CHAPTER 1

1. INTRODUCTION

In this age of digital technology, every device and its operation has become

digital based. Now with digital based door lock systems, it is easier to control the

door movement of the car or house. The new automated door lock system does not

need a key to lock or unlock the door of the car or house. This digital door entry

system is in fact controlled by cell-phone which is actually performing the role of

remote over here. The keyless door remote is an electronic circuit based device.

This remote transmits DTMF signals via air to another device of the system

installed in the car door or house door.. The keyless car remote can be operated

from any corner of the world. The working of this locking system is very simple.

You just have to carry the cell phone with yourself and you can control the locks

from anywhere without any problem. It works on the entry number. The owner has

to press that entry number on the cell phone for controlling the locking system. The

entry number is unique in nature and so is the remote device of an automatic

keyless system. You can install a keyless entry system in your house as well as in

your vehicle. Now, a days theft cases are increasing everywhere and the key based

locking system is no longer a safe option. It is quite easy for thieves and robbers to

open the traditional key based doors either with duplicate keys or some other way.

Therefore for safety of your house and vehicle, this system can be installed. With

this system, you will never be in tension of leaving your house and vehicle out of

your supervision. Not only this ,it also help us to move out of some really odd

situations like you locked the door and left and in your absence other members

came back and then they have to wait outside if they were not having key with

themselves.

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1.1 Motivation

Keyless entry has been a luxury whose availability is confined primarily to

vehicles. The cell phone security system takes this idea of keyless entry and

transforms it into a convenient, versatile security system that utilizes cell phone

technology and the landline telephone network. By taking advantage of caller

identification and dual-tone multi-frequency signaling, the security system has the

ability to introduce two-levels of security. The first level will be decoding the

calling party’s identification information while the second level would consist of

the user attempting a password entry over the phone.. By combining the mobility

of this telecommunication medium with microcontrollers, the system achieves a

secure, convenient, and automated form of security for a place of residence.

1.2 PROBLEM DEFINITION

The cell phone security system is the result of a fusion of a creative idea with an

attempt to motivate change. Even though modern technology has allowed for the

automation of many aspects of domestic lifestyles, from automatic motion sensing

lights to automatic garage door openers, home security has not seen much benefit

from this revolution. Household entry has long been a very manual routine with

little effort to automate the process. Entry into a residence is still primarily limited

to a manual process which involves inserting a key into a bolt and physically

moving the locking-mechanism

1.3 OBJECTIVE OF PROJECT

The fundamental requirements for the cell phone security system remained fixed

throughout the design process. The goal was to design a system which would allow

the user automated and convenient access to their home security system through a

telephone network.

The fundamental objectives of the system include:

1. Correctly decode the DTMF signals from the user.

2. Correctly decode caller identification information from the phone line.

3. Allow the user to automatically lock the entryway.

4. Allow the user to automatically unlock the entryway.

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1.4 LIMITATIONS OF PROJECT

The cell phone security system aims to change this. The system takes advantage of

the widespread acceptance of cell phones in today’s society in conjunction with the

deep-rooted standards of the landline telephone network to introduce automation

and convenience. The system will allow a user to use their cell phone to place a

call into their home security system. Once the system verifies the caller, the caller

is then allowed to attempt a password entry. Upon successfully entering a

password, the system will automatically unlock the door and grant entrance. This

automation introduces a form of secure, keyless entry into a residence along with

the convenience of a fully responsive security system monitor. The system will

primarily interface with telephony protocols which include dual tone multi

frequency (DTMF), caller identification (CID), and some applicable telephony

circuit standards.

1.5 ORGANIZATION OF DOCUMENTATION

In this project documentation we have initially put the definition and

objective of the project as well as the design of the project which is followed by

the implementation and testing phases. Finally the project has been concluded

successfully and also the future enhancements of the project were given in this

Documentation.

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CHAPTER 2

LITERATURE SURVEY

2.1 INTRODUCTION

Design for an automated door locks(smart key less entry), Biometric

attendance, lecture theater/hall monitor system, railway station display, Automated

Parking System, gps navigation system, Circuit Encoder ARC M3EA from Artech

for RF Remote Control, pic16f877 interfaced to max sonar ez1 sensor, Infrared

Head phone, Microcontroller application, The first method of DTMF generation

provides two PWM (Pulse Width Modulation) outputs on pins G3 and G2 of the G

port for 100 ms. These two PWM outputs represent the selected high band and low

band frequencies respectively, and must be combined externally with an LM324 op

amp or equivalent feedback circuit to produce the DTMF signal DTMF (Dual Tone

Multiple Frequency) is associated with digital telephony, and provides two selected

output frequencies (one high band, one low band) for a duration of 100 ms. DTMF

generation consists of selecting and combining two audio tone frequencies

associated with the rows (low band frequency) and columns (high band frequency)

of a push-button touch tone telephone keypad.

According to the current article, DTMF was first introduced to the public at

the NY World's Fair in 1964. It was, however, in full "field test" usage in multiple

small towns in the US by then. Most notably, it was first used in Findlay Ohio in

1960 and then in Greensburg, PA in 1961.

WHAT IS DUAL TONE MULTI-FREQUENCY

DTMF is the global standard for audible tones that represent the digits on a

phone keypad with touch-tone land-line phones, pressing a key on the dial pad

generates the corresponding DTMF tone for that key. The land-line phone system

can then "listen" and decode that tone to determine which key was pressed,

enabling dialing.

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Mobile phone networks use digital signals instead of DTMF for direct dialing,

but DTMF is still used over mobile phones to navigate automated systems such as

phone menus, and for secondary dialing, such as using a calling card. Each DTMF

"tone" is actually two tones - a low-frequency tone and a high-frequency tone -

combined. (Hence the name "dual tone multi-frequency".) Looking at the standard

phone keypad as a grid, the low tone corresponds to the row, while the high tone

corresponds to the column.

2.2 EXISTING SYSTEM

In the existing system of the project we had use the doors in lock systems

keys are obsolete they are use man power open and close the doors. It requires the

human energy.

2.3 DISADVANTAGES OF EXISTING SYSTEM

As mentioned above the earlier system has use the doors in lock systems

keys are obsolete there are no use of the electrical devices there are use the

mechanical systems. After being inspired by the mechanical door

opening system in that. I mean c'mon, door locks with keys are obsolete. Everyone

uses them. They’re so old fashioned! ...The second part of this project was to build

a DTMF decoder by use of mobile with the soft ware’s requirements.

2.4 PROPOSED SYSTEM

As the above disadvantages can’t be solved with in this application has

been Proposed and also the handling will be much improved than the existing

system as we are implementing the special method called door lock through

telephone using dtmf decoder.

Here the door lock through telephone using this is control the over all door

locking system there open are close the is process will take by D.C motors and

LED’S that can final operate.

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CHAPTER 3

ANALYSIS

3.1 INTRODUCTION

After analyzing the requirements of the task to be performed, the next step

is to analyze the problem and understand its context. The first activity in the phase

is studying the existing system and other is to understand the requirements and

domain of the new system. Both the methods are equally important but the first

system states as a basis of giving the functional specifications and then successful

design of the proposed system. Understanding the properties and requirements of a

new system is more difficult and requires creative thinking as well as

understanding of existing system is also difficult. Improper understanding of

present system can lead diversion from solution

3.2 Hardware requirement

3.2.1 DC Motors

Industrial applications use dc motors because the speed-torque relationship can be varied to almost any useful form -- for both dc motor and regeneration applications in either direction of rotation. Continuous operation of dc motors is commonly available over a speed range of 8:1. Infinite range (smooth control down to zero speed) for short durations or reduced load is also common.

Dc motors are often applied where they momentarily deliver three or more times their rated torque. In emergency situations, dc motors can supply over five times rated torque without stalling (power supply permitting).

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Fig. 3.2.1 DC motor

Dynamic braking (dc motor-generated energy is fed to a resistor grid) or regenerative braking (dc motor-generated energy is fed back into the dc motor supply) can be obtained with dc motors on applications requiring quick stops, thus eliminating the need for, or reducing the size of, a mechanical brake.

Dc motors feature a speed, which can be controlled smoothly down to zero, immediately followed by acceleration in the opposite direction -- without power circuit switching. And dc motors respond quickly to changes in control signals due to the dc motor's high ratio of torque to inertia.

DC Motor types: Wound-field dc motors are usually classified by shunt-wound, series-wound, and compound-wound. In addition to these, permanent-magnet and brushless dc motors are also available, normally as fractional-horsepower dc motors. Dc motors may be further classified for intermittent or continuous duty. Continuous-duty dc motors can run without an off period.

DC Motors - Speed control: There are two ways to adjust the speed of a wound-field dc motor. Combinations of the two are sometimes used to adjust the speed of a dc motor.

DC Motor - Shunt-field control: Reel drives require this kind of control. The

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dc motor's material is wound on a reel at constant linear speed and constant strip tension, regardless of diameter.

Control is obtained by weakening the shunt-field current of the dc motor to increase speed and to reduce output torque for a given armature current. Since the rating of a dc motor is determined by heating, the maximum permissible armature current is approximately constant over the speed range. This means that at rated current, the dc motor's output torque varies inversely with speed, and the dc motor has constant-horsepower capability over its speed range.

DC Motors - Selection: Choosing a dc motor and associated equipment for a given application requires consideration of several factors.

DC Motors - Speed range: If field control is to be used, and a large speed range is required, the base speed must be proportionately lower and the motor size must be larger. If speed range is much over 3:1, armature voltage control should be considered for at least part of the range. Very wide dynamic speed range can be obtained with armature voltage control. However, below about 60% of base speed, the motor should be de-rated or used for only short periods.

DC Motors - Speed variation with torque: Applications requiring constant speed at all torque demands should use a shunt-wound dc motor. If speed change with load must be minimized, a dc motor regulator, such as one employing feedback from a tachometer, must be used. When the dc motor speed must decrease as the load increases, compound or series-wound dc motors may be used. Or, a dc motor power supply with a drooping volt-ampere curve could be used with a shunt-wound dc motor.

DC Motors - Reversing: This operation affects power supply and control, and may affect the dc motor's brush adjustment, if the dc motor cannot be stopped for switching before reverse operation. In this case, compound and stabilizing dc motor windings should not be used, and a suitable armature-voltage control system should supply power to the dc motor.

DC Motors - Duty cycle: Direct current motors are seldom used on drives that run continuously at one speed and load. Motor size needed may be determined by either the peak torque requirement or heating.

DC Motors - Peak torque: The peak torque that a dc motor delivers is limited by that load at which damaging commutation begins. Dc motor brush and commentator damage depends on sparking severity and duration. Therefore, the dc motor's peak torque depends on the duration and frequency of occurrence of the overload. Dc motor peak torque is often limited by the maximum current that the power supply can deliver.

Dc motors can commutate greater loads at low speed without damage. NEMA standards specify that machines powered by dc motors must deliver at least 150% rated current for 1 min at any speed within rated range, but most dc motors do much better.

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DC Motors - Heating: Dc motor temperature is a function of ventilation and electrical/mechanical losses in the machine. Some dc motors feature losses, such as core, shunt-field, and brush-friction losses, which are independent of load, but vary with speed and excitation.

The best method to predict a given dc motor's operating temperature is to use thermal capability curves available from the dc motor manufacturer. If curves are not available, dc motor temperature can be estimated by the power-loss method. This method requires a total losses versus load curve or an efficiency curve.

For each portion of the duty cycle, power loss is obtained and multiplied by the duration of that portion of the cycle. The summation of these products divided by the total cycle time gives the dc motor's average power loss. The ratio of this value to the power loss at the motor rating is multiplied by the dc motor's rated temperature rise to give the approximate temperature rise of the dc motor when operated on that duty cycle.

Selecting DC motors

Sizing a DC motor to accurately meet a set of requirements can be a thankless task. Having to choose between brush-type or brushless motors can complicate the selection. Even experienced designers may sometimes overlook critical motor parameters and find problems after the system is up and running. In the worst case, starting over may be the only alternative.

Experts, however, use an expedient procedure to properly size and select dc motors. This procedure is based upon an accurate definition of the target system parameters and designer experience.

Dc motor parameters: Fortunately, several motor parameters are the same for both brush-type and brushless dc motors. One of these is motor constant; Km. It is important but widely overlooked. It is used during motor sizing because it is a figure of merit of the motor power-to-torque ratio. Km is proportional to the ratio of peak torque, Tp, to peak power, Pp, at stall: Km = Tp / Pp. Km is also proportional to the ratio of torque sensitivity, Kt, to motor terminal resistance, Rm:Km = Kt / Rm.

After the required Km has been determined, a candidate motor with this value or greater is selected from a catalog. The motor is only a candidate at this point because other factors must be determined. As the design selection progresses, some trade-offs typically take place. For example, the motor must also satisfy physical size and inertia requirements.

Winding resistance is a major factor in motor selection because it seriously affects Km. Winding resistance and motor current produce power loss in the form of heat and motor temperature rise (TPR). These losses are also referred to as I2R losses and directly degrade motor efficiency.

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Most motor windings are copper wire which has a positive temperature coefficient. A winding temperature rise from 25 to 155°C increases wire resistance as much as 50%. Likewise, a proportional decrease in resistance occurs for temperature drops.

A three-step procedure determines the value of resistance change from a specified initial power input. First, a quality factor, F, is computed from known wattage and temperature. Second, the hot-condition wattage, Wh is calculated. Third, the quality factor is used to find final temperature rise, Trf.

Quality factor is:

Where Wc = initial input power, cold, W; TPR = motor temperature rise, °C/W; and Tamb = ambient temperature, °C.

Hot wattage is Wh = (F)(Wc). The final temperature is Trf = (Wh)(TPR).

However, factor F is valid only over a restricted range of values for a part of the denominator, where n = Wc(TPR)/(234.5 + Tamb). If n >1, then F is negative or infinity, signifying thermal runaway that burns open the motor. But if n <1, then F is positive and the motor will stabilize at Trf or less.

Core losses:

Hysteresis and eddy currents in the core also make motor temperature rise. At high speeds, these losses can produce as much or more heat than I 2R losses. Core losses depend primarily on the motor design. Design factors affecting those losses include lamination thickness, flux densities in the armature, and frequencies generated in the core that depend upon the number of poles and speed. Catalog specifications may not include core loss data, so designers must measure it by testing several sample motors. The data may also be available directly from the motor manufacturer. Ambient temperature is the third most important factor determining motor temperature rise. A motor having a winding temperature rating of 155°C and operating in an ambient temperature of 100°C has only a 55°C allowable temperature rise. Core losses and I2R losses quickly cut the 55°C margin under load. An ideal room ambient temperature of 25°C, by comparison, allows a 130°C temperature rise. Use of heat sinks and air or fluid cooling moderates the temperature rise value considerably. The TPR rating of the motor per watt of input power, °C/W, is usually in the catalog or data sheet for unmounted motors. The TPR for the same motor, but mounted, TPR´ can be 25% of the unmounted value. A conservative designer could ignore the reduced TPR in his calculations. But he would specify a motor much larger and more expensive than necessary.

Magnet properties: Dc motors use a variety of permanent-magnet materials. Early designs employed ceramic or ferrite and AlNiCo magnets. These materials

10

are still widely applied, however, in automobiles and other areas where low cost as well as reliability is important. Newer designs use rare-earth samarium-cobalt and neodymium magnets. Most magnets have stable magnetic properties within the normal operating temperature range of the motor. But some magnets have a higher temperature coefficient than others. High temperature-coefficient magnets may become too weak if operated at high temperatures for extended periods. Depending on the magnetic material and slope of the motor's magnetic circuit, torque degradation may result over a wide temperature range. Ceramic or ferrite magnets lose about 0.13% / °C of their remanence above 25°C, while rare earth and AlNiCo may lose only 0.03% / °C. But this loss is generally reversible if the temperature is kept within the motor rating. Colder temperatures are seldom a problem. Since the coefficient curve is linear, magnets are stronger at lower temperatures.

Some grades of rare-earth magnets are more sensitive to temperature than others. Magnets in the neodymium family may have irreversible magnetic losses under wide temperature changes. These magnets have the highest maximum-energy product (MEP), a figure of merit, of any commercial magnet now available. High MEP comes at a premium and should not be lost to temperature extremes. Neodymium magnets are continually being improved with lower temperature coefficients to make them as stable as other rare-earth grades. Peak loads applied to AlNiCo and ceramic dc motors can degrade their magnetic properties. AlNiCo motors have a peak current rating which usually corresponds to a point above the knee of the B/H curve. Current exceeding this rating, caused by either a current spike or a constant dc input, are over the knee and cause permanent demagnetization. A demagnetized AlNiCo motor may only provide 50 to 60% of its original torque. Fortunately, rare-earth magnets are not as sensitive to demagnetization as AlNiCo and ceramic.

Motor sizing: Motor sizing takes into account all the above motor parameters and specifications. Also, the motor inertia and load must be defined for both transient and steady-state conditions. This inertia is critical since torque during acceleration exceeds torque at constant speed. Two examples explain the sizing of dc motors for typical applications. The first example considers the selection and sizing of a brush-type dc motor. The second concerns a sterile outer-space environment requiring a brushless dc motor.

3.2.2 LIGHT EMITTING DIODE (LED)

LED's are special diodes that emit light when connected in a circuit. They

are frequently used as "pilot" lights in electronic appliances to indicate whether the

circuit is closed or not. As a clear (or often colored) epoxy case enclosed the heart

of an LED, the semi-conductor chip.

Fig. 3.2.2.1: SYMBOL OF LED

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Fig. 3.2.2.2: CROSS SECTIONAL VIEW OF LED

Working

The most important part of a light emitting diode (LED) is the semi-

conductor chip located in the center of the bulb as shown. The chip has two regions

separated by a junction. The p region is dominated by positive electric charges, and

the n region is dominated by negative electric charges. The junction acts as a

barrier to the flow of electrons between the p and the n regions. Only when

sufficient voltage is applied to the semi-conductor chip, can the current flow and

the electrons cross the junction into the p region.

Fig. 3.2.2.3 Semi conductor Chip

In the absence of a large enough electric potential difference (voltage) across the

LED leads, the junction presents an electric potential barrier to the flow of

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electrons. When sufficient voltage is applied to the chip across the leads of the

LED, electrons can move easily in only one direction across the junction between

the p and n regions. In the p region there are many more positive than negative

charges. In the n region the electrons are more numerous than the positive electric

charges. When a voltage is applied and the current starts to flow, electrons in the n

region have sufficient energy to move across the junction into the p region. Once in

the p region the electrons are immediately attracted to the positive charges due to

the mutual Coulomb forces of attraction between opposite electric charges. When

an electron moves sufficiently close to a positive charge in the P region, the two

charges "re-combine”. Each time an electron recombines with a positive charge;

electric potential energy is converted into electromagnetic energy. For each

recombination of a negative and a positive charge, a quantum of electromagnetic

energy is emitted in the form of a photon of light with a frequency characteristic of

the semi-conductor material (usually a combination of the chemical elements

gallium, arsenic and phosphorus). Only photons in a very narrow frequency range

can be emitted by any material.

Color of L.E.D

LED's that emit different colors are made of different semi-conductor

materials, and require different energies to light them.

Fig 3.2.2.4 color of L.E.D

The color of an LED is determined by the semiconductor material, not by the

coloring of the 'package' (the plastic body). LEDs of all colors are available in

uncolored packages which may be diffused (milky) or clear (often described as

13

'water clear'). The colored packages are also available as diffused (the standard

type) or transparent.

3.2.3 POWER SUPPLY UNIT

BLOCK DIAGRAM

Fig 3.2.3.1 Block diagram

As we all know any invention of latest technology cannot be activated without the source of power. So it this fast moving world we deliberately need a proper power source which will be apt for a particular requirement. All the electronic components starting from diode to Intel IC’s only work with a DC supply ranging from _+5v to _+12. we are utilizing for the same, the most cheapest and commonly available energy source of 230v-50Hz and stepping down , rectifying, filtering and regulating the voltage. This will be dealt briefly in the forth-coming sections.

STEP DOWN TRANSFORMER

When AC is applied to the primary winding of the power transformer it can either be stepped down or up depending on the value of DC needed. In our circuit the transformer of 230v/15-0-15v is used to perform the step down operation where a 230V AC appears as 15V AC across the secondary winding . One alteration of input causes the top of the transformer to be positive and the bottom negative. The next alteration will temporarily cause the reverse. The current rating of the transformer used in our project is 2A. Apart from stepping down AC voltages , it gives isolation between the power source and power supply circuitries.

BRIDGE RECTIFIER

In the power supply unit, rectification is normally achieved using a solid state diode. Diode has the property that will let the electron flow easily in one direction at proper biasing condition . As AC is applied to the diode, electrons only flow when the anode and cathode is negative. Reversing the polarity of voltage will not permit electron flow.

For a positive cycle, two diodes are connected to the positive voltage at the top winding and only one diode conducts . At the same time one of the other two

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Step Down Transformer

Bridge Rectifier

PositiveCharge Capacitor

Positive Voltage Regulator IC 7805

LPF

diodes conducts for the negative voltage that is applied from the bottom winding due to the forward bias for that diode. In this circuit due to positive half cycleD1 & D2 will conduct to give 10.8v pulsating DC. The DC output has a ripple frequency of 100Hz. Since each altercation produces a resulting output pulse, frequency = 2*50 Hz. The output obtained is not a pure DC and therefore filtration has to be done.

VOLTAGE REGULATORS

The voltage regulators play an important role in any power supply unit. The primary purpose of a regulator is to aid the rectifier and filter circuit in providing a constant DC voltage to the device. Power supplies without regulators have an inherent problem of changing DC voltage values due to variations in the load or due to fluctuations in the AC liner voltage. With a regulator connected to the DC output, the voltage can be maintained within a close tolerant region of the desired output. IC7812 and 7912 is used in this project for providing +12v and –12v DC supply.

3.2.4 MICROCONTROLLER

The AT89C52 is a low-power, high-performance CMOS 8-bit

microcomputer with 8k bytes of Flash programmable and erasable read only

memory (PEROM)The device is manufactured using Atmel’s high-density

nonvolatile 11Memory technology and is compatible with the industry-standard

80C51 and 80C52 instruction set and Pin out. The on-chip Flash allows the

program memory to be reprogrammed in-system or by a conventional nonvolatile

memory programmer .By combining a versatile 8-bit CPU with Flash on a

monolithic chip.

Features

The AT89C52 provides the following standard features

8K Bytes of In-System Reprogrammable Flash Memory

128 bytes of Internal RAM (128 x 8-bit)

32 Programmable I/O Lines

Two 16-bit Timer/Counters

Five vector two-level interrupt architecture

A full duplex serial port

Three-level Program Memory Lock

Six Interrupt Sources

On-chip oscillator and clock circuit

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PIN DIAGRAM

.

Fig. 3.2.4.1 89c52 Microcontroller

Pin Description

VCC: Supply voltage.

GND: Ground.

Port 0 Port 0 is an 8-bit open-drain bi-directional I/O port. As an output port,

each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can

be used as high impedance inputs. Port 0 may also be configured to be the

multiplexed low order address/data bus during accesses to external program and

data memory. In this mode P0 has internal pull-ups. Port 0 also receives the code

bytes during Flash programming, and outputs the code bytes during program

verification. External pull-ups are required during program verification.

Port 1 Port 1 is an 8-bit bi-directional I/O port with internal pull-ups.

16

The Port 1 output buffers can sink/source four TTL inputs. When 1s are written to

Port 1 pins they are pulled high by the internal pull-ups and can be used as inputs.

As inputs, Port 1 pins that are externally being pulled low will source current (IIL)

because of the internal pull-ups. Port 1 also receives the low-order address bytes

during Flash programming and verification.

Port 2 Port 2 is an 8-bit bi-directional I/O port with internal pull-ups.

The Port 2 output buffers can sink/source four TTL inputs. When 1s are written to

Port 2 pins they are pulled high by the internal pull-ups and can be used as

inputs .As inputs, Port 2 pins that are externally being pulled low will source

current (IIL) because of the internal pull-ups. Port 2 emits the high-order address

byte during fetches from external program memory and during accesses to

externaldata16-bitaddresses

(MOVX@DPTR).Inthisapplication,itusesstrongmemoryuses internal

pullupswhenemitting1s.Duringaccessestoexternaldatamemorythatuses8-bit

addresses (MOVX @ RI); Port 2 emits the contents of the P2 Special Function

Register.

Port 3 Port 3 is an 8-bit bi-directional I/O port with internal pull-ups. The Port

3 output buffers can sink/source four TTL inputs. When 1s are written to Port 3

pins they are pulled high by the internal pull-ups and can be used as inputs. As

inputs, Port 3 pins that are externally being pulled low will source current (IIL)

because of the pull-ups .Port 3 also serves the functions of various special features

of the AT89C51 as listed below:

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Port Pin Alternate Functions

P3.0 RXD (serial input port)

P3.1 TXD (serial output port)

P3.2 INT0 (external interrupt 0)

P3.3 INT1 (external interrupt 1)

P3.4 T0 (timer 0 external input)

P3.5 T1 (timer 1 external input)

P3.6WR (external data memory Write

strobe)

P3.7RD (external data memory read

strobe)

Fig 3.2.4.2 Table of 89c52

Port 3 also receives some control signals for Flash programming and verification.

RST Reset input. A high on this pin for two machine cycles while the oscillator is running resets the device.

ALE/PROG

Address Latch Enable output pulse for latching the low byte of the address during

accesses to external memory. This pin is also the program pulse input (PROG)

during Flash programming. In normal operation ALE is emitted at a constant rate

of 1/6 the oscillator frequency, and may be used for external timing or clocking

purposes. Note, however, that one ALE pulse is skipped during each access to

external Data Memory. If desired, ALE operation can be disabled by setting bit 0

of SFR location 8EH. With the bit set, ALE is active only during a MOVX or

MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-

disable bit has no effect if the microcontroller is in external execution mode.

Program Store Enable is the read strobe to external program memory. When the

AT89C51 is executing code from external program memory, is activated

twice each machine cycle, except that two activations are skipped during

each access to external data memory.

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/VPP

External Access Enable must be strapped to GND in order to enable the device to

fetch code from external program memory locations starting at 0000H up to

FFFFH. Note, however, that if lock bit 1 is programmed, will be internally

latched on reset. should be strapped to VCC for internal program executions.

Oscillator Characteristics

XTAL1 and XTAL2 are the input and output, respectively, of an inverting

amplifier which can be configured for use as an on-chip oscillator, as shown in

Figure 1. Either a quartz crystal or ceramic resonator may be used.

To drive the device from an external clock source, XTAL2 should be left

unconnected while XTAL1 is driven as shown in Figure 2. There are no

requirements on the duty cycle of the external clock signal, since the input to the

internal clocking circuitry is through a divide-by-two flip-flop, but minimum and

maximum voltage high and low time specifications must be observed.

OSCILLATOR CONNECTIONS

Fig 3.2.4.3 oscillator connections

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At89c51: Types of Memory

The 89c51 has three very general types of memory The memory types are On-Chip

Memory, External Code Memory, and External RAM

Fig 3.2.4.4 Types of memory

On-Chip Memory

refers to any memory (Code, RAM, or other) that physically exists on the

microcontroller itself. On-chip memory can be of several types, but we'll get into

that shortly.

External Code Memory

is code (or program) memory that resides off-chip. This is often in the

form of an external EPROM.

External RAM

is RAM memory that resides off-chip. This is often in the form of

standard static RAM or flash RAM.

Code Memory:

Code memory is the memory that holds the actual 89c51 program that is to be

run. This memory is limited to 64K and comes in many shapes and sizes: Code

20

memory may be found on-chip, either burned into the microcontroller as ROM or

EPROM. Code may also be stored completely off-chip in an external ROM or,

more commonly, an external EPROM. Flash RAM is also another popular method

of storing a program. Various combinations of these memory types may also be

used--that is to say, it is possible to have 4K of code memory on-chip and 64k of

code memory off-chip in an EPROM .When the program is stored on-chip the

64K maximum is often reduced to 4k, 8k, or 16k. This varies depending on the

version of the chip that is being used.

External RAM:

As an obvious opposite of Internal RAM, the 89c51 also supports what is

called External RAM. As the name suggests, External RAM is any random access

memory which is found off-chip. Since the memory is off-chip it is not as flexible

in terms of accessing, and is also slower. For example, to increment an Internal

RAM location by 1 requires only 1 instruction and 1 instruction cycle. To

increment a 1-byte value stored in External RAM requires 4 instructions and 7

instruction cycles. In this case, external memory is 7 times slower .What External

RAM loses in speed and flexibility it gains in quantity. While Internal RAM is

limited to 128 bytes (256 bytes with an 8052), the 89c51 supports External RAM

up to 64K.

On-Chip Memory

As mentioned, the 89c51 includes a certain amount of on-chip memory.

On-chip memory is really one of two types: Internal RAM and Special Function

Register (SFR) memory. The layout of the 89c51's internal

memory is presented in the following memory map..

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Fig 3.2.4.5 on chip memory

As is illustrated in above map, the 89c51 has a bank of 128 bytes of Internal RAM.

This Internal RAM is found on-chip on the 89c51 so it is the fastest RAM

available, and it is also the most flexible in terms of reading, writing, and

modifying it’s contents. Internal RAM is volatile, so when the 89c51 is reset this

memory is cleared.

Register Banks

The 89c51 uses 8 "R" registers which are used in many of its instructions.

These "R" registers are numbered from 0 through 7 (R0, R1, R2, R3, R4, R5, R6,

and R7). These registers are generally used to assist in manipulating values and

moving data from one memory location to another the Accumulator. Thus if the

Accumulator (A) contained the value 6 and R4 contained the value 3, the

Accumulator would contain the value 9 after this instruction was executed.

However, as the memory map shows, the "R" Register R4 is really part of Internal

RAM. Specifically, R4 is address 04h. This can be see in the bright green section

of the memory map. But, the 89c51 has four distinct register banks. When the

89c51 is first booted up, register bank 0 (addresses 00h through 07h) is used by

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default. However, your program may instruct the 89c51 to use one of the alternate

register banks; i.e., register banks 1, 2, or 3. In this case, R4 will no longer be the

same as Internal RAM address 04h. For example, if your program instructs the

89c51 to use register bank 3, "R" register R4 will now be synonymous with

Internal RAM address 1Ch.

The concept of register banks adds a great level of flexibility to the 89c51,

especially when dealing with interrupts (we'll talk about interrupts later). However,

always remember that the register banks really reside in the first 32 bytes of

Internal RAM.

BIT MEMORY

The 89c51, being a communications-oriented microcontroller, gives the

user the ability to access a number of bit variables. These variables may be either 1

or 0. There are 128 bit variables available to the user, numbed 00h through 7Fh.

The user may make use of these variables with commands such as SETB and CLR.

For example, to set bit number 24 (hex) to 1 you would execute the instruction:

SETB 24h

It is important to note that Bit Memory is really a part of Internal RAM. In fact, the

128 bit variables occupy the 16 bytes of Internal RAM from 20h through 2Fh.

Thus, if you write the value FFh to Internal RAM address 20h you’ve effectively

set bits 00h through 07h. Bit variables 00h through 7Fh are for user-defined

functions in their programs. However, bit variables 80h and above are actually

used to access certain SFRs on a bit-by-bit basis.

89c51: Basic Registers

The Accumulator

The Accumulator, as it’s name suggests, is used as a general register

to accumulate the results of a large number of instructions. It can hold an 8-bit (1-

byte) value and is the most versatile register the 89c51 has due to the shear number

of instructions that make use of the accumulator. More than half of the 89c51’s 255

instructions manipulate or use the accumulator in some way.

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The "R" registers:

The "R" registers are a set of eight registers that are named R0, R1, etc.

up to and including R7.These registers are used as auxillary registers in many

operations. To continue with the above example, perhaps you are adding 10 and

20. The original number 10 may be stored in the Accumulator whereas the value

20 may be stored in, say, register R4. To process the addition you would execute

the command

The "B" Register:

The "B" register is very similar to the Accumulator in the sense that it

may hold an 8-bit (1-byte) value. The "B" register is only used by two 89c51

instructions: MUL AB and DIV AB. Thus, if you want to quickly and easily

multiply or divide A by another number, you may store the other number in "B"

and make use of these two instructions .Aside from the MUL and DIV instructions,

the "B" register is often used as yet another temporary storage register much like a

ninth "R" register.

The Data Pointer (DPTR):

The Data Pointer (DPTR) is the 89c51’s only user-accessible 16-bit (2-

byte) register. The Accumulator, "R" registers, and "B" register are all 1-byte

values. DPTR, as the name suggests, is used to point to data. It is used by a number

of commands which allow the 89c51 to access external memory. When the 89c51

accesses external memory it will access external memory at the address indicated

by DPTR. While DPTR is most often used to point to data in external memory,

many programmers often take advantage of the fact that it’s the only true 16-

register available. It is often used to store 2-byte values which have nothing to do

with memory locations.

The Program Counter (PC)

The Program Counter (PC) is a 2-byte address which tells the 89c51

where the next instruction to execute is found in memory. When the 89c51 is

initialized PC always starts at 0000h and is incremented each time an instruction is

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executed. It is important to note that PC isn’t always incremented by one. Since

some instructions require 2 or 3 bytes the PC will be incremented by 2 or 3 in these

cases

The Stack Pointer (SP)

The Stack Pointer, like all registers except DPTR and PC, may hold

an 8-bit (1-byte) value. The Stack Pointer is used to indicate where the next value

to be removed from the stack should be taken from.

3.3 Software Requirement Specification

One core strength of the Sensor Integration Group is the common software

product, Multi-Input Data Acquisition System (MIDAS), which can

simultaneously communicate with each interface. The software leverages the

symmetric multi-processor capabilities and is highly multithreaded -- thus capable

of handling several I/O and processing tasks simultaneously. Multiple tasks can

run independent of one another or coordinate for increased acquisition capacity or

parallel operations. The software can be synchronized across multiple servers for

additional capacity or remote acquisition capabilities. MIDAS is supported under

both the Windows and Linux platforms.

The PC Test Set 2000 is an engineering software tool for the Windows platform

designed to acquire and process multi-channel data and provide display and

analysis tools. Designed for use in conjunction with acoustic sonar systems, the PC

Test Set acquires raw data from a telemetry source and transforms it into the time,

spectral, or spatial domains. The data is calibrated and displayed for the user who

can use the built-in tools to analyze the data. In addition, the PC Test Set has

automated tools to inform technicians of the health of the sonar system.

3.3.1 User Requirements

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This Multi channel system build with the use of embedded system it often

runs with limited computer hardware resources such as small or no keyboard,

screen, and little memory. Simple embedded devices use buttons, LEDs, and small

character- or digit only displays, often with a simple menu system.

The rise of the World Wide Web has given embedded designers another

quite Different option: providing a web page interface over a network connection.

This

Avoids the cost of a sophisticated display, yet provides complex input and display

Capabilities when needed, on another computer. This is successful for remote,

Permanently installed equipment. In particular, routers take advantage of this

ability.

Embedded Systems talk with the outside world via peripherals, such as:

Serial Communication Interfaces (SCI): RS-232, RS-422, RS-485 etc.

Synchronous Serial Communication Interface: I2C, JTAG, SPI, SSC and ESSI

Universal Serial Bus (USB)

Networks: Controller Area Network, Lon Works, etc

Timers: PLL(s), Capture/Compare and Time Processing Unit.

3.3 Software requirements

Overview of KEIL CROSS C COMPILER

It is possible to create the source files in a text editor such as Notepad, run

the Compiler on each C source file, specifying a list of controls, run the Assembler

on each Assembler source file, specifying another list of controls, run either the

Library Manager or Linker (again specifying a list of controls) and finally running

the Object-HEX Converter to convert the Linker output file to an Intel Hex File.

Once that has been completed the Hex File can be downloaded to the target

hardware and debugged. Alternatively KEIL can be used to create source files;

automatically compile, link and covert using options set with an easy to use user

interface and finally simulate or perform debugging on the hardware with access to

C variables and memory. Unless you have to use the tolls on the command line, the

choice is clear. KEIL Greatly simplifies the process of creating and testing an

embedded application.

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1. Click on the Keil uVision Icon on Desktop

2. The following fig will appear.

3. Click on the Project menu from the title bar

4. Then Click on New Project

5. Save the Project by typing suitable project name with no extension in u r own

folder sited in either C:\ or D:\

6. Then Click on save button above.

7. Select the component for u r project. i.e. Atmel….

8. Click on the + Symbol beside of Atmel

9. Select AT89C51

10. Then Click on “OK”

11. The Following fig will appear

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12. Then Click either YES or NO………mostly “NO”

13. Now your project is ready to USE

14. Now double click on the Target1, you would get another option “Source group

1”

15. Click on the file option from menu bar and select “new”

16. The next screen will be as shown in next page, and just maximize it by double

Clicking on its blue boarder.

17. Now start writing program in either in “C” or “ASM”

18. For a program written in Assembly, then save it with extension “. asm” and

for “C” based program save it with extension “ .C”

19. Now right click on Source group 1 and click on “Add files to Group Source”

20. Now you will get another window, on which by default “C” files will appear.

21. Now select as per your file extension given while saving the file

22. Click only one time on option “ADD”

23. Now Press function key F7 to compile. Any error will appear if so happen.

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24. If the file contains no error, then press Control+F5 simultaneously.

25. The new window is as follows

26. Then Click “OK”

27. Now Click on the Peripherals from menu bar, and check your required port.

28. Drag the port a side and click in the program file.

29. Now keep Pressing function key “F11” slowly and observe.

30. You are running your program successfully.

A project contains enough information to take a set of source files and

generate exactly the binary code required for the application. Because of the high

degree of flexibility required from the tools, there are many options that can be set

to configure the tools to operate in a specific manner. It would be tedious to have

to set these options up every time the application is being built; therefore they are

stored in a project file. Loading the project file into KEIL informs KEIL which

source files are

required, where they are, and how to configure the tools in the correct way. KEIL

can

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then execute each tool with the correct options. It is also possible to create new

projects in KEIL. Source files are added to the project and the tool options are set

as

required. The project can then be saved to preserve the settings. The project also

stores such things as which windows were left open in the simulator/debugger, so

when a project is reloaded and the simulator or debugger started, all the desired

windows are opened. KEIL project files have the extension.

Simulator/Debugger:

The simulator/ debugger in KEIL can perform a very detailed simulation of a

micro controller along with external signals. It is possible to view the precise

execution time of a single assembly instruction, or a single line of C code, all the

way up to the entire application, simply by entering the crystal frequency. A

window can be opened for each peripheral on the device, showing the state of the

peripheral. This enables quick trouble shooting of mis-configured peripherals.

Breakpoints may be set on either assembly instructions or lines of C code, and

execution may be stepped through one instruction or C line at a time. The contents

of all the memory areas may be viewed along with ability to find specific variables.

In addition the registers may be viewed allowing a detailed view of what the

microcontroller is doing at any point in time.

The Keil Software 8051 development tools listed below are the programs

you use to compile your C code, assemble your assembler source files, link your

program together, create HEX files, and debug your target program.µVision2 for

Windows™ Integrated Development Environment: combines Project Management,

Source Code Editing, and Program Debugging in one powerful environment.

C51 ANSI Optimizing C Cross Compiler: creates relocatable object modules from

your C source code,

A51 Macro Assembler: creates relocatable object modules from your

8051 assembler source code,

BL51 Linker/Locator: combines relocatable object modules created by the

compiler and assembler into the final absolute object module,

LIB51 Library Manager: combines object modules into a library, which may be

used by the linker,

OH51 Object-HEX Converter: creates Intel HEX files from absolute object

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modules.

CHAPTER 4

4. DESIGN

4.1 INTRODUCTION

this project, we propose door lock through telephone using dtmf decoder

system that is Supposed to replace existing hardware and door key systems. The

Proposed system is advanced.

4.2 BLOCK DIAGRAM

Fig. 4.2: BLOCK DIAGRAM

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8051 Micro controller

Mobile

Crystal circuit

Crystal oscillator

ULN Driver

Stepper motor

Power Supply

4.3 BLOCK DIAGRAM EXPLANATION

In the figure shows the block diagram of the door lock through telephone

using DTMF decoder .In this diagram it consist of 8051 micro controller ,mobile,

crystal circuit, ULN driver, and stepper motor.

When we call to the mobile which is connected to the microcontroller it’s

automatically receives the call from another mobile. At the time of call going on if

we press the button 2 on other mobile which we called, it transfer the command to

the microcontroller as door close then the uln drive increases the power from 5v to

50v that time motor will rotate and the motor automatically closes the door. It is

useful if we are forgetting to lock the door in hurry we may close it by using

mobile.

At the same time if we press 3 on other mobile the motor will rotate one more

time then the door will automatically open.

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4.4 SCHEMATIC DIAGRAM

Fig 4.4 Schematic diagramThe above fig shows the schematic diagram of door lock through mobile phone using DTMF decoder.

In port1 P1.5, P1.7 is connected for mobile. And in port2 P2.0 to P2.6 is connected for ULN driver. From ULN driver one DC Motor is connected. This DC motor is in contact with the door for automatically closing that door. The power for motor to work will come from the ULN driver which is connected to the microcontroller in the ports of P2.0 to P2.6 and 40th pin Vcc.

The power supply which is regulated as 5v DC from 230v AC is connected to the microcontroller in 20th pin as ground and 40th pin as Vcc.

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CHAPTER 5

IMPLEMENTATION AND RESULTS

5.1 INTRODUCTION

The implementation part is the most important phase of the project. In this

phase, we code the entire project in the chosen software according to the design

laid during the previous phase. The code has to be in such a way that the door lock

through telephone using dtmf decoder requirements are satisfied and also not

complicated for the transition i.e., the door lock through telephone using dtmf

decoder compiling and processing at the controller is made by this code. The code

should be efficient for dump to the controller. In this manner, we can dump this

code to the controller by using Flash jet.

5.2 IMPLEMENTAION

The door lock through telephone using dtmf decoder is implemented by

using microcontroller of 8051. The Embedded C code for this door lock through

telephone using dtmf decoder will dump to this microcontroller by using keil

software.

Fig 5.2 Dumping of program

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5.3 RESULTS

The testing of implemented circuit about the by use of the door lock

through telephone using dtmf decoder is implemented the was D.C motor will rest

state the hade set will connect to GSM as shown in below figures.

Fig. 5.3.1: Door Lock through Telephone Using DTMF Decoder

The above diagram shows the cell phone is GSM the is given to power supply and 250v and to 9v D.C power supply and also to connect to D.C motor to operation was will be done .

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Fig 5.3.2 Out Put of Door Lock through Telephone Using Dtmf Decoder

The output of the GSM is operate then call that mobile to an other mobile so that call activated and press the 1 button and D.C motor will rotate start then press 2 button the D.C motor will be stopped.

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CHAPTER 6

CONCLUSION

We can also extend this project The implementation of door lock through

telephone using dtmf decoder is implemented is done successfully. The

communication is properly done without any interference between different

modules in the design. Design is done to meet all the specifications and

requirements. Software tools like Keil Uvision Simulator, Proload to dump the

source code into the microcontroller, Orcad Lite for the schematic diagram have

been used to develop the software code before realizing the hardware. Circuit is

implemented in Orcad and implemented on the microcontroller board. The

performance has been verified both in software simulator and hardware design.

The total circuit is completely verified functionally and is following the application

software. It can be concluded that the design implemented in the present work

provide portability, flexibility and the data transmission is also done with low

power consumption to counting purpose by making some changes in the Hardware

module

By using this circuit and proper power supply we can implement various

applications Such as fans, door locking systems, etc. By modifying this circuit and

using two relays we can achieve a task of opening and closing the door. We can

also extend this project to counting purpose by making some changes in the

Hardware module

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REFERENCES

1. Muhammad Ali Mazidi, Janice Gillispie Mazidi, Rolin D.McKinla

The 8051 Microcontroller and Embedded Systems Using Assembly and C,

Pearson Education Inc.., 2006, Second Edition.

2. Kenneth J.Ayala; The 8051 Microcontroller Architecture, Programming, and

Application; West Publishing Company, USA ,1991

3. B.Ram ; Computer Fundamentals Architecture and Organization ; New Age

International (P) Ltd., Publishers @2000, Third Edition

4. Horn, Delton T. ; Electronic Components A Complete Reference For Project

Builders ; McGraw-Hill/Tab Electronics @1991

5. E Balagurusamy ; Programming In ANSI C ; Tata McGraw-Hill Publishing

Company Ltd@2008,Fourth Edition

REFERENCES ON THE WEB

http://www.google.com

http://books.google.com

http://www.atmel.com

http://www.8051projects.net

http://www.ijens.org

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