1.1 Introduction:

Chapter 1

Introduction to the Project

The term ‘RFID’ stands for Radio Frequency Identification. In recent years automatic identification procedures (Auto-ID) have become very popular in many service industries, purchasing and distribution logistics, industry, manufacturing companies and material flow systems. Automatic identification procedures exist to provide information about people, animals, goods and products in transit. The omnipresent barcode labels that triggered a revolution in identification systems some considerable time ago, are being found to be inadequate in an increasing number of cases. Barcodes may be extremely cheap, but their stumbling block is their low storage capacity and the fact that they cannot be reprogrammed. The technically optimal solution would be the storage of data in a silicon chip.

Radio Frequency Identification (RFID) is a generic term for non-contacting technologies that use radio waves to automatically identify people or objects. There are several methods of identification, but the most common is to store a unique serial number that identifies a person or object on a microchip that is attached to an antenna. The combined antenna and microchip are called an "RFID transponder" or "RFID tag" and work in combination with an "RFID reader" (sometimes called an "RFID interrogator").

1.2 Project overview:

In this project we describe the design, construction and operation of a digital voting machine using RFID system and a microcontroller profoundly.

Here, a RFID card is used for identification of a person before giving his vote by placing his RFID Card before the RFID Reader module. When the card is placed before the reader, the details stored with the unique number in the microcontroller will be checked and will be displayed. If he/she is eligible for voting, they’ll be sent to voting unit where they will be giving their vote to the any of the parties/candidates listed only once. If they try to violate any of the rules like giving their vote more than once or if he/she is not the eligible person, then an alarming Buzzer will be activated. And at last by pressing the result switch, the Candidate with maximum votes will be declared as winner or it’ll be displayed ‘Tie’.

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Chapter-2 Block Diagram and its Description

2.1 Basic block diagram:

The block diagram comprises of few major blocks as follows, • Power supply unit • Voting unit (RFID Module and Microcontroller) • Conformation Unit (LED/Buzzer) • Display unit (LCD)

Result

Figure 1 Block Diagram of EVM 2.2 Block diagram description:

2.2.1 Power supply unit:

Power supply is a very important part of electronic circuit this circuit required fixed +5 V supply so to fix this voltage we needed voltage regulator. In this work we used IC7805 Voltage regulator whose output is fixed at +5 volts. A voltage regulator generates a fixed output voltage of a preset magnitude that remains constant regardless of changes to its input voltage or load conditions. There are two types of voltage regulators: linear and switching. A linear regulator employs an active (BJT or MOSFET) pass device (series or shunt) controlled by a high gain differential amplifier. It compares the output voltage with a precise reference voltage and adjusts the pass device to maintain a constant output voltage.

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2.2.2 Voting unit:

It is a combination of two very major units o RFID Module o AT mega 16 micro controller.

2.2.2.1 RFID Reader Module and Card:

i) RFID Card:

The RFID card is the Identification card we will be using in this project. RFID systems are closely related to the smart cards. Like smart card systems, data is stored on an electronic data-carrying device --- the transponder. However, unlike the smart card, the power supply to the data-carrying device and thereade3r are achieved without the use of galvanic contacts, using instead magnetic or electromagnetic fields.

Figure 2 Typical architecture of a microprocessor card.

The underlying technical procedure is drawn from the fields of radio and radar engineering. Here, the information is carried by radio waves, Dye to the numerous advantages of RFID systems compared with other identification systems, RFID systems are now beginning to conquer new mass markets, and one example is the use of contactless smart cards as tickets for short-distance public transport.

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Figure 3 RFID Reader Module (#28140)

ii) RFID Reader module:

A RFID reader is the major section in identification process. It is simply called as reader module.

a) Components of a RFID system:

An RFID system is always made up of two components (Figure):

• The transponder, which is located on the object to be identified; • The interrogator or reader, which, depending upon the design and the technology used, may be a read or write/read device (in this book — in accordance with normal colloquial usage — the data capture device is always referred to as the reader, regardless of whether it can only read data or is also capable of writing). A

reader typically contains a radio frequency module (transmitter and receiver), a control unit and a coupling element to the transponder. In addition, many readers are fitted with an additional interface (RS 232, RS 485, etc.) to enable them to forward the data received to another system (PC, robot control system, etc.). The transponder, which represents the actual data-carrying device of an RFID system, normally consists of a coupling element and an electronic microchip.

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Figure 4: The reader and transponder are the main components of every RFID system

An RFID system consists of a reader and one or more tags. The reader's antenna

is used to transmit radio frequency (RF) energy. Depending on the tag type, the energy is "harvested" by the tag's antenna and used to power up the internal circuitry of the tag. The tag will then modulate the electromagnetic waves generated by the reader in order to transmit its data back to the reader. The reader receives the modulated waves and converts them into digital data. In the case of the Parallax RFID Reader Module, correctly received digital data is sent serially through the SOUT pin.

Figure 5 Flow of process of an RFID system

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The basic layout can be understood by the following diagram.

Figure 6: Basic layout of the RFID data-carrying device, the transponder. Left, inductively coupled transponder with antenna coil; right, microwave transponder with dipolar antenna

When the transponder, which does not usually possess its own voltage supply (battery), is not within the interrogation zone of a reader it is totally passive. The transponder is only activated when it is within the interrogation zone of a reader. The power required to activate the transponder is supplied to the transponder through the coupling unit (contactless), as are the timing pulse and data.

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iii) Switching Section:

It comprises of series of switches (We used Tactile switches) allocated for number of parties present. These switching section will be activated only when it receives conformation signal from the Micro controller. i.e., only a valid person with his/her valid RFID card will be able to give his vote.

Figure 7: Graphical Representation of Switching section.

Figure 8: Tactile switches used in switching section.

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Table 1: Comparison of different RFID systems showing their advantages and disadvantages.

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2.2.2.2 Communication Protocol:

Implementation and usage of the RFID Reader Module is straightforward. BASIC Stamp 1, 2, and SX28AC/DP code examples (SX/B) are included at the end of this documentation. The RFID Reader Module is controlled with a single TTL-level active-low /ENABLE

pin. When the /ENABLE pin is pulled LOW, the module will enter its active state and enable the antenna to interrogate for tags. The current consumption of the module will increase dramatically when the module is active. A visual indication of the state of the RFID Reader Module is given with the on-board LED. When the module is successfully powered-up and is in an idle state, the LED will be GREEN. When the module is in an active state and the antenna is transmitting, the LED will be RED. The face of the RFID tag should be held parallel to the front or back face of the antenna (where the majority of RF energy is focused). If the tag is held sideways (perpendicular to the antenna) you'll either get no reading or a poor reading. Only one transponder tag should be held up to the antenna at any time. The use of multiple tags at one time will cause tag collisions and confuse the reader. The two tags available in the Parallax store have a read distance of approximately 3 inches. Actual distance may vary slightly depending on the size of the transponder tag and environmental conditions of the application. When a valid RFID transponder tag is placed within range of the activated reader, the unique ID will be transmitted as a 12-byte ASCII string via the TTL-level SOUT (Serial Output) pin in the following format:

The start byte and stop byte are used to easily identify that a correct string has been received from the reader (they correspond to a line feed and carriage return characters, respectively). The middle ten bytes are the actual tag's unique ID.

All communication is 8 data bits, no parity, 1 stop bit, non-inverted, least significant bit first (8N1). The baud rate is configured for 2400bps, a standard communications speed supported by most any microprocessor or PC, and cannot be changed. The Parallax RFID Reader Module initiates all communication. The Parallax RFID Reader Module can connect directly to any TTL-compatible UART or to an RS232-compatible interface by using an external level shifter.

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2.2.3 Micro controller: • It is the heart of this project. We used At mega 16 micro controller (Atmel-medium-

16-KB of flash memory). • It is able to receive unique code from RFID module. Then it checks weather the code

is authorized or not by comparing the received code to already stored code. • If received code and stored code are matched, then it allows the voter to put his vote

to either of the parties. • It also displays voter name and weather he has finished giving his vote or not.

2.2.3.1 Pin configuration:

Figure 9: Pin configuration of ATmega 16 Micro Controller

Pin descriptions of ATmaga16L Microcontroller

VCC: Digital supply voltage. GND: Ground.

Port B (PB7...PB0):

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

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a reset condition becomes active, even if the clock is not running. Port B also serves the unction’s of various special features of the ATmega16. Port C (PC7...PC0):

Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port C output buffers have symmetrical drive characteristics with both high sink and 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. If the JTAG interface is enabled, the pull-up resistors on pins PC5 (TDI), PC3 (TMS) and PC2 (TCK) will be activated even if a reset occurs. Port C also serves the functions of the JTAG interface and other special features of the ATmega16.

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 symmetrical drive characteristics with both high sink and source capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up resistors are activated. The Port D pins are tri-stated when a reset condition becomes active, even if the clock is not running. Port D also serves the functions of various special features of the ATmega16.

Port A (PA7...PA0):

Port A serves as the analog inputs to the A/D Converter. Port A also serves as an 8-bit bi-directional I/O port, if the A/D Converter is not used. Port pins can provide internal pull-up resistors (selected for each bit). The Port A output buffers have symmetrical drive characteristics with both high sink and source capability. When pins PA0 to PA7 are used as inputs and are externally pulled low, they will source current if the internal pull-up resistors are activated. The Port A pins are tri-stated when a reset condition becomes active, even if the clock is not running.

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. Shorter pulses are not guaranteed to generate a reset.

AVCC:

AVCC is the supply voltage pin for Port A and the A/D Converter. It should be externally connected to VCC, even if the ADC is not used. If the ADC is used, it should be connected to VCC through a low-pass filter.

AREF:

AREF is the analog reference pin for the A/D Converter.

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XTAL1:-

Input to the inverting Oscillator amplifier and input to the internal clock

operating circuit.

XTAL2:-

Output from the inverting Oscillator amplifier.

2.2.4 Conformation unit

From this unit we are able to know that the voter has voted his vote

or not. If the vote is successful a buzzer is beeped. And if the voter is a valid

voter and if he tries to come again the second time after giving his vote, there

will be a long buzzing sound(for 5 sec) from the buzzer. If the voter is not at

all a valid voter then the buzzer will be on for 3 sec. Here we used a 12V

Buzzer shown in the below figure.

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2.2.5 Display unit:

• For display purpose we use a 20x4 lcd display. • It can display 80 characters. • It is able to display Alpha Numeric Characters.

Figure 12: Pin configuration of a 20x4 LCD

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Chapter-3

Working and Schematic Diagram

3.1 Working of the circuit:

The high level electronic voting machine built with ATmega16 Micro controller. The micro controller port D uses for LCD display and port C.0 (pin 22) uses for voting power or presiding officers button. The candidate button input from Port C.1 – C.4 (pin 23 to 26; 4 candidate). The output LED and buzzer uses Micro controller port C.5 and C.6. The LCD backlight also connected to port C.7 via a transistor. At the starting of voting the election commission offices setup the machine at the center. Then power on the switch and sealed it that nobody can power off. The presiding officer identifies the original voter of that particular area and pushes the voting power button. The voting power LED glow then and continues until once press the candidate buttons. The voter then goes to the secret room where Voting unit placed and press button beside his candidate symbol. Voter can watch success of voting by glowing confirmation LED and beep indication. The presiding officer can also hear beep sound watch a confirmation LED. Same time the voting power goes down and nobody can vote again. Mainly when presiding officer press voting power button, Micro controller start scanning from pin 23 to pin 26. When get response from a specific pin, increase the counter one of that candidate and stop scanning. So it is not possible to voting twice or more. All the counter result store at Micro controller EEPROM. When the voting is under process it will showed at display “Voting under Process”.

At the end of voting we need to know result. Then election commission or

presiding officer presses the secret key (password). Now the Micro controller shows the result and supply the power to LCD backlight that it illuminated. If it needs to return voting process again one should press another secret key. There uses a transistor to operate buzzer and confirmation LED with proper current. There also uses a voltage regulator (7805) to supply 5v continuously. Here uses a dry cell 9V battery as power source. The power consumption of the system is very low (50mW- 150mW varying). After collected data and need erase recorded data from EEPROM just broken the sealed on power button and power off the system. Now the system is ready for next election.

The voter is allowed to give his vote to only one party only once by pressing

any one of the switch from the switching section.

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3.2 Schematic Diagram: Figure 13: Schematic Diagram.

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3.3 Printed Circuit Board:

The micro controller and other components are soldered on to a PCB. The PCB (printed circuit board) is shown below.

A printed circuit board, or PCB, is used to mechanically support and

electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non- conductive substrate. It is also referred to as printed wiring board (PWB) or etched wiring board. A PCB populated with electronic components is a printed circuit assembly (PCA), also known as a printed circuit board assembly (PCBA). Printed circuit boards are used in virtually all but the simplest commercially produced electronic devices. PCBs are inexpensive, and can be highly reliable. They require much more layout effort and higher initial cost than either wire wrap or point-to-point construction, but are much cheaper and faster for high-volume production; the production and soldering of PCBs can be done by automated equipment. Much of the electronics industry's PCB design, assembly, and quality control needs are set by standards that are published by the IPC organization.

Figure14: PCB layout

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Chapter-4 Hardware Design & Descriptions

4.1 Procedure Followed While Designing:

• Then we programmed the microcontroller using sinaprog software using hex

file.

• Then soldering process was done. After completion of the soldering process

we tested the circuit.

• Still the desired output was not obtained and so troubleshooting was done. In

the process of troubleshooting we found the circuit aptly soldered and

connected and hence came to conclusion that there was error in programming

section which was later rectified and the desired results were obtained.

4.2 List of Components:

Following are the list of components that are used to build the assembly of the

power supply unit, voting unit, display unit and for buzzer.

i) Micro controller Atmega16

ii) RFID module

iii) RFID cards

iv) Max 232 IC

v) 8 MHz crystal

vi) SL100 transistor

vii) IC7805 (Regulator)

viii) 230 to 12 Volts AC step-down transformer

ix) Resistors

x) Capacitors

xi) LED

xii) LCD

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I) Micro controller Atmega16:

Refer to Pg. No: 10

II) RFID module: Refer to Pg. No: 04

III) RFID cards:

Refer to Pg. No: 03

IV) MAX232 IC:

It is used to convertsignals 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.

Figure 15: Max232 IC 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.

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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.

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.

V) SL100 Transistor: SL100 is a general purpose, medium power NPN transistor. It is mostly

used as switch in common emitter configuration. The transistor terminals require a fixed DC voltage to operate in the desired region of its characteristic curves. This is known as the biasing. For switching applications, SL100 is biased in such a way that it remains fully on if there is a signal at its base. In the absence of base signal, it gets turned off completely. The emitter leg of SL100 is indicated by a protruding edge in the transistor case. The base is nearest to the emitter while collector lies at other extreme of the casing.

Figure 16: SL100 Transistor

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VI) Crystal Oscillator:

A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency. This frequency is commonly used to keep track of time (as in quartz wrist watches), to provide a stable clock signal for digital integrated circuits, and to stabilize frequencies for radio transmitters and receivers. The most common type of piezoelectric resonator used is the quartz crystal, so oscillator circuits incorporating them became known as crystal oscillators, but other piezoelectric materials including polycrystalline ceramics are used in similar circuits.

Figure 17: 8 MHz Crystal

VII) IC7805 (Regulator):

Voltage regulator ICs is available with fixed (typically 5, 12 and 15V) or

variable output voltages. The maximum current they can pass also rates them. Negative

voltage regulators are available, mainly for use in dual supplies. Most regulators include

some automatic protection from excessive current ('overload protection') and

overheating ('thermal protection'). Many of the fixed voltage regulators ICs have 3

leads and look like power transistors, such as the 7805 +5V 1A regulator shown on the

right. The LM7805 is simple to use. You simply connect the positive lead of your

unregulated DC power supply (anything from 9VDC to 24VDC) to the Input pin,

connect the negative lead to the Common pin and then when you turn on the power,

you get a 5 volt supply from the output pin.

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78XX:-

Figure 18: IC 7805

The Bay Linear LM78XX is integrated linear positive regulator with three

terminals. The LM78XX offer several fixed output voltages making them useful in wide

range of applications. When used as a zener diode/resistor combination replacement,

the LM78XX usually results in an effective output impedance improvement of two

orders of magnitude, lower quiescent current. The LM78XX is available in the TO-252,

TO-220 & TO-263packages,

Features:-

Output Current of 1.5A

Output Voltage Tolerance of 5%

Internal thermal overload protection

Internal Short-Circuit Limited

Output Voltage 5.0V, 6V, 8V, 9V, 10V, 12V, 15V, 18V, 24V. Regulated Power Supply:

The power supplies are designed to convert high voltage AC mains electricity to

a suitable low voltage supply for electronic circuits and other devices. A RPS

(Regulated Power Supply) is the Power Supply with Rectification, Filtering and

Regulation being done on the AC mains to get a Regulated power supply for

Microcontroller and for the other devices being interfaced to it.

A power supply can by broken down into a series of blocks, each of which performs a

particular function. A DC power supply which maintains the output voltage constant

irrespective of AC mains fluctuations or load variations is known as “Regulated D.C

Power Supply”

For example a 5V regulated power supply system as shown in the next page.

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Figure 19: Components of a typical linear power supply

VIII) Transformer:

A transformer is an electrical device which is used to convert electrical power

from one Electrical circuit to another without change in frequency.

Transformers convert AC electricity from one voltage to another with little loss

of power. Transformers work only with AC and this is one of the reasons why mains

electricity is AC. Step-up transformers increase in output voltage, step-down

transformers decrease in output voltage. Most power supplies use a step-down

transformer to reduce the dangerously high mains voltage to a safer low voltage. The

input coil is called the primary and the output coil is called the secondary. There is no

electrical connection between other two coils; instead they are linked by an alternating

magnetic field created in the soft-iron core of the transformer. The two lines in the

middle of the circuit symbol represent the core. Transformers waste very little power

so the power out is (almost) equal to the power in. Note that as voltage is stepped down

current is stepped up. The ratio of the number of turns on each coil, called the turn’s

ratio, determines the ratio of the voltages. A step-down transformer has a large number

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of turns on its primary (input) coil which is connected to the high voltage mains supply,

and a small number of turns on its secondary (output) coil to give a low output voltage.

Figure 20: 230 AC to 9V AC Step down transformer.

Turns ratio = Vp/ VS = Np/NS.

Power Out= Power In VS X IS=VP X IP

Vp = primary (input) voltage

Np = number of turns on primary coil

Ip = primary (input) current

IX) Resistors:

A resistor is a device which opposes current in a dc (direct current) circuit; a

measure of this opposition is called resistance, measured in ohms…. Ohm’s Law, the

relationship between voltage, current, and resistance, states that current is directly

proportional to voltage and inversely proportional to resistance in a circuit.

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Figure 21: Resistors Generally for microcontroller for port P0 whatever we give the input it may be either 1

or 0 the output will be 0 itself because the port P0 will be internally connected to the

ground in order to eliminate this we connect Pull-up resistors in order to overcome

this now in this they are initially connected to the Vcc so that what the input will be the

same will be the output.

X) Capacitors:

Capacitors are in our project for Power Supply, when the AC voltage is initially

given to the bridge circuit in order to convert the AC to DC voltage. As soon as it gets

converted to DC voltage we will not get the pure DC because there will be spikes of

AC voltage. In order to reduce this, we use 1000uf/25v, again we will use the 10uf in

order to reduce the noise that is generated in circuit i.e. thermal noise.

We have seen that the ripple content in the rectified output of half wave rectifier is

121% or that of full-wave or bridge rectifier or bridge rectifier is 48% such high

percentages of ripples is not acceptable for most of the applications. Ripples can be

removed by one of the following methods of filtering.

Figure 22: Capacitor

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(a) A capacitor, in parallel to the load, provides an easier by –pass for the ripples

voltage though it due to low impedance. At ripple frequency and leave the D.C. to

appear at the load.

(b) An inductor, in series with the load, prevents the passage of the ripple current (due

to high impedance at ripple frequency) while allowing the DC (due to low resistance to

DC)

(c) Various combinations of capacitor and inductor, such as L-section filter section

filter, multiple section filter etc. which make use of both the properties mentioned in

(a) and (b) above. Two cases of capacitor filter, one applied on half wave rectifier and

another with full wave rectifier.

Filtering is performed by a large value electrolytic capacitor connected across the

DC supply to act as a reservoir, supplying current to the output when the varying DC

voltage from the rectifier is falling. The capacitor charges quickly near the peak of the

varying DC, and then discharges as it supplies current to the output. Filtering

significantly increases the average DC voltage to almost the peak value (1.4 × RMS

value).

To calculate the value of capacitor(C),

C = ¼*√3*f*r*Rl

Where,

f = supply frequency,

r = ripple factor,

Rl = load resistance

Note: In our circuit we are using 1000µF hence large value of capacitor is placed to

reduce ripples and to improve the DC component.

XI) LED:-

The light emitting diode (LED) is commonly used as an indicator. It can show

when the power is on, act as a warning indicator, or be part of trendy jewelry etc. It

needs to be fed from a DC supply, with the anode positive and the cathode negative, as

shown in the diagram.

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To calculate the value of the series resistor we need to know the diode forward

voltage and current and its connections. The necessary data can be obtained from a

catalogue or data book. In our example it is 2 volts and 20mA (0.02 amps). The

cathode lead is the one nearest a "flat" on the body. Since the voltage across the diode

is 2 volts and the battery voltage is 12 volts, then the voltage across the resistors 12-2

= 10 volts. The diode is in series with the resistor, so the current through then both is

the same, 0.02 amps.

We now know the voltage across, and the current through the resistor. From Ohm's Law

we can now calculate the value of the resistor.

Resistance = Volts divided by Amps = V/I = 10/0.02 =500 ohms. Since this is not a standard value we can use a 470 or 560 ohm resistor as this application

is not.

xiii) Liquid Crystal Display (LCD):-

An LCD consists of two glass panels, with the liquid crystal material sand witched

in between them. The inner surface of the glass plates are coated with transparent

electrodes which define the character, symbols or patterns to be displayed polymeric

layers are present in between the electrodes and the liquid crystal, which makes the

liquid crystal molecules to maintain a defined orientation angle.

One each polarizers are pasted outside the two glass panels. These polarizers would

rotate the light rays passing through them to a definite angle, in a particular direction

When the LCD is in the off state, light rays are rotated by the two polarizers and

the liquid crystal, such that the light rays come out of the LCD without any orientation,

and hence the LCD appears transparent. When sufficient voltage is applied to the

electrodes, the liquid crystal molecules would be aligned in a specific direction. The

light rays passing through the LCD would be rotated by the polarizers, which would

result in activating / highlighting the desired characters.

The LCD’s are lightweight with only a few millimeters thickness. Since the LCD’s

consume less power, they are compatible with low power electronic circuits, and can

be powered for long durations.

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The LCD’s don’t generate light and so light is needed to read the display. By using

backlighting, reading is possible in the dark. The LCD’s have long life and a wide

operating temperature range. Changing the display size or the layout size is relatively

simple which makes the LCD’s more customer friendly.

Figure 23: A 20x4 LCD

The LCD display consists of two lines, 20 characters per line that is interfaced

with the PIC16F73.The protocol (handshaking) for the display is as shown in Fig. The

display contains two internal byte-wide registers, one for commands (RS=0) and the

second for characters to be displayed (RS=1). It also contains a user-programmed RAM

area (the character RAM) that can be programmed to generate any desired character

that can be formed using a dot matrix. To distinguish between these two data areas, the

hex command byte 80 will be used to signify that the display RAM address 00h will be

chosen Port1 is used to furnish the command or data type, and ports 3.2 to 3.4 furnish

register select and read/write levels.

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Chapter 5 Software Design

Another important section in this project is the program code. It can’t be

possible without writing a code to interface all the major components like Micro controller, RFID cards and LCD.

The flow chart for easy understanding is given below. 5.1 Flow chart:

Start

Micro Controller Initialize

Entered Person

Invalid User

Return for next vote

Valid user

Permitted to give his vote

Initiate buzzzer

Yes Security key

for Result

Yes Show Result in the display

Reset key for fresh voting

End

Figure 24: Flow chart of Electronic voting using RFID

5.2 Program code:

#include <mega16.h> #include <string.h> #include"lcd.h"

unsigned char temp=0; unsigned char recv_buf[30]; unsigned int rx_flag = 0; unsigned char index=0,key_ok=0;

void main(void) {

unsigned char TDP=0,LOK=0,BJP=0,CPI=0; unsigned char r=0,v=0,a=0,b=0; char *p1="6B0037F2F45A"; char *p2="6B0037FAC563"; char *p3="6B0037EC71C1"; char *p4="6B0037CB65F2";

init_display(); clear_display();

disp_cstr(0,0," ELECTRONIC VOTING "); disp_cstr(1,0," MACHINE USING RFID"); disp_cstr(2,0," "); disp_cstr(3,0," "); delay_ms(5000); disp_cstr(0,0,"RFID VOTING MACHINE "); disp_cstr(1,0," PUT YOUR CARD ");

while (1) {

if(rx_flag==1) {

rx_flag=0; if(!strcmp(recv_buf,p1))

{

disp_cstr(1,0," P.VIJAY KUMAR "); v++; if(v>1) { disp_cstr(1,0," DO NOT CHEAT "); PORTB.0=1; delay_ms(2000); PORTB.0=0; key_ok=0;

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disp_cstr(1,0," PUT YOUR CARD "); } else key_ok=1;

} else if(!strcmp(recv_buf,p2)) {

disp_cstr(1,0," A.ARUN KUMAR "); a++;

if(a>1) { disp_cstr(1,0," DO NOT CHEAT "); PORTB.0=1; delay_ms(2000); PORTB.0=0; key_ok=0; disp_cstr(1,0," PUT YOUR CARD ");

} else key_ok=1;

} else if(!strcmp(recv_buf,p3)) {

disp_cstr(1,0," RAJASHEKAR REDDY "); r++;

if(r>1) {

disp_cstr(1,0," DO NOT CHEAT "); PORTB.0=1; delay_ms(2000); PORTB.0=0; key_ok=0; disp_cstr(1,0," PUT YOUR CARD ");

} else key_ok=1;

} else if(!strcmp(recv_buf,p4)) {

disp_cstr(1,0," CH.BHARATH NAIDU "); b++;

if(b>1) { disp_cstr(1,0," DO NOT CHEAT "); PORTB.0=1; delay_ms(2000); PORTB.0=0; key_ok=1;

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disp_cstr(1,0," PUT YOUR CARD "); } else key_ok=1;

} else { key_ok=0; disp_cstr(1,0," U R NOT AUTHORISED"); PORTB.0=1; delay_ms(5000); disp_cstr(1,0," PUT YOUR CARD "); PORTB.0=0; }

while(key_ok) { if(!PINA.0)

{ delay_ms(500); while(!PINA.0); TDP++; key_ok=0; disp_cstr(1,0," PUT YOUR CARD ");

} else if(!PINA.1)

{ delay_ms(500); while(!PINA.1); BJP++; key_ok=0; disp_cstr(1,0," PUT YOUR CARD "); }

else if(!PINA.2) { delay_ms(500); while(!PINA.2); LOK++; key_ok=0; disp_cstr(1,0," PUT YOUR CARD ");

} else if(!PINA.3)

{ delay_ms(500); while(!PINA.3); CPI++; key_ok=0; disp_cstr(1,0," PUT YOUR CARD "); }

} }

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if(!PINA.4) {

disp_cstr(0,0,"TDP= BJP= "); disp_cstr(1,0,"LOK= CPI= "); set_LCD_cur(0,4); if(TDP==0) wr_disp('0'); else send_math(TDP); set_LCD_cur(0,14); if(BJP==0) wr_disp('0'); else send_math(BJP); set_LCD_cur(1,4); if(LOK==0) wr_disp('0'); else send_math(LOK); set_LCD_cur(1,14); if(CPI==0) wr_disp('0'); else send_math(CPI); delay_ms(5000); disp_cstr(0,0," "); if(TDP>BJP&&TDP>LOK&&TDP>CPI) disp_cstr(1,0," TDP HAS WON "); else if(BJP>TDP&&BJP>LOK&&BJP>CPI) disp_cstr(1,0," BJP HAS WON "); else if(LOK>BJP&&LOK>TDP&&LOK>CPI) disp_cstr(1,0," LOKSATHA HAS WON "); else if(CPI>BJP&&CPI>LOK&&CPI>TDP) disp_cstr(1,0," CPI HAS WON "); else disp_cstr(1,0," TIE ");

} }

}

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Chapter 6 Testing and Results

Result Analysis:

We started our project by making power supply. That is easy for me but when

we turn toward the main circuit, there are many problems and issues related to it, which

are we faced, like component selection, which components is better than other and its

feature and cost wise also, then refer the data books and other materials related to its.

We had issues with better or correct result, which we desired. And also the software

problem.

We also had some soldering issues which were resolved using continuity

checks performed on the hardware

We started testing the circuit from the power supply. There we got over first

trouble. After getting 9V from the transformer it was not converted to 5V and the circuit

received 9V.

As the solder was shorted IC 7805 got burnt. So we replaced the

IC7805.also the circuit part around the IC7805 were completely damaged with the help

of the solder we made the necessary paths.

It would be a problem to identify individual RFID cards unless it is placed

before the RFID reader module and LCD is a must in this process.

It will be helpful for small elections like electing a class representative or for

any situation to vote for few choices among few members.

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Evolution

Applications:

o It can be used in taking group decisions where voting is confidential. o It can be used in companies, industries, Schools, Colleges or any Private

or Government Sectors.

o It can be used for different purposes not only for voting system.

Advantages:

o Tampering is not possible. o Good security can be achieved by using this technology. o Process for voting would be very easy.

Disadvantages:

o If Micro controller is damaged, then it’ll be difficult to re install, program and solder the part.

o There must be scrutiny of the persons because RFID card is transferable and there can be a chance for a person to come with other person’s card.

o Extreme care must be taken to protect the entire circuit/PCB from getting damaged.

Future scope: o A timer could be included, which could automatically end the voting

after specified duration of time.

o Biometric verification of voters, so that automatically it can be insured that one person is voting only once.

o It can be made more interactive by adding sound effect (speech) to it. o EEPROM can be used to store the data permanently. o If we make more than one EVM, each to be used at all different

locations and the final result is the addition of result of all, we could

think of connecting them to communicate with each other and final

result can be shown on one of the LCD.

o Touch can be implemented in place of switches.

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Conclusion

With the knowledge in Electronics we could make an application like “Electronic

voting machine using RFID” Our project installation is somewhat difficult but once

installed it is easy to work with it. The circuit can easily connect to the output port of

LCD and can be used to see which person is going to the voting machine.

We completed our mini project with desired output. The desired output was

obtained by a microcontroller which is followed by RFID Module. The circuit was

analyzed and verified with different inputs successfully.

Final apparatus of our project

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Bibliography [1] International Journal of Information and Electronics Engineering, Vol. 3, No. 2,

March 2013. [2] E. Proebstel, S. Riddle, F. Hsu, J. Cummins, F. Oakley, T. Stanionis, and M. Bishop, “An Analysis of the Hart Intercivic DAU eSlate,” in Proc. Of Usenix/Accurate Electronic Voting Technology Workshop, 2007.

[3] For Data Sheet of Micro controller,

http://www.atmel.com/Images/doc2466.pdf

[4] klaus Finkenzeller, ‘RFID Handbook for Fundamentals and Applications in contactless Smart Cards, Radio Frequency identification and Near-Field Communication’ 3rd Edition, [WILEY].

[5] For RFID Reader module (328140),

PARALLAX, Inc. www.parallax.com

[6] For most of the images and information,

www.google.com

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