TABLE OF CONTENTS

CHAPTER NO.

TITLE PAGE NO.

ABSTRACT 4TABLE OF CONTENTS 6LIST OF FIGURES 8LIST OF TABLES 9

CHAPTER 1 INTRODUCTION AND OBJECTIVES

1.1 INTRODUCTION 101.2 OBJECTIVES 101.3 EXISTING SYSTEM 111.4 PROPOSED SYSTEM 11

CHAPTER 2 SYSTEM DESCRIPTION

2.1 INTRODUCTION 122.2 BLOCK DIAGRAM 122.3 WORKING OF THE PROJECT 132.4 LITERATURE SURVEY 132.5 ADVANTAGES OF THE PROJECT 132.6 COST OF THE PROJECT 14

CHAPTER 3

2.6.1 HARDWARE COST 2.6.2 SOFTWARE COST

HARDWARE DESCRIPTION

1414

3.1 INTRODUCTION 153.2 GSM MODEM 3.2.1 DIAGRAM DESCRIPTION 3.2.2 MAX 232 CHIP 3.2.2.1 VOLTAGE LEVELS

15182222

3.3 FINGERPRINT SENSOR 3.3.1 FINGERPRINT RECOGNITION

2325

3.4 PERSONAL COMPUTER 3.4.1 MICROCONTROLLER 3.5 LIQUID CRYSTAL DISPLAY 3.5.1 SPECIFICATIONS 3.5.2 ADVANTAGES OF LCD

27 27 31 35 40

1

3.6 POWER SUPPLY 3.6.1 WORKING PRINCIPLE

41 42

CHAPTER 4 SOFTWARE DESCRIPTION

4.1 INTRODUCTION 45 4.1.1 COMMAND DESCRIPTION4.2 FINGERPRINT SCANNING CODING

4546

4.3 FINGERPRINT CODING4.4 SCANNING CODING

4955

CHAPTER 5 CONCLUSION

5.1CONCLUSION 575.2 REFERENCE 57

LIST OF FIGURES

2

FIGURE NO. TITLE PAGE

3.0 GENERAL BLOCK DIAGRAM 12

3.1 GSM CHARACTERISTIC CIRCUIT 17

3.2 GSM CIRCUIT DIAGRAM 18

3.3 MAX 232 CHIP 22

3.4 FINGERPRINT PATTERN 26

3.5 MINIATURE PATTERNS 27

3.6 MICROCONTROLLER PIN DIAGRAM 29

3.7 LCD PIN DIAGRAM 32

3.8 BLOCK DIAGRAM OF DC POWER SUPPLY 41

3.9 THREE TERMINAL VOLTAGE REGULATOR 44

LIST OF TABLES

3

TABLE NO. TITLE PAGE

1 RS 232 VOLTAGE LEVEL 23

2 PIN DESCRIPTION OF MICROCONTROLLER 30

CHAPTER-1

1. INTRODUCTION AND OBJECTIVES:

4

1.1 INTRODUCTION:

While the move towards the digital era is being accelerated every hour, biometrics

technologies have begun to affect people’s daily life more and more. Biometrics technologies

verify identity through characteristics such as fingerprints, faces, irises, retinal patterns, palm

prints, voice, hand-written signatures, and so on. These techniques, which use physical data,

are receiving attention as a personal authentication method that is more convenient than

conventional methods such as a password or ID cards. Biometric personal authentication uses

data taken from measurements. Such data is unique to the individual and remains so

throughout one’s life.

1.3 EXISTING SYSTEM

1.4 PROPOSED SYSTEM:

CHAPTER-2

2. SYSTEM DESCRIPTION:

5

GSM MODEM

PC FINGERPRINT

GSM MOBILE

LCD

REGULATED POWER SPPLY

2.1 INTRODUCTION:

A GSM modem is a specialized type of modem which accepts a SIM card, and operates over

a subscription to a mobile operator, just like a mobile phone. From the mobile operator

perspective, a GSM modem looks just like a mobile phone.

When a GSM modem is connected to a computer, this allows the computer to use the GSM

modem to communicate over the mobile network.  While these GSM modems are most

frequently used to provide mobile internet connectivity, many of them can also be used for

sending and receiving SMS and MMS messages.

2.2 BLOCK DIAGRAM:

Fig.3.0 GENERAL BLOCK DIAGRAM

2.3

WORKING OF THE PROJECT:

The device consists of GSM modem , Fingerprint Sensor, LCD display, Personal

Computer, Mobile, GSM antenna.

The attendance is marked by using sensor which is showed in LCD display.

It will check whether the finger print is matched which is stored in database and

simultaneously send the SMS which is received in respectable mobile through GSM

antenna.

6

The device is finger print protected , therefore only the people whose fingerprint have

been already stored will be supported for attendence.

2.4 LITERATURE SURVEY

“GSM based Attendance System” implements the emerging applications of the GSM

technology. Using GSM networks, a attendance system has been proposed that will act as an

embedded system which can monitor and mark the attendance.

The system allows the user to effectively monitor and mark the attendance and

equipments via the mobile phone set by sending commands in the form of SMS messages.

The main concept behind the project is sending the SMS. The type of the operation to be

performed depends on the nature of the SMS sent. The principle in which the project is based

is fairly simple. First, the sent SMS is stored and polled from the receiver mobile station and

sent to the intermediate hardware that we have designed according to the command received

in form of the sent message.

2.5 ADVANTAGES OF THE PROJECT:

Data will be accurate

Attendance management will be easy.

Lack of attendance will get minimized

Major problems will get reduced such as bunking of classes.

2.6 COST OF THE PROJECT:

Project cost can be divided in two ways and calculated as follows;

2.6.1 HARDWARE COST:

Hardware cost for our project can be considered as a moderate amount of money

spent. It does not fall under a cheap project neither it is a relatively smaller one.

However, having said that, the cost of the hardware components implemented does

amount to significant figures. We had to disrupt a phone set in order to receive the

7

SMS.the hardware expenses are not as significant when compared to it but they do

accumulate to a considerable amount. But taking into consideration that this is a one

time investment, the cost cannot be said to be too expensive.

2.6.2 SOFTWARE COST:

Software cost includes the cost of the required soft wares for our project. We did not

have to spend money in getting the necessary software for our project. The software

we used for our system is the free edition version and thus no money was put in it.

The involvement cost in our project is only the human labors, searching websites,

visiting different places and locations for gathering locations and not to mention the

cost of electricity that was consumed during the project completion time.

CHAPTER-3

3. HARDWARE DESCRIPTION:

3.1 INTRODUCTION:

We had described about the hardware components used in our project. In this project

we have explained about the hardware components such as Power supply, Personal

computer ,GSM modem, LCD display, GSM antenna , Fingerprint sensor.

3.2 GSM MODEM

8

A GSM modem is a specialized type of modem which accepts a SIM card, and

operates over a subscription to a mobile operator, just like a mobile phone. From the mobile

operator perspective, a GSM modem looks just like a mobile phone.

When a GSM modem is connected to a computer, this allows the computer to use the

GSM modem to communicate over the mobile network.  While these GSM modems are most

frequently used to provide mobile internet connectivity, many of them can also be used for

sending and receiving SMS and MMS messages.

A GSM modem can be a dedicated modem device with a serial, USB or Bluetooth

connection, or it can be a mobile phone that provides GSM modem capabilities. For the

purpose of this document, the term GSM modem is used as a generic term to refer to any

modem that supports one or more of the protocols in the GSM evolutionary family, including

the 2.5G technologies GPRS and EDGE, as well as the 3G technologies WCDMA, UMTS,

HSDPA and HSUPA.

A GSM modem exposes an interface that allows applications such as Now SMS to

send and receive messages over the modem interface. The mobile operator charges for this

message sending and receiving as if it was performed directly on a mobile phone. To perform

these tasks, a GSM modem must support an “extended AT command set” for

sending/receiving SMS messages, as defined in the ETSI GSM 07.05 and and 3GPP TS

27.005 specifications.

GSM modems can be a quick and efficient way to get started with SMS, because a

special subscription to an SMS service provider is not required. In most parts of the world,

GSM modems are a cost effective solution for receiving SMS messages, because the sender

is paying for the message delivery.

A GSM modem can be a dedicated modem device with a serial, USB or Bluetooth

connection, such as the Falcom Samba 75. (Other manufacturers of dedicated GSM modem

devices include Wavecom, Multitech and iTegno.  We’ve also reviewed a number of modems

on our technical support blog.) To begin, insert a GSM SIM card into the modem and

connect it to an available USB port on your computer.

A GSM modem could also be a standard GSM mobile phone with the appropriate

cable and software driver to connect to a serial port or USB port on your computer. Any

phone that supports the “extended AT command set” for sending/receiving SMS messages, as

defined in ETSI GSM 07.05 and/or 3GPP TS 27.005, can be supported by the Now SMS &

MMS Gateway. Note that not all mobile phones support this modem interface.

9

Due to some compatibility issues that can exist with mobile phones, using a dedicated GSM

modem is usually preferable to a GSM mobile phone. This is more of an issue with MMS

messaging, where if you wish to be able to receive inbound MMS messages with the

gateway, the modem interface on most GSM phones will only allow you to send MMS

messages. This is because the mobile phone automatically processes received MMS message

notifications without forwarding them via the modem interface.

It should also be noted that not all phones support the modem interface for sending and

receiving SMS messages. In particular, most smart phones, including Blackberries, iPhone,

and Windows Mobile devices, do not support this GSM modem interface for sending and

receiving SMS messages at all at all. Additionally, Nokia phones that use the S60 (Series 60)

interface, which is Symbian based, only support sending SMS messages via the modem

interface, and do not support receiving SMS via the modem interface.

3.2.1 GSM Characteristics

Global System for Mobile communications (GSM) is an international standard

for mobile communication. Originally, the acronym GSM stood for Groupe Spécial Mobile, a

group formed by the Conference of European Posts and Telegraphs (CEPT) in 1982 to

research the merits of a European standard for mobile telecommunications. Commercial

service using the GSM system did not actually start until 1991. Instead of using analog

service, GSM was developed as a digital system using TDMA technology.

Fig.3.1 GENERAL BLOCK DIAGRAM

10

The acknowledgement is based on GSM short messages from cell phones, and the equipment

used is SIM 300, is an industrial GSM module which provides four transmission modes

including voice, data, short message, and FAX. It works in frequency band GSM 900MHZ or

I800 MHZ, power voltage 3.4V to 4.5V and baud rate is 300 bps to 115 kbps, where between

1200 to 115 kbps is automatically configured.

Short Message Service (SMS) is a text messaging service component of phone,

web, or mobile communication systems, using standardized communications protocols that

allow the exchange of short text messages between fixed line or mobile phone devices. SMS

text messaging is the most widely used data application in the world, with 2.4 billion active

users, or 74% of all mobile phone subscribers. To communicate with an SMSC, an SMSC

protocol is required. Most of these SMSC protocols are proprietary to the company that

developed the SMSC. One widely used SMSC protocol is SMPP (Short Message Peer to

Peer). It was originally a proprietary SMSC protocol created by Logica (an SMSC vendor).

Now SMPP is an open SMSC protocol whose development is controlled by a non-profitable

organization SMS Forum.

11

Fig.3.2 GSM CHARACTERISTIC CIRCUIT

3.2.1 DIAGRAM DESCRIPTION

AT89S52  este un microcontroller compatibil cu marea familie Intel MCS-51.

AT89S52 este creat de către Atmel, lucru indicat de inițialele "AT". Acest microcontroler are

un consum scăzut, însă CMOS -ul de 8 biți îi dă performanțe ridicate, având o memorie

Flash internă de 8K Bytes. Acesta este realizat utilizând tehnologia cu memorie nevolatilă și

densitate ridicată ce aparține Atmel și este compatibil cu standardul 80C51. Chip-ul Flash

permite memoriei să fie reprogramată intern sau programată de către o memorie nevolatilă.

Prin combinarea a unui UCP de 8 biți cu memorie Flash programabilă pe nucleu monolitic,

Atmel AT89S52 este microcontroler foarte puternic ce are o flexibilitate ridicată și este astfel

soluția perfectă pentru multe aplicații embedded.

Un microcontroler este o structură electronică de dimensiune redusă, conținând în general un

procesor, o memorie și periferice de intrare/ieșire programabile. Aplicațiile in care se

utilizează microcontrolerele sunt cele de control automat, în domenii ca: producția auto,

dispozitive medicale, comandă la distanță, precum și multe altele de același gen. În 1976

Intel creează primul microcontroler din familia MCS denumit MCS 48, standardul MCS 51

12

aparând in 1980. În momentul de față Intel nu mai produce astfel de microcontrolere, insa

mari producători cum ar fi Atmel sau Infineon continuă creerea acestor dispozitive.

Principalele caracteristici ale acestui microcontroler sunt:

compatibilitate cu familia MCS 51;

UCP pe 8 biți la o frecvență de maxim 33MHz;

RAM: 256 Bytes;

memorie Flash: 8K Bytes;

32 de linii de programare pentru intrare/iesire cu caracter general;

8 surse de înterupere organizate pe 2 niveluri de priorități; 3 timere/countere de câte 16 biți; Watchdog Timer;

doi pointeri de date;

1 port serial (full duplex UART);

Interfață de programare ISP de 8K Bytes;

acceptă până la 10 000 de rescrieri;

conține oscilator;

durată de programare scurtă.

AT89S52 este un microcontroler cu 40 de pini, semnificația acestora fiind exprimată în

continuare. În paranteză este menționat numărul pinului ținând cont de faptul că pinul 1 este

în stânga sus, iar pinul 40 în dreapta sus.

Vcc(40): tensiune de alimentare;

GND(20): împământarea;

Port 0(39 - 32): Portul 0 este un port bidirecțional de intrare/iesire pe 8 biți. Ca port de ieșire,

fiecarui pin i se aloca 8 intrări TTL. Când pinii portului 0 sunt înscriși cu valoarea 1 logic,

aceștia pot fi folosiți ca intrări de impedanțe ridicate. Portul 0 poate de asemenea fi

configurat ca fiind partea mai puțin semnificativă de adrese sau date în timpul accesului la

programul extern și la datele din memorie. Portul 0 este de asemenea cel care primește codul

în timpul programării Flash și dă ca rezultat biții în urma programului de verificare.

Închiderea tranzistorului este obligatorie pe perioada verificării programului.

13

Port 1 (1-8): Portul 1 este de asemenea un port bidirecțional de intrare/ieșire având pull-up

intern(trazistorul este automat închis). Buferele de ieșire ale portului 1 pot suporta 4 intrări

TTL. Când portul 1 este înscris cu valoarea 1 logic, adică tranzistorul este închis, putem

utiliza portul pentru citire, altfel, pentru cazul în care tranzistorul este deschis utilizăm portul

pentru scriere. Portul 1 primește de asemenea partea mai puțin semnificativă a biților adresei

în timpul programării și verificării Flash. În plus, pinii 0 și 1 ai portului 1, pot fi configurați ca timer-e și counter-e, iar pinii 5, 6, 7 sunt utilizați pentru Interfața de Programare.

Port 2 (21-28): Portul 2 este, de asemenea, un port bidirecțional de intrare/iețire pe 8 biți cu

pull-up intern. Având același mod de funcționare ca și portul 1, în raport cu tranzistorul

existent. Portul 2 este cel care ne da biții cei mai semnificativi ai adresei in timpul extragerii

din memoria externă și în timpul accesului la memoria externă de date care utilizează adrese

de 16 biți. În acest mod de utilizare, Port-ul 2 utilizează un pull up intern puternic la emiterea

valorii 1 logic. În timpul accesului la memoria externă de date care utilizeză adrese de 8 biți, portul 2 este utilizat pentru Registrele Cu Funcții Speciale. Portul 2 de asemenea primește

partea cea mai semnificatică a biților de adresa și câteva semnale de control în timpul

programării și verificării Flash.

Port 3 (10-17): Portul 3 este, de asemenea, un port bidirecțional de intrare/ieșire pe 8 biți cu

pull-up intern, comportându-se la fel ca portul 1 si 2. Portul 3 primește semnale de control

pentru programarea și verifcarea memoriei Flash. Alte funcții speciale pe care le poate

îndeplini portul 3 sunt:

pinul 0 are ca funcție alternativă, intrare a portului serial (RXD);

pinul 1 este utilizat și ca ieșire a portului serial(TXD);

pinii 2 si 3 sunt utilizați pentru întreruperi externe(#INT0, #INT1);

pinii 4 și 5 pot fi utilizați alternativ ca timere(T0 și T1);

pinul 6 este utilizat pe post de semnal extern de scriere către memorie(#WR);

pinul 7 este utilizat pe post de semnal extern de citire din memorie(#RD).

RST (9): RST are rol de resetare a intrării. O valoare ridicată pe acest pin între două cicluri

mașină, în timp ce oscilatorul funcționează, resetează dispozitivul. Acest pin acționează high

pentru 98 de perioade ale oscilatorului după ce watchdog-ul se oprește. Pentru a dezactiva

aceasta caracteristică se utilizează bitul DISRTO din Regiștrii cu Funcții Speciale mai exact

14

de la adresa 8EH. În starea implicită a bitului DISRTO, caracteristica de RESET HIGH este

activă.

ALE/#PROG (30): Acronimul ALE provine de la Adress Latch Enable, iar acesta este cel

care comandă buffer-ul ce memorează partea mai puțin semnificativă a adresei. În timpul

programării memoriei Flash acest pin are rolul de programare a pulsurilor de intrare:

#PROG(Program Pulse Input). Pentru operațiile obișnuite , ALE emite la o perioada de timp

constantă, egala cu 1/6 din frecvența oscialtorului și poate fi utilizat pentru temporizări

externe sau pe post de ceas. Pentru doritori, funcția pe care ALE o execută poate fi

dezactivată prin setarea bitului Regiștrilor Speciali de la adresa 8EH cu valoarea 0 logic. Cu

acest bit setat, ALE este activ doar pentru instrucțiunile MOVX și MOVC. Dezactivarea

bitul ALE nu are nici un efect asupra microcontrolerului dacă este în modul extern de

execuție.

PSEN (29): Acronimul PSEN reprezintă Program Store Enable și reprezintă semnalul de

comandă pentru memoria program externă. Când AT89S52 execută cod al memoriei program

externe, #PSEN este activat de 2 ori pentru fiecare ciclu al mașinii, excepție când activarea

semnalului #PSEN este omisă în timpul accesului la memoria de date externă.

EA / VPP (31): Acronimul EA semnifică External Access Enable. #EA trebuie să fie legat la

GRD pentru a putea activa dispozitivul pentru extragerea de cod din memoria program

externă începând cu adresa 0000H până la adresa FFFFH.Pentru execuții interne de program

#EA trebuie sa fie legat la Vcc.

XTAL1 (19): XTAL1 este utilizat ca intrare a oscilatorului inversor amplificat și ca intrare

ceas a circuitului operațional.

XTAL2 (18): XTAL2 reprezintă ieșirea oscilatorului inversor amplificat.

WATCHDOG TIMER

Watchdog Timer(WDT) este utilizat ca o metodă de reconstituire în situații în care UCP-ul

este supus unor probleme software. WDT-ul constă într-un numărător pe 14 biți și un

Watchdog Timer Reset(WDTRST) ce se află în RFS. Implicit, WDT este dezactivat, pentru

activare, utilizatorul scrie 01EH și 0E1H succesiv în registrul WDTRST, adică în locația

0A6H a RFS-ului. Câns WDT este activ, el va incrementa fiecare ciclu mașină, cât timp

oscilatorul va rula. Perioada de pauză este dependentă de frecvența ceasului extern. Singura

15

modalitate de dezactivare a WDT-ului este prin resetare. Când WDT-ul depașește limita

maximă, va trimite un impuls RESET HIGH pinului de RST.

3.2.2 MAX232

Fig.3.3

The MAX232 is an integrated circuit, first created by Maxim Integrated Products, that

converts signals from an RS-232 serial port to signals suitable for use in TTL compatible

digital logic circuits. The MAX232 is a dual driver/receiver and typically converts the RX,

TX, CTS and RTS signals.

The drivers provide RS-232 voltage level outputs (approx. ± 7.5 V) from a single + 5 V

supply via on-chip charge pumps and external capacitors. This makes it useful for

implementing RS-232 in devices that otherwise do not need any voltages outside the 0 V to

+ 5 V range, as power supply design does not need to be made more complicated just for

driving the RS-232 in this case.

The receivers reduce RS-232 inputs (which may be as high as ± 25 V), to standard

5 V TTL levels. These receivers have a typical threshold of 1.3 V, and a typical hysteresis of

0.5 V.

The later MAX232A is backwards compatible with the original MAX232 but may operate at

higher baud rates and can use smaller external capacitors – 0.1 μF in place of the 1.0 μF

capacitors used with the original device.

The newer MAX3232 is also backwards compatible, but operates at a broader voltage range,

from 3 to 5.5 V.

Pin to pin compatible: ICL232, ST232, ADM232, HIN232.

3.2.2.1VOLTAGE LEVELS

16

It is helpful to understand what occurs to the voltage levels. When a MAX232 IC receives a

TTL level to convert, it changes a TTL Logic 0 to between +3 and +15 V, and changes TTL

Logic 1 to between -3 to -15 V, and vice versa for converting from RS232 to TTL. This can

be confusing when you realize that the RS232 Data Transmission voltages at a certain logic

state are opposite from the RS232 Control Line voltages at the same logic state. To clarify the

matter, see the table below. For more information see RS-232 Voltage Levels.

RS232 Line Type & Logic LevelRS232

Voltage

TTL Voltage to/from

MAX232

Data Transmission (Rx/Tx) Logic 0 +3 V to +15 V 0 V

Data Transmission (Rx/Tx) Logic 1 -3 V to -15 V 5 V

Control Signals (RTS/CTS/DTR/DSR) Logic

0-3 V to -15 V 5 V

Control Signals (RTS/CTS/DTR/DSR) Logic

1+3 V to +15 V 0 V

Table.1

3.3 FINGER FRINT SENSORS

A fingerprint  sensor is an electronic device used to capture a digital image of the

fingerprint pattern. The captured image is called a live scan. This live scan is digitally

processed to create a biometric template (a collection of extracted features) which is stored

and used for matching. This is an overview of some of the more commonly used fingerprint

sensor technologies.

17

Optical

Optical fingerprint imaging involves capturing a digital image of the print

using visible light. This type of sensor is, in essence, a specialized digital camera. The top

layer of the sensor, where the finger is placed, is known as the touch surface. Beneath this

layer is a light-emitting phosphor layer which illuminates the surface of the finger. The light

reflected from the finger passes through the phosphor layer to an array of solid state pixels

(a charge-coupled device) which captures a visual image of the fingerprint. A scratched or

dirty touch surface can cause a bad image of the fingerprint. A disadvantage of this type of

sensor is the fact that the imaging capabilities are affected by the quality of skin on the finger.

For instance, a dirty or marked finger is difficult to image properly. Also, it is possible for an

individual to erode the outer layer of skin on the fingertips to the point where the fingerprint

is no longer visible. It can also be easily fooled by an image of a fingerprint if not coupled

with a "live finger" detector. However, unlike capacitive sensors, this sensor technology is

not susceptible to electrostatic discharge damage. 

Ultrasonic

Ultrasonic sensors make use of the principles of medical ultrasonography in order

to create visual images of the fingerprint. Unlike optical imaging, ultrasonic sensors use very

high frequency sound waves to penetrate the epidermal layer of skin. The sound waves are

generated using piezoelectric transducers and reflected energy is also measured using

piezoelectric materials. Since the dermal skin layer exhibits the same characteristic pattern of

the fingerprint, the reflected wave measurements can be used to form an image of the

fingerprint. This eliminates the need for clean, undamaged epidermal skin and a clean sensing

surface.

Capacitance

Capacitance sensors utilize the principles associated with capacitance in order to

form fingerprint images. In this method of imaging, the sensor array pixels each act as one

plate of a parallel-plate capacitor, the dermal layer (which is electrically conductive) acts as

the other plate, and the non-conductive epidermal layer acts as a dielectric.

Passive capacitance

A passive capacitance sensor uses the principle outlined above to form an image of

the fingerprint patterns on the dermal layer of skin. Each sensor pixel is used to measure the

18

capacitance at that point of the array. The capacitance varies between the ridges and valleys

of the fingerprint due to the fact that the volume between the dermal layer and sensing

element in valleys contains an air gap. The dielectric constant of the epidermis and the area of

the sensing element are known values. The measured capacitance values are then used to

distinguish between fingerprint ridges and valleys.

Active capacitance

Active capacitance sensors use a charging cycle to apply a voltage to the skin before

measurement takes place. The application of voltage charges the effective capacitor. The

electric field between the finger and sensor follows the pattern of the ridges in the dermal

skin layer. On the discharge cycle, the voltage across the dermal layer and sensing element is

compared against a reference voltage in order to calculate the capacitance. The distance

values are then calculated mathematically, and used to form an image of the fingerprint.

Active capacitance sensors measure the ridge patterns of the dermal layer like the ultrasonic

method. Again, this eliminates the need for clean, undamaged epidermal skin and a clean

sensing surface.

ALGORITHM

Matching algorithms are used to compare previously stored templates of

fingerprints against candidate fingerprints for authentication purposes. In order to do this

either the original image must be directly compared with the candidate image or certain

features must be compared.

Pattern-based (or image-based) algorithms

Pattern based algorithms compare the basic fingerprint patterns (arch, whorl, and

loop) between a previously stored template and a candidate fingerprint. This requires that the

images be aligned in the same orientation. To do this, the algorithm finds a central point in

the fingerprint image and centers on that. In a pattern-based algorithm, the template contains

the type, size, and orientation of patterns within the aligned fingerprint image. The candidate

fingerprint image is graphically compared with the template to determine the degree to which

they match.

3.3.1FINGER PRINT RECOGNITION

Fingerprint recognition or fingerprint authentication refers to

the automated method of verifying a match between two human fingerprints. Fingerprints are

19

one of many forms of biometricsused to identify individuals and verify their identity. This

article touches on two major classes of algorithms (minutia and pattern) and

four sensor designs (optical, ultrasonic, passive capacitance, and active capacitance).

Patterns

The three basic patterns of fingerprint ridges are the arch, loop, and whorl:

arch: The ridges enter from one side of the finger, rise in the center forming an arc, and

then exit the other side of the finger.

losop: The ridges enter from one side of a finger, form a curve, and then exit on that same

side.

whorl: Ridges form circularly around a central point on the finger.

Scientists have found that family members often share the same general fingerprint patterns,

leading to the belief that these patterns are inherited.

The arch pattern.The loop pattern.

The whorl pattern.

Fig.3.4

Minutia features

The major Minutia features of fingerprint ridges are: ridge ending, bifurcation,

and short ridge (or dot). The ridge ending is the point at which a ridge terminates.

Bifurcations are points at which a single ridge splits into two ridges. Short ridges (or dots) are

ridges which are significantly shorter than the average ridge length on the fingerprint.

20

Minutiae and patterns are very important in the analysis of fingerprints since no two fingers

have been shown to be identical.

Ridge ending. Bifurcation. Short Ridge (Dot).

Fig.3.5

3.4.PERSONAL COMPUTER 

A personal computer (PC) is any general-purpose computer whose size,

capabilities, and original sales price make it useful for individuals, and which is intended to

be operated directly by an end-user with no intervening computer operator. This contrasted

with the batch processing or time-sharing models which allowed larger, more

expensive minicomputer and mainframe systems to be used by many people, usually at the

same time. Large data processing systems require a full-time staff to operate efficiently.

Software applications for personal computers include, but are not limited to, word

processing, spreadsheets, databases, Web browsers and e-mail clients, digital

media playback, games, and myriad personal productivity and special-purpose software

applications. Modern personal computers often have connections to the Internet, allowing

access to the World Wide Web and a wide range of other resources. Personal computers may

be connected to a local area network (LAN), either by a cable or a wireless connection. A

personal computer may be a desktop computer or a laptop, tablet, or a handheld PC.

3.4.1.Microcontroller

A microcontroller (sometimes abbreviated µC, uC or MCU) is a small computer

on a single integrated circuit containing a processor core, memory, and\

21

programmable input/output peripherals. Program memory in the form of NOR flash or OTP

ROM is also often included on chip, as well as a typically small amount of RAM.

Microcontrollers are designed for embedded applications, in contrast to

the microprocessors used in personal computers or other general purpose applications.

Microcontrollers are used in automatically controlled products and devices, such as

automobile engine control systems, implantable medical devices, remote controls, office

machines, appliances, power tools, toys and other embedded systems. By reducing the size

and cost compared to a design that uses a separate microprocessor, memory, and input/output

devices, microcontrollers make it economical to digitally control even more devices and

processes. Mixed signal microcontrollers are common, integrating analog components needed

to control non-digital electronic systems.

Some microcontrollers may use four-bit words and operate at clock rate frequencies as low as

4 kHz, for low power consumption (milliwatts or microwatts). They will generally have the

ability to retain functionality while waiting for an event such as a button press or other

interrupt; power consumption while sleeping (CPU clock and most peripherals off) may be

just nanowatts, making many of them well suited for long lasting battery applications. Other

microcontrollers may serve performance-critical roles, where they may need to act more like

a digital signal processor (DSP), with higher clock speeds and power consumption.

22

PIN DIAGRAM

:

23

Fig.3.6

3.4.2PIN DESCRIPTION

 Pin No  Function  Name

1

8 bit input/output port (P1) pins

P1.0

2 P1.1

3 P1.2

4 P1.3

5 P1.4

6 P1.5

7 P1.6

8 P1.7

9 Reset pin; Active high Reset

10 Input (receiver) for serial communication RxD

8 bit input/output

port (P3) pins

P3.0

11Output (transmitter) for serial

communicationTxD P3.1

12 External interrupt 1 Int0 P3.2

13 External interrupt 2 Int1 P3.3

14 Timer1 external input T0 P3.4

15 Timer2 external input T1 P3.5

16 Write to external data memory Write P3.6

17 Read from external data memory Read P3.7

18Quartz crystal oscillator (up to 24 MHz)

Crystal 2

19 Crystal 1

20 Ground (0V) Ground

21 8 bit input/output port (P2) pins

/

High-order address bits when interfacing with external memory

 

 P2.0/ A8

22  P2.1/ A9

23  P2.2/ A10

24  P2.3/ A11

25  P2.4/ A12

26  P2.5/ A13

27  P2.6/ A14

24

28  P2.7/ A15

29 Program store enable; Read from external program memory PSEN

30Address Latch Enable ALE

Program pulse input during Flash programming Prog

31External Access Enable;  Vcc for internal program executions EA

Programming enable voltage; 12V (during Flash programming) Vpp

32

8 bit input/output port (P0) pins

 

Low-order address bits when interfacing with external memory

 

 P0.7/ AD7

33  P0.6/ AD6

34  P0.5/ AD5

35  P0.4/ AD4

36  P0.3/ AD3

37  P0.2/ AD2

38  P0.1/ AD1

39  P0.0/ AD0

40 Supply voltage; 5V (up to 6.6V) Vcc

Table.2

3.5.LIQUID CRYSTAL DISPLAY (LCD)

A liquid crystal display (LCD) is a flat panel display, electronic visual

display, or video display that uses the light modulating properties of liquid crystals. Liquid

crystals do not emit light directly.

LCDs are available to display arbitrary images (as in a general-purpose

computer display) or fixed images which can be displayed or hidden, such as preset words,

digits, and 7-segment displays as in a digital clock. They use the same basic technology,

except that arbitrary images are made up of a large number of small pixels, while other

displays have larger elements.

LCDs are used in a wide range of applications including computer

monitors, televisions, instrument panels, aircraft cockpit displays, and signage. They are

common in consumer devices such as video players, gaming

devices, clocks, watches, calculators, andtelephones, and have replaced cathode ray

tube (CRT) displays in most applications. They are available in a wider range of screen sizes

than CRT and plasma displays, and since they do not use phosphors, they do not suffer image

burn-in. LCDs are, however, susceptible to image persistence.

25

The LCD is more energy efficient and can be disposed of more safely than a CRT. Its low

electrical power consumption enables it to be used in battery-powered electronic equipment.

It is an electronically modulated optical device made up of any number of segments filled

with liquid crystals and arrayed in front of a light source (backlight) or reflector to produce

images in color ormonochrome. Liquid crystals were first developed in 1888. By 2008,

worldwide sales of televisions with LCD screens exceeded annual sales of CRT units; the

CRT became obsolete for most purposes.

Fig.3.7

TWISTED NEMATIC (TN)

Twisted nematics displays contain liquid crystals that twist and untwist at

varying degrees to allow light to pass through. When no voltage is applied to a TN liquid

crystal cell, polarized light passes through the 90-degrees twisted LC layer. In proportion to

the voltage applied, the liquid crystals untwist changing the polarization and blocking the

light's path. By properly adjusting the level of the voltage almost any gray level or

transmission can be achieved.

IN PLANE SWITCHING (IPS)

In this method, the electrical field is applied through opposite electrodes on

the In-plane switching is an LCD technology that aligns the liquid crystals in a plane parallel

to the glass substrates. same glass substrate, so that the liquid crystals can be reoriented

(switched) in the same plane. This requires two transistors for each pixel instead of the single

transistor needed for a standard thin-film transistor (TFT) display. Before LG Enhanced IPS

was introduced in 2009, the additional transistors resulted in blocking more transmission

26

area, thus requiring a brighter backlight and consuming more power, making this type of

display less desirable for notebook computers. This newer, lower power technology can be

found in the Apple iMac, Macbook Pro,iPad, and iPhone 4, the Hewlett-

Packard EliteBook mobile workstations and the Nokia 701. Currently Panasonic is using an

enhanced version eIPS for their large size LCD-TV products as well as Hewlett-Packard in its

WebOS based TouchPad tablet.

IPS LCD vs AMOLED

LG claimed the smartphone LG Optimus Black with an IPS LCD (LCD NOVA)

has the brightness up to 700 nits, while the competitor has only IPS LCD with 518 nits and

double an Active-matrix OLED (AMOLED) display with 305 nits. LG also claimed the

NOVA display to be 50 percent more efficient than regular LCDs and to consume only 50

percent of the power of AMOLED displays when producing white on screen.When it comes

to contrast ratio, AMOLED display still performs best due to its underlying technology,

where the black levels are displayed as pitch black and not as dark gray. On August 24, 2011,

Nokia announced the Nokia 701 and also made the claim of the world's brightest display at

1000 nits. The screen also had Nokia's Clearblack layer, improving the contrast ratio and

bringing it closer to that of the AMOLED screens.

ADVANCED FRINGE SHIELD SWITCHING (AFFS)

It is Known as fringe field switching (FFS) until 2003, advanced fringe field

switching is similar to IPS or S-IPS offering superior performance and color gamut with high

luminosity. AFFS was developed by Hydis Technologies Co., Ltd, Korea (formally Hyundai

Electronics, LCD Task Force)

AFFS-applied notebook applications minimize color distortion while maintaining a wider

viewing angle for a professional display. Color shift and deviation caused by light leakage is

corrected by optimizing the white gamut which also enhances white/gray reproduction.

In 2004, Hydis Technologies Co., Ltd licensed AFFS to Japan's Hitachi Displays. Hitachi is

using AFFS to manufacture high-end panels. In 2006, HYDIS licensed AFFS to Sanyo Epson

Imaging Devices Corporation.

Shortly thereafter, Hydis introduced a high-transmittance evolution of the AFFS display,

called HFFS (FFS+).

27

Hydis introduced AFFS+ with improved outdoor readability in 2007. AFFS panels are mostly

utilized in the cockpits of latest commercial aircraft displays.

VERTICAL ALLIGNMENT (VA)

Vertical alignment displays are a form of LCDs in which the liquid crystals naturally

align vertically to the glass substrates. When no voltage is applied, the liquid crystals remain

perpendicular to the substrate creating a black display between crossed polarizers. When

voltage is applied, the liquid crystals shift to a tilted position allowing light to pass through

and create a gray-scale display depending on the amount of tilt generated by the electric field.

BLUE PHASE MODE

Blue phase mode LCDs have been shown as engineering samples early in

2008, but they are not in mass-production yet. The physics of blue phase mode LCDs suggest

that very short switching times (~1 ms) can be achieved, so time sequential color control can

possibly be realized and expensive color filters would be obsolete. For details refer to Blue

Phase Mode LCD.

QUALITY CONTROL

Some LCD panels have defective transistors, causing permanently lit or unlit

pixels which are commonly referred to as stuck pixels or dead pixels respectively.

Unlike integrated circuits (ICs), LCD panels with a few defective transistors are usually still

usable. Manufacturers' policies for the acceptable number of defective pixels vary greatly. At

one point, Samsung held a zero-tolerance policy for LCD monitors sold in Korea. As of 2005,

though, Samsung adheres to the less restrictive ISO 13406-2 standard. Other companies have

been known to tolerate as many as 11 dead pixels in their policies. Dead pixel policies are

often hotly debated between manufacturers and customers. To regulate the acceptability of

defects and to protect the end user, ISO released the ISO 13406-2 standard. However, not

every LCD manufacturer conforms to the ISO standard and the ISO standard is quite often

interpreted in different ways.

LCD panels are more likely to have defects than most ICs due to their larger

size. For example, a 300 mm SVGA LCD has 8 defects and a 150 mm wafer has only 3

defects. However, 134 of the 137 dies on the wafer will be acceptable, whereas rejection of

28

the whole LCD panel would be a 0% yield. In recent years, quality control has been

improved. An SVGA LCD panel with 4 defective pixels is usually considered defective and

customers can request an exchange for a new one.Some manufacturers, notably in South

Korea where some of the largest LCD panel manufacturers, such as LG, are located, now

have "zero defective pixel guarantee", which is an extra screening process which can then

determine "A" and "B" grade panels.Many manufacturers would replace a product even with

one defective pixel. Even where such guarantees do not exist, the location of defective pixels

is important. A display with only a few defective pixels may be unacceptable if the defective

pixels are near each other.

LCD panels also have defects known as clouding (or less commonly mura), which

describes the uneven patches of changes in luminance. It is most visible in dark or black areas

of displayed scenes.

ZERO-POWER (bistable) DISPLAY

The zenithal bistable device (ZBD), developed by QinetiQ (formerly DERA),

can retain an image without power. The crystals may exist in one of two stable orientations

("Black" and "White") and power is only required to change the image. ZBD Displays is a

spin-off company from QinetiQ who manufacture both grayscale and color ZBD devices.

Kent Displays has also developed a "no power" display that uses polymer

stabilized cholesteric liquid crystal (ChLCD). In 2009 Kent demonstrated the use of a

ChLCD to cover the entire surface of a mobile phone, allowing it to change colors, and keep

that color even when power is cut off.

In 2004 researchers at the University of Oxford demonstrated two new types of

zero-power bistable LCDs based on Zenithal bistable techniques.

Several bistable technologies, like the 360° BTN and the bistable cholesteric,

depend mainly on the bulk properties of the liquid crystal (LC) and use standard strong

anchoring, with alignment films and LC mixtures similar to the traditional monostable

materials. Other bistable technologies, e.g., BiNem technology, are based mainly on the

surface properties and need specific weak anchoring materials.

3.5.1.SPECIFICATION

Important factors to consider when evaluating an LCD:

29

Resolution versus range: Fundamentally resolution is the granularity (or number of

levels) with which a performance feature of the display is divided. Resolution is often

confused with range or the total end-to-end output of the display. Each of the major

features of a display has both a resolution and a range that are tied to each other but very

different. Frequently the range is an inherent limitation of the display while the resolution

is a function of the electronics that make the display work.

Spatial performance: LCDs come in only one size for a variety of applications and a

variety of resolutions within each of those applications. LCD spatial performance is also

sometimes described in terms of a "dot pitch". The size (or spatial range) of an LCD is

always described in terms of the diagonal distance from one corner to its opposite. This is

an historical remnant from the early days of CRT television when CRT screens were

manufactured on the bottoms of glass bottles, a direct extension of cathode ray tubes used

in oscilloscopes. The diameter of the bottle determined the size of the screen. Later, when

televisions went to a more square format, the square screens were measured diagonally to

compare with the older round screens.

The spatial resolution of an LCD is expressed by the number of columns and

rows of pixels (e.g., 1024×768). Each pixel is usually composed 3 sub-pixels, a red, a green,

and a blue one. This had been one of the few features of LCD performance that was easily

understood and not subject to interpretation. However there are newer schemes that

share sub-pixels among pixels and to add additional colors of sub-pixels. So going forward,

spatial resolution may now be more subject to interpretation.

One external factor to consider in evaluating display resolution is the resolution

of the viewer's eyes. Assuming 20/20 vision, the resolution of the eyes is about one minute of

arc. In practical terms that means for an older standard definition TV set the ideal viewing

distance was about 8 times the height (not diagonal) of the screen away. At that distance the

individual rows of pixels merge into a solid. If the viewer were closer to the screen than that,

they would be able to see the individual rows of pixels. When observed from farther away,

the image of the rows of pixels still merge, but the total image becomes smaller as the

distance increases. For an HDTV set with slightly more than twice the number of rows of

pixels, the ideal viewing distance is about half what it is for a standard definition set. The

higher the resolution, the closer the viewer can sit or the larger the set can usefully be sitting

at the same distance as an older standard definition display.

30

For a computer monitor or some other LCD that is being viewed from a very

close distance, resolution is often expressed in terms of dot pitch or pixels per inch. This is

consistent with the printing industry (another form of a display). Magazines, and other

premium printed media are often at 300 dots per inch. As with the distance discussion above,

this provides a very solid looking and detailed image. LCDs, particularly on mobile devices,

are frequently much less than this as the higher the dot pitch, the more optically inefficient

the display and the more power it burns. Running the LCD is frequently half, or more, of the

power consumed by a mobile device.

An additional consideration in spatial performance is viewing cone and aspect

ratio. The Aspect ratio is the ratio of the width to the height .Older, standard definition TVs

were 4:3. Newer High Definition televisions (HDTV) are 16:9, as are most new notebook

computers. Movies are often filmed in much different (wider) aspect ratios, which is why

there will frequently still be black bars at the top and bottom of an HDTV screen.

The Viewing Angle of an LCD may be important depending on its use or

location. The viewing angle is usually measured as the angle where the contrast of the LCD

falls below 10:1. At this point, the colors usually start to change and can even invert, red

becoming green and so forth. Viewing angles for LCDs used to be very restrictive however,

improved optical films have been developed that give almost 180 degree viewing angles from

left to right. Top to bottom viewing angles may still be restrictive, by design, as looking at an

LCD from an extreme up or down angle is not a common usage model and these photons are

wasted. Manufacturers commonly focus the light in a left to right plane to obtain a brighter

image here.

Temporal/timing performance: Contrary to spatial performance, temporal performance

is a feature where smaller is better. Specifically, the range is the pixel response time of an

LCD, or how quickly a sub-pixel's brightness changes from one level to another. For

LCD monitors, this is measured in (black to black) or (gray to gray). These different

types of measurements make comparison difficult. Further, this number is almost never

published in sales advertising.

Refresh rate or the temporal resolution of an LCD is the number of times per

second in which the display draws the data it is being given. Since activated LCD pixels do

not flash on/off between frames, LCD monitors exhibit no refresh-induced flicker, no matter

how low the refresh rate. High-end LCD televisions now feature up to 240 Hz refresh rate,

31

which requires advanced digital processing to insert additional interpolated frames between

the real images to smooth the image motion. However, such high refresh rates may not be

actually supported by pixel response times and the result can be visual artifacts that distort

the image in unpleasant ways.

Temporal performance can be further taxed if it is a 3D display. 3D displays work by

showing a different series of images to each eye, alternating from eye to eye. Thus a 3D

display must display twice as many images in the same period of time as a conventional

display, and consequently the response time of the LCD is more important. 3D LCDs with

marginal response times will exhibit image smearing.

These artifacts are most noticeable in a person's black and white vision (rod cells) than

in color vision (cone cells). Thus they will be more likely to see flicker or any sort of

temporal distortion in a display image by not looking directly at the display, because their

eyes' rod cells are mostly grouped at the periphery of their vision.

Color performance: There are many terms to describe color performance of an LCD.

They include color gamut which is the range of colors that can be displayed and color

depth which is the color resolution or the resolution or fineness with which the color

range is divided. Although color gamut can be expressed as three pairs of numbers, the

XY coordinates within color space of the reddest red, greenest green, and bluest blue, it is

usually expressed as a ratio of the total area within color space that a display can show

relative to some standard such as saying that a display was "120% of NTSC". NTSC is

the National Television Standards Committee, the old standard definition TV

specification. Color gamut is a relatively straight forward feature. However with clever

optical techniques that are based on the way humans see color, termed color

stretch. colors can be shown that are outside of the nominal range of the display. In any

case, color range is rarely discussed as a feature of the display as LCDs are designed to

match the color ranges of the content that they are intended to show. Having a color

range that exceeds the content is a useless feature.

Color depth or color support is sometimes expressed in bits, either as the number of bits

per sub-pixel or the number of bits per pixel. This can be ambiguous as an 8-bit color

LCD can be 8 total bits spread between red, green, and blue or 8 bits each for each color

in a different display. Further, LCDs sometimes use a technique called dithering which is

time averaging colors to get intermediate colors such as alternating between two different

32

colors to get a color in between. This doubles the number of colors that can be displayed;

however this is done at the expense of the temporal performance of the display. Dithering

is commonly used on computer displays where the images are mostly static and the

temporal performance is unimportant.

When color depth is reported as color support, it is usually stated in terms of

number of colors the LCD can show. The number of colors is the translation from the base 2-

bit numbers into common base-10. For example, 8-bit color is 2 to the 8th power, which is

256 colors. 24-bit color is 2 to the 24th power, or 256 x 256 x 256, a total of 16,777,216

colors. The color resolution of the human eye depends on both the range of colors being

sliced and the number of slices; but for most common displays the limit is about 28-bit

color LCD TVs commonly display more than that as the digital processing can introduce

color distortions and the additional levels of color are needed to ensure true colors.

There are additional aspects to LCD color and color management, such as white

point and gamma correction, which describe what color white is and how the other colors are

displayed relative to white. LCD televisions also frequently have facial recognition software,

which recognizes that an image on the screen is a face and both adjust the color and the focus

differently from the rest of the image. These adjustments can have important effects on the

consumer, but are not easily quantifiable; people like what they like and everyone does not

like the same thing. There is no substitute for looking at the LCD one is going to buy before

buying it. Portrait film, another form of display, has similar adjustments built in to it. Many

years ago, Kodak had to overcome initial rejection of its portrait film in Japan because of

these adjustments. In the U.S., people generally prefer a more colorful facial image than in

reality (higher color saturation). In Japan, consumers generally prefer a less saturated image.

The film that Kodak initially sent to Japan was biased in the wrong direction for Japanese

consumers. Television monitors have their built-in biases as well.

Brightness and contrast ratio: Contrast ratio is the ratio of the brightness of a full-on

pixel to a full-off pixel and, as such, would be directly tied to brightness if not for the

invention of the blinking backlight (or burst dimming). The LCD itself is only a light

valve, it does not generate light; the light comes from a backlight that is either a

florescent tube or a set of LEDs. The blinking backlight was developed to improve the

motion performance of LCDs by turning the backlight off while the liquid crystals were

in transition from one image to another. However, a side benefit of the blinking backlight

33

was infinite contrast. The contrast reported on most LCDs is what the LCD is qualified

at, not its actual performance. In any case, there are two large caveats to contrast ratio as

a measure of LCD performance.

The first caveat is that contrast ratios are measured in a completely dark

room. In actual use, the room is never completely dark, as one will always have the light from

the LCD itself. Beyond that, there may be sunlight coming in through a window or other

room lights that reflect off of the surface of the LCD and degrades the contrast. As a practical

matter, the contrast of an LCD, or any display, is governed by the amount of surface

reflections, not by the performance of the display.

The second caveat is that the human eye can only image a contrast ratio of a

maximum of about 200:1 Black print on a white paper is about 15–20:1. That is why viewing

angles are specified to the point where they fall below 10:1. A 10:1 image is not great, but is

discernible.

Brightness is usually stated as the maximum output of the LCD. In the CRT

era, Trinitron CRTs had a brightness advantage over the competition, so brightness was

commonly discussed in TV advertising. With current LCD technology, brightness, though

important, is usually similar from maker to maker and consequently is not discussed much,

except for laptop LCDs and other displays that will be viewed in bright sunlight. In general,

brighter is better, but there is always a trade-off between brightness and battery life in a

mobile device.

3.5.2.ADVANTAGES

Very compact and light.

Low power consumption. On average, 50-70% less energy is consumed than CRT

monitors.

No geometric distortion.

The possible ability to have little or no flicker depending on backlight technology.

Usually no refresh-rate flicker, as the LCD panel itself is usually refreshed at 200 Hz or

more, regardless of the source refresh rate.

Is very thin compared to a CRT monitor, which allows the monitor to be placed farther

back from the user, reducing close-focusing related eye-strain.

Razor sharp image with no bleeding/smearing when used at native resolution.

34

Emits less electromagnetic radiation than a CRT monitor.

Not affected by screen burn-in, though an identical but less severe phenomenon known

as image persistence is possible.

Can be made in almost any size or shape.

No theoretical resolution limit.

Can be made to large sizes (more than 24 inches) lightly and relatively inexpensively.

Masking effect: the LCD grid can mask the effects of spatial and grayscale quantization,

creating the illusion of higher image quality. As an inherently digital device, the LCD can

natively display digital data from a DVI or HDMI connection without requiring

conversion to analog, like a CRT would need.

Many LCD monitors run on an external 12v power supply, which means that (with a

proper cable) they can also be run directly on one of the computer's 12v power supply

outputs, removing the overhead and quiescent power consumption of the monitor's own

power supply. If the computer has a PFC power supply, this will increase the power

efficiency as well, as the cheap switching power supplies included with LCD monitors

rarely implement PFC. This is also convenient because the monitor will power on when

the computer is switched on, and will power off when the computer sleeps or is

shutdown.

3.6.POWER SUPPLY

The present chapter introduces the operation of power supply circuits built using filters,

rectifiers, and then voltage regulators. Starting with an ac voltage, a steady dc voltage is

obtained by rectifying the ac voltage, then filtering to a dc level, and finally, regulating to

obtain a desired fixed dc voltage. The regulation is usually obtained from an IC voltage

regulator unit, which takes a dc voltage and provides a somewhat lower dc voltage, which

remains the same even if the input dc voltage varies, or the output load connected to the dc

voltage changes.

35

Fig.3.8

A block diagram containing the parts of a typical power supply and the voltage at

various points in the unit is shown in figure 2.1. The ac voltage, typically 120 V rms, is

connected to a transformer, which steps that ac voltage down to the level for the desired dc

output. A diode rectifier then provides a full-wave rectified voltage that is initially filtered

by a simple capacitor filter to produce a dc voltage. This resulting dc voltage usually has

some ripple or ac voltage variation. A regulator circuit can use this dc input to provide a

dc voltage that not only has much less ripple voltage but also remains the same dc value

even if the input dc voltage varies somewhat, or the load connected to the output dc

voltage changes. This voltage regulation is usually obtained using one of a number of

popular voltage regulator IC units.

3.6.1 WORKING PRINCIPLE:

TRANSFORMER:

The potential transformer will step down the power supply voltage (0-230V) to (0-

6V) level. Then the secondary of the potential transformer will be connected to the precision

rectifier, which is constructed with the help of op–amp. The advantages of using precision

rectifier are it will give peak voltage output as DC, rest of the circuits will give only RMS

output.

BRIDGE RECTIFIER:

When four diodes are connected as shown in figure, the circuit is called as bridge

rectifier. The input to the circuit is applied to the diagonally opposite corners of the network,

and the output is taken from the remaining two corners.

Let us assume that the transformer is working properly and there is a positive

potential, at point A and a negative potential at point B. the positive potential at point A will

forward bias D3 and reverse bias D4.

36

The negative potential at point B will forward bias D1 and reverse D2. At this time

D3 and D1 are forward biased and will allow current flow to pass through them; D4 and D2

are reverse biased and will block current flow.

The path for current flow is from point B through D1, up through RL, through D3,

through the secondary of the transformer back to point B. this path is indicated by the solid

arrows. Waveforms (1) and (2) can be observed across D1 and D3.

One-half cycle later the polarity across the secondary of the transformer reverse,

forward biasing D2 and D4 and reverse biasing D1 and D3. Current flow will now be from

point A through D4, up through RL, through D2, through the secondary of T1, and back to

point A. This path is indicated by the broken arrows. Waveforms (3) and (4) can be observed

across D2 and D4. The current flow through RL is always in the same direction. In flowing

through RL this current develops a voltage corresponding to that shown waveform (5). Since

current flows through the load (RL) during both half cycles of the applied voltage, this bridge

rectifier is a full-wave rectifier.

One advantage of a bridge rectifier over a conventional full-wave rectifier is that with a given

transformer the bridge rectifier produces a voltage output that is nearly twice that of the

conventional full-wave circuit.

This may be shown by assigning values to some of the components shown in views A

and B. assume that the same transformer is used in both circuits. The peak voltage developed

between points X and y is 1000 volts in both circuits. In the conventional full-wave circuit

shown—in view A, the peak voltage from the center tap to either X or Y is 500 volts. Since

only one diode can conduct at any instant, the maximum voltage that can be rectified at any

instant is 500 volts.

The maximum voltage that appears across the load resistor is nearly-but never

exceeds-500 v0lts, as result of the small voltage drop across the diode. In the bridge rectifier

shown in view B, the maximum voltage that can be rectified is the full secondary voltage,

which is 1000 volts. Therefore, the peak output voltage across the load resistor is nearly 1000

volts. With both circuits using the same transformer, the bridge rectifier circuit produces a

higher output voltage than the conventional full-wave rectifier circuit.

IC VOLTAGE REGULATORS:

Voltage regulators comprise a class of widely used ICs. Regulator IC units contain the

circuitry for reference source, comparator amplifier, control device, and overload protection

all in a single IC. Although the internal construction of the IC is somewhat different from that

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described for discrete voltage regulator circuits, the external operation is much the same. IC

units provide regulation of either a fixed positive voltage, a fixed negative voltage, or an

adjustably set voltage.

A power supply can be built using a transformer connected to the ac supply line to step

the ac voltage to a desired amplitude, then rectifying that ac voltage, filtering with a capacitor

and RC filter, if desired, and finally regulating the dc voltage using an IC regulator. The

regulators can be selected for operation with load currents from hundreds of milli amperes to

tens of amperes, corresponding to power ratings from milliwatts to tens of watts.

THREE-TERMINAL VOLTAGE REGULATORS:

The basic connection of a three-terminal voltage regulator IC to a load. The fixed

voltage regulator has an unregulated dc input voltage, Vi, applied to one input terminal, a

regulated output dc voltage, Vo, from a second terminal, with the third terminal connected to

ground. For a selected regulator, IC device specifications list a voltage range over which the

input voltage can vary to maintain a regulated output voltage over a range of load current.

The specifications also list the amount of output voltage change resulting from a change in

load current (load regulation) or in input voltage (line regulation).

Fig 3.9

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A fixed three-terminal voltage regulator has an unregulated dc input voltage, Vi,

applied to one input terminal, a regulated dc output voltage, Vo, from a second terminal, with

the third terminal connected to ground.

The series 78 regulators provide fixed positive regulated voltages from 5 to 24 volts.

Similarly, the series 79 regulators provide fixed negative regulated voltages from 5 to 24

volts.

CHAPTER -4

4.1.SOFTWARE DESCRIPTION

4.1.1COMMAND DESCRIPTION:

AT+CMGR -Read new message from a given memory location.

AT+CMGS -Send message to a given recipient.

AT+CMGD -Delete message.

AT -Check if serial interface and GSM modem is working.

ATE0-Turn echo off, less traffic on serial line.

AT+CNMI-Display of new incoming SMS.

AT+CPMS -Selection of SMS memory.

AT+CMGF -SMS string format, how they are compressed.

READ MESSAGE AT+CMGR)

The “AT+CMGR” command is used to read a message from a given memory

location.

Execution of “AT+CMGR” returns a message at [index] from selected memory [M1].

The status of the message and the entire compressed message (PDU) is returned.

To get any useful information out of the compressed message it should be

decompressed.

SEND MESSAGE(AT+CMGS)

This command enables the user to send SMS messages.

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Describes how to build such messages. How to include user defined text and recipient

telephone number. After the user defined fields are set, the message can be

compressed and sent using the “AT+CMGS” command.

DELETE MESSAGE (AT+CMGD)

This command is used to delete a received stored message from [M1]

4.2.FOR FINGERPRINT SCANNING CODING

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Windows.Forms;using System.IO;using System.Data.OleDb;

namespace FPStudentAttandance{ class DataBase { public bool AddStudent(int Id, String Name, String DepartMent, String DOB, String MobileNumnber, String Address, int FPId) { bool retval = false; try { String strPath = Path.GetDirectoryName(Application.ExecutablePath); String Connstr = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source = " + strPath + "\\StudentDetails.mdb";

String strQuery = "INSERT INTO Student VALUES(" + Id + ",'" + Name + "','" + DepartMent + "','" + DOB + "','" + MobileNumnber + "','" + Address + "'," + FPId + ")"; OleDbConnection conn = new OleDbConnection(Connstr); conn.Open(); OleDbCommand cmd = new OleDbCommand(strQuery, conn); cmd.ExecuteNonQuery(); conn.Close(); retval = true; } catch (Exception ex) { }

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return retval; }

public bool GetStudentInfo(int Id, ref int FpId, ref String Dt, ref String Mobilenumber) { bool retavl = false; try { String strPath = Path.GetDirectoryName(Application.ExecutablePath); String Connstr = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source = " + strPath + "\\StudentDetails.mdb"; String strQuery = "SELECT [FPId], [DOB], [MobileNumber] FROM Student WHERE Id =" + Id; OleDbConnection conn = new OleDbConnection(Connstr); conn.Open(); OleDbCommand cmd = new OleDbCommand(strQuery, conn); OleDbDataReader Reader = cmd.ExecuteReader(); if(Reader.Read()) { FpId = int.Parse(Reader[0].ToString()); Dt = Reader[1].ToString(); Mobilenumber = Reader[2].ToString(); retavl = true; } conn.Close(); } catch(Exception ex) {

}

return retavl; }

public bool isStudentIn(int Id) { bool retavl = false; try { String strPath = Path.GetDirectoryName(Application.ExecutablePath); String Connstr = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source = " + strPath + "\\StudentDetails.mdb"; String strQuery = "SELECT * from Attandance WHERE Id = " + Id + " AND [in] = 1 AND Updated='" + DateTime.Today.ToString("dd-MM-yyyy") + "'"; OleDbConnection conn = new OleDbConnection(Connstr); conn.Open(); OleDbCommand cmd = new OleDbCommand(strQuery, conn); OleDbDataReader Reader = cmd.ExecuteReader(); if (Reader.Read())

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retavl = true; conn.Close();

} catch (Exception ex) {

} return retavl; }

public bool insertAttdancein(int Id, int inn, int outt, int late, String dt, String Status) { bool retval = false; try { String strPath = Path.GetDirectoryName(Application.ExecutablePath); String Connstr = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source = " + strPath + "\\StudentDetails.mdb";

String strQuery = "INSERT INTO Attandance VALUES(" + Id + ",'" + dt + "'," + inn + "," + outt + "," + late + ",'" + Status + "')"; OleDbConnection conn = new OleDbConnection(Connstr); conn.Open(); OleDbCommand cmd = new OleDbCommand(strQuery, conn); cmd.ExecuteNonQuery(); conn.Close(); retval = true; } catch (Exception ex) { }

return retval; }

public bool updateAttdanceout(int Id) { bool retval = false; try { String strPath = Path.GetDirectoryName(Application.ExecutablePath); String Connstr = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source = " + strPath + "\\StudentDetails.mdb";

String strQuery = "UPDATE Attandance SET [Out]=1 WHERE Id="+ Id +" AND Updated='"+ DateTime.Today.ToString("dd-MM-yyyy")+"'"; OleDbConnection conn = new OleDbConnection(Connstr); conn.Open(); OleDbCommand cmd = new OleDbCommand(strQuery, conn);

42

cmd.ExecuteNonQuery(); conn.Close(); retval = true; } catch (Exception ex) { }

return retval; } }

}

4.3.FOR FINGERPRINT CODING

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;using System.IO;using System.IO.Ports;

using Neurotec.Biometrics;using Neurotec.Gui;

namespace FPStudentAttandance{public partial class frmAttandeance : Form{Neurotec.Biometrics.Nffv engine = null;Nffv _engine;List<NffvUser> lstEngineUser;SerialPort sPort;

public frmAttandeance(Nffv engine){_engine = engine;InitializeComponent();}

private void addStudentToolStripMenuItem_Click(object sender, EventArgs e){

43

pnlAdd.Visible = true;lblTime.Visible = false;cmbCom.Visible = false;btnStart.Visible = false;

pnlAdd.Top = 40;this.Width = 712;this.Height = 550;}

private void frmAttandeance_Load(object sender, EventArgs e){

string[] ports = SerialPort.GetPortNames();if (ports.Length > 0){foreach (string port in ports){cmbCom.Items.Add(port);}cmbCom.SelectedIndex = 0;}

pnlAdd.Visible = false;this.Width = 712;this.Height = 350;

lstEngineUser = new List<NffvUser>();

foreach (NffvUser engineUser in _engine.Users)lstEngineUser.Add(engineUser);

lblTime.Text = DateTime.Now.ToString("dd-MM-yyyy HH:mm:ss"); ;timer1.Interval = 1000;timer1.Start();

}

internal class EnrollmentResult{public NffvStatus engineStatus;public NffvUser engineUser;};

private void doEnroll(object sender, DoWorkEventArgs args){EnrollmentResult enrollmentResults = new EnrollmentResult();enrollmentResults.engineUser = _engine.Enroll(20000, out enrollmentResults.engineStatus);

44

args.Result = enrollmentResults;}

private void CancelScanningHandler(object sender, EventArgs e){_engine.Cancel();}

private void timer1_Tick(object sender, EventArgs e){lblTime.Text = DateTime.Now.ToString("dd-MM-yyyy HH:mm:ss"); ;}

private void checlkAttendanceToolStripMenuItem_Click(object sender, EventArgs e){lblTime.Visible = true;pnlAdd.Visible = false;cmbCom.Visible = true;btnStart.Visible = true;

this.Width = 712;this.Height = 350;}

private void btnAdd_Click(object sender, EventArgs e){if (!isTextboxempty(txtStudentId, "Student Id"))return;

if (!isTextboxempty(txtName, "Student Name"))return;

if (!isTextboxempty(txtDepartment, "DepartMent"))return;

if (!isTextboxempty(txtMobile, "Mobile Number"))return;

if (!isTextboxempty(txtAddress, "Address"))return;

try{RunWorkerCompletedEventArgs taskResult = BusyForm.RunLongTask("Waiting for fingerprint ...", new DoWorkEventHandler(doEnroll),false, null, new EventHandler(CancelScanningHandler));EnrollmentResult enrollmentResult = (EnrollmentResult)taskResult.Result;if (enrollmentResult.engineStatus == NffvStatus.TemplateCreated){NffvUser engineUser = enrollmentResult.engineUser;

45

lstEngineUser.Add(engineUser);

PicStudentFingerPrint.Image = engineUser.GetBitmap();

int Id = int.Parse(txtStudentId.Text);String Name = txtName.Text;String Departmewnt = txtDepartment.Text;String MobileNumber = txtMobile.Text;String Adress = txtAddress.Text;Adress = Adress.Replace("\r\n", "-");DataBase db = new DataBase();int FPId = engineUser.Id;if (!db.AddStudent(Id, Name, Departmewnt, dtDate.Value.Date.ToString("dd-MM-yyyy"), MobileNumber, Adress, FPId)){MessageBox.Show("Falied to Add Student");return;}

ClearAllData();}else{NffvStatus engineStatus = enrollmentResult.engineStatus;MessageBox.Show(string.Format("Enrollment was not finished. Reason: {0}", engineStatus));}}catch (Exception ex){MessageBox.Show(ex.Message);}

}

public void ClearAllData(){txtStudentId.Text = "";txtName.Text = "";txtDepartment.Text = "";txtMobile.Text = "";txtAddress.Text = "";}

private void txtId_KeyPress(object sender, KeyPressEventArgs e){if (char.IsDigit(e.KeyChar) || char.IsControl(e.KeyChar))e.Handled = false;

46

elsee.Handled = true;

}

public bool isTextboxempty(TextBox txt, String strName){String str = txt.Text;str.Trim();if (str.Length <= 0){MessageBox.Show(strName + "Should not be empty");txt.Focus();return false;}return true;}

private void txtStudentId_KeyPress(object sender, KeyPressEventArgs e){if (char.IsDigit(e.KeyChar) || char.IsControl(e.KeyChar))e.Handled = false;elsee.Handled = true;}

internal class VerificationResult{public NffvStatus engineStatus;public int score;};

private void doVerify(object sender, DoWorkEventArgs args){VerificationResult verificationResult = new VerificationResult();verificationResult.score = _engine.Verify((NffvUser)args.Argument, 20000, out verificationResult.engineStatus);args.Result = verificationResult;}

private void btnCheck_Click(object sender, EventArgs e){bool blnIdFound = false;try{

if (!isTextboxempty(txtId, "Student Id"))return;

int Id = int.Parse(txtId.Text);

47

DataBase db = new DataBase();int FpId = 0;String dt = "";String Mobilenumber = "";if (!db.GetStudentInfo(Id, ref FpId, ref dt, ref Mobilenumber)){MessageBox.Show("Student Id Not Found");return;}

foreach (NffvUser engUser in lstEngineUser){if (FpId == engUser.Id){blnIdFound = true;

RunWorkerCompletedEventArgs taskResult = BusyForm.RunLongTask("Waiting for fingerprint ...", new DoWorkEventHandler(doVerify),false, engUser, new EventHandler(CancelScanningHandler));VerificationResult verificationResult = (VerificationResult)taskResult.Result;if (verificationResult.engineStatus == NffvStatus.TemplateCreated){if (verificationResult.score > 0){if (!db.isStudentIn(Id)){String strStatus = "Present";int Late = 0;DateTime t1 = Convert.ToDateTime(DateTime.Now);DateTime t2 = Convert.ToDateTime("12:30 PM");if (t1 > t2){MessageBox.Show("You are late");strStatus = "Late";Late = 1;}

String strDob = dt;String strToday = DateTime.Today.ToString("dd-MM-yyyy");if (strDob == strToday){DOB frm = new DOB();frm.ShowDialog();}

sPort.WriteLine("AT+CMGF=1");sPort.WriteLine("AT+CMGS=" + Mobilenumber + "\n");sPort.WriteLine("your son present in college" + (char)26);

48

if (!db.insertAttdancein(Id, 1, 0, Late, DateTime.Today.ToString("dd-MM-yyyy"), strStatus)){MessageBox.Show("Failed to Upadte Student Attandance inn");return;

}}else{if (!db.updateAttdanceout(Id)){MessageBox.Show("Failed to Upadte Student Attandance OUT");return;}

}}else{MessageBox.Show(string.Format("{0} not verified.\r\nFingerprints do not match. Score: {1}" + verificationResult.score));}}

else{MessageBox.Show(string.Format("Verification was not finished. Reason: {0}", verificationResult.engineStatus));}}}

if (blnIdFound == false){MessageBox.Show("Please Add the sudent");}}catch (Exception ex){MessageBox.Show(ex.Message);}

}

private void btnStart_Click(object sender, EventArgs e){SString str = cmbCom.Text;sPort = new SerialPort(str, 9600);sPort.Open();}

49

}}

4.4.FOR SCANNING CODING

using System;using System.Collections.Generic;using System.Linq;using System.Windows.Forms;

namespace FPStudentAttandance{static class Program{/// <summary>/// The main entry point for the application./// </summary>[STAThread]static void Main(){Application.EnableVisualStyles();Application.SetCompatibleTextRenderingDefault(false);

Neurotec.Biometrics.Nffv engine = null;try{try{engine = new Neurotec.Biometrics.Nffv("FingerprintDB.CSharpSample.dat", "", "Suprema");}catch (Exception){

MessageBox.Show("Failed to initialize Nffv or create/load database.\r\n" +"Please check if:\r\n - Provided password is correct;\r\n - Database filename is correct;\r\n" +" - Scanners are used properly.\r\n", "Nffv C# Sample", MessageBoxButtons.OK, MessageBoxIcon.Error);return;}

//Application.Run(new frmMain(engine));Application.Run(new frmAttandeance(engine));}catch (Exception ex){MessageBox.Show(string.Format("An error has occured: {0}", ex.Message), "Nffv C# Sample",

50

MessageBoxButtons.OK, MessageBoxIcon.Error);}finally{if (engine != null){engine.Dispose();}}

}}}

CHAPTER-5

5.CONCLUSION & REFERENCES:

5.1.CONCLUSION

The designed system provides an acknowledgement to the client whose attendance has been

taken and when. It also describes the total sum of attendance that is done by the client. There

is a lot of benefits of the system i.e. students attendance record to the parents on daily basis,

employee‟s attendance notification as they punch: reduces the overhead in the compilation of

attendance at the end of the month also the employee know that how much amount of salary

he will get as he/she knows the total duration of work done.

With the help of this proposed model, one can easily monitor data from any remote location

via SMS, there is no need of direct contact, internet or any kind of request send by user as it

is push based technique.

5.2.REFERENCES

Mohd Helmy Abd Wahab 2010 “Design and Development of Portable RFID for Attendance

System”, 978-1-4244-5651-2/10, 2010,

Qun Hou,, Wuhan, Hubei, 2010 “Research and Implementation of Remote Heart Rate

Monitoring System Based on GSM and MCU”, CHINA,

51

Yan Hongwei , Pan Hongxia, 2009 “Remote Data Monitoring System Design Based on GSM

Short Message Service” in IEEE International Symposium on Industrial Electronics (ISlE

2009) Seoul Olympic Parktel, Seoul, Korea. [4] T.S. Lim, S.C. Sim and M.M. Mansor, 2009

“RFID Based Attendance System”, 2009 IEEE Symposium on Industrial Electronics and

Applications (ISIEA 2009), Kuala Lumpur, Malaysia [5] Z. Yongqiang, L. Ji 2006 “The

Design of Wireless Fingerprint Attendance System” International Conference on

Communication Technology, ICCT '06, Handan, Hebei, China, 27-30 November 2006, pp. 1-

4.. M. Man, L.Y. Kyng 2007 “Utilizing MYKAD Touch N Go features for Student

Attendance System (TITO)”. Proceeding of 1st International Malaysian Educational

Technology Convention 2007, Johor Bahru, Malaysia, pp.114-120. [Sidi, Jonathan, N

Syahrul, Junaini, and Lau, S. Ling. 2007 ISAMS: Tracking Student Attendance using

Interactive Student Attendance management System. Third Malaysian Software Engineering

Conference (MySEC‟07), Selangor, Malaysia, pp. 1-5. H.J. vogel, C.Bettstetter and

C.Hartmann “GSM – Architecture, Protocols and Services”, Third Edition, John Wiley &

Sons, Ltd. ISBN: 978- 0- 470- 03070- 7

jong-Liang Wu, Wing W. Y. Ng, Daniel S. Yeung, Hai-Lan Ding, 2009 “A Brief Survey On

Current Rfid Applications” In proceeding of 8th International Conference on Machine

Learning and Cybernetics, Baoding. Cheng-Ming Jimmy and Li, Director, 2006 “An

Integrated Software Platform for RFID-Enabled Application Development” IEEE

International Conference on Sensor Networks, Ubiquitous, and Trustworthy Computing

(SUTC‟06) . Kuo-shien Huang, Shun-ming Tang, 2008 “RFID Applications Strategy and

Deployment in Bike Renting System” ICACT 2008, ISBN 978-89-5519-136-3 [Monzur

Kabir 2009 “GSM Network Architecture” Ph.D, Thesis. [LI Hai-lin LUO Chang-yuan

WANG Ya-di, 2008 “Design of Equipment Management Information System Based on

RFID”, F. Klaus. 2003 “RFID Handbook: Fundamentals and Applications in Contactless

52

Smart Cards and Identification”, Munich Germany, John Wiley & Sons, 2003. Jifeng Ding,

Jiyin Zhao，Biao Ma, 2009 “Remote monitoring system of temperature and humidity based

on GSM”, 978-1-4244-4131-0/09.

Cheng-Ming Jimmy Li, “An Integrated Software Platform for RFID-Enabled Application

Development”, Proceeding of the IEEE International Conference on Sensor Networks,

Ubiquitous, and Trustworthy Computing (SUTC‟06).

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