guru tegh bahadur institute by manpreet

7/31/2019 Guru Tegh Bahadur Institute by Manpreet

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GURU TEGH BAHADUR INSTITUTE

OF TECHNOLOGY

G8 AREA -RAJOURI GARDEN

NEW DELHI-110027

SUMMER TRAINING PROJECT REPORT

ON

EMBEDDED SYSTEMS AND ROBOTICS

NAME: MANPREET SINGH

BRANCH: ECE-2

E.NO: 07913202809

SEMESTER: 5TH


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TABLE OF CONTENTS

Acknowledgements

Certificate

Objective

abstract

Introduction

Microcontrollers and Microprocessors

Embedded Systems

Types of Microcontrollers

8051 family

Harvard Architecture

8051 Architecture

Types of memory

Addressing modes

Timers

Interrupts Serial ports communication

Project description

appendix

References and bibliography


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AKNOWLEDGEMENTS

We would also like to express our gratitude to Prof. Amrik Singh Head of the

Department, Elect ron ics & Communication Engineer ing, Guru Tegh Bahadur

Institute of Technology, for encouraging and inspiring us to carry out the project in

the Project lab.

We would also like to thankMr. Pawan Kumar and Mr. Gurmeet singh who have

given us unconditional support and help. Without their invaluable inputs and

distinguished guidance we could not have presented this dissertation up to the present

standard.

From materializing the idea to executing it and finally completing it, we were faced

with numerous challenges, all these people stood by us through thick and thin and

with their superior guidance and wisdom saw us through all of them.

We would also like to thank all the staff members of Guru Tegh Bahadur Institute of

Technology for providing us with the required facilities and support towards the

completion of the project.

Date:


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CERTIFICATE

SUMMER TRAINING

ON

EMBEDDED SYSTEMS AND ROBOTICS

ORGANISED BY

THE DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING

This is to certify that Mr. MANPREET SINGH Enrolment No 07913202809

Of B.Tech E.C.E branch, fourth semester has attended Embedded Systems and

Robotics course of 6 weeks summer training programme at Guru Tegh Bahadur

Institute of Technology


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OBJECTIVE

ACADEMIC OBJECTIVE

Study basics of Microcontroller 8051 and its interfacing with different components

like LED, LDR, LCD, 7 Segments, Motors.

To have a command on programming the microcontroller using assembly language.

To learn basics of EMBEDDED SYSTEMS AND ROBOTICS.

PROJECT OBJECTIVE

Burglar detection - Burglars don't like alarm systems because they

provide too much risk of being caught, so most burglar will move on to a

home without a system.

Reducing loss - When you have a security system, it will work to deter

burglars from entering your home, which means that it is also minimizing

your chances of losing your possessions.

Prevent a confrontation - By having an alarm system, the alarm will sound

if an intruder breaks in, so if you come home and the alarm is sounding, you

know not to go into your home. This is the best way to avoid a confrontation

with a burglar, which can be traumatic for anyone.

Fire detection - Most of the alarms these days have a way that you can hook

up your smoke alarms to them. That way if a fire is detected, the alarm will

sound alerting you to the danger. It will also alert the security company to the

danger so they can call for help for you. This could save your family's lives.


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ABSTRACT

Engineering is not only a theoretical study but it is a implementation of all we study

for creating something new and making things more easy and useful through practical

study. It is an art which can be gained with systematic study, observation and practice.

In the college curriculum we usually get the theoretical knowledge of industries, and a

little bit of implementation knowledge that how it is works? But how can we prove

our practical knowledge to increase the productivity or efficiency of the industry?

Dont take the chance of becoming victim of burglary, which is often accompanied by

violence. Protect our family and valuables with this microcontroller based security

system that will let us rest our head knowing that should anyone trying to break into

our home, an alarm will go off and the police will be alerted immediately.

The transmitter section continuously transmits IR rays which are received by thereceiver section. The signal is received by photodiode, which further connected to a

microcontroller, in which we done a programming.

When the IR signal is interrupted, the microcontroller starts working as per the

program burnt into the EPROM and control the siren, telephone and cassette player

via the respective relays.


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INTRODUCTION

This training report is all about the embedded systems and its application in various

fields of real world. We are living in the Embedded World. We are surrounded with

many embedded products and our daily life largely depends on the proper functioning

of these gadgets. Television, Radio, CD player, Washing Machine or Microwave

Oven in our kitchen, Card readers, Access Controllers, Palm devices of our work

space enable us to do many of our tasks very effectively. Apart from all these, many

controllers embedded in our car take care of car operations between the bumpers. All

kinds of magazines and journals regularly dish out details about latest technologies,

new devices; fast applications which make us believe that our basic survival is

controlled by these embedded products. Now we can agree to the fact that these

embedded products have successfully invaded into our world. What is this Embedded

System?

Theoretically, an embedded controller is a combination of piece of

microprocessor based hardware and the suitable software to undertake a

specific task.

I have made a Project based on Microcontroller that is a Prototype Home security

system. This training report covers all about the microcontroller and project

description.


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BODY OF THE REPORT

IDENTIFICATION OF DIFFERENT ELECTRONICS

COMPONENTS

SOLDERING IRON: - A soldering iron is a hand tool most commonly used in

soldering. It supplies heat to melt the solder so that it can flow into the joint between

two work pieces.

A soldering iron is composed of a heated metal tip and an insulated handle. Heating is

often achieved electrically, by passing an electric current (supplied through an

electrical cord or battery cables) through the resistive material of a heating element.

Another heating method includes combustion of a suitable gas, which can either be

delivered through a tank mounted on the iron (flameless), or through an external

flame.

LED: A light-emitting diode (LED) is a semiconductor light source. LEDs are used

as indicator lamps in many devices and are increasingly used for other lighting.

Introduced as a practical electronic component in 1962, early LEDs emitted low-

intensity red light, but modern versions are available across the visible, ultraviolet and

infrared wavelengths, with very high brightness.

When a light-emitting diode is forward biased (switched on), electrons are able to

recombine with electron holes within the device, releasing energy in the form of

photons. This effect is called electroluminescence and the color of the light

(corresponding to the energy of the photon) is determined by the energy gap of the

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

optical components may be used to shape its radiation pattern. LEDs present many

advantages over incandescent light sources including lower energy consumption,

longer lifetime, improved robustness, smaller size, faster switching, and greater


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durability and reliability. LEDs powerful enough for room lighting are relatively

expensive and require more precise current and heat management than compact

fluorescent lamp sources of comparable output.

Light-emitting diodes are used in applications as diverse as replacements for aviation

lighting, automotive lighting (particularly brake lamps, turn signals and indicators) as

well as in traffic signals. The compact size, the possibility of narrow bandwidth,

switching speed, and extreme reliability of LEDs has allowed new text and video

displays and sensors to be developed, while their high switching rates are also useful

in advanced communications technology. Infrared LEDs are also used in the remote

control units of many commercial products including televisions, DVD players, and

other domestic appliances.

LED voltage usually 2V, but 4V for blue and white LEDs

LED current 10mA = 0.01A, or 20mA = 0.02A

RESISTANCE: - A linear resistor is a two-terminal, linear, passive electronic

component that implements electrical resistance as a circuit element. The

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

the resistor's terminals. Thus, the ratio of the voltage applied across resistor's

terminals to the intensity of current flowing through the resistor is called

resistance. This relation is represented with a well-known Ohm's law:

Resistors are common elements of electrical networks and electronic circuits and are

ubiquitous in most electronic equipment. Practical resistors can be made of various

compounds and films, as well as resistance wire (wire made of a high-resistivity

alloy, such as nickel-chrome). Resistors are also implemented within integrated

circuits, particularly analog devices, and can also be integrated into hybrid and

printed circuits.


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CAPACITOR: - A capacitor (formerly known as condenser) is a passive electrical

component used to store energy in an electric field. The forms of practical capacitors

vary widely, but all contain at least two conductors separated by a non-conductor.

Capacitors used as parts of electrical systems, for example, consist of metal foils

separated by a layer of insulating film.

A capacitor is a passive electronic component consisting of a pair of conductors

separated by a dielectric (insulator). When there is a potential difference (voltage)

across the conductors, a static electric field develops across the dielectric, causing

positive charge to collect on one plate and negative charge on the other plate. Energy

is stored in the electrostatic field. An ideal capacitor is characterized by a single

constant value, capacitance, measured in farads. This is the ratio of the electric charge

on each conductor to the potential difference between them.

Capacitors are widely used in electronic circuits for blocking direct current while

allowing alternating current to pass, in filter networks, for smoothing the output of

power supplies, in the resonant circuits that tune radios to particular frequencies and

for many other purposes.


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INTRODUCTION OF MICROCONTROLLER:

A digital computer typically consists of three major components: the Central

Processing Unit, program and data memory and input/output systems. The CPU

controls the flow of information among the components of the computers. it also

processes the data by performing digital operations .most of the processing is done

arithmetic logical unit(ALU) within the CPU. When the CPU of a computer is built

on single printed circuit board then the computer is called minicomputer. A

microprocessor is a CPU which is compacted into a single-chip semiconductor device.Microprocessors are general purpose device suitable for many applications. A

computer built around a micro processor is called microcomputer. The choice of

input/output and memory device of a microcomputer depends upon the specific

applications.

A microcontroller is an entire computer built on a single chip. Microcontrollers are

usually dedicated devices embedded within an application. For example

microcontrollers are used in engine controllers in automobiles and exposure and focus

controller in cameras.

In order to serve this application, they have high concentration of on-chip facilities

such as serial ports, parallel I/O ports, timers, counters; interrupt control, analog to

digital converter, RAM, ROM etc.


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Microcontroller v/s Microprocessor

Microcontrollers differ from microprocessors in several ways. The main characteristic

of microcontrollers is their wide variety of on-chip peripheral functions and memory

that enable them to provide a single chip solution to many dedicated embedded

designs.

Microprocessors such as the Pentium inside a personal computer have only the

Central Processing Unit and Math Co-processing unit. These microprocessors do not

have built in memory, input or output functions such as parallel ports or serial ports

etc. They are optimized to provide only the raw arithmetic and logic functions

required by the operating system at the highest speed. All other components requiredto make the computer such as memory, input/output ports, serial, parallel, and mass

storage are provided by external chips and devices. The Pentium is designed to meet a

broad range of general computing needs that are provided with a personal computer.

A microprocessor such as the Pentium inside a personal computer normally has a very

large instruction set. In the case of the Pentium it is several hundred instructions. The

instructions cover a very broad range of tasks and functions. Some of these

instructions can be complex and take many internal steps to execute within the

processor. In computer jargon we categorize this type of instruction set as CISC or

Complex Instruction Set Computer. CISC has its advantages in the area that it is used

in such as high level languages and operating systems.


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One more characteristic of the microprocessor inside the personal computer is the way

it is attached to and uses memory. The read/write memory inside a pc is one very

large block of contiguous memory bytes. A typical PC may have between 256

Megabytes and 2 Gigabytes of RAM memory. This memory is used to store both

programs and data. The program that is running must keep track of what areas are

used for data and what areas are used for program instructions. A computer that usesthe same memory space for both data and program instructions is classified as

the Von Neumann architecture.

When we look at a typical microcontroller one of the first things we notice is that themicrocontroller contains its own memory, parallel ports, clock and very often a good

number of peripheral functions not found on a microprocessor. In the case of PIC

microcontrollers we will find both flash program memory where instructions are

stored and a separate ram memory space where only data is stored. Computers that

have separate memory spaces for data and program instructions are classified as

the Harvard Architecture. One particular advantage of the Harvard Architecture is

that data access operations can be taking place simultaneously with program

instruction execution. Each memory area has its own data bus to the CPU so

operations can go on during the same time frame. Many different manufacturers use

the Harvard Architecture for designs of microcontrollers because this design is veryefficient for designing specific purpose controllers that go into other systems.


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Microcontrollers usually get embedded into other products such as microwave ovens,

automobile engine controllers, power tools, appliances, industrial instruments, hand

held devices, cell phones and many other areas. The design and programming for

these types of products and applications has become so specialized that it has taken on

its own identity as embedded design.

The PIC microcontroller also has a very different type of instruction set. Theparticular PIC microcontroller located on the trainer board we will be using is the

PIC16F877A. This is in the midrange family but its capabilities are at the top end of

the midrange family. This unit only uses 35 instructions! This is the same for all

microcontrollers in the midrange family. The strategy that is used in the design of this

type of microcontroller is to make a few very simple instructions that execute very

fast. Using this strategy a complex task can be accomplished with the combination of

many very fast simple instructions in a relatively short time. Computers that use just a

small number of very simple instructions that execute very fast are classified

as RISC or Reduced Instruction Set Computers. Since PIC microcontrollers use only

35 very simple instructions they fit neatly into this category.


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EMBEDDED SYSTEMS

Any appliance that has a digital clock, for instance, has a small embedded

microcontroller that performs no other task than to display the clock. Modern cars

have embedded computers onboard that control such things as ignition timing andanti-lock brakes using input from a number of different sensors.

Embedded computers rarely have a generic interface, however. Even if embedded

systems have a keypad and an LCD display, they are rarely capable of using many

different types of input or output. An example of an embedded system with I/O

capability is a security alarm with an LCD status display, and a keypad for entering a

password.

In general, an Embedded System:

Is a system built to perform its duty, completely or partially independent of human

intervention.

Is specially designed to perform a few tasks in the most efficient way.

Interacts with physical elements in our environment, viz. controlling and driving a

motor, sensing temperature, etc.

An embedded system can be defined as a control system or computer system designed

to perform a specific task. Common examples of embedded systems include MP3

players, navigation systems on aircraft and intruder alarm systems. An embedded

system can also be defined as a single purpose computer.

Most embedded systems are time critical applications meaning that the embedded

system is working in an environment where timing is very important: the results of an

operation are only relevant if they take place in a specific time frame. An autopilot in

an aircraft is a time critical embedded system. If the autopilot detects that the plane

for some reason is going into a stall then it should take steps to correct this within

milliseconds or there would be catastrophic results.

USES OF EMBEDDED SYSTEMS

The uses of embedded systems are virtually limitless, because every day new products

are introduced to the market that utilizes embedded computers in novel ways. In

recent years, hardware such as microprocessors, microcontrollers, and FPGA chipshave become much cheaper. So when implementing a new form of control, it's wiser


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to just buy the generic chip and write your own custom software for it. Producing a

custom-made chip to handle a particular task or set of tasks costs far more time and

money. Many embedded computers even come with extensive libraries, so that

"writing your own software" becomes a very trivial task indeed.

From an implementation viewpoint, there is a major difference between a computer

and an embedded system. Embedded systems are often required to provide Real-Time

response. AReal-Time system is defined as a system whose correctness depends on

the timeliness of its response. Examples of such systems are flight control systems of

an aircraft, sensor systems in nuclear reactors and power plants. For these systems,

delay in response is a fatal error. A more relaxed version ofReal-Time Systems is the

one where timely response with small delays is acceptable. Example of such a system

would be the Scheduling Display System on the railway platforms. In technical

terminology,Real-Time Systems can be classified as:

Hard Real-Time Systems - systems with severe constraints on the timeliness of

the response.

Soft Real-Time Systems - systems which tolerate small variations in response

times.

Hybrid Real-Time Systems - systems which exhibit both hard and soft

constraints on its performance.

Characteristics:

1. Embedded systems are always not stand alone devices. Many embedded

systems consist of small computerized part within a larger device that serves

more general purpose task. For example ABS in automobiles.

2. The program instructions written for embedded systems are referred to as

firmware and are stored in ROM.

Microcontroller

A microcontroller is a small computer on a single circuit containing a

processor core, memory, and programmable input/output peripherals. Program

memory in the form ofnor flash or OTP ROM is also often included on chip,

as well as a typically small amount ofRAM. Microcontrollers are designed for

embedded applications, in contrast to the microprocessors used in personal

computers or other general purpose applications.
http://en.wikipedia.org/wiki/Input/outputhttp://en.wikipedia.org/wiki/Flash_memory#NOR_flashhttp://en.wikipedia.org/wiki/Programmable_read-only_memoryhttp://en.wikipedia.org/wiki/Random-access_memoryhttp://en.wikipedia.org/wiki/Microprocessorhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Microprocessorhttp://en.wikipedia.org/wiki/Random-access_memoryhttp://en.wikipedia.org/wiki/Programmable_read-only_memoryhttp://en.wikipedia.org/wiki/Flash_memory#NOR_flashhttp://en.wikipedia.org/wiki/Input/output


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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 otherembedded 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.

Types:

Some microcontrollers may use four-bit words and operate at clock

rate frequencies as low as 4 kHz, for low power consumption (mill watts or

microwatts). They will generally have the ability to retain functionality while

waiting for an event such as a button press or other interrupt; powerconsumption 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.
http://en.wikipedia.org/wiki/Embedded_systemhttp://en.wikipedia.org/wiki/Mixed-signal_integrated_circuithttp://en.wikipedia.org/wiki/Word_(computer_architecture)http://en.wikipedia.org/wiki/Clock_ratehttp://en.wikipedia.org/wiki/Clock_ratehttp://en.wikipedia.org/wiki/Digital_signal_processorhttp://en.wikipedia.org/wiki/Digital_signal_processorhttp://en.wikipedia.org/wiki/Clock_ratehttp://en.wikipedia.org/wiki/Clock_ratehttp://en.wikipedia.org/wiki/Word_(computer_architecture)http://en.wikipedia.org/wiki/Mixed-signal_integrated_circuithttp://en.wikipedia.org/wiki/Embedded_system


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8051 Microcontroller

Clones which are collectively referred to as the MCS-51 family of microcontrollers,

which includes chips from vendors such as Atmel, Philips, Infineon, and Texas

Instruments.

About the 8051:

The Intel 8051 is an 8-bit microcontroller which means that most available operations

are limited to 8 bits. There are 3 basic "sizes" of the 8051: Short, Standard, and

Extended. The Short and Standard chips are often available in DIP (dual in-line

package) form, but the Extended 8051 models often have a different form factor, and

are not "drop-in compatible". All these things are called 8051 because they can all be

programmed using 8051 assembly language, and they all share certain features

(although the different models all have their own special features).

Some of the features that have made the 8051 popular are:

64 KB on chip program memory.

128 bytes on chip data memory (RAM).

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.

1 Microsecond instruction cycle with 12 MHz Crystal.

8051 models may also have a number of special, model-specific features, such as

UARTs, ADC, Op Amps, etc...


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Typical applications:

8051 chips are used in a wide variety of control systems, telecom applications, and

robotics as well as in the automotive industry. By some estimation, 8051 family chips

make up over 50% of the embedded chip market.

Pin configuration:

PIN 9: PIN 9 is the reset pin which is used reset the microcontrollers internal

registers and ports upon starting up. (Pin should be held high for 2 machine cycles.)

PINS 18 & 19: 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.

PIN 40 and 20: 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.

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 indepth in the later chapters. PIN 29 is called PSEN. This is "program store 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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PORTS:

There are 4 8-bit ports: P0, P1, P2 and P3.

PORT P1 (Pins 1 to 8): The port P1 is a general purpose input/output port which can

be used for a variety of interfacing tasks. The other ports P0, P2 and P3 have dual

roles or additional functions associated with them based upon the context of their

usage.

PORT P3 (Pins 10 to 17): PORT P3 acts as a normal IO port, but Port P3 has

additional functions such as, serial transmit and receive pins, 2 external interrupt pins,

2 external counter inputs, read and write pins for memory access.

PORT P2 (pins 21 to 28): PORT P2 can also be used as a general purpose 8 bit port

when no external memory is present, but if external memory access is required then

PORT P2 will act as an address bus in conjunction with PORT P0 to access external

memory. PORT P2 acts as A8-A15, as can be seen from fig 1.1

PORT P0 (pins 32 to 39): PORT P0 can be used as a general purpose 8 bit port whenno external memory is present, but if external memory access is required then PORT


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P0 acts as a multiplexed address and data bus that can be used to access external

memory in conjunction with PORT P2. P0 acts as AD0-AD7, as can be seen from fig

1.1

Oscillator 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 12MHz clock) to 3.33MHz

(for the maximum 40MHz clock). The oscillator circuit that generates the clock pulses

so that all internal operations are synchronized.


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BLOCK DIAGRAM:


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Program Start Address:

The 8051 starts executing program instructions from address 0000 in the program

memory.

Direct memory:

The 8051 has 256 bytes of internal addressable RAM, although only the first 128

bytes are available for general use by the programmer. The first 128 bytes of RAM

(from 0x00 to 0x7F) are called the Direct Memory, and can be used to store data.

Special function registers:

The Special Function Register (SFR) is the upper area of addressable memory, from

address 0x80 to 0xFF. A, B, PSW, DPTR are called SFR. This area of memory cannot

be used for data or program storage, but is instead a series of memory-mapped ports

and registers. All port input and output can therefore be performed by

memory mov operations on specified addresses in the SFR. Also, different status

registers are mapped into the SFR, for use in checking the status of the 8051, and

changing some operational parameters of the 8051.

General Purpose Registers:

The 8051 has 4 selectable banks of 8 addressable 8-bit registers, R0 to R7. This

means that there are essentially 32 available general purpose registers, although only

8 (one bank) can be directly accessed at a time. To access the other banks, we need to

change the current bank number in the flag status register.

A and B Registers:

The A register is located in the SFR memory location 0xE0. The A register works in a

similar fashion to the AX register of x86 processors. The A register is called

the accumulator, and by default it receives the result of all arithmetic operations. The

B register is used in a similar


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manner, except that it can receive the extended answers from the multiply and divide

operations. When not being used for multiplication and Division, the B register is

available as an extra general-purpose register.

Comparison of 8051 family members:

Feature 8051 8050 8031

ROM 4K 8K 0K

RAM 128K 256K 128K

TIMERS 2 3 2

I/O PORTS 32 32 32

SERIAL PORTS 1 1 1

INTRRUPT SOURCES 6 8 6

Registers:

The vast majority of 8051 registers are of 8-bits.the most widely used registers are:

Accumulator A

B R0

Rr1

R2

R3

R4

R5

R6

R7

Data pointer dptr

Program counter pc


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Accumulator: used for arithmetic and logical instructions .it can hold an 8-bit

value and is most versatile register.

R registers: The R register is a set of 8 registers named from R0 to

R7.these registers are used as auxiliary registers

B Register: The b register is similar to the A registering nsame sense that it can

hold an 8-bit value.

Boolean Instructions

80C51 devices contain a complete Boolean (single-bit) processor. The internal

RAM contains 128 addressable bits, and the SFR space can support up to 128

addressable bits as well. All of the port lines are bit-addressable, and each one

can be treated as a separate single-bit port. The instructions that access these

bits are not just conditional branches, but a complete menu of move, set, clear,

complement, OR, and AND instructions. These kinds of bit operations are noteasily obtained in other architectures with any amount of byte-oriented

software.

Bit addresses 00H through 7FH are in the Lower 128, and bit addresses 80H

through FFH are in SFR space.

Note how easily an internal flag can be moved to a port pin:

MOV C,FLAG


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MOV P1.0,C

In this example, FLAG is the name of any addressable bit in the Lower 128 or

SFR space. An I/O line (the LSB of Port 1, in this case) is set or cleared

depending on whether the flag bit is 1 or 0.

The Carry bit in the PSW is used as the single-bit Accumulator of the Boolean

processor. Bit instructions that refer to the Carry bit as C assemble as Carry-

specific instructions (CLR C, etc.). The Carry bit also has a direct address,

since it resides in the PSW register, which is bit-addressable.

Note that the Boolean instruction set includes ANL and ORL operations, but

not the XRL (Exclusive OR) operation. An XRL operation is simple to

implement in software. Suppose, for example, it is required to form the

Exclusive OR of two bits: C = bit1 .XRL. bit2

The software to do that could be as follows:

MOV C,bit1

JNB bit2,OVER

CPL C

OVER: (continue)

First, bit1 is moved to the Carry. If bit2 = 0, then C now contains the correct

result. That is, bit1 .XRL. bit2 = bit1 if bit2 = 0. On the other hand, if bit2 = 1,

C now contains the complement of the correct

result. It need only be inverted (CPL C) to complete the operation.

This code uses the JNB instruction, one of a series of bit-test instructions

which execute a jump if the addressed bit is set (JC, JB, JBC) or if the

addressed bit is not set (JNC, JNB). In the above case, bit2 is being tested, and

if bit2 = 0, the CPL C instruction is jumped over.

JBC executes the jump if the addressed bit is set, and also clears the bit. Thus

a flag can be tested and cleared in one operation. All the PSW bits are directlyaddressable, so the Parity bit, or the


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general purpose flags, for example, are also available to the bit-test

instructions.

Relative Offset

The destination address for these jumps is specified to the assembler by a label

or by an actual address in Program memory.

However, the destination address assembles to a relative offset byte. This is a

signed (twos complement) offset byte which is added to the PC in twos

complement arithmetic if the jump is executed.

The range of the jump is therefore 128 to +127 Program Memory bytes

relative to the first byte following the instruction.

Jump Instructions.

The three SJMP, LJMP, and AJMP, are differ in the format of the destination

address. JMP is a generic mnemonic which can be used if the programmer

does not care which way the jump is encoded.

The SJMP instruction encodes the destination address as a relative offset, as

described above. The instruction is 2 bytes long, consisting of the opcode and

the relative offset byte. The jump

distance is limited to a range of128 to +127 bytes relative to the instruction

following the SJMP.

The LJMP instruction encodes the destination address as a 16-bit constant.

The instruction is 3 bytes long, consisting of the opcode and two address

bytes. The destination address can be anywhere in the 64k Program Memory

space.

The AJMP instruction encodes the destination address as an 11-bitconstant.

The instruction is 2 bytes long, consisting of the opcode, which itself contains


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3 of the 11 address bits, followed by another byte containing the low 8 bits of

the destination address. When the instruction is executed, these 11 bits are

simply substituted for the low 11 bits in the PC. The high 5 bits stay the same.

Hence the destination has to be within the same 2k block as the instruction

following the AJMP. assembler in the same way: as a label or as a 16-bit

constant. The assembler will put the destination address into the correct format

for the given instruction. If the format required by the instruction will not

support the distance to the specified destination address, a Destination out of

range message is written into the List file.

The JMP @A+DPTR instruction supports case jumps. The destination address

is computed at execution time as the sum of the 16-bit DPTR register and the

Accumulator. Typically, DPTR is set up with the address of a jump table. In a

5-way branch, for example, an integer 0 through 4 is loaded into the

Accumulator. The code to be executed might be as follows:

MOV DPTR,#JUMP TABLE

MOV A,INDEX_NUMBER

RL A

JMP @A+DPTR

The RL A instruction converts the index number (0 through 4) to an even

number on the range 0 through 8, because each entry in the jump table is 2

bytes long:

JUMP TABLE:

AJMP CASE 0

AJMP CASE 1

AJMP CASE 2

AJMP CASE 3

AJMP CASE 4


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There are two call statements LCALL and ACALL, which differ in the format

in which thesubroutine address is given to the CPU. CALL is a generic

mnemonic which can be used if the programmer does not care which way the

address is encoded.

The LCALL instruction uses the 16-bit address format, and the subroutine can

be anywhere in the 64k Program Memory space. The ACALL instruction uses

the 11-bit format, and the subroutine must be in the same 2k block as the

instruction following the ACALL.

In any case, the programmer specifies the subroutine address to the assembler

in the same way: as a label or as a 16-bit constant. The assembler will put the

address into the correct format for the given instructions.

Subroutines should end with a RET instruction, which returns execution to the

instruction following the CALL.

RETI is used to return from an interrupt service routine. The only difference

between RET and RETI is that RETI tells the interrupt control system that the

interrupt in progress is done. If there is no interrupt in progress at the time

RETI is executed, then the RETI is functionally identical to RET.

All of these jumps specify the destination address by therelative offset

method, and so are limited to a jump distance of128to +127 bytes from the

instruction following the conditional jump instruction. Important to note,

however, the user specifies to the assembler the actual destination address the

same way as the other jumps: as a label or a 16-bit constant.

There is no Zero bit in the PSW. The JZ and JNZ instructions test the

Accumulator data for that condition.

The DJNZ instruction (Decrement and Jump if Not Zero) is for loop control.

To execute a loop N times, load a counter byte with N and terminate the loop

with a DJNZ to the beginning of the loop, as shown below for N = 10.

MOV LOOP: (begin loop) COUNTER,#10


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(end loop)

DJNZ(continue) COUNTER,LOOP

The CJNE instruction (Compare and Jump if Not Equal) can also be used for

loop control as in Figure 12. Two bytes are specified in the operand field of

the instruction. The jump is executed only if the two

bytes are not equal. The two bytes were data in R1 and the constant 2AH. The

initial data in R1 was 2EH. Every time the loop was executed, R1 was

decremented, and the looping was to continue until the R1 data reached 2AH.

Another application of this instruction is in greater than, less than

comparisons. The two bytes in the operand field are taken as unsigned

integers. If the first is less than the second, then the Carry bit is set (1). If the

first is greater than or equal to the second, then the Carry bit is cleared.

CPU Timing

All 80C51 microcontrollers have an on-chip oscillator which can be used if

desired as the clock source for the CPU. To use the on-chip oscillator, connect

a crystal or ceramic resonator between the XTAL1 and XTAL2 pins of the

microcontroller, and capacitors to ground.

Machine Cycles

A machine cycle consists of a sequence of 6 states, numbered S1 through S6.

Each state time lasts for two oscillator periods. Thus a machine cycle takes 12


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oscillator periods or 1s if the oscillator frequency is 12MHz.

Each state is divided into a Phase 1 half and a Phase 2 half . Normally two

program fetches are generated during each machine cycle, even if the

instruction being executed doesnt require it. If the instruction being executed

doesnt need more code bytes, the CPU simply ignores the extra fetch, and the

Program Counter is not incremented.

Execution of a one-cycle instruction (Figures 15a and 15b) begins during State

1 of the machine cycle, when the opcode is latched into the Instruction

Register. A second fetch occurs during S4 of the same machine cycle.

Execution is complete at the end of State 6 of this machine cycle.

The MOVX instructions take two machine cycles to execute. No program

fetch is generated during the second cycle of a MOVX instruction. This is the

only time program fetches are skipped.

The fetch/execute sequences are the same whether the Program Memory is

internal or external to the chip. Execution times do not depend on whether the

Program Memory is internal or external.

If Program Memory is external, then the Program Memory read strobe PSEN

is normally activated twice per machine cycle. If an access to external Data

Memory occurs, two PSENs are skipped, because the address and data bus are

being used for the Data Memory access.

Note that a Data Memory bus cycle takes twice as much time as a Program

Memory bus cycle. Figure 16 shows the relative timing of the addresses being

emitted at Ports 0 and 2, and of ALE and PSEN. ALE is used to latch the low

address byte from P0 into the address latch.

When the CPU is executing from internal Program Memory, PSEN is not activated,

and program addresses are not emitted. However, ALE continues to be activated

twice per machine cycle and so it is available as a clock output signal. Note, however,

that one ALE is skipped during the execution of the MOVX instruction.

Serial communication

Beside stated above we've added to the already existing unit the possibility of

communication with an outside world. However, this way of communicating has its

drawbacks. One of the basic drawbacks is the number of lines which need to be used

in order to transfer data. What if it is being transferred to a distance of several

kilometers? The number of lines times number of kilometers doesn't promise the

economy of the project. It leaves us having to reduce the number of lines in such a


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way that we don't lessen its functionality. Suppose we are working with three lines

only, and that one line is used for sending data, other for receiving, and the third one

is used as a reference line for both the input and the output side. In order for this to

work, we need to set the rules of exchange of data. These rules are called protocol.

Protocol is therefore defined in advance so there wouldn't be any misunderstanding

between the sides that are communicating with each other. For example, if one man is

speaking in French, and the other in English, it is highly unlikely that they will

quickly and effectively understand each other. Let's suppose we have the following

protocol. The logical unit "1" is set up on the transmitting line until transfer begins.

Once the transfer starts , we lower the transmission line to logical "0" for a period of

time (which we will designate as T), so the receiving side will know that it is

receiving data, and so it will activate its mechanism for reception. Let's go back now

to the transmission side and start putting logic zeros and ones onto the transmitter line

in the order from a bit of the lowest value to a bit of the highest value. Let each bit

stay on line for a time period which is equal to T, and in the end, or after the 8th bit,

let us bring the logical unit "1" back on the line which will mark the end of the

transmission of one data. The protocol we've just described is called in professional

literature NRZ (Non-Return to Zero).

LCD INTERFACING

These LCD screens are limited to text only and are often used in copiers, fax

machines, laser printers, industrial test equipment, networking equipment such as

routers and storage devices.

Character LCDs can come with or without backlights, which may be LED,

fluorescent, or electroluminescent.

Character LCDs use a standard 14-pin interface and those with backlights have 16

pins. The pinouts are as follows:

1. Ground

2. VCC (+3.3 to +5V)


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3. Contrast adjustment (VO)

4. Register Select (RS). RS=0: Command, RS=1: Data

5. Read/Write (R/W). R/W=0: Write, R/W=1: Read

6. Clock (Enable). Falling edge triggered

7. Bit 0 (Not used in 4-bit operation)



10.Bit 3 (Not used in 4-bit operation)

11.Bit 4

12.Bit 5

13.Bit 6

14.Bit 7

15.Backlight Anode (+)

16.Backlight Cathode (-)

There may also be a single backlight pin, with the other connection via Ground or

VCC pin. The two backlight pins may precede the pin 1.

The nominal backlight voltage is around 4.2V at 25C using a VDD 5V capable

model.

Character LCDs can operate in 4-bit or 8-bit mode. In 4 bit mode, pins 7 through 10

are unused and the entire byte is sent to the screen using pins 11 through 14 by

sending 4-bits (nibble) at a time.

3- >VARISTOR

4-> RS

5-> RW

6-> EN

7-14-> DATA LINE INPUTS


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LCD Command Codes:

CODE COMMAND TO LCD

1 Clear display screen

2 Return home

4 Shift cursor to left

6 Shift cursor to right

5 Shift display right

7 Shift display left

8 Display off, cursor off

A Display off, cursor on

C Display on, cursor off

E Display on, cursor blinking

F Display on, cursor blinking

10 Shift cursor position to left

14 Shift cursor position to right

18 Shift entire display to left

1C Shift entire display to right

80 Force cursor to beginning of 1st

line

C0 Force cursor to beginning of 2nd line

38 2 lines and 5x7 matrix


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INTERFACING OF SEVEN SEGMENT WITH

MICROCONTROLLER

Seven segment display is been connected to port0 of the micro controller with a series

resistance of 330 ohms.

To enable a particular digit, the corresponding bit of the microcontroller is

made low.

Pin 40,31,9 are connected with the supply voltage.

Pin 20 is been grounded.

At Pin 18 and 19 crystal oscillator is provided for the clock pulse.


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Keypad

A keypad is a set of buttons arranged in a block or "pad" which usually bear

digits, symbols and usually a complete set of alphabetical letters. If it mostly

contains numbers then it can also be called a numeric keypad. Keypads are

found on many alphanumeric keyboards and on other devices such as

calculators, push-button telephones, combination locks, and digital door locks,

which require mainly numeric input. The key are arranged in form of mesh

where each key is connected to 1 row and 1 columns and the rows and

columns are connected to the port of microcontroller


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EXPERT TALK:

Mr. Pramod from Ericson

o He discussed about different types of sensors used in the industry.

Starting with temperature sensor and extending his views with

hydraulic sensors, closed and automation sensors.

o The basic theme behind the session was project management.

Mr. Bhupesh from L and T

o He discussed about different parts of an operating system. He gave

away his views on topics like kernel, microkernel etc. another topics of

interest was cloud computing, memory management, cache memory

etc.

Mrs. Manpreet kapur from G.T.B.I.T.

o She discussed about various corporate etiquettes, difference between a

good and bad interview, different types of handshakes, organisational

behaviour, proper way of dressing for an interview, various interview

questions are also been discussed.

Mr. Tapan from L AND T

o He gave away his views on ARM processor, how ARM processor

forms a fundamental part of approximately every electronic gadget. He

also discussed about ARM nomenclature, pipeline organisation,

difference between CISC and RISC, operating modes of ARM

processor etc.

Mrs. Jasdeep Kaur from G.T.B.I.T.

o She discussed about Very Large Scale Integrated Circuits. The aim of

the session is to encourage designers to design the circuits which are

capable of operating at a LOW voltage (less than 3V).

o Various hardware designing techniques like difference between

cascade and cascade, advantages of CMOS transistors over BJTtransistors were also discussed.


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INDUSTRIAL VISITS:

LOK SABHA T.V.

o Industrial visit to lok sabha T.V. has been organised.

o Various transmission devices are shown like:

High definition camera.

Standard definition camera.

Master switcher.

o Production control room and master control room were also shown.

o Discussion about delay we receive in case of LIVE telecast due to

uplink and downlinking of the signal through satellites,towers etc.

o Different recording studios were also shown.

INDERPRASTHA GAS LIMITED

o Industrial visit to Inderprastha Gas Limited(IGL).

o Discussion on various unit of power and energy like MW,KW,KWH

etc.

o Procedure to generate electricity from gas and using the by product of

gas to again

generate electricity is also discussed.

o Plant visit includes introduction to:-

1) Boilers

2) Filters

3) Controllers

4) Relays

5) Turbine

6) Compressor

7) Tempertature sensor

8) Transformers

9) Transformer lines

10)Starter

o Master control room is also been shown which includes back up

system,emergency switch.


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Practicals done in training

Practical no 1st:

Aim: soldering and desoldering

The most fundamental skill needed to assemble any electronic project is that of

soldering. It takes some practice to make the perfect joint, but, like riding a bicycle,

once learned is never forgotten! The idea is simple: to join electrical parts together to

form an electrical connection, using a molten mixture of lead and tin (solder*) with a

soldering iron. A large range of soldering irons is available - which one is suitable for

you depends on your budget and how serious your interest in electronics is.

Voltage: most irons run from the mains at 240V. However, low voltage types (e.g.

12V or 24V) generally form part of a "soldering station" and are designed to be used

with a special controller made by the same manufacturer.

Wattage: Typically, they may have a power rating of between 15-25 watts or so,

which is fine for most work. A higher wattage does not mean that the iron runs hotter

- it simply means that there is more power in reserve for coping with larger joints.

This also depends partly on the design of the "bit" (the tip of the iron). Consider a

higher wattage iron simply as being more "unstoppable" when it comes to heavier-

duty work, because it won't cool down so quickly.

Temperature Control: the simplest and cheapest types don't have any form of

temperature regulation. Simply plug them in and switch them on! Thermal regulation

is "designed in" (by physics, not electronics!): they may be described as "thermally

balanced" so that they have some degree of temperature "matching" but their output

will otherwise not be controlled. Unregulated irons form an ideal general purpose iron

for most users, and they generally cope well with printed circuit board soldering andgeneral interwiring.

Bits: it's useful to have a small selection of manufacturer's bits (soldering iron tips)

available with different diameters or shapes, which can be changed depending on the

type of work in hand. You'll probably find that you become accustomed to, and work

best with, a particular shape of tip. Often, tips are iron-coatedto preserve their life, or

they may be bright-plated instead. Copper tips are seldom seen these days.


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Spare parts: it's nice to know that spare parts may be available, so if the element

blows, you don't need to replace the entire iron. This is especially so with expensive

irons.

You will occasionally see gas-poweredsoldering irons which use butane rather than

the mains electrical supply to operate. They have a catalytic element which, once

warmed up, continues to glow hot when gas passes over them. Service engineers use

them for working on repairs where there may be no power available, or where a joint

is tricky to reach with a normal iron, so they are really for occasional "on the spot"

use for quick repairs, rather than for mainstream construction or assembly work

How to make the perfect solder joint

All parts must be clean and free from dirt and grease.

Try to secure the work firmly.

"Tin" the iron tip with a small amount of solder. Do this immediately, with

new tips being used for the first time.

Clean the tip of the hot soldering iron on a damp sponge.

Many people then add a tiny amount of fresh solder to the cleansed tip.

Heat all parts of the joint with the iron for under a second or so.

Continue heating, then apply sufficient solder only, to form an adequate joint.

Remove and return the iron safely to its stand.

It only takes two or three seconds at most, to solder the average p.c.b. joint.

Do not move parts until the solder has cooled.

Desoldering methods

A soldered joint which is improperly made will be electrically "noisy", unreliable and

is likely to get worse in time. It may even not have made any electrical connection at

all, or could work initially and then cause the equipment to fail at a later date! It can

be hard to judge the quality of a solder joint purely by appearances, because you

cannot say how the joint actually formed on the inside, but by following the

guidelines there is no reason why you should not obtain perfect results.


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A joint which is poorly formed is often called a "dry joint". Usually it results from dirt

or grease preventing the solder from melting onto the parts properly, and is often

noticeable because of the tendency of the solder not to "spread" but to form beads or

globules instead, perhaps partially. Alternatively, if it seems to take an inordinately

long time for the solder to spread, this is another sign of possible dirt and that the joint

may potentially be a dry one.

There will undoubtedly come a time when you need to remove the solder from a joint:

possibly to replace a faulty component or fix a dry joint. The usual way is to use a

desoldering pumpor vacuum pump which works like a small spring-loaded bicycle

pump, only in reverse! (More demanding users using CMOS devices might need a

pump which is ESD safe.) A spring-loaded plunger is released at the push of a button

and the molten solder is then drawn up into the pump. It may take one or two attempts

to clean up a joint this way, but a small desoldering pump is an invaluable tool

especially for p.c.b. work.

Sometimes, it's effective to actually add more solder and then desolder the whole lotwith a pump, if the solder is particularly awkward to remove. Care is needed, though,

to ensure that the boards and parts are not damaged by excessive heat; the pumps

themselves have a P.T.F.E. nozzle which is heat proof but may need replacing

occasionally.

An excellent alternative to a pump is to use desoldering braid, including the famous

American "Soder-Wick" (sic) or Adcola "TISA-Wick" which are packaged in small

dispenser reels. This product is a specially treated fine copper braid which draws

molten solder up into the braid where it solidifies. The best way is to use the tip of the

hot iron to press a short length of braid down onto the joint to be de-soldered. The

iron will subsequently melt the solder, which will be drawn up into the braid. Take

extreme care to ensure that you don't allow the solder to cool with the braid adhering

to the work, or you run the risk of damaging p.c.b. copper tracks when you attempt to

pull the braid off the joint. See my photo gallery for more details.

I recommend buying a small reel of de-soldering braid, especially for larger or

difficult joints which would take several attempts with a pump. It is surprisingly

effective, especially on difficult joints where a desoldering pump may prove a

struggle.

First Aid

If you are unlucky enough to receive burns which require treatment, here's what to do

:-

1. Immediately cool the affected area with cold running water for several

minutes.

2. Remove any rings etc. before swelling starts.

3. Apply a sterile dressing to protect against infection.

4. Do not apply lotions, ointments etc., nor prick any blisters which form later.

5. Seek professional medical advice where necessary.


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Practical no 2nd

:

Aim: write your name with the help of ribbon wires on pcb

in this experiment we use ribbon wire , soldering wire, soldering iron and a general

purpose pcb, in which we solder ribbion wire on pcb for making our name on it, itwill enhance our soldering practice and make it perfect.

Practical no 3rd

:

Aim: Solder an IC base on pcb

In this experiment we use a 16 pin ic base, soldering wire, soldering iron and a pcb.

First we mount a ic base on a pcb and solder its legs without any short between the

legs.

Practical no 4th

:

Aim: Joining the legs of one ic base with other ic base

In this experiment we use two 16 pin ic bases, soldering wire, soldering iron and a

general purpose pcb. In this experiment we join even of one base to odd of another ic

base by using connecting wires, and make sure no to pins can be short.

Practical no 5th

:

Aim: drive an dc motor with the help of IC L293D

In this experiment we use dc motor, soldering wire, soldering iron, IC L293D,

regulated power supply. For this experiment first we have make a power supply of

regulated 5 V, after that we solder a 16 pin IC base on a pcb and make sure no two

pins of base where short.

L293D is a dual H-bridge motor driver integrated circuit (IC). Motor drivers act as

current amplifiers since they take a low-current control signal and provide a higher-

current signal. This higher current signal is used to drive the motors.

L293D contains two inbuilt H-bridge driver circuits. In its common mode of

operation, two DC motors can be driven simultaneously, both in forward and reverse

direction. The motor operations of two motors can be controlled by input logic at pins

2 & 7 and 10 & 15. Input logic 00 or 11 will stop the corresponding motor. Logic 01

and 10 will rotate it in clockwise and anticlockwise directions, respectively.

Enable pins 1 and 9 (corresponding to the two motors) must be high for motors to

start operating. When an enable input is high, the associated driver gets enabled. As a

result, the outputs become active and work in phase with their inputs. Similarly, when
http://www.engineersgarage.com/electronic-circuits/h-bridge-motor-controlhttp://www.engineersgarage.com/electronic-circuits/h-bridge-motor-control


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the enable input is low, that driver is disabled, and their outputs are off and in the

high-impedance state.

Pin Description:

Pin

NoFunction Name

1 Enable pin for Motor 1; active high Enable 1,2

2 Input 1 for Motor 1 Input 1

3 Output 1 for Motor 1 Output 1

4 Ground (0V) Ground




8 Supply voltage for Motors; 9-12V (up to 36V) Vcc 29 Enable pin for Motor 2; active high Enable 3,4






15 Input2 for Motor 1 Input 4

16 Supply voltage; 5V (up to 36V) Vcc 1


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Practical no 6th

:

Aim: glowing an LED using LDR

In this experiment we use an LED, LDR, IC LMB24, IC 40106, resistances, regulated

power supply. Soldering iron, soldering wire. In this experiment we introduce theconcept of pull up and pull down resistance, in this experiment we use pull down

resistance with the LDR.

Practical no 7th

:

Aim: working of a relay with transistor and IC ULN2003

In this experiment we use relay, transistor BC 557, IC ULN2003, regulated power

supply, key, resistances, LED, etc.

Circuit diagram for a relay with a transistor is:


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Circuit diagram for a relay and an IC ULN2003

Description of the project:

Introduction:

Protect our family and valuables with this microcontroller based security system

knowing that should anyone trying to break into our home, an alarm will go ON and

the police will be alerted immediately.

The microcontroller based security system consists of transmitter, receiver, phase

locked loop and processing section. The transmitter section continuously transmits IR

rays which are received by the receiver section. The received signal is further

amplified and given to the PLL section, where its frequency is locked to the

transmitted frequency. The transmitter and receiver are arranged such that the

transmitted IR rays fall directly onto the photodiode the receiver.


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Diagram shown above is a block diagram of microcontroller based security system, in

this for transmitting section we use ir sensor and for receiving we use photo diodes,

when there is interrupt between ir rays, it give its response to the microcontroller and

according to microcontroller programming it work further and the alarms starts.


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Circuit diagram:


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COMPONENTS DISCRIPTION

Microcontroller P89V51:

80C51 Central Processing Unit

5 V Operating voltage from 0 MHz to 40 MHz

16/32/64 kB of on-chip Flash user code memory with ISP (In-System

Programming) and IAP (In-Application Programming)

Four 8-bit I/O ports with three high-current Port 1 pins (16 mA each)

Photo diode:

Features

PIN photodiode

Package type: T-1 3/4 (5mm lens diameter)

Wide reception angle, 40

Daylight filter

Package material and color: black epoxy

High sensitivity

Peak sensitivity= 880nm

Radiant sensitive area: 1.245mm x 1.245mm


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Absolute Maximum Ratings

(TA= 25C unless otherwise specified)

Stresses exceeding the absolute maximum ratings may damage the device. The device

may not function or beoperable above the recommended operating conditions and stressing the parts to these

levels is not recommended.

In addition, extended exposure to stresses above the recommended operating

conditions may affect device reliability.

The absolute maximum ratings are stress ratings only

Ir LEDs:

Infrared (IR) light is electromagnetic radiation with a wavelength longer than that of

visible light, measured from the nominal edge of visible red light at 0.74 micrometers,

and extending conventionally to 300 micrometers. These wavelengths correspond to a

frequency range of approximately 1 to 400 THz,[1]

and include most of the thermal

radiation emitted by objects near room temperature. Microscopically, IR light is

typically emitted or absorbed by molecules when they change their rotational-

vibration movements.

Its appropriate operating voltage is around 1.4v.

The current is generally smaller than 20mA.

It emits IR rays which receive by photodiode in our project.
http://en.wikipedia.org/wiki/Electromagnetic_radiationhttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Visible_lighthttp://en.wikipedia.org/wiki/Redhttp://en.wikipedia.org/wiki/Micrometerhttp://en.wikipedia.org/wiki/Micrometrehttp://en.wikipedia.org/wiki/THzhttp://en.wikipedia.org/wiki/Infrared#cite_note-0http://en.wikipedia.org/wiki/Infrared#cite_note-0http://en.wikipedia.org/wiki/Infrared#cite_note-0http://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Infrared_spectroscopyhttp://en.wikipedia.org/wiki/Infrared_spectroscopyhttp://en.wikipedia.org/wiki/Infrared_spectroscopyhttp://en.wikipedia.org/wiki/Infrared_spectroscopyhttp://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Infrared#cite_note-0http://en.wikipedia.org/wiki/THzhttp://en.wikipedia.org/wiki/Micrometrehttp://en.wikipedia.org/wiki/Micrometerhttp://en.wikipedia.org/wiki/Redhttp://en.wikipedia.org/wiki/Visible_lighthttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Electromagnetic_radiation


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Power Supply:

There are many types of power supply. Most are designed to convert high voltage AC

mains electricity to a suitable low voltage supply for electronic circuits and otherdevices. A power supply can by broken down into a series of blocks, each of which

performs a particular function.

For example a 5V regulated supply:

Each of the blocks is described in more detail below:

Transformer - steps down high voltage AC mains to low voltage AC.


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Rectifier - converts AC to DC, but the DC output is varying.

Smoothing - smooths the DC from varying greatly to a small ripple.

Regulator - eliminates ripple by setting DC output to a fixed voltage.

Power supplies made from these blocks are described below with a circuit diagram

and a graph of their output:

Transformer only

Transformer + Rectifier

Transformer + Rectifier + Smoothing

Transformer + Rectifier + Smoothing + Regulator

Transformer only

The low voltage AC output is suitable for lamps, heaters and special AC motors. It is

not suitable for electronic circuits unless they include a rectifier and a smoothing

capacitor


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Transformer + Rectifier

The varying DC output is suitable for lamps, heaters and standard motors. It is not

suitable for electronic circuits unless they include a smoothing capacitor.

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 voltage, step-down transformers reduce voltage. Most

power supplies use a step-down transformer to reduce the dangerously high mains

voltage (230V in UK) 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 the 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.


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Transformer

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.

Step-up transformers increase voltage, step-down transformers reduce voltage. Most

power supplies use a step-down transformer to reduce the dangerously high mains

voltage (230V in UK) 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 the 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 turns ratio, determines theratio of the voltages. A step-down transformer has a large number 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.

turns ratio =Vp

=Np

andpower out = power in

Vs Ns Vs Is = Vp Ip

Vp = primary (input) voltage

Np = number of turns on primary coil

Ip = primary (input) current

Vs = secondary (output) voltage

Ns = number of turns on secondary coil

Is = secondary (output) current


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Rectifier

There are several ways of connecting diodes to make a rectifier to convert AC to DC.

The bridge rectifier is the most important and it produces full-wave varying DC. A

full-wave rectifier can also be made from just two diodes if a centre-tap transformer is

used, but this method is rarely used now that diodes are cheaper. A single diode can

be used as a rectifier but it only uses the positive (+) parts of the AC wave to produce

half-wave varying DC.

Bridge rectifier

A bridge rectifier can be made using four individual diodes, but it is also available in

special packages containing the four diodes required. It is called a full-wave rectifier

because it uses all the AC wave (both positive and negative sections). 1.4V is used up

in the bridge rectifier because each diode uses 0.7V when conducting and there are

always two diodes conducting, as shown in the diagram below. Bridge rectifiers are

rated by the maximum current they can pass and the maximum reverse voltage they

can withstand (this must be at least three times the supply RMS voltage so the

rectifier can withstand the peak voltages). Please see the Diodes page for more

details, including pictures of bridge rectifiers.


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Smoothing

Smoothing is performed by a large value electrolytic capacitor connected across theDC supply to act as a reservoir, supplying current to the output when the varying DC

voltage from the rectifier is falling. The diagram shows the unsmoothed varying DC

(dotted line) and the smoothed DC (solid line). The capacitor charges quickly near the

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

Note that smoothing significantly increases the average DC voltage to almost the

peak value (1.4 RMS value). For example 6V RMS AC is rectified to full wave DC

of about 4.6V RMS (1.4V is lost in the bridge rectifier), with smoothing this increases

to almost the peak value giving 1.4 4.6 = 6.4V smooth DC.

Smoothing is not perfect due to the capacitor voltage falling a little as it discharges,

giving a small ripple voltage. For many circuits a ripple which is 10% of the supply

voltage is satisfactory and the equation below gives the required value for the

smoothing capacitor. A larger capacitor will give less ripple. The capacitor valuemust be doubled when smoothing half-wave DC.

Smoothing capacitor for 10% ripple, C =5 Io

Vs f

C =smoothing capacitance in farads (F)

Io = output current from the supply in amps (A)

Vs = supply voltage in volts (V), this is the peak value of the unsmoothed DC

f = frequency of the AC supply in hertz (Hz), 50Hz in the UK


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Regulator

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

output voltages. They are also rated by the maximum current they can pass. 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 regulator ICs have 3 leads and look like power transistors,

such as the 7805 +5V 1A regulator shown on the right. They include a hole for

attaching a heatsink if necessary.

Zener diode regulator

For low current power supplies a simple voltage regulator can be made with a resistor

and a zener diode connected in reverse as shown in the diagram. Zener diodes are

rated by their breakdown voltage Vz and maximum power Pz (typically 400mW or

1.3W).

The resistor limits the current (like an LED resistor). The current through the resistoris constant, so when there is no output current all the current flows through the zener

diode and its power rating Pz must be large enough to withstand this.

Choosing a zener diode and resistor:

The zener voltage Vz is the output voltage required

The input voltage Vs must be a few volts greater than Vz

(this is to allow for small fluctuations in Vs due to ripple)

The maximum current Imax is the output current required plus 10%

The zener power Pz is determined by the maximum current: Pz > Vz Imax

The resistor resistance: R = (Vs - Vz) / Imax

The resistor power rating: P > (Vs - Vz) Imax


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IC LM324:

IC LM324 consists of 4 comparator circuits.

A comparator is a circuit which is used to compare voltage applied at 1

terminal with the reference voltage at another terminal.

When Vin < Vref ; Output will be LOW.(0V)

When Vin > Vref ; Output will be HIGH.(3.83V)

Vin = 2.67V (without vehicle).

Vin = 3.83V (with vehicle).

Vref = 3.2V

Whenever Vin > Vref, the output of the comparator goes HIGH (3.9V) else it

will remain LOW (0V).


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IC 40106:

The HEF40106B provides six inverting buffers. Each input has a Schmitt trigger

circuit. The inverting buffer switches at different points for positive-going and

negative-going signals. The difference between the positive voltage (VT+) and the

negative voltage (VT) is defined as hysteresis voltage (VH). The HEF40106B may

be used for enhanced noise immunity or to square up slowly changing waveforms.

It operates over a recommended VDD power supply range of 3 V to 15 V referenced

to VSS (usually ground). Unused inputs must be connected to VDD, VSS, or another

input. It is also suitable for use over both the industrial (40 C to +85 C) and

automotive (40 C to +125 C) temperature ranges.

Features and benefits

1. Schmitt trigger input discrimination

2. Fully static operation

3. 5 V, 10 V, and 15 V parametric ratings

4. Standardized symmetrical output characteristics

5. Operates across the automotive temperature range from 40 C to +125 C

6. Complies with JEDEC standard JESD 13-B

Applications:

1. Wave and pulse shapers

2. Astable multivibrators

3. Monostable multivibrators


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[60]

IC L293D:

Description:

The L293 and L293D are quadruple high-current half-H drivers. The L293 is

designed to provide bidirectional drive currents of up to 1 A at voltages from 4.5 V to

36 V. The L293D is designed to

provide bidirectional drive currents of up to 600-mA at voltages from 4.5 V to 36 V.

Both devices are designed to drive inductive loads such as relays, solenoids, dc and

bipolar stepping motors, as well as other high-current/high-voltage loads in positive-

supply applications. All inputs are TTL compatible. Each output is a complete totem-

pole drive circuit, with a Darlington transistor sink and a pseudo-Darlington source.

Drivers are enabled in pairs, with drivers 1 and 2 enabled by 1,2EN and drivers 3 and

4 enabled by 3,4EN. When an enable input is high, the associated drivers are enabled

and their outputs are active and in phase with their inputs. When the enable input is

low, those drivers are disabled and

their outputs are off and in the high-impedance state. With the proper data inputs,

each pair of drivers forms a full-H (or bridge) reversible drive suitable for solenoid ormotor applications. On the L293, external high-speed output clamp diodes should be

used for inductive transient suppression. A VCC1 terminal, separate from VCC2, is

provided for the logic inputs to minimize device power dissipation. The L293and


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WORKING

Whenever an interrupt came in between the IR led and photo diode, voltage

across IR led increases to 1.5V.

This 1.5 volt becomes input to the IC LM324 which is comparator with

reference voltage 1V.

As input increases to more than 1V then its output becomes 3.8V.

This is fed into Schmitt trigger 40106(CMOS) as input and gave output

exactly 0V.

This Schmitt trigger output is connected to pin 14 of microcontroller P89V51.

According to our programming when we get 0 on pin 14 of microcontroller,

its start working.

On pin no 1 and 2 of microcontroller we connect IC L293D, which will help

in driving the motor and the door locked.

And also buzzer start buzzing and leds glow which is connected on port P2

of microcontroller.


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FUTURE SCOPE

Our project can be interfaced with the LCD to display the message.

It can be interfaced with the computer and sends the message to user if any

unauthorized person wants to enter home.

We can add a more sensors like wire loop sensor, magnetic sensor, fire sensor.

It can sense when there is a fire in the home.

We can use laser in place of photo diode an ir sensor to make it more efficient.

It can be use for military purpose.


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CONCLUSION

An automated home can be a very simple grouping of controls, or it can be heavily

automated where any appliance that is plugged into electrical power is remotely

controlled. Costs mainly include equipment, components, furniture, and custom

installation.

Ongoing costs include electricity to run the control systems, maintenance costs for the

control and networking systems, including troubleshooting, and eventual cost of

upgrading as standards change. Increased complexity may also increase maintenancecosts for networked devices. Learning to use a complex system effectively may take

significant time and training.

Control system security may be difficult and costly to maintain, especially if the

control system extends beyond the home, for instance by wireless or by connection to

the internet or other networks.

The Microcontroller will continuously monitors all the Sensors and if it found any

security problem then the Microcontroller will switch on the Alarm until the Reset

button was Pressed.


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APPENDIX

FIG. NO. DESCRIPTION PAGE NO.

1 VARIABLE RESISTOR 10

2 ELECTROLYTIC CAPACITOR 11

3 CERAMIC CAPACITOR 12

4 SMOOTHING OF WAVEFORM 14

5 HALF WAVE RECTIFIER 15

6 FULL WAVE RECTIFIER 16

7 BRIDGE RECTIFIER 16

8 VOLTAGE REGULATOR 17

9 L.D.R. 18

10 SEVEN SEGMENT DISPLAY 19

11 COMMON ANODE, COMMON CATHODE 19

12 TRANSISTOR AS A SWITCH 20

13 ADDRESS BUS OF 8051 21

14 MICROPROCESSOR 22

15 MICROCONTROLLER 23

16 8-BIT REGISTER 25

17 PIN DIAGRAM OF 8051 27

18 CRYSTAL OSCILLATOR 28

19 POWER ON RESET CIRCUIT 28

20 OPEN DRAIN 30

21 MEMORY MAPPING 30

22 REGISTER BANK 31

23 STACK 31

24 INTERFACING OF LED WITH MIC 35

25 INTERFACING OF SEVEN SEGMENT WITH MIC 36

26 INTERFACING OF LCD WITH MIC 37

27 POWER SUPPLY 52

28 TRANSFORMER 53


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29 DIODES 53

30 CAPACITOR 53

31 RESISTANCE AND LED 54

32 IR LED 55

33 PHOTODIODE 56

34 PHOTODIODE 57

35 OPTOCOUPLER 58

36 IC LM324 59

37 IC 40106 61

38 PIN DIAGRAM OF 8051 6439 CRYSTAL OSCILLATOR 65

40 POWER ON RESET CIRCUIT 65


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REFRENCES

[1] The 8051 Microcontroller and Embedded System, Muhammad Ali Mazidi and

Jancie Gillespie Mazidi,

[2] Myke Predko, Programming and Customising the 8051 Microcontroller,TMH

[3] The 8051 Microcontroller by Kenneth J. Ayala,

[4] http://www.keil.com/appnotes

[5] http://www.datasheetdirect.com

[6] (http://www.design-

reuse.com/articles/21745/8051_memeory_architecturer.html)

[7] (http://roboticsdream.blogspot.com/search/label/8051_microcontroller)

[8] https://reader009.{domain}/reader009/html5/0428/5ae38c9aa3055/5ae38cc5b4f24.jpg)

[9] ( http://www.free-circuits.com/circuits//-segment-rolling-display)
http://www.keil.com/appnoteshttp://www.keil.com/appnoteshttp://www.datasheetdirect.com/http://www.design-reuse.com/articles/21745/8051_memeory_architecturer.htmlhttp://www.design-reuse.com/articles/21745/8051_memeory_architecturer.htmlhttp://www.design-reuse.com/articles/21745/8051_memeory_architecturer.htmlhttp://www.design-reuse.com/articles/21745/8051_memeory_architecturer.htmlhttp://roboticsdream.blogspot.com/search/label/8051_microcontrollerhttp://roboticsdream.blogspot.com/search/label/8051_microcontrollerhttp://www.design-reuse.com/articles/21745/8051_memeory_architecturer.htmlhttp://www.design-reuse.com/articles/21745/8051_memeory_architecturer.htmlhttp://www.datasheetdirect.com/http://www.keil.com/a

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