A Project Report

On

METAL SHAPE DETECTOR

Submitted in partial fulfillment of requirement for the award of degree of

Bachelor of Technology

(Electronics and Communication Engineering)

2007-2011

Under the guidance of: Submitted by:

Mr. Parikshit Vashisht Lokanshu Arora(073052)

Gaurav kalra(073030)

Department of Electronics Engineering

Apeejay College of Engineering

Maharishi Dayanand University, Rohtak (Haryana)

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ACKNOWLEDGEMENT

It is our proud privilege to acknowledge with deep sense of gratitude & devotion for the keen interest & invaluable to us by revered faculty:

Dr. Sarabjit Singh (Principal of Apeejay College of Engineering, Sohna (Gurgaon))

Mr. Satinder Sharma (H.O.D. Of Dept. of Electronics Engineering in Apeejay college of Engineering, Sohna (Gurgaon)).

(Project Guide & lecturer of Dept. Of Electronics Engineering in Apeejay Styanand Mr. Parikshit Vashisht University (Gurgaon)).

Who responded to our queries by providing necessary data and information, thus helping us to complete the project successfully. It is because of their guidance, constant encouragement and inspiration that we have able to accomplish this task.

It is our pleasant duty to thank all staff members of Department of Electronics &who never hesitated in extending the cooperation from time to time during this project.

Thanking you once again,

Gaurav Kalra(073030)

Lokanshu Arora(073052)

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DECLARATION

We GAURAV KALRA and LOKANSHU ARORA hereby declare that the work presented in the project report titled METAL SHAPE DETECTOR to the Department of Electronics Engineering, Apeejay college of engineering , Sohna (Gurgaon) for the partial fulfillment of the requirement for the award of degree of the “Bachelor of Technology in Electrical Engineering” is authentic record of our work carried out during final year, 2010-2011 at our college premises under the supervision of Mr. Parikshit Vashisht (Project Guide & lecturer of Dept. Of Electronics Engineering in Apeejay Styanand University (Gurgaon)).

The matter embodied in this project report has not been submitted elsewhere by anybody for the award of any degree or diploma.

GAURAV KALRA LOKANSHU ARORA

(O73030) (073052)

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APEEJAY COLLEGE OF ENGINEERING

Vill–Silani (Sohna – Palwal Road)

Sohna (Gurgaon), Haryana

CERTIFICATE

This is to certify that the Project entitled “METAL SHAPE DETECTOR” which is being submitted by GAURAV KALRA(073030) and LOKANSHU ARORA(073052), to the department of Electronics Engineering, Apeejay College of Engineering, Sohna (Gurgaon) for the award of degree in Electronics Engineering, is a record of bonafide project work, they have carried out under my supervision & guidance.

The result contained in this project has not been submitted to any other university or institute for the award of a degree or diploma.

Mr. Parikshit Vashisht (Project Guide)

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TABLE OF CONTENTS

1. Introduction.

2. Block diagram

3. Block Diagram Description

4. Main Part or Features of the project.

5. Circuit diagrams or Layout.

6. Different tools used.

7. The original programming code for the project

8. Future scope and applications

9. Reference and data sheets.

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INTRODUCTION

A sensor is a device that measures a physical quantity and converts it into a signal which can be read by an observer or by an instrument. Sensors are used in everyday objects such as touch-sensitive elevator buttons and lamps which dim or brighten by touching the base. There are also innumerable applications for sensors of which most people are never aware. Applications include cars, machines, aerospace, medicine, manufacturing and robotics.

FINGER PRINT SENSOR

A fingerprint sensor is an electronic device used to capture a digital image of the fingerprint pattern. The captured image is called a live scan. This live scan is digitally processed to create a biometric template (a collection of extracted features) which is stored and used for matching. This is an overview of some of the more commonly used fingerprint sensor technologies.

METALLIC SHAPE DETECTOR

A metallic shape detector is an electronic device used to detect the shape of a metallic device . This metallic device can be of any shape like human face ,

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recognition patterns , etc. The detectable metal object is to be inserted into the device and then the device can detect the shape of that metallic object and we get the signal.

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BLOCK DIAGRAM

BLOCK DIAGRAM DESCRIPTION

In the given block diagram,we have Detecting object,Encoder,8051 Microcontroller,5 V Power Supply and led detection.The detecting object is entered into the encoder . The encoder will convert the larger number of inputs into binary inputs. The binary inputs are then processed by microcontroller using a program code in assembly language .All these components work on 5 V power supply . Then the shape of the detecting object is detected by led detection. AT89C51 is a 40 pin microcontroller which belongs to 8051 series of microcontroller

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FEATURES OF THE PROJECT:

5 VOLTS POWER SUPPLY

220 VOLTS TO 9 VOLTS TRANSFORMER

A transformer is a static device that transfers electrical energy from one circuit to another through inductively coupledconductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field through the secondary winding. This varying magnetic field induces a varying electromotive force (EMF) or "voltage" in the secondary winding. This effect is called mutual induction.

If a load is connected to the secondary, an electric current will flow in the secondary winding and electrical energy will be transferred from the primary circuit through the transformer to the load. In an ideal transformer, the induced voltage in the secondary winding (Vs) is in proportion to the primary voltage (Vp), and is given by the ratio of the number of turns in the secondary (Ns) to the number of turns in the primary (Np) as follows:

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By appropriate selection of the ratio of turns, a transformer thus allows an alternating current (AC) voltage to be "stepped up" by making Ns greater than Np, or "stepped down" by making Ns less than Np.

In the vast majority of transformers, the windings are coils wound around a ferromagnetic core, air-core transformers being a notable exception.

Transformers range in size from a thumbnail-sized coupling transformer hidden inside a stage microphoneto huge units weighing hundreds of tons used to interconnect portions of power grids. All operate with the same basic principles, although the range of designs is wide. While new technologies have eliminated the need for transformers in some electronic circuits, transformers are still found in nearly all electronic devices designed for household ("mains") voltage. Transformers are essential for high-voltage electric power transmission, which makes long-distance transmission economically practical.

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DIODES

In electronics, a diode is a two-terminal electronic componentthat conducts electric current in only one direction. The term usually refers to a semiconductor diode, the most common type today. This is a crystalline piece of semiconductor material connected to two electrical terminals.[1] A vacuum tube diode(now little used except in some high-power technologies) is avacuum tube with two electrodes: a plate and a cathode.

The most common function of a diode is to allow an electric current to pass in one direction (called the diode's forwarddirection) while blocking current in the opposite direction (thereverse direction). Thus, the diode can be thought of as an electronic version of a check valve. This unidirectional behavior is called rectification, and is used to convert alternating current todirect current, and to extract modulation from radio signals in radio receivers.

However, diodes can have more complicated behavior than this simple on-off action. This is due to their complex non-linearelectrical characteristics, which can be tailored by varying the construction of their P-N junction. These are exploited in special purpose diodes that perform many different functions. For example, specialized diodes are used to regulate voltage (Zener diodes), to electronically tune radio and TV receivers (varactor diodes), to generate radio frequency oscillations (tunnel diodes), and to produce light (light emitting diodes). Tunnel diodes exhibitnegative resistance, which makes them useful in some types of circuits.

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Diodes were the first semiconductor electronic devices. The discovery of crystals' rectifying abilities was made by German physicist Ferdinand Braun in 1874. The first semiconductor diodes, called cat's whisker diodes, developed around 1906, were made of mineral crystals such as galena. Today most diodes are made of silicon, but other semiconductors such as germanium are sometimes used.

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RESISTANCE

A resistor is a two-terminal passive electronic component which implements electrical resistance as a circuit element. When a voltage V is applied across the terminals of a resistor, a current I will flow through the resistor in direct proportion to that voltage. This constant of proportionality is called conductance, G. The reciprocal of the conductance is known as the resistance R, since, with a given voltage V, a larger value of R further "resists" the flow of current I as given by 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.

The electrical functionality of a resistor is specified by its resistance: common commercial resistors are manufactured over a range of more than 9 orders of magnitude. When specifying that resistance in an electronic design, the required precision of the resistance may require attention to the manufacturing tolerance of the chosen resistor, according to its specific application. The temperature coefficient of

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the resistance may also be of concern in some precision applications. Practical resistors are also specified as having a maximum power rating which must exceed the anticipated power dissipation of that resistor in a particular circuit: this is mainly of concern in power electronics applications. Resistors with higher power ratings are physically larger and may require heat sinking. In a high voltage circuit, attention must sometimes be paid to the rated maximum working voltage of the resistor.

The series inductance of a practical resistor causes its behavior to depart from ohms law; this specification can be important in some high-frequency applications for smaller values of resistance. In a low-noise amplifier or pre-amp the noise characteristics of a resistor may be an issue. The unwanted inductance, excess noise, and temperature coefficient are mainly dependent on the technology used in manufacturing the resistor. They are not normally specified individually for a particular family of resistors manufactured using a particular technology.[1] A family of discrete resistors is also characterized according to its form factor, that is, the size of the device and position of its leads (or terminals) which is relevant in the practical manufacturing of circuits using them.

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CAPACITOR

A capacitor (formerly known as condenser) is a device for storing electric charge. 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.

The capacitance is greatest when there is a narrow separation between large areas of conductor, hence capacitor conductors are often called "plates", referring to an early means of construction. In practice the

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dielectric between the plates passes a small amount of leakage current and also has an electric field strength limit, resulting in a breakdown voltage, while the conductors and leads introduce an undesired inductance and resistance.

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ELECTROLYTIC CAPACITOR

An electrolytic capacitor is a type of capacitor that uses an electrolyte, an ionic conducting liquid, as one of its plates, to achieve a larger capacitance per unit volume than other types. They are often referred to in electronics usage simply as "electrolytics". They are used in relatively high-current and low-frequency electrical circuits, particularly in power supply filters, where they store charge needed to moderate output voltage and current fluctuations inrectifier output. They are also widely used as coupling capacitors in circuits where AC should be conducted but DC should not. There are two types of electrolytics; aluminum and tantalum.

Electrolytic capacitors are capable of providing the highest capacitance values of any type of capacitor but they have drawbacks which limit their use. The standard design requires that the applied voltage must be polarized; one specified terminal must always have positive potential with respect to the other. Therefore they cannot be used with AC signals without a DC polarizing bias. However there are special non-polarized electrolytic capacitors for AC use which do not require a DC bias. Electrolytic capacitors also have relatively low breakdown voltage, higher leakage current and inductance, poorer tolerances and temperature range, and shorter lifetimes compared to other types of capacitors.

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VOLTAGE REGULATOR

A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. A voltage regulator may be a simple "feed-forward" design or may include negative feedback control loops. It may use an electromechanical mechanism, or electronic components. Depending on the design, it may be used to regulate one or more AC or DC voltages.

Electronic voltage regulators are found in devices such as computer power supplies where they stabilize the DC voltages used by the processor and other elements. In automobile alternators and central power station generator plants, voltage regulators control the output of the plant. In an electric power distribution system, voltage regulators may be installed at a substation or along distribution lines so that all customers receive steady voltage independent of how much power is drawn from the line.

Feedback voltage regulators operate by comparing the actual output voltage to some fixed reference voltage. Any difference is amplified and used to control the regulation element in such a way as to reduce the voltage error. This forms a negative feedback control loop; increasing the open-loop gain tends to increase regulation accuracy but reduce stability (avoidance of oscillation, or ringing during step changes). There will also be a trade-off between stability and the speed of the response to changes. If the output voltage is too low (perhaps due to input voltage reducing or load current increasing), the regulation element is commanded, up to

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a point, to produce a higher output voltage–by dropping less of the input voltage (for linear series regulators and buck switching regulators), or to draw input current for longer periods (boost-type switching regulators); if the output voltage is too high, the regulation element will normally be commanded to produce a lower voltage. However, many regulators have over-current protection, so that they will entirely stop sourcing current (or limit the current in some way) if the output current is too high, and some regulators may also shut down if the input voltage is outside a given range (see also: crowbar circuits).

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PUSH BUTTON

A push-button (also spelled pushbutton) (press-button in the UK) or simply button is a simple switch mechanism for controlling some aspect of a machine or a process. Buttons are typically made out of hard material, usually plastic or metal. The surface is usually flat or shaped to accommodate the human finger or hand, so as to be easily depressed or pushed. Buttons are most often biased switches, though even many un-biased buttons (due to their physical nature) require a spring to return to their un-pushed state. Different people use different terms for the "pushing" of the button, such as press, depress,mash, and punch.

Pushbuttons are often color-coded to associate them with their function so that the operator will not push the wrong button in error. Commonly used colors are red for stopping the machine or process and green for starting the machine or process.

Red pushbuttons can also have large heads (called mushroom heads) for easy operation and to facilitate the stopping of a machine. These pushbuttons are called emergency stopbuttons and are mandated by the electrical code in many jurisdictions for increased safety. This large mushroom shape can also be found in buttons for use with operators who need to wear gloves for their work and could not actuate a regular flush-mountedpush button. As an aid for

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operators and users in industrial or commercial applications, apilot light is commonly added to draw the attention of the user and to provide feedback if the button is pushed. Typically this light is included into the center of the pushbutton and a lens replaces the pushbutton hard center disk. The source of the energy to illuminate the light is not directly tied to the contacts on the back of the pushbutton but to the action the pushbutton controls. In this way a start button when pushed will cause the process or machine operation to be started and a secondary contact designed into the operation or process will close to turn on the pilot light and signify the action of pushing the button caused the resultant process or action to start

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CRYSTAL OSCILLATOR

A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precisefrequency. This frequency is commonly used to keep track of time (as in quartz wristwatches), to provide a stable clock signal for digital integrated circuits, and to stabilize frequencies forradio transmitters and receivers. The most common type of piezoelectric resonator used is thequartz crystal, so oscillator circuits designed around them became known as "crystal oscillators."

Quartz crystals are manufactured for frequencies from a few tens of kilohertz to tens of megahertz. More than two billion (2×109) crystals are manufactured annually. Most are used for consumer devices such as wristwatches, clocks, radios, computers, and cellphones. Quartz crystals are also found inside test and measurement equipment, such as counters,signal generators, and oscilloscopes

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MICROCONTROLLER

A microcontroller (sometimes abbreviated µC, uC or MCU) is a small computer on a single integrated circuit containing a processor core, memory, and programmableinput/output peripherals. Program memory in the form of NOR flash or OTP ROM is also often included on chip, as well as a typically small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to the microprocessors used inpersonal computers or other general purpose applications.

Microcontrollers are used in automatically controlled products and devices, such as automobile engine control systems, implantable medical devices, remote controls, office machines, appliances, power tools, and toys. By reducing the size and cost compared to a design that uses a separate microprocessor, memory, and input/output devices, microcontrollers make it economical to digitally control even more devices and processes. Mixed signal microcontrollers are common, integrating analog components needed to control non-digital electronic systems.

Some microcontrollers may use Four-bit words and operate at clock rate frequencies as low as 4 kHz, for low power consumption (milliwatts or microwatts). They will generally have the ability to retain functionality while waiting for an event such as a button press or other interrupt; power consumption while sleeping (CPU clock and most peripherals off) may be just nanowatts, making many of them well suited for long lasting battery applications. Other microcontrollers may serve

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performance-critical roles, where they may need to act more like a digital signal processor (DSP), with higher clock speeds and power consumption

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8051 architecture

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Pins 1-8: Port 1 Each of these pins can be configured as an input or an output.Pin 9: RS A logic one on this pin disables the microcontroller and clears the contents of most registers. In other words, the positive voltage on this pin resets the microcontroller. By applying logic zero to this pin, the program starts execution from the beginning.Pins10-17: Port 3 Similar to port 1, each of these pins can serve as general input or output. Besides, all of them have alternative functions:Pin 10: RXD Serial asynchronous communication input or Serial synchronous communication output.Pin 11: TXD Serial asynchronous communication output or Serial synchronous communication clock output.Pin 12: INT0 Interrupt 0 input.Pin 13: INT1 Interrupt 1 input.Pin 14: T0 Counter 0 clock input.Pin 15: T1 Counter 1 clock input.Pin 16: WR Write to external (additional) RAM.Pin 17: RD Read from external RAM.Pin 18, 19: X2, X1 Internal oscillator input and output. A quartz crystal which specifies operating frequency is usually connected to these pins. Instead of it, miniature ceramics resonators can also be used for frequency stability. Later versions of microcontrollers operate at a frequency of 0 Hz up to over 50 Hz.Pin 20: GND Ground.Pin 21-28: Port 2 If there is no intention to use external memory then these port pins are configured as general inputs/outputs. In case external memory is used, the higher address byte, i.e. addresses A8-A15 will appear on this port. Even though memory with capacity of 64Kb is not used, which means that not all eight port bits are

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used for its addressing, the rest of them are not available as inputs/outputs.Pin 29: PSEN If external ROM is used for storing program then a logic zero (0) appears on it every time the microcontroller reads a byte from memory.Pin 30: ALE Prior to reading from external memory, the microcontroller puts the lower address byte (A0-A7) on P0 and activates the ALE output. After receiving signal from the ALE pin, the external register (usually 74HCT373 or 74HCT375 add-on chip) memorizes the state of P0 and uses it as a memory chip address. Immediately after that, the ALU pin is returned its previous logic state and P0 is now used as a Data Bus. As seen, port data multiplexing is performed by means of only one additional (and cheap) integrated circuit. In other words, this port is used for both data and address transmission.Pin 31: EA By applying logic zero to this pin, P2 and P3 are used for data and address transmission with no regard to whether there is internal memory or not. It means that even there is a program written to the microcontroller, it will not be executed. Instead, the program written to external ROM will be executed. By applying logic one to the EA pin, the microcontroller will use both memories, first internal then external (if exists).Pin 32-39: Port 0 Similar to P2, if external memory is not used, these pins can be used as general inputs/outputs. Otherwise, P0 is configured as address output (A0-A7) when the ALE pin is driven high (1) or as data output (Data Bus) when the ALE pin is driven low (0).Pin 40: VCC +5V power supply

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8051 INTERFACING:

LED INTERFACING

LEDs are by far the most widely used means of taking output. They find huge application as indicators during experimentations to check the validity of results at different stages. They are very cheap and easily available in a variety of shape, size and colors.The principle of operation of LEDs is simple. The commonly available LEDs have a drop voltage of 1.7 V and need 10 mA to glow at full intensity. The following circuit describes “how to glow an led”.

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The value of resistance R can be calculated using the equation, R= (V-1.7)/10 mA. Since most of the controllers work on 5V, so substituting V= 5V, the value of resistance comes out to be 330 ohm. The resistance 220 ohm, 470 ohm is commonly used substitute in case 330 ohm is not available.

  

AT89C51 is a 40 pin microcontroller which belongs to 8051 series of microcontroller. It has four ports each of 8 bits P0, P1, P2 and P3.The AT89C51 has 4K bytes of programmable flash. The port P0 covers the pin 32 to pin 39, the port P1 covers the pin 1 to pin 8, the port P2 covers the pin 21 to pin 28 and the port P3 covers the pin 10 to pin 17. Pin 9 is the reset pin. The reset is active high. Whenever the controller is given supply, the reset pin must be given a high signal to reset the controller and bring the program counter to the starting address 0x0000. The controller can be reset by manually connecting a switch or by connecting a combination of resistor and capacitor as shown in the circuit diagram. A 12 MHz crystal is connected between pin 18 pin 19. Pin 40 is Vcc and pin 20 is ground. Pin 31, is connected to Vcc as we are using the internal memory of the controller.

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LEDs are connected to the port P0. LEDs need approximately 10mA current to flow through them in order to glow at maximum intensity. However the output of the controller is not sufficient enough to drive the LEDs, so if the positive leg of the LED is connected to the pin and the negative to ground as shown in the figure, the LEDwill not glow at full illumination.

 

To overcome this problem LEDs are connected in the reverse order and they run on negative logic i.e., whenever 1 is given on any pin of the port, the LED will switch off and when logic 0 is provided the LED will glow at full intensity. 

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As soon as we provide supply to the controller, the LEDs start blinking i.e., they become on for a certain time duration and then become off for the same time duration. This delay is provided by calling the delay function. The values inside the delay function have been set to provide a delay in multiples of millisecond (delay (100) will provide a delay of 100 millisecond).

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PROGRAM CODE

ORG 0H

CLR P1.0

AGAIN:

ACALL DELAY

ACALL DELAY

CPL P1.0

ACALL DELAY

ACALL DELAY

SJMP AGAIN

DELAY:

MOV R3, #05Fh

OUTER: MOV R2, #0242

OUTER1:MOV R1, #255

INNER: DJNZ R1, INNER

DJNZ R2,OUTER1

DJNZ R3, OUTER

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RET

END

CIRCUIT DIAGRAM:

5 VOLTS POWER SUPPLY

EXPLANATION

Brief description of operation: Gives out well regulated +5V output, output current capability of 100 mA

Circuit protection: Built-in overheating protection shuts down output when regulator IC gets too hot

Circuit complexity: Very simple and easy to build

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Circuit performance: Very stable +5V output voltage, reliable operation

Availability of components: Easy to get, uses only very common basic components

Design testing: Based on datasheet example circuit, I have used this circuit succesfully as part of many electronics projects

Applications: Part of electronics devices, small laboratory power supply

Power supply voltage: Unreglated DC 8-18V power supply

Power supply current: Needed output current + 5 mA Component costs: Few dollars for the electronics

components + the input transformer cost

Circuit description

This circuit is a small +5V power supply, which is useful when experimenting with digital electronics. Small inexpensive wall tranformers with variable output voltage are available from any electronics shop and supermarket. Those transformers are easily available, but usually their voltage regulation is very poor, which makes then not very usable for digital circuit experimenter unless a better regulation can be achieved in some way. The following circuit is the answer to the problem.

This circuit can give +5V output at about 150 mA current, but it can be increased to 1 A when good cooling is added to 7805 regulator chip. The circuit has over overload and therminal protection.

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 Circuit diagram of the power supply.

The capacitors must have enough high voltage rating to safely handle the input voltage feed to circuit. The circuit is very easy to build for example into a piece of veroboard.

 Pinout of the 7805 regulator IC.

1. Unregulated voltage in 2. Ground 3. Regulated voltage out

Component list7805 regulator IC470 uF electrolytic capacitor, at least 25V voltage rating electrolytic capacitor, at least 6V voltage rating100 nF ceramic or polyester capacitor

Modification ideas

More output current

If you need more than 150 mA of output current, you can update the output current up to 1A doing the following modifications:

Change the transformer from where you take the power to the circuit to a model which can give as much current as you need from output

Put a heatsink to the 7805 regulator (so big that it does not overheat because of the extra losses in the regulator)

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Other output voltages

If you need other voltages than +5V, you can modify the circuit by replacing the 7805 chips with another regulator with different output voltage from regulator 78xx chip family. The last numbers in the the chip code tells the output voltage. Remember that the input voltage muts be at least 3V greater than regulator output voltage ot otherwise the regulator does not work well.

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TOOLS USED:

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 workpieces.

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.

Less common uses include pyrography (burning designs into wood) and plastic welding.

Soldering irons are most often used for installation, repairs and limited production work. High-volume production lines use other soldering methods. [1]

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Connecting wires

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STRIPBOARD

Stripboard is a widely-used type of electronics prototyping board characterized by a 0.1 inch (2.54 mm) regular (rectangular) grid of holes, with wide parallel strips of copper cladding running in one direction all the way across one side of the board. It is usually known by the name Veroboard, which is a trademark, in the UK, of British company Vero Technologies Ltd, & Pixel Print LTD Canada.

In using the board, breaks are made in the tracks, usually around holes, to divide the strips into multiple electrical nodes. With care, it is possible to break between holes to allow for components that have two pin rows only one position apart such as twin row headers for IDCs.

A related product is called perfboard (short for perforated board). This is like a Veroboard but each hole has an isolated copper pad rather than a default pattern of copper tracks. Perfboard is also widely used for electrical prototyping, generally with techniques such as miniature point to point wiring, wire wrapping, or a wiring pencil.

Stripboard is available from many different vendors. All versions have copper strips on one side. Some are made using printed circuit board etching and drilling techniques, although some have milled strips and punched holes. The original Veroboard used FR-2 synthetic-resin-bonded paper (SRBP) (also known as phenolic board) as the base board material. Some versions of stripboard now use higher quality FR-4 (fiberglass-reinforced epoxy laminate) material.[1]

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Stripboard holes are drilled on 0.1 inch (2.54 mm) centers. This spacing allows components having pins with a 0.1 inch (2.54 mm) spacing to be inserted. Compatible parts include DIP ICs, sockets for ICs, some types of connectors, and other devices.

The components are usually placed on the plain side of the board, with their leads protruding through the holes. The leads are then soldered to the copper tracks on the other side of the board to make the desired connections, and any excess wire is cut off. The continuous tracks may be easily and neatly cut as desired to form breaks between conductors using a 5 mm twist drill, a hand cutter made for the purpose, or a knife. Tracks may be linked up on either side of the board using wire. With practice, very neat and reliable assemblies can be created, though such a method is labour-intensive and therefore unsuitable for production assemblies except in very small quantity

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KEIL SOFTWARE

The Keil™ products from ARM include C/C++ compilers, debuggers, integrated environments, RTOS, simulation models, and evaluation boards for ARM, Cortex-M, Cortex-R, 8051, C166, and 251 processor families.

The µVision IDE from Keil combines project management, make facilities, source code editing, program debugging, and complete simulation in one powerful environment. The µVision development platform is easy-to-use and helping you quickly create embedded programs that work. The µVision editor and debugger are integrated in a single application that provides a seamless embedded project development environment.

SUNROM PROGRAMMER

The µVision IDE from Keil combines project management, make facilities, source code editing, program debugging, and complete simulation in one powerful environment. The µVision development platform is easy-to-use and helping you quickly create embedded programs that work. The µVision editor and debugger are integrated in a single application that provides a seamless embedded project development environment.

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Supported DevicesAtmelAT89C51AT89C52

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AT89S51AT89S52AT89S53AT89S8252AT89C1051AT89C2051AT89C4051

WinbondW78E51W78E52

SSTSST89C54SST89C58SST89C59SST89E54RDSST89E58RDSST89E554RC

Serial EEPROMAT24C01AT24C02AT24C04AT24C08AT24C16AT24C32AT24C64AT24C164AT93C46AT93C56AT93C66

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The original programming code for the project:

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Future scope and applications

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Electronic locks offer a variety of means of authentication; those described below are not considered exhaustive.

Numerical codes, passwords and passphrases

Perhaps the most prevalent form of electronic lock is that using a numerical code for authentication; the correct code must be entered in order for the lock to deactivate. Such locks typically provide a keypad, and some feature an audible response to each press. Combination lengths are usually between 4 and 6 digits long.

A variation on this design involves the user entering the correct password or passphrase.

Security tokens

Another means of authenticating users is to require them to scan or "swipe" a security token such as a smart card or similar, or to interact a token with the lock. For example, some locks can access stored credentials on a personal digital assistant (PDA) usinginfrared data transfer methods.

Biometrics

As biometrics become more and more prominent as a recognized means of positive identification, their use in security systems increases. Some new electronic locks take advantage of technologies such as fingerprint scanning, retinal scanning and iris scanning, and voiceprint identification to authenticate users.

RFID

Radio-frequency identification (RFID) is the use of an object (typically referred to as an RFID tag) applied to or

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incorporated into a product, animal, or person for the purpose of identification and tracking using radio waves. Some tags can be read from several meters away and beyond the line of sight of the reader. This technology is also used in modern electronic locks.

This Detector is analogous to Biometrics finger Print

Sensor. It is very helpful in Electronic Locks , Safety

purposes, design locks using different shapes of

metal object, baby toys, radio frequency applied key

locks.

It can replace mechanical locks which use

mechanical methods to get unlocked.

They are less economic as compared to BIOMETRICS

SENSORS.

REFERENCE

1. 8051 Microcontroller by Ali mazidi.

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2. 8051 Architecture By Ayala.3. Wikipedia4. Google images5. www.datasheetcatalog.com6. www.google.com

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