major project file 01

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1. INTRODUCTION

GSM Modem is mainly used to introduce the pre-paid concept in energy meter. GSM

which stands for Global System for Mobile Communication is widely used mobile

communication architecture used in most of the countries. With the help of GSM

modem one can embed a feature of pre-paid through mobile, also one can recharge

energy meter through mobile by SMS. The GSM modem loads the recharge amount

in one of the register of controller. For each pulses received at interrupt pin, the

controller decrement the content of the register which is equivalent to the recharged

amount left. If the content of the register falls below the threshold level, the controller

activates the GSM to send a message to the user which indicates that amount left in

the meter is low.

1.1 BACKGROUND

The traditional utility meter displays energy usage as an accumulation of counts

(KWH) presented to a display, which is used to calculate the monthly bill. It has

applications within the electricity, gas and water utility industries for domestic,

commercial and industrial applications. Sub metering is often used within a building,

retail or industrial facility where it is desirable to measure power consumption for

specific equipment, locations or sub-level accounts.

Reducing losses and waste, and adopting power efficient products and technology

can achieve this utilizing by remote management. Predicting energy usage remains

a key issue in an industry or Utility sector where downtime is unacceptable.

However, since power losses are not easy to identify, it is difficult to determine the

key culprits whether they are human users or power –hungry devices. In many cases

it is difficult to store energy e.g. electricity, which must be generated to 1ulfil

immediate demand. Predicting usage remains a key issue in an industry where

downtime is unacceptable, which is made difficult by slow access to the remote

meter readings.

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Fig. 1.1 Traditional Electric Meter

1.2 LITERATURE SURVEY AND RELATED WORKS

For this work existing meter reading techniques in India are analyzed and conducted

an extensive study on different energy measuring instruments available now. In

existing system either an electronic energy meter or an electro-mechanical meter is

fixed in the premise for measuring the usage. The meters currently in use are only

capable of recording kWh units. The kWh units used then still have to be recorded by

meter readers monthly, on foot. The recorded data need to be processed by a meter

reading company. For processing the meter reading, company needs to firstly link

each recorded power usage datum to an account holder and then determine the

amount owed by means of the specific tariff in use. Many systems built on various

platforms have been proposed by different research groups all over the world for

Automatic Meter Reading. There are two types of AMR systems, wire-based and

wireless. Power Line Carrier (PLC) and Telephone Line Network (optical/ cable) are

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wire-based are primarily designed for low power consumption. As they were

operating within a short range (power class- dependent: 1meter, 10 meters, 100

meters) this technique was not effective and implemented only in areas with high

population density. So a new approach of using an energy measurement technique

that encompasses the GSM network as a mean of transmitting energy data is more

relevant. The GSM/GPRS network offers most coverage in most developed and

developing countries. This method is also effective in rural areas, which are not

densely populated, and in which, most people do not have access to a fixed

telephone network. So in a country like India we need to focus more on this method

as it can be implemented very easily and effectively. According to the latest report by

researcher Gartner India’s mobile subscriber base should grow to 993 million by

2014, which expects the world’s fastest-growing mobile market to close 2010 with

more than 660 million subscribers.

India is the second-largest wireless market in the world after China with its 618

million mobile subscribers at end-May, according to data from the country’s telecoms

regulator. Mobile connections were at 525 million.

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1.3 PRESENT SCENARIO

Several transmission protocols in wired/wireless manner were introduced so far to

read digital meters remotely at different areas of India. The Digital watt-hour meters

are microprocessor based meters which replaced traditional electromechanical

meters.. Tele watt meters were implemented to transmit data on monthly basis to a

remote central office through a dedicated telephone line and a pair of modems. A

microprocessor/DSP based meter is used in this to measure the electricity

consumption of multiple users in a residential area. A master PC at the control centre

was used to send commands to a remote meter, which in turn transmitted data back,

using the Power Line Communication (PLC) technique. These techniques were

mainly implemented in areas that had a fixed telephone network. Bluetooth energy

meters were designed and implemented in some areas where several meters in

close proximity, communicated wirelessly with a Master PC

Fig. 1.2 A GSM BASED AUTOMATIC METER

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2. SYSTEM DISCRIPTION

The GSM based automatic electricity recharge system is very simple to operate and

is very effective in domestic use.

2.1 Design Description

In this system we have used Atmega8L microcontroller which has very simple

configuration and is easy to program. In the above system we have removed the

meter the load is directly connected to the controller as we know that the controller

signal is very low so it is amplified through an amplifier the load is connected to the

a.c supply though the relay. The microcontroller is so programmed that it will send

signal to the load only if it get a message from the GSM module

Fig. 2.1 CIRCUIT DIAGRAM

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2.2 APPLICATIONS

Working as a two-way communication with each meter—with intelligent

power meters and two way communications, the power company can manage

their peak loads better and offer incentives for customers to shift their power

usage to off –peak times.

Theft of service detection and prevention—Meter tampering is detected

instantly through the wireless network, making it much more difficult for

someone to steal the service.

Sub metering-Multi-tenant properties can provide individual user data to the

utility on a remote basis. The reduction of associated costs coupled with the

magnitude of the transmitted information can, in many cases, allow the utility

to offer its commercial customers new report –oriented services.

Down loading of all relevant data from the meter installed at consumer

premises or valves/checkpoints for pipelines.

Transform the data into signals suitable for transmission through the wireless

communication media.

Transmit info to information centers of a company based on the priority.

Transform the data into a format suitable for report generation, invoicing

confrom the computer system at any of above information centers.

Also transform the data into a format suitable for management information.

Alarm the above information centers in a selectable cycle, in case of

occurrence of deliberate tampering, pre specified parameters of system

anomaly/variations/irregularity, initiated from the CMU itself without waiting for

the interrogation from information centers.

The system will have security features to prevent any access by unauthorized

personnel to the data, hardware & software.

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The system will have security features for restricting personnel from

performing activities, which are not within their authorization.

The communication links between CMU & Boards various information

centers will be fully encrypted as per relevant Data Encryption Standards

Security of Data in transit will be provided by using standard protocols,

Error detection and correction protocols & security measures

Intelligent building applications –An area of overlap between intelligent

buildings and the AMR system is customer information coupled with the

variable rate structures. The AMR system can act as a specialized interface

between the building and the outside world.

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3. HARDWARE DISCRIPTION

In the proposed system the hardware used is very cheap and is very easily available

in market. The discussion of all the component used in the project in given below.

3.1 GSM MODULE

Global system for mobile communication (GSM) is a globally accepted

standard for digital cellular communication. GSM is the name of a

standardization group established in 1982 to create a common European

mobile telephone standard that would formulate specifications for a pan-

European mobile cellular radio system operating at 900 MHz It is estimated

that many countries outside of Europe will join the GSM Partnership.

GSM was devised as a cellular system specific to the 900 MHz band, called

“The Primary Band”. The primary band includes two sub bands of 25 MHz

each, 890 to 915 MHz and 935 MHz to 960 MHz GSM-PLMN has allocated

124 duplex carrier frequencies over the following bands of operate

Fig. 3.1 GSM Module

Uplink frequency band: 890 to 915 MHz(MS transmits , BTS receives).

Downlink frequency band: 935 to 960 MHz (BTS transmits, MS

receives). Carrier spacing : 200 KHZ

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3.2 LCD DISPLAY

LCD is a type of display used in digital watches and many portable

computers. LCD displays utilize to sheets of polarizing material with a liquid crystal

solution between them. An electric current passed through the liquid causes the

crystals to align so that light cannot pass through them. LCD technology has

advanced very rapidly since its initial inception over a decade ago for use in lap top

computers. Technical achievements has resulted in brighter displace, higher

resolutions, reduce response times and cheaper manufacturing process. The liquid

crystals can be manipulated through an applied electric voltage so that light is

allowed to pass or is blocked. By carefully controlling where and what wavelength

(color) of light is allowed to pass, the LCD monitor is able to display images. A

backlight provides LCD monitor’s brightness .Over the years many improvements

have been made to LCD to help enhance resolution, image, sharpness and

response times .One of the latest such advancement is applied to glass during acts

as switch allowing control of light at the pixel level, greatly improving LCD’s ability to

display small-sized fonts and image clearly. Other advances have allowed LCD’s to

greatly reduce liquid crystal cell response times. Response time is basically the

amount of time it takes for a pixel to “change colors”, in reality response time is the

amount of time it takes a liquid crystal cell to go from being active to inactive.

Fig. 3.2 LCD Display

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3.2.1 PIN DIAGRAM OF LCD

3.2.2 PIN DISCRIPTION OF LCD

Pin No

Function Name

1 Ground (0V) Ground

2 Supply voltage; 5V (4.7V – 5.3V) Vcc

3 Contrast adjustment; through a variable resistor VEE

4 Selects command register when low; and data register when high

Register Select

5 Low to write to the register; High to read from the register Read/write

6 Sends data to data pins when a high to low pulse is given Enable

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8-bit data pins

DB0

8 DB1

9 DB2

10 DB3

11 DB4

12 DB5

13 DB6

14 DB7

15 Backlight VCC (5V) Led+

16 Backlight Ground (0V) Led-

Fig 3.3 Pin Discription of LCD

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LED(LIGHT EMITTING DIODE)

A light-emitting diode (LED) is a two-lead semiconductor light source that

resembles a basic pn-junction diode, except that an LED also emits light. Whn an

LED's anode lead has a voltage that is more positive than its cathode lead by at least

the LED's forward voltage drop, current flows. Electrons are able to recombine with

holes within the device, releasing energy in the form of photons. This effect is called

electroluminescene, and the color of the light (corresponding to the energy of the

photon) is determined by the energy band gap of the semiconductor.

An LED is often small in area (less than 1 mm2), and integrated optical components

may be used to shape its radiation pattern.

Appearing as practical electronic components in 1962,the earliest LEDs emitted low-

intensity infrared light. Infrared LEDs are still frequently used as transmitting

elements in remote-control circuits, such as those in remote controls for a wide

variety of consumer electronics. The first visible-light LEDs were also of low intensity,

and limited to red. Modern LEDs are available across the visible, ultraviolet, and

infrared wavelengths, with very high brightness.

Fig. 3.4 LED Display

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3.3 MICROCONTROLLER

Microcontrollers these days are silent workers in many apparatus, ranging from the

washing machine to the video recorder. Nearly all of these controllers are mask

programmed and therefore are of very little use for applications that require the

programs to be changed during the course of execution. Even if the programs could

be altered, the information necessary to do so an instruction set, an assembler

language and description for the basic hardware is either very difficult to obtain or

are in adequate when it came to the issue of accessibility. A marked exception to the

above category is the ATMEGA8L micro controller belonging to the PIC family. This

microcontroller has features that seem to make it more accessible than any other

single chip microcontroller with a reasonable price tag. The ATMEGA8 an 8-bit

single chip microcontroller has got a powerful CPU optimized for control applications.

The ATMEGA8L is an 8 – bit single chip microcontroller. The ATMEGA8L is a

complete micro controller. There are 40 pins needed by the five-bidirectional ports.

Pins provide power, allow you to connect a crystal clock and provide a few timing

and control signals. The architecture includes the ALU, W register, the stack; a block

of registers. All these devices are connected to via internal 8-bit data bus. Each I/O

port is also connected to the 8-bit internal data bus through a series of registers.

These registers hold data during I/O transfers and control the I/O ports.

Fig3.5 Microcontroller

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3.3.1 ATMEGA 8L

Features

High-performance, Low-power AVR® 8-bit Microcontroller

Advanced RISC Architecture

130 Powerful Instructions – Most Single-clock Cycle Execution

32 x 8 General Purpose Working Registers

Fully Static Operation

Up to 16 MIPS Throughput at 16 MHz

On-chip 2-cycle Multiplier

High Endurance Non-volatile Memory segments

8K Bytes of In-System Self-programmable Flash program memory

512 Bytes EEPROM

1K Byte Internal SRAM

Write/Erase Cycles: 10,000 Flash/100,000 EEPROM

Data retention: 20 years at 85°C/100 years at 25°C

Optional Boot Code Section with Independent Lock Bits

In-System Programming by On-chip Boot Program

True Read-While-Write Operation

Programming Lock for Software Security

Peripheral Features

Two 8-bit Timer/Counters with Separate Prescaler, one Compare Mode

One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and

Capture Mode

Real Time Counter with Separate Oscillator

Three PWM Channels

8-channel ADC in TQFP and QFN/MLF package

Eight Channels 10-bit Accuracy

6-channel ADC in PDIP package

Six Channels 10-bit Accuracy

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Byte-oriented Two-wire Serial Interface

Programmable Serial USART

Master/Slave SPI Serial Interface

Programmable Watchdog Timer with Separate On-chip Oscillato

3.3.2 PIN DIAGRAM OF ATmega8L MICROCONTROLLER

Fig. 3.6 Pin Diagram of Atmega8L

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3.4 PASSIVE COMPONANTS

3.4.1 Resistors

A resistor is a passive two-terminal electrical component that implements electrical

resistances a circuit element. Resistors act to reduce current flow, and, at the same

time, act to lower voltage levels within circuits. Resistors may have fixed resistances

or variable resistances, such as those found in thermistors, varistors, trimmers,

photo resistors and potentiometers.

The current through a resistor is in direct proportion to the voltage across the

resistor's terminals. This relationship is represented by Ohm's law:

where I is the current through the conductor in units of amperes, V is the potential

difference measured across the conductor in units of volts, and R is the resistance of

the conductor in units of ohms (symbol: Ω).

The ratio of the voltage applied across a resistor's terminals to the intensity of current

in the circuit is called its resistance, and this can be assumed to be a constant

(independent of the voltage) for ordinary resistors working within their ratings.

Iin this module we use 1kilo ohm resistor with 5% tolerance.

Fig. 3.7 Resistors of 1kilo ohm

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The resistors are specified in terms of their resistance values, tolerance power rating

and thermal stability. By tolerance, we mean the allowed variation permitted in the

normal or marred value or the resistor.

3.4.2 CAPACITOR

A capacitor or condenser is a passive electronic component consisting of a pair

of conductors separate by a dielectric (insulator). When a (voltage) exists across the

conductors, an electric field is present in the dielectric. This field stores energy and

produces a mechanical force between the conductors. The effect is greatest when

there is a narrow separation between large areas of conductor, hence capacitor

conductors are often called plates.In practice, the dielectric between the plates

passes a small amount of leakage current. The conductors and leads introduce

an equivalent series resistance and the dielectric has an electric field strength limit

resulting in a breakdown voltage.

Sim 300 module of gsm consist 100 microfarad 16v capacitor & 470

microfarad 25v capacitor. This is a electrolytic capacitor. Capacitance is

expressed as the ratio of the electric charge (Q) on each conductor to the

potential difference (V) between them. The SI unit of capacitance is the farad

(F), which is equal to one coulomb per volt (1 C/V)

Fig3.8 Capacitor

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3.5 RELAY

Relay is an electromagnetic device which is used to isolate two circuits electrically

and connect them magnetically. They are very useful devices and allow one circuit to

switch another one while they are completely separate. They are often used to

interface an electronic circuit (working at a low voltage) to an electrical circuit which

works at very high voltage. For example, a relay can make a 5V DC battery circuit to

switch a 230V AC mains circuit. Thus a small sensor circuit can drive, say, a fan or

an electric bulb.

A relay switch can be divided into two parts: input and output. The input section has

a coil which generates magnetic field when a small voltage from an electronic circuit

is applied to it. This voltage is called the operating voltage. Commonly used relays

are available in different configuration of operating voltages like 6V, 9V, 12V, 24V

etc. The output section consists of contactors which connect or disconnect

mechanically. In a basic relay there are three contactors: normally open (NO),

normally closed (NC) and common (COM). At no input state, the COM is connected

to NC. When the operating voltage is applied the relay coil gets energized and the

COM changes contact to NO. Different relay configurations are available like SPST,

SPDT, DPDT etc, which have different number of changeover contacts.

Fig. 3.9 Relay

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3.6 AMPLIFIER

An electronic amplifier, amplifier, or (informally) amp is an electronic device that

increases the power of a signal. It does this by taking energy from a power supply

and controlling the output to match the input signal shape but with a larger

amplitude. In this sense, an amplifier modulates the output of the power supply.

There are four basic types of electronic amplifier: the voltage amplifier, the current

amplifier, the transconductance amplifier, and the transresistance amplifier. A further

distinction is whether the output is a linear or nonlinear representation of the input.

Amplifiers can also be categorized by their physical placement in the signal chain.

Amplifiers are described according to their input and output properties. The gain

may be specified as the ratio of output voltage to input voltage (voltage gain), output

power to input power (power gain), or some combination of current, voltage, and

power. In many cases, with input and output in the same unit, gain is unit less

(though often expressed in decibels (dB)).

ULN2003 is a high voltage and high current Darlington array IC. It contains

seven open collector darlington pairs with common emitters. A darlington pair

is an arrangement of two bipolar transistors.

ULN2003 belongs to the family of ULN200X series of ICs. Different versions

of this family interface to different logic families. ULN2003 is for 5V TTL,

CMOS logic devices. These ICs are used when driving a wide range of loads

and are used as relay drivers, display drivers, line drivers etc. ULN2003 is

also commonly used while driving Stepper Motors. Refer Stepper Motor

interfacing using ULN2003.

Fig. 3.10 Amplifier

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3.6.1 PIN DISCRIPTION OF ULN2003

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3.7 BUZZER

A buzzer or beeper is an audio signalling device, which may be mechanical,

electromechanical, or piezoelectric. Typical uses of buzzers and beepers include

alarm devices, timers and confirmation of user input such as a mouse click or

keystroke.

Early devices were based on an electromechanical system identical to an electric

bell without the metal gong. Similarly, a relay may be connected to interrupt its own

actuating current, causing the contacts to buzz. Often these units were anchored to a

wall or ceiling to use it as a sounding board. The word "buzzer" comes from the

rasping noise that electromechanical buzzers made.

Fig. 3.11 Buzzer

The buzzer produces a same noisy sound irrespective of the voltage variation

applied to it. It consists of piezo crystals between two conductors. When a potential

is applied across these crystals, they push on one conductor and pull on the other.

This, push and pull action, results in a sound wave. Most buzzers produce sound in

the range of 2 to 4 kHz.

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3.8 VOLTAGE REGULATOR

The 7805 voltage regulators employ built-in current limiting, thermal shutdown,

and safe-operating area protection which make them virtually immune to damage

from output overloads. 7805 is a three-terminal positive voltage regulator. With

adequate heat sinking, it can deliver in excess of 0.5A output current. Typical

applications would include local (on-card) regulators which can eliminate the noise

and degraded performance associated with single-point regulation. 7805 regulator

comes from the 78xx family of self-contained fixed linear voltage regulator integrated

circuits. The 78xx family is a very popular choice for many electronic circuits which

require a regulated power supply, due to their ease of use and relative cheapness.

When specifying individual ICs within this family, the xx is replaced with a two-digit

number, which indicates the output voltage the particular device is designed to

provide (for example, the 7805 voltage regulator has a 5 volt output, while the 7812

produces 12 volts). The 78xx line is positive voltage regulators, meaning that they

are designed to produce a voltage that is positive relative to a common ground.

There is a related line of 79xx devices which are complementary negative voltage

regulators. 78xx and 79xx ICs can be used in combination to provide both positive

and negative supply voltages in the same circuit, if necessary.

Input voltage (5V-18V)

Ground (0V)

Regulated output; 5V (4.8V-5.2V)

Fig. 3.12 7805 Voltage regulaor

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4. SOFTWARE DISCRIPTION

The software used in preparing the project is very easy to operate and is frequently

used in programming almost all the AT mega series microcontroller. The main

software used in programming the microcontroller is given below.

4.1 CODE VISION AVR

Code Vision Avr is a C cross-compiler, Integrated Development Environment,

and Automatic program generator designed Atmel AVR family of microcontrollers.

C cross-compiler- The c cross-compiler implements nearly all the elements of the

ANSI C language, as allowed by the AVR architecture with some features added to

take advantage of specificity of the AVR architecture and the embedded system

needs.

Integrated Development Environment- The IDE as built-in AVR Chip In-System

Programmer software that enables the automatic transfer of the program to the

microcontroller chip after successful compilation/assembly.

Fig. 4.1 Code Vision AVR Startup window

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Automatic program generator- Code Vision AVR also contains Code Wizard AVR

automatic program generator that allows you to write, in a matter of minutes, all the

code needed for implementing the following functions:

Input/output port initialization

External Interrupts initialization

Timer/ Counter initialization

Watchdog timer initialization

UART initialization

ADC initialization

LCD module initialization

SPI interface initialization, etc

Fig. 4.2 Code Vision AVR pin select window

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4.2 KHAZAMA SOFTWARE

The goals of this program is a nice small, fast, reliable and simple to use program.

You can set your settings according to your project. This steps will execute after you

push “Auto Program” button on the main window or press CTRL P shortcut.

From the latest version you can override chip signature check (for example for

ATMega48 and ATMega48PA chip signatures are different but with overriding sign

check you can program this chips truly). You can change 24 programming clock

speed too.

Fuses and Lock window help you to set settings for AVR chips. All settings are

documented and can select easily from combos or set directly from check boxes

Fig. 4.3 Khazama startup window

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5. COMPONENTS DETAILS

Component Used Specification Value

GSM Module SIM 300 950 Mhz

Microcontroller ATmega8L 8Kb Flash Memory

LM7805 Three Terminal Voltage Regulator

5V

Amplifier ULN2003 16 Pin

Relay Magnetic

Resistor 5% tolerance 1 kilo ohm

Capacitor 100,470 micro farad

16 V & 25V

Lcd display 16 pin

Led display Red colour 1.8 – 5 V

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6. SOURCE CODE

Chip type : ATmega8

Program type : Application

Clock frequency : 1.000000 MHz

Memory model : Small

External SRAM size : 0

Data Stack size : 256

*****************************************************/

#include <mega8.h>

#include <delay.h>

// Standard Input/Output functions

#include <stdio.h>

#include <stdlib.h>

static unsigned char m[100] ;

// Declare your global variables here

unsigned char ok[]={'A','T'};

unsigned char TEXT[]={'A','T','+','C','M','G','F','=','1'};

unsigned char read[]={'A','T','+','C','M','G','R','=','1'};

unsigned char q,v,i,k, n,en=13;

char c;

static unsigned char j=0;

void main(void)

{

// Declare your local variables here

// Port B initialization

// Func7=In Func6=In Func5=In Func4=In Func3=In Func2=In Func1=In Func0=In

// State7=T State6=T State5=T State4=T State3=T State2=T State1=T State0=T

PORTB=0x00;

DDRB=0x00;

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// Port C initialization



PORTC=0x00;

DDRC=0x00;

// Port D initialization



PORTD=0x00;

DDRD=0x00;

// Timer/Counter 0 initialization

// Clock source: System Clock

// Clock value: Timer 0 Stopped

// Mode: Normal top=FFh

// OC0 output: Disconnected

TCCR0=0x00;

TCNT0=0x00;

OCR0=0x00;




// Mode: Normal top=FFFFh

// OC1A output: Discon.

// OC1B output: Discon.

// Noise Canceler: Off

// Input Capture on Falling Edge

// Timer 1 Overflow Interrupt: Off

// Input Capture Interrupt: Off

// Compare A Match Interrupt: Off

// Compare B Match Interrupt: Off

TCCR1A=0x00;

TCCR1B=0x00;

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TCNT1H=0x00;

TCNT1L=0x00;

ICR1H=0x00;

ICR1L=0x00;

OCR1AH=0x00;

OCR1AL=0x00;

OCR1BH=0x00;

OCR1BL=0x00;




// Mode: Normal top=FFh

// OC2 output: Disconnected

ASSR=0x00;

TCCR2=0x00;

TCNT2=0x00;

OCR2=0x00;

// External Interrupt(s) initialization

// INT0: Off

// INT1: Off

// INT2: Off

MCUCR=0x00;

MCUCSR=0x00;

// Timer(s)/Counter(s) Interrupt(s) initialization

TIMSK=0x00;

// USART initialization

// Communication Parameters: 8 Data, 1 Stop, No Parity

// USART Receiver: On

// USART Transmitter: On

// USART Mode: Asynchronous

// USART Baud rate: 9600 (Double Speed Mode)

UCSRA=0x02;

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UCSRB=0x18;

UCSRC=0x86;

UBRRH=0x00;

UBRRL=0x0C;

// Analog Comparator initialization

// Analog Comparator: Off

// Analog Comparator Input Capture by Timer/Counter 1: Off

ACSR=0x80;

SFIOR=0x00;

for(i=0;i<2;i++){

putchar(ok[i]);

//delay_ms(1000);

}

putchar(en);

//delay_ms(5000);

for(v=0;v<9;v++){

putchar(TEXT[v]);

//delay_ms(1000);

}

putchar(en);

delay_ms(5000);

for(k=0;k<9;k++){

putchar(read[k]);

//delay_ms(1000);

}

putchar(en)

//delay_ms(5000);

for(q=0;q<100;q++){

c=getchar();

m[q]=c;

j++; }

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while (1)

{ for(n=0;n<100;n++)

putchar(m[n]);

if(PINC.0==1)

z=m[n];

else

(

z--;

if(PINC.1==1)

{

ldc_clear();

lcd_putsf("light mode on");

PORTB.1=1,PORTB.2=1;

delay_ms(5000);

PORTB.1=1,PORTB.2=0;

}

else

{

lcd_clear();

lcd_putsf("message mode on");

PORTB.1=0

}

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7. RESULT AND DICUSSION

The developed system is highly effective in the sense it is able to eliminate the

drawback of serial communication. i.e even though it lacks acknowledgement of the

sent SMS it is not affecting system performance. If a message is missing then also

as the system is accepting the cumulative value next time is willing, instant payment

by the consumer from anywhere in the world is also possible.

The project we have prepared is very effective in saving electricity by

reducing the theft in electricity. The problem in meter is also reduced by totally

removing the meter from electricity supply system. In the proposed system the load

(bulb) will illuminate only when we recharge it with certain amount as we do in

mobile, when the duration of recharged amount is finished it will turn off.

The system is firstly switched to recharge mode then we recharge it through

mobile as soon as the message is received by the microcontroller a message is

displayed in the LCD than we switch the system to the load mode as soon as the

load is ON the bulb start glowing and will glow till the recharge amount is finished.

7.1 RESULT IN STEPS

Step 1:-

The LCD will display the message LIGHT MODE ON Change 4 Msg, after receiving

message it shows “ WAITING FOR RECHARGE”.

Step 2:-

Then the system is recharged by using mobile by a specific amount.

Step 3:-

The LCD will display the message “MESSAGE RECIEVED”

Step 4:-

The load button is switched ON. The bulb will start glowing.

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SOME IMPORTANT RESULT

RECHAGE AMOUNT(Paise) DURATION OF BULB GLOW

60 60 sec

120 120 sec

If the system is recharged with 60 Paise the bulb will glow for 60 sec and similarly if

recharged with 120 the bulb will glow for 120 sec.

Fig. 6.1 GSM BASED ELECTRICITY RECHARGE SYSTEM

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8. CONCLUSION

The reliability and accuracy of a equipment are inversely proportional to the

number of component being used. The less number of the component more

reliability and accuracy can be achieved almost of the electronic component are

temperature and voltage variation dependent, so more number of component more

components. With the increase in number of components maintenance cost also

increases.

After the whole summery we can conclude that by using Gsm based electricity

recharge system we can save power in large amount and can also limit the theft in

electricity system and can also reduce the manpower.

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9. DATA SHEET

9.1 LM7805:-

35

9.2 ATmega8L:-

Pin Descriptions

Port B (PB7..PB0)

XTAL1/XTAL2/TOSC1/

TOSC2

Port B is an 8-bit bi-directional I/O port with internal pull-up

resistors (selected for each bit). The Port B output buffers have

symmetrical drive characteristics with both high sink and

source capability. As inputs, Port B pins that are externally

pulled low will source current if the pull-up resistors are

activated. The Port B pins are tri-stated when a reset condition

becomes active, even if the clock is not running.

Port C

(PC5..PC0)

Port C is an 7-bit bi-directional I/O port with internal pull-up

resistors (selected for each bit). The Port C output buffers have


source capability. As inputs, Port C pins that are externally

pulled low will source current if the pull-up resistors are

activated. The Port C pins are tri-stated when a reset condition

becomes active, even if the clock is not running.

PC6/RESET

If the RSTDISBL Fuse is programmed, PC6 is used as an I/O

pin. Note that the electrical characteristics of PC6 differ from

those of the other pins of Port C.

Port D (PD7..PD0)

Port D is an 8-bit bi-directional I/O port with internal pull-up

resistors (selected for each bit). The Port D output buffers have


source capability.

RESET Reset input. A low level on this pin for longer than the minimum pulse length will generate a reset, even if the clock is not running.

AVCC AVCC is the supply voltage pin for the A/D Converter, Port C

(3..0), and ADC (7..6). It should be externally connected to

VCC, even if the ADC is not used.

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9.3 ULN2003:- (AMPLIFIER)

37

10. REFERENCES

Patents and Journals:-

1. H. G. Rodney, C. H. Lee, V. H. Mok, “Automatic power Meter reading system

using GSM network”, The 8th International power engineering conference

(IPEC 2007), .

2. Mohan kumar, , “How Electronic Energy Meter Works?”, Retrieved March 1,

2012, from http:// dmohankumar.files.wordpress.com /2011/05/how-electronic-

energy-meter-works.pdf

3. Jain and Bagree , “A prepaid meter using mobile communication” ,

International Journal of Engineering, Science and 164 Technology, Vol. 3, No.

3, 2011, pp. 160-166.

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