Bluetooth based home automation

Bluetooth based home automation, project allows you to control electrical appliances using your android mobile phone. It consists of ATmega8 microcontroller, HC-06 Bluetooth module, Relays.

There are many Home Automation Systems available in our market. Most of these are simple home appliances controlling systems like DTMF controlled home Appliances, IR Remote based home appliances controlling, RF based home appliances controlling. we are going to discuss about Bluetooth based Home/Office Appliances Control (Home Automation System).

Here all circuit details with PCB design, Code and Android application are provided.

Features:
1. Control your home electrical appliances using smart android phone.
2. Simple easy to use Android App to control your devices.
3. Uses Standard Bluetooth Module HC-06. 
4. Digital Switches are provided for manual operation.
5. Low Cost.

Step 1: Components Required
1. Atmega 8 Microcontroller
2. Relays

3. ULN2003
4. LM7805
5. BC548
6. 1K Ohm Resistors
7. Bluetooth Module

8. Buzzer

Step 2: Circuit Design and PCB Manufacturing

Step 3: Programming the controller

AVR Studio C Code

/*********************************************************************************/
/*       Bluetooth based home automation                      */
/*   www.circuits4you.com               */
/*   blog.circuits4you.com               */
/*********************************************************************************/
#include <avr/io.h>
#include <string.h>
#include <avr/interrupt.h>
//Relay Connection
#define D0   PC1
#define D1   PC2
#define D2   PC3
#define D3   PC4

//Switches Connection
#define S1  PB1
#define S2  PB0

#define S3  PB2
#define S4  PD7

#define S5  PB3
#define S6  PD6

#define S7  PB4
#define S8  PD5

//Declaration
unsigned char u8_data;
void delay(unsigned int de);
void USART_Init();
void Process();

/*********************************************************************************/
/*         Main Routine                                 */
/*********************************************************************************/
int main(void)
{
 delay(100);
 DDRB = 0b00011111; 
 PORTB = 0b00011111; //Enable internal pullups for switches
 DDRD = 0b11100010;  //Enable internal pullups for switches
 PORTD = 0b11100000;
 DDRC = 0b00011110; //Relay port directions 

 //Enable Interrupt
 USART_Init();
 SREG=0x80;
 delay(100);

 while(1)
 {
  Process();
 }

}

/*********************************************************************************/
/*         Delay of 1mSec                               */
/*********************************************************************************/
void delay(unsigned int de)
{
unsigned int rr,rr1;
   for (rr=0;rr<de;rr++)
   {
   
  for(rr1=0;rr1<30;rr1++)   //395
  {
   asm("nop");
  }
   
   }
}

/*********************************************************************************/
/*         RS232 Intitialize                            */
/*********************************************************************************/
void USART_Init()
{
/* Set baud rate */
 UBRRH = 0x00;  //9600 @ 8MHz
 UBRRL =103; 
//Set double speed
  UCSRA |= (1<<U2X);
/* Enable receiver and transmitter */
 UCSRB = (1<<RXEN)|(1<<TXEN);
/* Set frame format: 8data, 2stop bit */
// UCSRC = (1<<URSEL)|(1<<USBS)|(3<<UCSZ0);
//Set interrupt on RX
  UCSRB |= (1<<RXCIE);
}

/*********************************************************************************/
/*         RS232 Interrupt                              */
/*********************************************************************************/
SIGNAL(USART_RXC_vect)
{
 u8_data=UDR;
 switch(u8_data){
 case 0x03:
  PORTC |= (1<<D0);  //Relay 1 On
 break;
 case 0x04:
  PORTC &= ~(1<<D0);  //Relay 1 Off
 break;
 case 0x05:
  PORTC |= (1<<D1);  //Relay 2 On
 break;
 case 0x06:
  PORTC &= (1<<D1);  //Relay 2 Off
 break;      
 case 0x07:
  PORTC |= (1<<D2);  //Relay 3 On
 break;
 case 0x08:
  PORTC &= (1<<D2);  //Relay 3 Off
 break;      
 case 0x09:
  PORTC |= (1<<D3);  //Relay 4 On
 break;
 case 0x0A:
  PORTC &= (1<<D3);  //Relay 4 Off
 break;      
 case 0x0B:  //All on
  PORTC |= (1<<D0);
  PORTC |= (1<<D1);
  PORTC |= (1<<D2);
  PORTC |= (1<<D3);
 break;

 case 0x0C:  //All off
  PORTC &=~(1<<D0);
  PORTC &=~(1<<D1);
  PORTC &=~(1<<D2);
  PORTC &=~(1<<D3);
 break;
   }
 return; 
}


/*********************************************************************************/
/*         Process                                      */
/*********************************************************************************/
void Process()
{
  delay(100);
//Switch 1============================================
   if((PINB & 0x02) == 0x02)
   {
    PORTC |= (1<<D0);
   }
   if((PINB & 0x01) == 0x01)
   {
    PORTC &=~ (1<<D0);
   }
   delay(10);
//Switch 2============================================
   if((PINB & 0x04) == 0x04)
   {
    PORTC |= (1<<D1);
   }
   if((PIND & 0x80) == 0x80)
   {
    PORTC &=~ (1<<D1);
   }   
   delay(10);  
//Switch 3============================================
   if((PINB & 0x08) == 0x08)
   {
    PORTC |= (1<<D2);
   }
   if((PIND & 0x40) == 0x40)
   {
    PORTC &=~ (1<<D2);    
   }
   delay(10);
//Switch 4============================================ 
   if((PINB & 0x10) == 0x10)
   {
    PORTC |= (1<<D3);
   }
   if((PIND & 0x20) == 0x20)
   {
    PORTC &=~ (1<<D3);
   }
   delay(10);

}

/*********************************************************************************/
/*         END                                          */
/*********************************************************************************/

Step 4: Download Android App

Step 5: Test the code and Hardware
1. Install Android app on your phone.
2. Allow third party download
3. Pair HC-06
4. Then start the software 
5. Follow us on Google+
6. You Did it Yourself
7. Refer Tutorials from this site for more understanding of code and Circuits