO16, GPIO17, GPIO18, GPIO8, GPIO46, GPIO9, GPIO10, GPIO11, GPIO12, GPIO13, GPIO14, 5V, GND, GPIO43, GPIO44, GPIO1, GPIO2, GPIO42, GPIO41, GPIO40, GPIO39, GPIO38, GPIO37, GPIO36, GPIO35, GPIO0, GPIO45, GPIO48, GPIO47, GPIO21, GPIO20, GPIO19

2. POWER SUPPLY 12V 5AMP

   • Description: Provides 12V DC power from a 220V AC source.
   • Pins: 220V Positive Pole (AC), 220V Negative Pole (AC), GND, GND (DC), 12V-24V Output (DC)

3. Regulator Stepdown DC with LCD Display

   • Description: Steps down the voltage from 12V to 5V.
   • Pins: IN +, IN -, OUT +, OUT -

4. 1-Channel Relay (5V 10A)

   • Description: Controls high-power devices using a low-power signal.
   • Pins: NC, signal, C, power, NO, ground

5. 5v mini water pump

   • Description: A small water pump operating at 5V.
   • Pins: positive pin, negative pin

6. power 220v

   • Description: Provides 220V AC power.
   • Pins: hot wire, neutral wire

7. Buzzer Module

   • Description: Emits sound when activated.
   • Pins: GND, Vcc, I/O

8. DHT22

   • Description: Temperature and humidity sensor.
   • Pins: +, Out, -

9. MQ135

   • Description: Air quality sensor.
   • Pins: VCC, GND, A0, D0

10. LDR

    • Description: Light-dependent resistor for measuring light intensity.
    • Pins: A0, D0, GND, VCC

11. HC-SR04 Ultrasonic Sensor

    • Description: Measures distance using ultrasonic waves.
    • Pins: VCC, TRIG, ECHO, GND

12. Fan

    • Description: A small fan operating at 5V.
    • Pins: GND, 5V

13. Resistor

    • Description: 220 Ohms resistor.
    • Pins: pin1, pin2

14. LED: Two Pin (yellow)

    • Description: A yellow LED.
    • Pins: cathode, anode

15. Water Level Sensor

    • Description: Measures water level.
    • Pins: SIG, VCC, GND

Wiring Details

ESP32-S3

• GPIO6 connected to HC-SR04 Ultrasonic Sensor TRIG
• GPIO7 connected to 1-Channel Relay (5V 10A) signal
• GPIO15 connected to DHT22 Out
• GPIO16 connected to Resistor pin2
• GPIO17 connected to LDR A0
• GPIO18 connected to HC-SR04 Ultrasonic Sensor ECHO
• GPIO8 connected to Water Level Sensor SIG
• GPIO12 connected to Buzzer Module I/O
• GPIO14 connected to 1-Channel Relay (5V 10A) signal
• GPIO35 connected to MQ135 A0

POWER SUPPLY 12V 5AMP

• 220V Positive Pole (AC) connected to power 220v hot wire
• 220V Negative Pole (AC) connected to power 220v neutral wire
• GND (DC) connected to Regulator Stepdown DC with LCD Display IN -
• 12V-24V Output (DC) connected to Regulator Stepdown DC with LCD Display IN +

Regulator Stepdown DC with LCD Display

• OUT + connected to:
  • 1-Channel Relay (5V 10A) power
  • Water Level Sensor VCC
  • Buzzer Module Vcc
  • DHT22 +
  • LDR VCC
  • MQ135 VCC
  • HC-SR04 Ultrasonic Sensor VCC
  • 1-Channel Relay (5V 10A) power
  • Fan 5V
  • 1-Channel Relay (5V 10A) NO
• OUT - connected to:
  • Water Level Sensor GND
  • Buzzer Module GND
  • 1-Channel Relay (5V 10A) ground
  • 5v mini water pump negative pin
  • 1-Channel Relay (5V 10A) C
  • LED: Two Pin (yellow) cathode
  • DHT22 -
  • LDR GND
  • MQ135 GND
  • HC-SR04 Ultrasonic Sensor GND
  • 1-Channel Relay (5V 10A) ground
  • 1-Channel Relay (5V 10A) C
  • Fan GND

1-Channel Relay (5V 10A)

• NO connected to 5v mini water pump positive pin

Resistor

• pin1 connected to LED: Two Pin (yellow) anode

Documented Code

ESP32-S3 Code

#include <DHT.h>

#define DHTPIN 15 // GPIO15 for DHT22
#define DHTTYPE DHT22

const int ldrPin = 36; // GPIO36 for LDR sensor
const int soilMoisturePin = 39; // GPIO39 for Soil Moisture sensor
const int mq135Pin = 35; // GPIO35 for MQ135 sensor
const int trigPin = 6; // GPIO6 for HC-SR04 TRIG
const int echoPin = 18; // GPIO18 for HC-SR04 ECHO
const int buzzerPin = 12; // GPIO12 for Buzzer
const int ledPin = 16; // GPIO16 for LED
const int relayWaterPumpPin = 7; // GPIO7 for Relay controlling water pump
const int relayFanPin = 14; // GPIO14 for Relay controlling fan

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);
  pinMode(ldrPin, INPUT);
  pinMode(soilMoisturePin, INPUT);
  pinMode(mq135Pin, INPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(relayWaterPumpPin, OUTPUT);
  pinMode(relayFanPin, OUTPUT);

  dht.begin();
}

void loop() {
  // Read LDR value
  int ldrValue = analogRead(ldrPin);
  Serial.print("LDR Value: ");
  Serial.println(ldrValue);

  // Read Soil Moisture value
  int soilMoistureValue = analogRead(soilMoisturePin);
  Serial.print("Soil Moisture Value: ");
  Serial.println(soilMoistureValue);

  // Read DHT22 values
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.print("%  Temperature: ");
  Serial.print(temperature);
  Serial.println("°C");

  // Read MQ135 value
  int mq135Value = analogRead(mq135Pin);
  Serial.print("MQ135 Value: ");
  Serial.println(mq135Value);

  // Read HC-SR04 value
  long duration, distance;
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration / 2) / 29.1;
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Control LED based on LDR value
  if (