Circuit Documentation

Summary

This circuit is designed to monitor soil moisture levels and control a water pump accordingly. It uses an Arduino UNO as the central microcontroller to read data from a soil moisture sensor (YL-69 Sonda) through an LM393 comparator module (YL-83 Module LM393). The system drives a relay module (KY-019 Relay module 1 channel) to turn a water pump on or off based on the moisture level. Additionally, an I2C LCD screen (16x2) displays the status of the soil moisture and the state of the water pump. The circuit is powered by a 9V battery.

Component List

Arduino UNO

• Microcontroller board based on the ATmega328P
• Provides I/O pins and power for the circuit

KY-019 Relay module 1 channel

• A single-channel relay module for controlling high power devices
• Acts as a switch for the water pump

YL-69 Sonda

• A soil moisture sensor probe
• Detects the moisture level in the soil

YL-83 Module LM393

• A comparator module that interfaces with the YL-69 Sonda
• Outputs a digital signal representing the soil moisture level

I2C LCD 16x2 Screen

• An alphanumeric LCD display with I2C interface
• Displays the soil moisture status and water pump state

Water Pump

• A device that moves water through the system
• Controlled by the relay module

9V Battery

• Provides power to the circuit

Wiring Details

Arduino UNO

• GND connected to the ground of the circuit
• 5V provides power to other components
• A0 reads the analog output from the YL-83 Module LM393
• A4 (SDA) connected to the SDA pin of the I2C LCD Screen
• A5 (SCL) connected to the SCL pin of the I2C LCD Screen
• D7 controls the relay module

KY-019 Relay module 1 channel

• S signal pin connected to D7 on the Arduino UNO
• 5V and GND connected to the 5V and ground of the circuit
• COM connected to the positive terminal of the 9V Battery
• NO normally open contact connected to the positive terminal of the water pump

YL-69 Sonda

• + and - connected to the corresponding + and - pins on the YL-83 Module LM393

YL-83 Module LM393

• A0 connected to A0 on the Arduino UNO
• GND and VCC connected to the ground and 5V of the circuit
• + and - connected to the corresponding pins on the YL-69 Sonda

I2C LCD 16x2 Screen

• SDA connected to A4 (SDA) on the Arduino UNO
• SCL connected to A5 (SCL) on the Arduino UNO
• VCC (5V) and GND connected to the 5V and ground of the circuit

Water Pump

• positive terminal connected to the NO contact of the relay module
• negative terminal connected to the negative terminal of the 9V Battery

9V Battery

• + connected to the COM contact of the relay module
• - connected to the negative terminal of the water pump

Documented Code

#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27,16,2);

int sensor_pin = A0;
int relay_pin = 7;

void setup() {
  Serial.begin(9600);
  lcd.begin(16,2);
  lcd.backlight();
  lcd.setBacklight(HIGH);

  pinMode(sensor_pin,INPUT);
  pinMode(relay_pin,OUTPUT);

}

void loop() {
  int sensor_data = analogRead(sensor_pin);
  Serial.print("Sensor_data: ");
  Serial.print(sensor_data);
  Serial.print("\t | ");

  if(sensor_data > 950){
    Serial.print("No Moisture, Soil is Dry");
    digitalWrite(relay_pin, HIGH);

    lcd.setCursor(0,0);
    lcd.print("Soil is Dry");
    lcd.setCursor(0,1);
    lcd.print("Motor On");
  }
  else if(sensor_data >= 400 && sensor_data <=950){
    Serial.print("There is Some Moisture, Soil is Stable");
    digitalWrite(relay_pin, LOW);

    lcd.setCursor(0,0);
    lcd.print("Soil is Stable");
    lcd.setCursor(0,1);
    lcd.print("Motor Off");
  }
  else if(sensor_data < 400){
    Serial.print("Soil is Wet");
    digitalWrite(relay_pin, LOW);

    lcd.setCursor(0,0);
    lcd.print("Soil is Wet");
    lcd.setCursor(0,1);
    lcd.print("Motor Off");
  }

  delay(100);

}

This code is designed to run on the Arduino UNO. It initializes the LCD screen and sets up the sensor and relay pins. In the main loop, it reads the moisture level from the sensor and prints the value to the serial monitor. Depending on the moisture level, it controls the relay to turn the water pump on or off and updates the LCD display with the current soil status and pump state.