Circuit Documentation

Summary

This circuit is designed to control a DC motor and a 12V blue LED via an Arduino Nano, which is interfaced with an HC-05 Bluetooth module for wireless communication. The circuit also includes a 4-channel 5V relay module to switch the DC motor and LED on and off, a 16x2 I2C LCD for display purposes, and a 5V 5A power supply to power the components. Additionally, a 9V battery and a Li-ion 5000mAh battery are included to provide power to the motor and LED, respectively. The power supply is connected to a power outlet for AC input.

Component List

Arduino Nano

A compact microcontroller board based on the ATmega328P, featuring digital and analog I/O pins.

DC Motor

An electric motor that runs on direct current (DC) electricity.

12V Blue LED

A blue light-emitting diode that operates at 12 volts.

Relay 4 Channel 5V

A 4-channel relay module that allows for controlling high power devices with low power signals.

HC-05 Bluetooth Module

A Bluetooth module that enables wireless communication with the Arduino.

16x2 I2C LCD

A liquid crystal display with 16 characters by 2 lines, interfaced via the I2C protocol.

POWER SUPPLY 5V 5AMP

A power supply unit that converts 220V AC to 5V DC with a 5A current rating.

9V Battery

A standard 9V battery used to provide power to the circuit.

Li-ion 5000mAh Battery

A rechargeable lithium-ion battery with a capacity of 5000mAh and a nominal voltage of 11.1V.

Power Outlet (IL)

A power outlet interface for connecting the power supply to the AC mains.

Wiring Details

Arduino Nano

• D0/RX connected to HC-05 Bluetooth Module TXD
• D1/TX connected to HC-05 Bluetooth Module RXD
• GND connected to common ground
• 5V and VIN connected to 5V power rail
• A4 connected to 16x2 I2C LCD SDA
• A5 connected to 16x2 I2C LCD SCL
• D4 connected to Relay 4 Channel 5V IN3
• D5 connected to Relay 4 Channel 5V IN4

DC Motor

• pin 1 connected to 9V battery -
• pin 2 connected to Relay 4 Channel 5V NO3

12V Blue LED

• GND connected to Li-ion 5000mAh Battery GND
• VCC connected to Relay 4 Channel 5V NO4

Relay 4 Channel 5V

• GND connected to common ground
• VCC connected to 5V power rail
• IN3 and IN4 controlled by Arduino Nano
• COM3 connected to 9V battery +
• COM4 connected to Li-ion 5000mAh Battery 11.1V
• NO3 connected to DC Motor pin 2
• NO4 connected to 12V Blue LED VCC

HC-05 Bluetooth Module

• RXD connected to Arduino Nano D1/TX
• TXD connected to Arduino Nano D0/RX
• GND connected to common ground
• VCC connected to 5V power rail

16x2 I2C LCD

• GND connected to common ground
• VCC connected to 5V power rail
• SDA connected to Arduino Nano A4
• SCL connected to Arduino Nano A5

POWER SUPPLY 5V 5AMP

• 220V Positive Pole (AC) connected to power outlet L
• 220V Negative Pole (AC) connected to power outlet N
• GND (DC) connected to common ground
• 12V-24V Output (DC) connected to 5V power rail

9V Battery

• + connected to Relay 4 Channel 5V COM3
• - connected to DC Motor pin 1

Li-ion 5000mAh Battery

• 11.1V connected to Relay 4 Channel 5V COM4
• GND connected to 12V Blue LED GND

Power Outlet (IL)

• N connected to POWER SUPPLY 5V 5AMP 220V Negative Pole (AC)
• L connected to POWER SUPPLY 5V 5AMP 220V Positive Pole (AC)
• GND connected to POWER SUPPLY 5V 5AMP GND

Documented Code

#include<EEPROM.h>
#include<SoftwareSerial.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2); // Adjust address if necessary

// Define relay pins
const int relayMotor = 4; // Relay channel for DC motor
const int relayLED = 5;   // Relay channel for LED module

// Define HC-05 Bluetooth Serial
#define BTSerial Serial

void setup() {
  // Set up relay pins
  pinMode(relayMotor, OUTPUT);
  pinMode(relayLED, OUTPUT);

  // Initially turn off all relays
  digitalWrite(relayMotor, HIGH); // Relay modules are typically active LOW
  digitalWrite(relayLED, HIGH);

  // Initialize LCD
  lcd.begin();
  lcd.backlight(); // Turn on the LCD backlight
  lcd.clear();
  lcd.print("Ready for Commands");

  // Initialize Serial for HC-05 Bluetooth
  BTSerial.begin(9600);  // Default baud rate for HC-05
}

void loop() {
  // Check if data is available from Bluetooth
  if (BTSerial.available()) {
    char command = BTSerial.read();

    // Process received command
    switch (command) {
      case '1': // Turn on LCD display
        lcd.display();
        lcd.backlight();
        lcd.clear();
        lcd.print("LCD is ON");
        break;

      case '2': // Turn off LCD display
        lcd.noDisplay();
        lcd.noBacklight();
        lcd.clear();
        break;

      case '3': // Turn on Motor
        digitalWrite(relayMotor, LOW); // Relay active LOW
        lcd.clear();
        lcd.print("Motor is ON");
        break;

      case '4': // Turn off Motor
        digitalWrite(relayMotor, HIGH); // Relay off
        lcd.clear();
        lcd.print("Motor is OFF");
        break;

      case '5': // Turn on LED
        digitalWrite(relayLED, LOW); // Relay active LOW
        lcd.clear();
        lcd.print("LED is ON");
        break;

      case '6': // Turn off LED
        digitalWrite(relayLED, HIGH); // Relay off
        lcd.clear();
        lcd.print("LED is OFF");
        break;

      default:
        lcd.clear();
        lcd.print("Unknown Command");
        break;
    }
    delay(1000); // Small delay for readability
  }
}

This code is designed to run on the Arduino Nano and controls the relay module to switch the DC motor and LED on and off based on commands received via Bluetooth. It also updates the LCD display with the status of the devices.