home automation system using gsm

WIRELESS HOME AUTOMATION SYSTEM USING GSM

Dept. Of Telecommunication, SIT Tumkur

MINI PROJECT REPORT

ON

“WIRELESS HOME AUTOMATION SYSTEM USING GSM”

Work carried out at

SIDDAGANGA INSTITUTE OF TECHNOLOGY, TUMKUR

Submitted in partial fulfilment of the requirement for the award of

Bachelor of Engineering

Of

Visvesvaraya Technology University, Belgaum

By

MONICA SINGH 1SI11TE030

HARSHA JAISWAL 1SI11TE017

ROHIT SINHA 1SI11TE038

Under the guidance of

Mrs.D.K.KUMUDA

Associate professor

Department of TE

SIT, Tumkur.



SIDDAGANGA INSTITUTE OF TECHNOLOGY, TUMKUR-572103

(An Autonomous Institute under Visvesvaraya Technological University, Belgaum)

DEPARTMENT OF TELECOMMUNICATION ENGINEERING

CERTIFICATE

Certified that the project work entitled “WIRELESS HOME AUTOMATION SYSTEM

USING GSM” is a bonafied work carried out by Monica Singh (1SI11TE030), Rohit

Sinha (1SI11TE038), Harsha Jaiswal (1SI11TE017) in partial fulfilment of the

requirement for the award of the degree in BE, Telecommunication Engineering,

Visvesvaraya Technological University, Belgaum during the year 2013-14.It is certified

that all corrections / suggestion indicated for Internal Assessment have been

incorporated in the Report. The project report has been approved as it satisfies the

academic requirements in respect of project work prescribed for the Bachelor of

Engineering Degree.

GUIDE H.O.D PRINCIPAL

D.K KUMUDA Dr.K.C.Narsimhamurthy Dr.Shivakumaraiah

Associate Professor Professor & Head Principle

Department of TE Department of TE S.I.T, TUMKUR

S.I.T, Tumkur S.I.T, Tumkur

Submitted by : Harsha Jaiswal (1SI11TE017)

Monica Singh (1SI11TE030)

Rohit Sinha(1SI11TE038)



ACKNOWLEDGEMENT

We are highly indebted to our Faculty Mrs.D.K.KUMUDA,

Telecommunication Engineering Department, who has given us all the

necessary technical guidance in carrying out this Project.

We wish to express our sincere thanks to Dr K.C.NARSIMHAMURTHY, Head

of the Department of Telecommunication Engineering, S.I.T, for permitting us

to pursue our Project and encouraging us throughout the Project.

Finally, we thank all the people who have directly or indirectly help us through

the course of our Project.

We express our deep sense of gratitude to Dr.Madhusudhan , Tumkur, for his

valuable guidance and encouragement in carrying out our Project.



ABSTRACT

Now a day's every system is automated in order to face new

challenges in the present day situation. Automated systems have less

manual operations, so that the flexibility, reliabilities are high and

accurate. Hence every field prefers automated control systems.

Especially in the field of electronics automated systems are doing

better performance.

Probably the most useful thing to know about the global system for

mobile communication is that it is an international standard. If you

travel in parts of world, GSM is only type of cellular service

available. Instead of analog services, GSM was developed

as a digital system using TDMA technology.

The goal of the project is to develop a system, which uses Mobile

technology that keeps control of the various units of the home

appliances, which executes with respect to the signal sent by the

mobile.

For utilization of appliances the new concept has been thought to

manage them remotely by using GSM, which enables the user to

remotely control switching of domestic appliances. Just by dialing

keypad of remote telephone, from where we are calling we can

perform ON / OFF operation of the appliances.

The ranges of appliances that can be controlled through tele remote

systems are many in numbers. Some of them are as follows and this

depends upon the usage priority of the appliances i.e. Lights, Music

System or other electrical / electronic appliances.



CONTENTS

ACKNOWLEDGEMENTS

ABSTRACT

LIST OF FIGURES LIST OF TABLES

CHAPTER 1. INTRODUCTION 1.1 Aim of the project

1.2 Significance and applications

CHAPTER 2. OVERVIEW 2.1 Overview of project

2.1.1 Block Diagram

2.1.2 Circuit Diagram

2.1.3 Description

CHAPTER3. HARDWARE DESCRIPTION 3.1 Microcontroller

3.1.1 A Brief History of 8051

3.1.2 Description of 89S52 Microcontroller

3.1.3 Pin Configurations

3.1.4 Relay

CHAPTER 4. POWER SUPPLY 4.1 Transformer

4.2 Rectifier

4.3 Voltage Regulator

CHAPTER 5.LIQUID CRYSTAL DISPLAY 5.1 LCD Screen

CHAPTER 6.RS-232 AND MAX 232

CHAPTER 7.GSM MODEM

CHAPTER 8.SOFTWARE IMPLEMENTATION

CHAPTER 9.CONCLUSION

REFERENCE



CHAPTER 1

1. INTRODUCTION

1. Introduction

1.1 Aim of the project: The aim of the project is to develop a system, which uses Mobile technology

that keeps control of the various units of the automobiles, Computer system,

which executes with respect to the signal sent by the mobile.

1.2 Significance and applications: GSM BASED HOME AUTOMATION plays a very important role in

domestic applications. The ease of operation of the kit and low cost add up as an

additional advantage for its usage. Its significance can be proved by considering

the following specialties of kit designed by us.

Reliability: Reliability is one such factor that every electrical system

should have in order to render its services without malfunctioning over along

period of time. We have designed our kit using AT89S52 micro controller

which is itself very reliable and also operates very efficiently under normal

condition.

Cost: The design is implemented at a very economical price. The total

cost incurred by us in designing this kit is very less and further we have

developed the GSM based Home Automation which is more economical rather

than just interfacing those which are readily available in the market.

For utilization of appliances the new concept has been thought to

manage them remotely by using GSM, which enables the user to remotely

control switching of domestic appliances.

The ranges of appliances that can be controlled through cell phones

are many in numbers. Some of them are as follows and this depends upon the

usage priority of the appliances i.e. Lights, Fans or other electrical / electronic

appliances.



CHAPTER 2

2. OVERVIEW

2.1Overview of Project

2.1.1 Block Diagram

2.1.2 Circuit Diagram



2.1.3 Description

In this project we are going to control general home appliances based

on the mobile communication. The idea behind this particular work is to give

user the full flexibility to control the appliances from remote distances when

there is a busy schedule concerned to his daily routine.

The main parts of this schematic diagram are:

1. POWER SUPPLY.

2. (AT89C52) MICROCONTROLLER UNIT.

3. RS 232 CABLE

4. RELAYS

5. GSM MODEM

6. BULB

7. BUZZER

8. FAN

The process to operate this project is first make a mobile to mobile

connection wirelessly or with a single mobile onboard wired. But here we are

using to mobiles to make is a wireless application. Start with making a

connection with the onboard mobile from remote distance, then when

connection is established lets control the project with the data as follows:

To operate the BULB just press “1” to switch ON and also to switch OFF

again press “0”. This ON/OFF condition of BULB is through Relay where

switching is very fast and accurate.

To operate the BUZZER just press “2” to switch ON and also to switch

OFF again press “0”. This ON/OFF condition of PLUG is through Relay where

switching is very fast and accurate

To operate the FAN just press “4” to switch ON and also to switch OFF

again press “0”. This ON/OFF condition of DC MOTOR is through Relay

where switching is very fast and accurate.



CHAPTER 3

3. HARDWARE DESCRIPTION

The block diagram of the system is as shown in the fig. The system basically

consists of a

1. Micro controller

2. GSM module

3. LED

4. Relay

5. Power supply

3.1 Microcontroller Architecture 3.1.1 A Brief History of 8051 In 1981, Intel Corporation introduced an 8 bit microcontroller called

8051. This microcontroller had 128 bytes of RAM, 4K bytes of chip ROM, two

timers, one serial port, and four ports all on a single chip. At the time it was also

referred as “A SYSTEM ON A CHIP” The 8051 is an 8-bit processor meaning that the CPU can work only on 8

bits data at a time. Data larger than 8 bits has to be broken into 8 bits pieces to

be processed by the CPU. The 8051 has a total of four I\O ports each 8 bit wide.

There are many versions of 8051 with different speeds and amount of on-

chip ROM and they are all compatible with the original 8051. This means that if

you write a program for one it will run on any of them.

The 8052 is an original member of the 8051 family. There are two other

members in the 8051 family of microcontrollers. They are 8052 and 8031. All

the three microcontrollers will have the same internal architecture, but they

differ in the following aspects.

1. 8031 has 128 bytes of RAM, two timers and 6 interrupts.

2. 89S51 has 4KB ROM, 128 bytes of RAM, two timers and 6 interrupts

3. 89S52 has 8KB ROM, 128 bytes of RAM, three timers and 8 interrupts.

Of the three microcontrollers, 89S51 is the most preferable. Microcontroller

supports both serial and parallel communication.

In the concerned project 89S52 microcontroller is used. Here microcontroller

used is AT89S52, which is manufactured by ATMEL laboratories.



3.1.2 Description of 89S52 Microcontroller The AT89S52 provides the following standard features: 8Kbytes of Flash,

256bytes of RAM, 32 I/O lines, three 16-bit timer/counters, six-vector two-level

interrupt architecture, a full duplex serial port, on-chip oscillator, and clock

circuitry. In addition, the AT89S52 is designed with static logic for operation

down to zero frequency and supports two software selectable power saving

modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters,

serial port, and interrupt system to continue functioning. The Power down Mode

saves the RAM contents but freezes the oscillator, disabling all other chip

functions until the next hardware reset.

By combining a versatile 8-bit CPU with Flash on a monolithic chip, the

AT89S52 is a powerful microcomputer which provides a highly flexible and

cost effective solution to many embedded control applications.

Features of Microcontroller (89S52)

1. Compatible with MCS-51 Products

2. 8 Kbytes of In-System Reprogrammable Flash Memory

3. Endurance: 1,000 Write/Erase Cycles

4. Fully Static Operation: 0 Hz to 24 MHz

5. Three-Level Program Memory Lock

6. 256 x 8-Bit Internal RAM

7. 32 Programmable I/O Lines

8. Three 16-Bit Timer/Counter

9. Eight vector two level Interrupt Sources

10. Programmable Serial Channel



3.1.3 Pin Configurations

Figure 3.2 Pin Diagram of 89S52

Pin Description

VCC Pin 40 provides Supply voltage to the chip. The voltage source is +5v

GND

Pin 20 is the grounded

Port 0 Port 0 is an 8-bit open drain bidirectional I/O port from pin 32 to 39. As an

output port each pin can sink eight TTL inputs. When 1s are written to port 0

pins, the pins can be used as high-impedance inputs. Port 0 may also be



configured to be the multiplexed low-order address/data bus during accesses to

external program and data memory. In this mode P0 has internal pull-ups.

Port 1 Port 1 is an 8-bit bidirectional I/O port with internal pull-ups from pin 1 to 8.

The Port 1 output buffers can sink/source four TTL inputs. When 1s are written

to Port 1 pins they are pulled high by the internal pull-ups and can be used as

inputs. As inputs, Port 1 pins that are externally being pulled low will source

current (IIL) because of the internal pull-ups.

In addition, P1.0 and P1.1 can be configured to be the timer/counter 2 external

count input (P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX),

respectively, as shown in following table.


The Port 2 output buffers can sink / source four TTL inputs. When 1s are

written to Port 2 pins they are pulled high by the internal pull-ups and can be

used as inputs. As inputs, Port 2 pins that are externally being pulled low will

source current (IIL) because of the internal pull-ups.

Port 2 emits the high-order address byte during fetches from external program

memory and during accesses to external data memory that uses 16-bit addresses

(MOVX @ DPTR). In this application it uses strong internal pull-ups when

emitting 1s. During accesses to external data memory that uses 8-bit addresses

(MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register.

Port 2 also receives the high-order address bits and some control signals during

Flash programming and verification.


The Port 3 output buffers can sink / source four TTL inputs. When 1s are

written to Port 3 pins they are pulled high by the internal pull-ups and can be



used as inputs. As inputs, Port 3 pins that are externally being pulled low will

source current (IIL) because of the pull-ups.

Port 3 also serves the functions of various special features of the AT89C52 as

listed below:

Table 3.1 Special Features of port3

RST Pin 9 is the Reset input. It is active high. Upon applying a high pulse to this pin,

the microcontroller will reset and terminate all activities. A high on this pin for

two machine cycles while the oscillator is running resets the device.

ALE/PROG Address Latch is an output pin and is active high. Address Latch Enable output

pulse for latching the low byte of the address during accesses to external

memory. This pin is also the program pulse input (PROG) during Flash

programming. In normal operation ALE is emitted at a constant rate of 1/6 the

oscillator frequency, and may be used for external timing or clocking purposes.

PSEN Program Store Enable is the read strobe to external program memory. When the

AT89S52 is executing code from external program memory, PSEN is activated

twice each machine cycle, except that two PSEN activations are skipped during

each access to external data memory.

EA/VPP External Access Enable EA must be strapped to GND in order to enable the

device to fetch code from external program memory locations starting at 0000H

up to FFFFH. Note, however, that if lock bit 1 is programmed, EA will be



internally latched on reset. EA should be strapped to VCC for internal program

executions. This pin also receives the 12-volt programming enable voltage

(VPP) during Flash programming when 12-volt programming is selected.

XTAL1 Input to the inverting oscillator amplifier and input to the internal clock

operating circuit.

XTAL2 Output from the inverting oscillator amplifier.

3.1.5 RELAYS A relay is an electrically operated switch. Current flowing through the coil of

the relay creates a magnetic field which attracts a lever and changes the switch

contacts.The coil current can be on or off so relays have two switch positions

and they are double throw (changeover) switches.

Relays allow one circuit to switch a second circuit which can be

completely separate from the first. For example a low voltage battery circuit can

use a relay to switch a 230V AC mains circuit. There is no electrical connection

inside the relay between the two circuits; the link is magnetic and mechanical.

The coil of a relay passes a relatively large current, typically 30mA for a

12V relay, but it can be as much as 100mA for relays designed to operate from

lower voltages. Most ICs (chips) cannot provide this current and a transistor is

usually used to amplify the small IC current to the larger value required for the

relay coil. The maximum output current for the popular 555 timer IC is 200mA

so these devices can supply relay coils directly without amplification.



Most relays are designed for PCB mounting but you can solder wires

directly to the pins providing you take care to avoid melting the plastic case of

the relay. The supplier's catalogue should show you the relay's connections. The

coil will be obvious and it may be connected either way round. Relay coils

produce brief high voltage 'spikes' when they are switched off and this can

destroy transistors and ICs in the circuit. To prevent damage you must connect a

protection diode across the relay coil.

The relay's switch connections are usually labelled COM, NC and NO:

· COM = Common, always connect to this, it is the moving part of the switch.

· NC = Normally Closed, COM is connected to this when the relay coil is off.

· NO = Normally Open, COM is connected to this when the relay coil is on.

· Connect to COM and NO if you want the switched circuit to be on when the

Relay coil is on.

· Connect to COM and NC if you want the switched circuit to be on when the

Relay coil is off.

Advantages of relays: · Relays can switch AC and DC, transistors can only switch DC.

· Relays can switch high voltages, transistors cannot.

· Relays are a better choice for switching large currents (> 5A).

· Relays can switch many contacts at once.

Disadvantages of relays:

· Relays are bulkier than transistors for switching small currents.

· Relays cannot switch rapidly (except reed relays), transistors can switch

many times per second.

· Relays use more power due to the current flowing through their coil.



CHAPTER 4

POWER SUPPLY

All digital circuits require regulated power supply. In this article we are going to

learn how to get a regulated positive supply from the mains supply.

Figure shows the basic block diagram of a fixed regulated power supply. Let us

go through each block.

4.1 TRANSFORMER

A transformer consists of two coils also called as “WINDINGS” namely

PRIMARY & SECONDARY. They are linked together through inductively

coupled electrical conductors also called as CORE. A changing current in the

primary causes a change in the Magnetic Field in the core & this in turn induces

an alternating voltage in the secondary coil. If load is applied to the secondary

then an alternating current will flow through the load. If we consider an ideal

condition then all the energy from the primary circuit will be transferred to the

secondary circuit through the magnetic field.

So



The secondary voltage of the transformer depends on the number of turns in the Primary

as well as in the secondary.

4.2 RECTIFIER

A rectifier is a device that converts an AC signal into DC signal. For

rectification purpose we use a diode, a diode is a device that allows current to

pass only in one direction i.e. when the anode of the diode is positive with

respect to the cathode also called as forward biased condition & blocks current

in the reversed biased condition.

Bridge Rectifier.

As the name suggests it converts the full wave i.e. both the positive & the

negative half cycle into DC thus it is much more efficient than Half Wave

Rectifier & that too without using a center tapped transformer thus much more

cost effective than Full Wave Rectifier. Full Bridge Wave Rectifier consists of

four diodes namely D1, D2, D3 and D4. During the positive half cycle diodes

D1 & D4 conduct whereas in the negative half cycle diodes D2 & D3 conduct

thus the diodes keep switching the transformer connections so we get positive

half cycles in the output.



If we use a center tapped transformer for a bridge rectifier we can get both

positive & negative half cycles which can thus be used for generating fixed

positive & fixed negative voltages.

4.3 VOLTAGE REGULATOR

A Voltage regulator is a device which converts varying input voltage into a

constant regulated output voltage. The IC 7805 is used which is a three terminal

voltage regulator, to get the constant output voltage of 5V.

3 Circuit diagram:

Fig 2.3. Circuit Diagram of power supply

IC 7805:

7805 is an integrated three-terminal positive fixed linear voltage regulator. It

supports an input voltage of 10 volts to 35 volts and output voltage of 5 volts. It



has a current rating of 1 amp although lower current models are available. Its

output voltage is fixed at 5.0V. The 7805 also has a built-in current limiter as a

safety feature. 7805 is manufactured by many companies, including National

Semiconductors and Fairchild Semiconductors.

The 7805 will automatically reduce output current if it gets too hot.The last two

digits represent the voltage; for instance, the 7812 is a 12-volt regulator. The

78xx series of regulators is designed to work in complement with the 79xx

series of negative voltage regulators in systems that provide both positive and

negative regulated voltages, since the 78xx series can't regulate negative

voltages in such a system.

Design specifications

=5V, =500mA, f=50HZ

Calculations

=

=10Ω

Ripple factor, =0.1

√ =>C=962.25

Choose C=1000 Transformer rating

= +

=20+

=20.25V = + 2( ) =20.25+ 2(0.6) =21.45

=

√ =13.47V Choose 15V-0-15V Transformer



CHAPTER-5

LIQUID CRYSTAL DISPLAY

LCD stands for Liquid Crystal Display. LCD is finding wide spread use

replacing LEDs (seven segment LEDs or other multi segment LEDs) because of

the following reasons:

1. The declining prices of LCDs.

2. The ability to display numbers, characters and graphics. This is in

contrast to LEDs, which are limited to numbers and a few characters.

3. Incorporation of a refreshing controller into the LCD, thereby relieving

the CPU of the task of refreshing the LCD. In contrast, the LED must be

refreshed by the CPU to keep displaying the data.

4. Ease of programming for characters and graphics.

5.1 LCD SCREEN

LCD screen consists of two lines with 16 characters each. Each character

consists of 5x7 dot matrix. Contrast on display depends on the power supply

voltage and whether messages are displayed in one or two lines. For that reason,

variable voltage 0-Vdd is applied on pin marked as Vee. Trimmer potentiometer

is usually used for that purpose. Some versions of displays have built in

backlight (blue or green diodes). When used during operating, a resistor for

current limitation should be used (like with any LE diode).



CHAPTER-6

RS-232

6.1 RS 232:

RS-232 is simple, universal, well understood and supported but it

has some serious shortcomings as a data interface. The standards to 256kbps or

less and line lengths of 15M (50 ft) or less but today we see high speed ports on

our home PC running very high speeds and with high quality cable maxim

distance has increased greatly. The rule of thumb for the length a data cable

depends on speed of the data, quality of the cable.

.

Sub-D15 Male Sub-D15 Female



6.1.1 APPLICATIONS:

TIA/EIA-232-F

Battery-Powered Systems

Terminals

Modems

Computers

ESD Protection Exceeds 2000 V Per

MIL-STD-883, Method 3015

Package Options Include Plastic

Small-Outline (D, DW) Packages and

Standard Plastic (N) DIPs



CHAPTER-7

GSM MODEM

7.1 THEORY

Unlike mobile phones, a GSM modem doesn’t have a keypad and display to

interact with. It just accepts certain commands through a serial interface and

acknowledges for those. These commands are called as AT commands. There

are lists of AT commands to instruct the modem to perform its functions. Every

command starts with "AT". That’s why they are called as AT commands. AT

stands for attention.



SMS Related AT Commands

AT It is used to test the connection.

AT+CMGF=1

It is used to instruct the modem to operate in text mode.

AT+CMGF=0 will instruct the modem to operate in

PDU mode.

AT+CMGS="mobile

number"

It is used to send a text message. It accepts the recipient

mobile number. As soon as this command is accepted

the modem waits for the message content. The text

message has to be sent sequentially and terminated by

the char 0x1A.

AT+CMGW="mobile

number"

It is used to store a message in the memory. After

execution it returns an index for the message stored. Eg:

AT+CMGW=1 . Here 1 is the index for the saved

message. Later this index is used to process the message

like deleting it or forwarding to the recipient number.

AT+CMGD=2

It is used to delete a message from the storage. The

index of the stored message is used to delete it. Above

command deletes the message with index 2.

In our simple project, the program waits for the mobile number to be entered

through the keyboard. When a ten digit mobile number is provided, the program

instructs the modem to send the text message using a sequence of AT

commands.

Testing your GSM modem

The GSM modem can be tested by connecting it with a PC. The modem

is equipped with a RS232 cable. Just use a Serial to USB converter and

connect it with the PC.

Now you can proceed with sending the commands to the modem using

any serial communication program like Hyperterminal, minicom etc.

Ensure the serial paramters are configured to 8N1 and the baudrate is set

to 9600bps.

For each command you send the modem acknowledges with a message.

Example: Just try sending "AT" to the modem. It sends back a result code

"OK" which states that the modem is responding. If it’s not working fine,

it sends "ERROR".



7.2 APPLICATIONS

1. All the parameters can be viewed on the mobile phone.

2. Most reliable.

3. Cost effective.

4. Supports innumerable sensors to the system.



CHAPTER-8

SOFTWARE IMPLEMENTATION

8.1 MAIN PROGRAM

#include<stdio.h>

#include<reg51.h>

#include <string.h>

#include "lcd.h"

#include "serial.h"

unsigned char idx=0,lc=0,rr=0,mno='1',okm,okl;

unsigned char buf[10];

unsigned char RCFLAG;

void main(void)

int i=0,k=0;

mno='1';

com_init_mm();

IE=0X90;

lcdinit();

MSDelay(100);

lcd_puts("Pls wait ....\0") ;

MSDelay(100);

MSDelay(100);



lcdcmd(0x01);

lcdinit();

MSDelay(100);

lcd_puts("HomeAutomation\0") ;

MSDelay(100);

MSDelay(100);

while(1)

lc=0; idx=0; rr=0;

ser_puts("AT+CMGL=\"ALL\"\r\n\0"); MSDelay(100);

MSDelay(100);

lcdcmd(LINE1);

//lcddata(okm);

//lcddata(okl);

if ((okm='O') && (okl=='K'))

lcdcmd(LINE1+2);

lcd_puts("nO mESSAGES") ;

else if (RCFLAG)

lcdcmd(LINE1+2);

lcdcmd(0x01);

lcd_puts(buf);

P1=buf[1] & 0X0F;

lcdcmd(LINE1); lcddata((lc&0X0F)+0x30);



lcdcmd(LINE1+2); lcddata(mno);

//----------------------

lc=0; idx=0; rr=0;

RCFLAG=0;

MSDelay(500);

Del_msg(mno);

lc=0; idx=0; rr=0; RCFLAG=0;

void rx(void) interrupt 4

unsigned char t;

if(RI)

t=SBUF;

RI=0;

if (rr<=25) rr++;

if (rr==10) mno=t;

if (rr==3) okm=t;

if (rr==4) okl=t;

if (t==0x0A) lc++ ;



if (( idx<=1)&&(lc==2)) buf[idx++]=t;

if ( lc==3)

RCFLAG=1;

buf[idx]=0;

else if (TI) TI=0;

`

8.2 LCD PROGRAM

#include<stdio.h>

#include<reg51.h>

#include "lcd.h"

void lcdcmd(unsigned char value)

lcdready();

ldata=value;

rs=0;

rw=0;

en=1;

MSDelay(1);

en=0;

return;



void lcddataxy(unsigned char x, unsigned char y, unsigned char value)

void lcddata( unsigned char value)

lcdready();

ldata=value;

rs=1;

rw=0;

en=1;

MSDelay(1);

en=0;

return;

void lcdready(void)

MSDelay(10);

return;

void MSDelay(unsigned int itime)

unsigned int i,j,k ;

for(k=0;k<itime;k++)

for(i=0;i<100;i++)



for(j=0;j<1;j++);

void lcdinit(void)

lcdcmd(0X38);

lcdcmd(0Xe);

lcdcmd(0X01);

lcdcmd(0X06);

lcdcmd(0X80);

lcdcmd(0X84);

void lcdPutHexbyte(unsigned char v)

unsigned char asc[] = "0123456789ABCDEF";

unsigned char t,c;

t= ((unsigned char) (v)) ;

c= (t>>4) &0x0f;

lcddata(asc[c]);

c=(t & 0x0f);

lcddata(asc[c]);



void lcd_puts(unsigned char *str) //Function to send string to LCD

int i=0;

while(str[i]!='\0')

lcddata(str[i]);

i++;

MSDelay(20);

void lcd_nputs(unsigned char *str,unsigned char n) //Function to send string to

LCD

int i=0;

for( i=0;(i<=n)&&( str[i]!=0);i++ )

while(str[i]!='\0')

lcddata(str[i]);

MSDelay(20);



8.3 SERIAL PROGRAM

#include<stdio.h>

#include<reg51.h>

#include <string.h>

#include "lcd.h"

#include "serial.h"

extern void com_init_mm(void)

TMOD=0x22;

TH1=-3;

SCON =0X50;

TR1= 1;

PS = 0;

TH0= 25 ;

TR0=1;

void Del_msg(unsigned char c)

unsigned char y;

y=c;

lcdcmd(LINE2);

lcd_puts("AT+CMGD=\0"); lcddata(y);MSDelay(100);

if (y=='1') ser_puts("AT+CMGD=1,0\0"); MSDelay(100);









ser_putc('\r');

ser_putc('\n');

MSDelay(500);

MSDelay(500);

MSDelay(500);

MSDelay(500);



MSDelay(500);

MSDelay(500);

MSDelay(500);

MSDelay(500);

MSDelay(500);

MSDelay(500);

void Send_sms(unsigned char * msg)

ser_puts("AT+CMGF=1\r\n\0");

MSDelay(500);

ser_puts("AT+CMGS=\"+917411461316\"\r\n\0");

ser_puts(msg);

ser_putc(CNT_Z);

MSDelay(500);

void ser_putc(unsigned char s)

SBUF=s;

extern void ser_puts(unsigned char * s)

unsigned char id=0,jj;

while (s[id]!='\0')

jj=s[id];

ser_putc(s[id]) ;

MSDelay(10);

id++;

CHAPTER 9



CONCLUSIONS

8.1 Conclusion The project “GSM BASED WIRELESS HOME AUTOMATION

SYSTEM” has been successfully designed and tested. Integrating features of all

the hardware components used have developed it. Presence of every module has

been reasoned out and placed carefully thus contributing to the best working of

the unit. Secondly, using highly advanced IC’s and with the help of growing

technology the project has been successfully implemented.

Embedded systems are emerging as a technology with high potential.

In the past decades micro processor based embedded system ruled the market.

The last decade witnessed the revolution of Microcontroller based embedded

systems. With regards to the requirements gathered the manual work and the

complexity in counting can be achieved with the help of electronic devices.



REFERENCES: 1. 8051-MICROCONTROLLER AND EMBEDDED SYSTEM. Mohd. Mazidi. 2. EMBEDDED SOFTWARE PRIMER David .E. Simon 3. The 8051 MICROCONTROLLER K.J.AYALA

home automation system using gsm

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