Electronic Lock Code System

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ELECTRONIC CODE LOCK

TRAINING REPORTOF

SIX WEEKS INDUSTRIAL TRAINING, UNDERTAKEN

AT

DOEACC Society,Chandigarh

ON


SUBMITTED IN PARTIAL FULFILLMENT OF THE

DEGREE(B.E. - Electronics and Communication - 2009)

Under the Guidance of Submitted By:-Name: Mr. Sarwan Singh Manvinder Saini

B090020213Department: Embedded Systems Tushar MittalB090020529

Sushant choudharyB090020359

Chitkara University, Himachal Pradesh


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Vinay SharmaB090020378

Shikhil VyasB090020328

As the part of B.E (ECE), we have undergone six weeks industrial training, after our 7 th trimester, from

DOEACC Society, Chandigarh, as it is growing organization in the field of embedded system. In this

training, we explored our knowledge related to the electronics. During this period we worked on the project

LCD DISPLAY USING MICROCONTROLLER 8051 which is basis of INTERFACING OF LCD

WITH MICROCONTROLLER.

Areas covered under Hardware section:

Basic introduction to various electronic components.

Soldering and Desoldering practices.

Positive regulated power supplies.

LCD interfacing with microcontroller

Areas covered under Software section:

Introduction to 8051 Microcontroller.

Programming of basic 8051 instructions such as data flow instructions, jump

and branching instructions, arithmetic and logical instructions etc.

Programming for interfacing of 8051 with LCD.

Project work:



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In this 6 week industrial training, the project assigned to us was LCD DISPLAY USING

MICROCONTROLLER 8051

The interface was implemented using the Atmels AT89C51microcontroller.

TABLE OF CONTENTS

1) Acknowledgement

2) Company Profile

3) Training Report

a) Introduction of Embedded System

i)Microprocessor

ii)Microcontrolller

b) Component Desciption

4) Project Report

a) Component list

b) Circuit Diagram

c) Circuit Description

d) Microcontroller8051

i) Pin description

ii) LCD

iii) Interfacing LCD with microcontroller

iv) Concept of programming

e) Soldering and desoldering

d) Conclusion5) Bibliography

a) Reference



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ACKNOWLEDGEMENT

Technology is like an ocean & engineer is like a pearl driver in search of a treasure beneath the sea. Today

technology is very vast and there is no end of technical studies. We are submitting our report on the project

entitled ELECTRONIC CODE LOCK.

We are very thankful to all the persons who with their views and participation helped us to carry this project

and report successfully. It is with pleasure that we find our selves penning down these lines to express my

sincere thanks to various people to help me along the way in completing the project.

With deep sense of gratitude, we express our sincere thanks to Mr.Kamal Jot Kansal, Mr.Sachin and

Mr.Pushpreet Singh for their precious guidance and for taking extra pain to seek through our problems. Under

their efficient guidance, we had no problem in acquiring and getting various jobs done. They were always a

pillar of strength to infuse encouragement during our disheartening failures.

We are greatly thnkful to Lt.Col.N.S.Julka {retd.} for providing us with this wonderful opportunity.



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DOEACC SocietySC0 114-116, Sector 17 B,

Chandigrah-160017

Website:-http://rcc.nic.in

Contact No. : - 0172-2703281, 2702263

COMPANY PROFILE

K.K. Technology is an organization which is established in the field of Network Support,

Network training, Embedded systems and VLSI-VHDL. We provide Support and training in the

field of Networking solutions, Programming Languages, Embedded systems (Micro

controller based design, Electronics system design) and VLSI-VHDL.K.K. Technology also

conducts courses in CADENCE based design tools.K.K. Technology also provides Technical

Research & Development support and consultancy to some Electronics companies.

Our clients for R&D support in field of embedded systems.

1) Recorders and Medicare ltd Chandigarh.

2) TELEBOX India ltd.

3) Lotus Machines Pvt. Ltd. Chandigarh.

4) Impearl Electronis Pvt. Ltd. Chandigarh.

5) KANTA Electrical Ltd. Mohali.

The partial list of our clientele for network field is as below:

1) CEDTI, Mohali2) Premier ISP, Chandigarh3) Innovative Solutions, Chandigarh4) Emmtel ISP, Chandigarh

http://rcc.nic.in/http://rcc.nic.in/


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5) NIPER, Mohali6) Navik Technologies, Chandigarh7) Software Technology Parks India, Mohali8) Glide Internet Services

9) Rana Group10) IDS11) HFCL Infotel Ltd. mohali12) Targus technologies pvt ltd13) STPI, Mohali14) BBMB15) The Tribune16) Quark17) Ind Swift18) Sagitech, Panchkula19) Jarc Infotech, Mohali

OUR TEAM

Presently we have a strong technical team of certified professionals for catering to these

solutions and have presence in Chandigarh and Punjab. We have skilled team of engineers who

are experienced in design, programming. We are having more than 10 engineers who are

working on latest technologies like VLSI-VHDL, Embedded, and Networking etc.

1) Er. Kamal Jot Kansal

M.Tech in ECE,B.Tech in E&I,4 year industrial experience on VLSI-VHDL

2) Er. Seema

Phd. PursuingMCA in 1st division4 year industrial experience on PHPSoftware Program Development Head

3) Er. Nipun Sharma

Phd. Pursuing in ECEMCA in 1st division



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B.Tech & CISCO Certified6 year industrial experience on NetworkingHead of Networking Department

COURSES Offered:-

For CSE/IT Branch:-

Software/ Programming Courses:-1) C/C++

2) Web Development (PHP) with Live Project

3) ASP.Net, VB.Net, C#.Net

4) JAVA ( Core JAVA, JAVA, ADVANCE JAVA, J2EE)

5) Oracle

6) Linux

7) MySQL, SQL

(b) Networking Courses

1) MCSE

2) CCNA

3) RHCE

For Electronics & Communication:-

1) VLSI-VHDL with Live Project

2) Embedded System Design with Live Project

3) Microcontroller with Live Project



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4) Microprocessor with Live Project

5) PCB Designing

Support Area (network solutions)

a) LINUX / UNIX networks

b) SUN networks

c) CISCO devices (Routers, Switches, Firewalls, Cache Engine, RAS etc)

d) Security Solutions

Design Services (Embedded systems)

a) AVR familyb) ELECTRONIC SYSTEM DESIGN

c) Pcb and layout designing

d) PIC family

e) Project development with ARM processors

f) Switch mode power supply design

Network Training

a) CISCO CCNA, CCNP

b) RED HAT LINUX

c) SUN SOLARIS

d) WINDOWS 2000, 2003

Our core strength is our commitment, technical expertise and cost effective solutions. We ensure

high service levels and prompt support availability leading to lower downtime.K.K. Technology is

a leader in education services and developer of innovative embedded solutions. To meet the

demands of Post PC era K.K. provides complete solutions as well as design-to-order services to

satisfy our customers.



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For K.K. Technology

Kamal Jot Kansal

TRAINING REPORT



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INTRODUCTION OF EMBEDDED SYSTEM

Now a days electronics have developed at very fast rate. It plays a major role in the life of human beingand makes it very easy and comfortable. Electronics circuits are designed to obtain a particular function.

For this purpose a no of electronic component are suitably connected.Embedded systems have proved

changing face of today's industrial scenario. An embedded system is a system is a special-

purpose computersystem designed to perform one or a few dedicated functions often with real-time

computing constraints. It is usually embedded as part of a complete device including hardware and

mechanical parts. In contrast, a general-purpose computer, such as apersonal computer, can do many

different tasks depending on programming.

Embedded systems control many of the common devices in use today. Fuelling in unbridled power into

industrial computers to tackle the most complex applications, they have made quite an impression with a

lot of the leading industrial sectors. Backed with the most durable components and peripherals sticking to

the highest quality standards, the next generation embedded computers have what it takes to endure highly

trying and harsh work environments. Multifunctional ability is the highlight of these systems even as they

comprise a uniquely designed combination of software and hardware to perform highly challenging tasks

that are a far cry for the common personal computers. This combination happens to be a programmed

platform that is assigned with specific applications for the task and goes through various tests to make

sure the systems offer long-life performance.

Embedded systems range from portable devices such as digital watches and MP3 players, to

large stationary installations like traffic lights, factory controllers, or be a crucial contributor systems

controlling nuclear power plants. Complexity varies from low, with a single microcontroller chip, to very

high with multiple units, peripherals and networks mounted inside a large chassis or enclosure. Embedded

computers serve their purpose in a variety of areas, like the gaming industry, military, security and

surveillance, and infotainment. Talking of their abilities and efficiency, a look into the highly popular

CorBrick855E embedded computer will offer a good insight into what is possible at their behest.

http://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Real-time_computinghttp://en.wikipedia.org/wiki/Real-time_computinghttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Real-time_computinghttp://en.wikipedia.org/wiki/Real-time_computinghttp://en.wikipedia.org/wiki/Personal_computer


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EXAMPLES OF EMBEDDED SYSTEM

Automated tiller machines (ATMS).

Cellular telephones and telephonic switches.

Computer network equipment, including routers timeservers and firewalls

Computer printers, Copiers.

Disk drives (floppy disk drive and hard disk drive)

Engine controllers and antilock brake controllers for automobiles.

Home automation products like thermostat, air conditioners sprinkles and

security monitoring system.

House hold appliances including microwave ovens, washing machines, TV

sets DVD players/recorders.

Medical equipment.

Measurement equipment such as digital storage oscilloscopes, logic

analyzers and spectrum analyzers.

Multimedia appliances: internet radio receivers, TV set top boxes.

Stationary video game controllers.



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MICROPROCESSOR

A microprocessor is a general-purpose digital computer central

processing unit (CPU). Although popularly known as a computer on a chip is

in no sense a complete digital computer. The block diagram of a microprocessor

CPU is shown, which contains an arithmetic and logical unit (ALU), a

program counter (PC), a stack pointer (SP),some working registers, a clock

timing circuit, and interrupt circuits.

FIG:BLOCK DIAGRAM OF A MICROPROCESSOR

MICROCONTROLLERS (MCU)

Figure shows the block diagram of a typical microcontroller, which is a

true computer on a chip. The design incorporates all of the features found in

micro-processor CPU, ALU, PC, SP, and registers. It also added the other

features needed to make a complete computer: ROM, RAM, parallel I/O,serial

I/O, counters, and clock circuit.


CPU RAM ROM I/O Port TimerSerial

COM

Port

Data Bus


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COMPARISON BETWEEN MICROPROCESSORS &

MICROCONTROLLERS

The microprocessor must have many additional parts to be operational as a

computer whereas microcontroller requires no additional external digital parts.

The prime use of microprocessor is to read data, perform extensive

calculations on that data and store them in the mass storage device or display

it. The prime functions of microcontroller is to read data, perform limited

calculations on it, control its environment based on these data. Thus themicroprocessor is said to be general-purpose digital computers whereas the

microcontroller are intend to be special purpose digital controller.

Microprocessor is concerned with the rapid movement of the code and

data from the external addresses to the chip, microcontroller is concerned with

the rapid movement of the bits within the chip.

Lastly, the microprocessor design accomplishes the goal of flexibility in the

hardware configuration by enabling large amounts of memory and I/O that

could be connected to the address and data pins on the IC package. The


RAM ROM

I/O Port TimerSerial

COM

Port

CPU

A single chip


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microcontroller design uses much more limited set of single and double byte

instructions to move code and data from internal memory to ALU.

COMPONENTS DESCRIPTION

RESISTOR

The resistor's function is to reduce the flow of electric current.This symbol

is used to indicate a resistor in a circuit diagram, known as a schematic.

Resistance value is designated in units called the "Ohm." A 1000 Ohm resistor is

typically shown as 1K-Ohm (kilo Ohm), and 1000 K-Ohms is written as 1M-

Ohm (megohm).There are two types of resistors;

1) Fixed resistors

2) Variable resistors.

They are also classified according to the material from which they are made.

The typical resistor is made of either carbon film or metal film. There are other

types as well, but these are the most common. The resistance value of the

resistor is not the only thing to consider when selecting a resistor for use in a

circuit. The "tolerance" and the electric power ratings of the resistor are also

important.



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The tolerance of a resistor denotes how close it is to the actual rated resistance

value. For example, a 5% tolerance would indicate a resistor that is within

5% of the specified resistance value. The power rating indicates how much

power the resistor can safely tolerate. The maximum rated power of the resistor

is specified in Watts. Power is calculated using the square of the current (I2) x

the resistance value (R) of the resistor. If the maximum rating of the resistor is

exceeded, it will become extremely hot and even burn.Resistors in electronic

circuits are typically rated 1/8W, 1/4W, and 1/2W. 1/8W.

Variable Resistors

There are two general ways in which variable resistors are used. One is the

variable resistor which value is easily changed, like the volume adjustment of

Radio. The other is semi-fixed resistor that is not meant to be adjusted by

anyone but a technician. It is used to adjust the operating condition of the circuit

by the technician. Semi-fixed resistors are used to compensate for the

inaccuracies of the resistors, and to fine-tune a circuit. The rotation angle of the

variable resistor is usually about 300 degrees. Some variable resistors must be

turned many times to use the whole range of resistance they offer. This allows

for very precise adjustments of their value. These are called "Potentiometers" or"Trimmer Potentiometers. In the photograph to the left, the variable resistor

typically used for volume controls can be seen on the far right. Its value is very

easy to adjust. The four resistors at the center of the photograph are the semi-



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fixed type. These ones are mounted on the printed circuit board. The two

resistors on the left are the trimmer potentiomeers.This symbol is used toindicate a variable resistor in a circuit diagram.

Resistor color code

Color Value MultiplierTolerance

(%)

Black 0 0 -

Brown 1 1 1



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Example 1(Brown=1),(Black=0),(Orange=3)

10 x 103 = 10k ohmTolerance(Gold) = 5%

Example 2

(Yellow=4),(Violet=7),(Black=0),(Red=2)

470 x 102 = 47k ohm

Tolerance(Brown) = 1%

CAPACITOR

The capacitor's function is to store electricity, or electrical energy.

The capacitor also functions as a filter, passing alternating current (AC), and

blocking direct current (DC).This symbol is used to indicate a capacitor

in a circuit diagram. The capacitor is constructed with two electrode plates

facing each other, but separated by an insulator. When DC voltage is applied to

the capacitor,an electric charge is stored on each electrode. While the capacitor

is charging up, current flows.The current will stop flowing when the capacitor

has fully charged.The capacitance of a capacitor is generally very small, so

units such as the microfarad (10-6F ), nanofarad (10-9F ), and Pico farad (10-12F )

are used. Recently, a new capacitor with very high capacitance has been

developed. The Electric Double Layer capacitor has capacitance designated inFarad units. These are known as "Super Capacitors. The capacitor has an

insulator (the dielectric) between 2 sheets of electrodes. Different kinds of

capacitors use different materials for the dielectric.



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Types of capacitors

Electrolytic Capacitors

Aluminum is used for the electrodes by using a thin oxidization membrane.

Large values of capacitance can be obtained in comparison with the size of the

capacitor, because the dielectric used is very thin. The most important

characteristic of electrolytic capacitors is that they have polarity. They have a

positive and a negative electrode. [Polarized] This means that it is very

important which way round they are connected. If the capacitor is subjected to

voltage exceeding its working voltage, or if it is connected with incorrect

polarity, it may burst. It is extremely dangerous, because it can quite literally

explode. Generally, in the circuit diagram, the positive side is indicated by a "+"

(plus) symbol.

Electrolytic capacitors range in value from about 1F to thousands of

F.Mainly this type of capacitor is used as a ripple filter in a power supply

circuit, or as a filter to bypass low frequency signals, etc.

.



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Ceramic Capacitors

Ceramic capacitors are constructed with materials such as titanium acid barium

used as the dielectric. Internally, these capacitors are not constructed as a coil,

so they can be used in high frequency applications. Typically, they are used in

circuits which bypass high frequency signals to ground.These capacitors have

the shape of a disk. Their capacitance is comparatively small.The capacitor on

the left is a 100pF capacitorwith a diameter of about 3 mm.The capacitor on

the right side is printed with 103, so 10 x 103pF becomes 0.01 F. The diameter

of the disk is about 6 mm.Ceramic capacitors have no polarity.Ceramic

capacitors should not be used for analog circuits, because they can distort the

signal.

DIODE

A diode is a semiconductor device which allows current to flow through it in

only one direction. Although a transistor is also a semiconductor device, it does



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not operate the way a diode does. A diode is specifically made to allow current

to flow through it in only one direction

A diode can be used as a rectifier that converts AC to DC for a power supply

device.

Diodes can be used to separate the signal from radio frequencies.

Diodes can be used as an on/off switch that controls current.

This symbol is used to indicate a diode in a circuit diagram.

TRANSISTOR

The transistor's function is to amplify an electric current.Many different kinds

of transistors are used in analog circuits, for different reasons. This is not the

case for digital circuits. In a digital circuit, only two values matter on or off.

The amplification ability of a transistor is not relevant in a digital circuit. In

many cases, a circuit is built with integrated circuits.Transistors are often used

in digital circuits as buffers to protect ICs. For example, when powering an

electromagnetic switch (called a 'relay'), or when controlling a light emittingdiode.Two different symbols are used for the transistor.



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PNP type and NPN type .

A transistor is a semiconductor device, commonly used as an amplifier. Because

of its fast response and accuracy, the transistor may be used in a wide variety of

digital and analog functions, including amplification, switching, voltage

regulation, signal modulation, and oscillators. Transistors may be packaged

individually or as part of an integrated circuit chip, which may hold thousands of

transistors in a very small area.

CRYSTAL OSCILLATOR

A crystal oscillator is an electronic circuit that uses the mechanical resonance of

a vibrating crystal of piezoelectric material to create an electrical signal with a

very precisefrequency. This frequency is commonly used to keep track of time

http://en.wikipedia.org/wiki/Frequencyhttp://en.wikipedia.org/wiki/Frequencyhttp://en.wikipedia.org/wiki/Frequency


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(as in quartz wristwatches), 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 designed around them were called "crystal oscillators".

TRANSFORMER

Transformers for use at power or audio frequencies have cores made of many

thin laminations of silicon steel. By concentrating the magnetic flux, more of it

is usefully linked by both primary and secondary windings. Since the steel core

is conductive, it, too, has currents induced in it by the changing magnetic flux.

Each layer is insulated from the adjacent layer to reduce the energy lost to eddy

current heating of the core. The thin laminations are used to reduce the eddy

currents, and the insulation is used to keep the laminations from acting as a

solid piece of steel. The thinner the laminations the lower the eddy currents, and

the lower the losses. Very thin laminations are generally used on high frequency

transformers. The cost goes up when using thinner laminations mainly over the

labor in stacking them.



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PRINTED CIRCUIT BOARD

When assembling an electronic circuit, a board is needed on which the

components can be mounted and wired together. This board is called a Printed

Wiring Board (PWB).In Japan, the printed wiring board used to be called a

"Printed Circuit Board." Nowadays in Japan the name "Printed Circuit Board"

is not used because the initials of "Printed Circuit Board" are "PCB." PCB also

stands for "Polychlorinated Biphenyls (PCBs)," which is a poison. So in Japan,

we refer to the boards as "Printed Wiring Boards." In other countries, they are

still referred to as "Printed Circuit Boards," or PCBs.

In electronics, printed circuit boards, or PCBs, are used to

mechanically support and electrically connect electronic components using



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conductive pathways, or traces, etched from copper sheets laminated onto a

non-conductive substrate. PCBs are rugged, inexpensive, and can be highly

reliable. They require much more layout effort and higher initial cost than either

wire-wrapped or point-to-point constructed circuits, but are much cheaper,

faster, and consistent in high volume productionMaking a PWB takes a lot of

work, and can be very difficult.

WIRING MATERIAL

Wire is used to electrically connect circuit parts, devices, equipment etc.There

are various kinds of wiring materials. The different types of wire can be divided

largely into two categories: single wire and twisted strand wire. It really doesn't

matter which kind you use for a given application, but usually, single wire is

used to connect devices (resistors, capacitors ect) together on the PWB. (Parts

that don't move)It is also used for jumper wiring.Twisted strand wire can bend

freely, so it can be used for wiring on the PWB, and also to connect discrete



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pieces of equipment.If single wire is used to connect separate equipment, it will

break soon, as it is not very flexible.It is convenient to use the single tin coated

wire of the diameter 0.32 mm for the wiring of PWB. If the diameter is larger,

soldering becomes a little bit difficult. And if the diameter is too thin, it

becomes difficult to bend the wire the way you want it to stay. It's best to use

whatever wire you are comfortable with, and not worry about those things.



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PROJECT REPORT



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COMPONENT LIST

S.NO. NAME OF COMPONENT VALUE

1) PCB 4.5

2) Connector 3 pin

3) Transformer 220V

4) Diode IN4001

5) Capacitor-1 10uf,50V

6) Capacitor-2 1000uf,25V

7) Capacitor-2 33pf

8) Resistor 10k

9) Regulator IC 7805

10) Crystal oscillator 11.0592

11) Microcontroller AT89C52

12) Potentiometer 10K

13) LCD JMD142A

14) Berge stick

15) Connecting wires

Chitkara University, Himachal Pradesh 28


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CIRCUIT DIAGRAM



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CIRCUIT DESCRIPTION

As seen in the circuit diagram the pin no. 9 is a reset pin and is used to develop a pulse from low to

high when we are required to reset the controller.The switch across the capacitor will do this as one of

the terminal of the switch is attached to VCC.When it is pressed the VCC reaches the controller pin

no.9 and will reset it.

Next to it is pin no.18 and 19 to which crystal circuit is fixed.the crystal has got a frequency

of 11.0592 Mhz with two small capacitors of 33pf each.these are used to avoid the frequency noise in

the circuit.the pin no.20 is a ground pin and connected to the ground of the supply section.The pin

no.20 is a supply pin thus it is attached to the VCC which is +5V dc.The pin no.31 is Vpp pin and is

shorted with pin no.40 to give it VCC.

In front of port 0 and port 2 we have fixed pin type connectors called berge sticks.this we

have attached to make our card flexible to use so that it may pick the out from this stick and attach it

with the application circuitry in order to drive it using connectors.the port 0 is not internally pulled up

port so we have to use external pull up by putting a SIP of 10K.It is also shown in the circuit the SIP is

nothing but a resistor network of a fixed value and is used to fix provide the necessary external voltage

to the ports so that they can be used at the time of sourcing the current to any external device.

The complete components were with us and we are suppose to make a power supply

section.for this section we are suppose to generate a 5V dc supply at the output.This is then used as

VCC for the controller and even for the application circuitry.

POWER SUPPLY UNIT

Power supply is a reference to a source of electrical power .a device or a system that supplies electrical

or other type of energies to an output load or group of loads is called a power supply unit.



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REGULATED POWER SUPPLY

A Regulated power supply circuit that is an electronic circuit that is designed to provide a constant

voltage of predetermined value across the load terminals irrespective to the main function.A regulated

power supply circuit consists of a transformer to step down the ac mains voltage to the required value.

The output of the transformer is fed to the rectifier circuit which converts the ac voltage into

pulsating dc voltage. In series with the rectifier, the filter circuit is connected which filters out the

pulsating dc voltage into pure dc voltage. Then the output is connected to the voltage regulator circuit,

which regulates the dc output and converts it into constant dc supply, which can be then fed to the

electronics circuits. The circuit for the regulated supply circuit is as shown below

For example a 5V regulated supply:

C 1

1 0 0 0 u f / 2 5 v

T 1

2 2 0 V

1 5

6

4 8

5 v

C 2

1 0 0 0 u f /

U 1L M 7 8 0 5

1

2

3V I

G

N

D

V O

D 2I N 4 0 0 7

D 1

I N 4 0 0 7 J 1

C

1

2

After doing this we have fixed the controller base and its associated circuitry with all the precautions as

if reset circuit should be properly bias and crystal should be proper and moreover the pin no.31 should

be well short circuited with the controllers pin no 40 to have VCC.



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MICROCONTROLLER 8051

Microcontroller (also MCU or C) is a computer-on-a-chip. It is a type of microprocessor emphasizing

high integration, low power consumption, self-sufficiency and cost-effectiveness, in contrast to ageneral-purpose microprocessor (the kind used in a PC). In addition to the usual arithmetic and logic

elements of a general purpose microprocessor, the microcontroller typically integrates additional

elements such as read-write memory for data storage, read-only memory, such as flash for code

storage, EEPROM for permanent data storage, peripheral devices, and input/output interfaces. At clock

speeds of as little as a few MHz or even lower, microcontrollers often operate at very low speed

compared to modern day microprocessors, but this is adequate for typical applications. They consume

relatively little power (milliwatts), and will generally have the ability to sleep while waiting for an

interesting peripheral event such as a button press to wake them up again to do something.

Description

The AT89C2051 is a low-voltage, high-performance CMOS 8-bit microcomputer with 2K bytes of

Flash programmable and erasable read-only memory (PEROM). The device is manufactured using

Atmels high-density nonvolatile memory technology and is compatible with the industry-standard

MCS-51 instruction set. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the

Atmel AT89C2051 is a power-full microcomputer which provides a highly-flexible and cost-effectivesolution to many embedded control applications. The AT89C2051 provides the following standard

features: 2K bytes of Flash, 128 bytes of RAM, 15 I/O lines, two 16-bit timer/counters, a five vector

two-level interrupt architecture, a full duplex serial port, a precision analog comparator, on-chip

oscillator and clock circuitry. In addition, the AT89C2051 is designed with static logic for operation

down to zero frequency and supports two software selectable power saving modes. The Idle Mode

stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue

functioning. The power-down mode saves the RAM contents but freezes the oscillator disabling all

other chip functions until the next hardware reset.



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Special features of 8051 are

8-bit data bus

16-bit address bus

32 general purpose registers each of 8 bits

16 bit timers (usually 2, but may have more, or less).

3 internal and 2 external interrupts.

Bit as well as byte addressable RAM area of 16 bytes.

Four 8-bit ports, (short models have two 8-bit ports).

16-bit program counter and data pointer

PIN DESCRIPTION OF 8051

The microcontroller has total forty pins in all. Most of the pins of 8051 microcontroller have more than

one function. The first function is the input /output operation and the second function can be some

special function like they can be used as counters or for serial communication. In microcontroller there

are four ports (collection of pins) P0, P1, P2 &P3. These ports have 8 pins each as shown. As we will

see later on we will be able to address the whole port during programming. Whenever we are talking

about 8051 we are talking of the family of microcontrollers having the architecture of 8051. They are

all same except for some additional features, pins distribution and packaging.

PORT 0: Serve as an i/p, o/p or when used together as a bi-directional low order address and data bus

for external memory. When used as i/p, a 1 must be written to the corresponding port 0 latches by the

prg, thus turning both of o/p transistors off, which in turn causes the pin to float in a high impedance

state, and the pin is essentially connected to i/p buffer. When used as o/p, the pin latches that areprogrammed to a 0 will turn on the lower FET grounding the pin.



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PORT 1: Port 1 pins have no dual functions, therefore the output latch is connected directly to the gate

of the lower FET, which has an FET circuit labeled internal FET pull-up as an active pull-up load.

Used as an i/p, a 1 is written to the latch, turning the lower FET off; the pin and the i/p to the pin buffer

are pulled high by the FET load. An external ckt can overcome the high impedance pull-up and drive

the pin low to i/p a 0 or leave the i/p high for a 1.If used as o/p, the latches containing a 1 can derive

the input of an external ckt high through the pull-up. If a 0 is written to the latch, the lower.FET is on,

the pull-up is off, and the pin can drive the i/p of the external ckt low.

PORT 2: This may be used as the I/O port similar in operation to the port 1.The alternate use of this

port is to supply a high order address byte in conjunction with the port 0 low-order byte to address

external memory. Port 2 pins are momentarily changed by the address control signals when supplying

the high byte of a 16-bit address. Port 2 latches remain stable when external memory is addressed as

they do not have to be turned around {set to 1}for data i/p as the case of port 0.

PORT 3: Is an i/o port similar to port 1.the i/o functions can be programmed under the control of the

p3 latches or under the control of the various other SFRs.The port 3 alternate uses are also shown in

table: Unlike P0, P2 which can have external addressing functions and change all eight port bits when

in alternate use, each pin of port 3 may be individually programmed to be used either as I/O or as one

of the alternate functions.

PIN 40 &20 (VCC and GND):The pin 40 is Vcc i.e. it is given 5V and pin 20 is GND i.e. it is given

0V (supplied from power source) for powering up the microcontroller. Pins 40 and 20 are VCC and

ground respectively. The 8051 chip needs +5V 500mA to function properly, although there are lower

powered versions like the Atmel 2051 which is a scaled down version of the 8051 which runs on +3V.



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PIN 9 RESET PIN CONNECTIONS (RST): PIN 9 is the reset pin which is used reset the

microcontrollers internal registers and ports upon starting up.2 machine cycle should be high at this

pin. The reset pin i.e. pin number 9 is used to reset the program just like we restart a computer, the

program starts executing from the very beginning. When reset is used the program counter is set back

to zero and the values in all other registers are lost.



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PINS 18 & 19 CONNECTING THE CRYSTAL (XTAL1- XTAL2): The 8051 has a built-in

oscillator amplifier hence we need to only connect a crystal at these pins to provide clock pulses to the

circuit. The 8051 requires the existence of an external oscillator circuit. The oscillator circuit usually

runs around 12MHz, although the 8051 (depending on which specific model) is capable of running at a

maximum of 40MHz. Each machine cycle in the 8051 is 12 clock cycles, giving an effective cycle rate

at 1MHz (for a 12 KHz clock) to 3.33MHz (for the maximum 40MHz clock).The heart of 8051 is the

circuitry that generates the clock pulses by which all internal operations are synchronised.Pins XTAL1

and XTAL2 are provided for connecting a resonant circuit to form an oscillator. Typically quartz crystal

and capacitors are employed. The crystal frequency is the basic internal clock frequency of the

microcontroller. The pin numbers 18 - 19 are used to connect the crystal. The frequency of this crystal

determines the machine cycle.

PINS 29, 30 & 31: As described in the features of the 8051, this chip contains a built-in flash memory.

In order to program this we need to supply a voltage of +12V at pin 31. If external memory is

connected then PIN 31, also called EA/VPP, should be connected to ground to indicate the presence of

external memory. PIN 30 is called ALE (address latch enable), which is used when multiple memory

chips are connected to the controller and only one of them needs to be selected. We will deal with this

in depth in the later chapters. PIN 29 is called PSEN. This is "program select enable". In order to use

the external memory it is required to provide the low voltage (0) on both PSEN and EA pins.



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LIQUID CRYSTAL DISPLAY

A liquid crystal display (LCD) is a thin, flat panel used for electronically displaying information such

as text, images, and moving pictures. Its uses include monitors for computers, televisions, instrument

panels, and other devices ranging from aircraft cockpit displays, to every-day consumer devices such

as video players, gaming devices, clocks, watches, calculators, and telephones. Among its major

features are its lightweight construction, its portability, and its ability to be produced in much larger

screen sizes than are practical for the construction of cathode ray tube (CRT) display technology. Its

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

an electronically-modulated opticaldevice made up of any number of pixels filled with liquid crystals

and arrayed in front of a light source (backlight) or reflector to produce images in color or

monochrome. The earliest discoveries leading to the development of LCD technology date from 1888.

By 2008, worldwide sales of televisions with LCD screens had surpassed the sale of CRT units.

The most commonly used LCDs found in the market today are 1 line,2 lines or 4 lines LCDs which

have only one controller and support at most 80 characters , whereas LCDs supporting more than 80characters make use of 2 HD44780 controllers. Most LCDs with 1 controller has 14 pins and LCDs

with 2 controllers have 16 pins.

http://en.wikipedia.org/wiki/Battery_(electricity)http://en.wikipedia.org/wiki/Reflectorhttp://en.wikipedia.org/wiki/Battery_(electricity)http://en.wikipedia.org/wiki/Reflector


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LCD pin descriptions:

The LCD discussed in this section has 14 pins. The function of each pin is given in table.

Vcc, Vss, and VEE: While Vcc and Vss provide +5V and ground, respectively, VEE is used for

controlling LCD contrast.

RS register select: There are two very important registers inside the LCD. The RS pin is used for

their selection as follows. If RS = 0, the instruction command code register is selected, allowing the

user to send a command such as clear display, cursor at home, etc. If RS = 1 the data register is

selected, allowing the user to send data to be displayed on the LCD.



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R/W read/write: R/W input allows the user to write information to the LCD or read information

from it. R/W = 1 when reading; R/W =0 when writing.

E Enable: The enable pin is used by the LCD to latch information presented to its data pins. When

data is supplied to data pins, a high to low pulse must be applied to this pin in order for the LCD to

latch in the data present at the data pins. This pulse must be a minimum of 450 ns wide.

D0 D7: The 8 bit data pins, D0 D7, are used to send information to the LCD or read the contents of

the LCDs internal registers.To display letters and numbers, we send ASCII codes for the letters A Z,

a z, and numbers 0 9 to these pins while making RS = 1.There are also instructions command

codes that can be sent to the LCD to clear the display or force the cursor to the home position or blink

the cursor. Table below lists the instruction command codes.



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We also use RS = 0 to check the busy flag bit to see if the LCD is ready to receive information. The

busy flag is D7 and can be read when R/W =1 and RS = 0, as follows: if R/W =1, RS =0. When D7 =

1(busy flag = 1), the LCD busy taking care of internal operations and will not accept any new

information. When D7 = 0, the LCD is ready to receive new information. Note: It is recommended to

check the busy flag before writing any data to the LCD.

Data display: In LCD, one can put data at any location. The following shows address locations

and how they are accessed:

RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0

0 0 1 A A A A A A A



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LCD addressing

DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0

Line 1(max.) 1 0 0 0 0 0 0 0

Line 1(min.) 1 0 1 0 0 1 1 1

Line 2(max.) 1 1 0 0 0 0 0 0

Line 2(min.) 1 1 1 0 0 1 1 1

The upper address range can go as high as 0100111 for 40 character-wide LCD while for the

20 character-wide LCD it goes up to 010011 (19 decimal = 10011 binary). Notice that the upper range

0100111 (binary) = 39 decimal which corresponds to locations 0 to 39 for the LCDs of 40*2 size.

Interfacing LCD to 8051

The 44780 standard requires 3 control lines as well as either 4 or 8 I/O lines for the data bus. The user

may select whether the LCD is to operate with a 4-bit data bus or an 8-bit data bus.

If a 4-bit data bus is used, the LCD will require a total of 7 data lines.If an 8-bit data bus

is used, the LCD will require a total of 11 data lines.The three control lines are EN, RS, and RW. Note

that the EN line must be raised/lowered before/after each instruction sent to the LCD regardless of



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whether that instruction is read or write text or instruction. In short, you must always manipulate EN

when communicating with the LCD. EN is the LCD's way of knowing that you are talking to it. If you

don't raise/lower EN, the LCD doesn't know you're talking to it on the other lines.

PRACTICAL CONNECTIONS

The figure below shows a general way in which we can connect a LCD to the microcontroller .Here

the figure shows 8051 controller, the same way we can use AT89C92 controller as we have used in our

trainiong session.The LCD over here is attached to port 0 and in our training project we have attached

it to port 3.

Concept of programming



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A computer can do what programmer ask to do.To perform a particular task theprogrammer prepare the

sequence of instructions called a program. A set of program written for particular computer is known as

software for that computer. The program is stored in RAM. The instructions are coded and stored in the

memory in the form of 0s and 1s.A program written in the form of 0s and 1s is known as machine

language program.

DEMERITS OF MACHINE LANGUAGE PROGRAM

1. It is very difficult to understand or debug a program.

2. Since the each bit has to be entered individually the entry of a program is very slow.

3. Programs are long.

4. Program writing is difficult and tiresome.

5. Chances of careless errors in writing yhe program.

ASSEMBLY LANGUAGE: The writing of program in machine language is difficult, tiresome,

boring, and errorprone. A pprogrammer can easily write a program in alphanumeric symbols

instead of 0s and 1s. A program written in mnemonics is known as assembly language program.

COMPILER: A program that translates a high-level program into machine language is known as

compiler.

ASSEMBLER: A program that translates an assembly language program into machine language

prorram is known as assembler.

Finally we have reached a point where we have to insert the brain to the controller and we were ready

to do so.We used the most famous software to write programs in assembly language in it and this

software is called KEIL micro-vision-3. This software has got in built assembler as well as compiler

as well as compiler to generate required hex file is to be burned in the controller.

SOLDERING



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The electronic industry depends upon very much on the solder joints. Soldering is an alloying process

b\w two meters or soldering as a method of making reliable joints is one of the widely practiced

production techniques.

SOLDERING EQUIPMENT

If the number of PCBs and components to be soldered are less, hands soldering process is used.

Following are the tools used:

1. Soldering Iron

2. Solder

3. Soldering Fluxes

4. Tools

1. SOLDERING IRON

It is reasonable priced electrical equipment. It supplies sufficient heat transformer when the iron tip is

applied to connection to be soldered. Soldering irons are of different Temperature ranges. Soldering

irons are divided in two groups: -

1.1 Soldering iron or pencils

1.2 Soldering guns



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2. SOLDER

It is the oldest and most widely used alloy. It is a genes name representing a host of alloys of raw

melting materials like tin, lead, cadmium, bismuth, sodium silver and many more. An alloy is not just a

mixture but also an exact combination of two or more metals to get an entirely new set of desired

properties.

3. FLUXES

During soldering operations an auxiliary medium is most commonly used to increase the flow

properties of molten solder to improve the degree of melting and remove the oxide film from the base

metal which prevents the film from reforming so that the liquid solder can display the flux and react

with the base metal to form a bond characteristics of flux.

DESOLDERING

At some stage you will probably need to desolder a joint to remove or re-position a wire or component.

There are two ways to remove the solder:

With a desoldering pump (solder sucker)

With solder remover wick (copper braid)



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APPLICATIONS

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

automobile engine control systems, remote controls, office machines, appliances, power tools, andtoys. LCD interfaced with microcontroller can also be used in various applications such as written

below:

Home automatic products like air conditioners, security monitoring system.

House holds appliances like microwave oven, washing machines

Medical equipments

Digital multimeter, voltmeter, calculators and watches

Moving display in Malls, Banks etc.

Parking system

.



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CONCLUSION

After completing the project, we learnt much things.Our interest in practical work also increased.We

had learned the following things: -

How to read the circuit Diagram?

How to identify the components?

How to assemble the given components with the help of circuit Diagram on the PCB?

To know how the interfacing of LCD can be done with microcontroller 8051?

How the micro-controller works?

How to eliminate any fault if occurs?

How to solder/desolder the components efficiently?

What practical works provides us and how accuracy, efficiency can be got in the work?



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BIBLOGRAPHY

DAILY DIARY

BOOKS

Muhammad Ali Mazidi, Janice Gillispie Mazidi, Rosin D. Mc Kinlay, the 8051

Microcontroller

& Embedded Systems, Pearson Education Inc. 2nd Edition, 2008.

Kenneth J Ayala, the 8051 Microcontroller Architecture, Programming & Applications

Penram International, 2nd Edition, 1996.

J B Gupta,Electronics Devices and Circuits, KATSON Books, India

Electronics for You

Electronics devices and circuits

Electronics manufacturing

Technique serials

Electronics components and materials

WEB RESOURCES

http://www.8051projects.net/forum

http://www.datasheetdirect.com

http://www.medicaid.co.in

www.electronicsforyou.com

http://www.google.com

www.alldatasheets.com

www.wikipedia.com



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Electronic Lock Code System

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