Train Automation Syste

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MICROCONTROLLER BASED TRAIN AUTOMATION SYSTEMUSING SOLAR PANEL

CHAPTER 1

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INTRODUCTION

We know that the railway network of India is the biggest in south Asia and perhaps the most

complicated in all over the world. There are so many different types of trains local, fast, super

fast, passenger, goods. etc. and there so many multiple routs.

In this project we try to give the same prototype for this type of trains. We are using

microcontroller !"# as $%&. The motion of the train is controlled by the '$ (otor, for

displaying message in the train we are using )$' 'isplay of two lines. The train is designed for

two stations, named as &jjain * Indore. The +toppage time is of +ec. There is a )$' display

for showing various messages in the train for passengers. -efore starting at station the train

blows the buer.

Whenever any engine observer an obstacle on its track it will stops automatically the

train. When the obstacle or other trains are removed from the track then train will start and go on.%resent project is designed using !"# microcontroller to avoid railway accidents at the track

when two train are at same track, This project utilies two powerful I/ module0 two pair of I/

module are fi1ed at one train at front and back side of the train and the two pair of I/ module are

used at other train because when the two trains are at same track than the train I/ module

observe the obstacle at track than the train will stop 2motor will stop3.

We are also including automatic gate controller. In this section we are including read

switch 2this is magnetically operated3 are fi1ed at #km on both sides of the gate. When train

arrives at the sensing point alarm is triggered at the railway crossing point so that the people get

intimation that gate is going to be closed and at that time the )$' display the message 45AT6WI)) $)7+64. Then the control system activates and closes the gate on either side of the track.

7nce the train crosses the other end control system automatically lifts the gate and the gate will

open and at that time the )$' display the message 85AT6 WI)) 7%694.

The power supply will provide by the solar energy in the project. We are also used the

solar panel for the power and the train will also run by the solar power. We are also used the

secondary power supply by the battery. When the train will run in night than we use the

secondary power supply.

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WHY WE CHOOSE THIS PROJECT

9ow a day:s public is facing many threats from the railway department by which they are

hesitating to plan a train journey. The main reason for this is due to the accidents that occur due

to negligence of train drivers. Though the railway department is trying to take actions to reduce

such informal things but couldn:t see the face of success. To help out the department we have

designed our system.

We are seen in the railway the many problems are face and the many workers are

re;uired in railway so we design a project according to re;uirement of railway

This project is introduced to railway gate controlling train intelligence. It means we

reduce the accident in the railway because we use the intelligence train. In the intelligence trainwe include the driverless train2in this we defined the two station &jjain and Indore and train will

automatic stop at the station and after some second the train will start and this process run

continuously3 and also the I/ sensor are used. 2This is used to define the obstacle in front of

train3.

This project also provide the time limitation and the main problem in railway is delay the train

"! its also reduced by this project.

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FUTURE SCOPE OF THIS PROJECT

This project is used for developing countries for bright future of countries.

It helps us to control the train without drivers and stations will indicate on )$' so

passenger doesn:t have any difficulty.

The major advantage of this project it avoid the accidents.

These projects reduce the power consumption.

It is increase the technological trends and in this way help the people in many ways.

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CHAPTER 2

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WORKING

We are design the train automation system, we are dividing the project in two section

#. Intelligence train. Automatic gate controller

+o first we e1plain the working of intelligence train, in the intelligence train when the train will

start from the first station 2say &jjain3 at this time the )$' shows the message 8W6)$7(6 T7

I9T6))I569$6 T/AI94 , after some time the motor will start train travel along the track,

again )$' display the message 8967/ T?6 I9$79@I9I69$64 .

The second section is automatic gate controller, in this section the two read switch is placed

along the track and the distance between the gate and read switch is #km. when the train is

contact with read switch than the read switch send the signal to microcontroller and

microcontroller provide the signal according to signal to )B' and its connected to '$ motor

and motor move, close the gate and at that time the )$' display the message 85AT6 WI))$)7+64. The buer also glows at that time. When train is contact with the other end read

switch than at that time the gate will open and the )$' also display the message4 5AT6 WI))

7%694.

This process repeat in our project

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BLOCK DIAGRAM

1. BLOCK DIAGRAM OF INTELLIGENCE TRAIN

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2. BLOCK DIAGRAM OF AUTOMATIC GATE CONTROLLER

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MICRO CONTROLLER P89V51RD2

EAD SWITCH SENSOR

LCD

POWER SUPPLY

BUZZER

DC MOTOR

L292D


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CIRCUIT DIAGRAM

1. CIRCUIT DIAGRAM OF INTELLEGENCE TRAIN

2. CIRCUIT DIAGRAM OF AUTOMATIC GATE CONTROLLER

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PCB LAYOUT:

1. PCB LAYOUT OF INTELLEGENCE SYSTEM

A. TOP VIES OF INTELLIGENCE TRAIN

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B). BOTTOM VIEW OF INTELLIGENCE TRAIN

2. PCB OF AUTOMATIC GATE CONTROLLER

A. TOP VIEW OF AGC

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B. THE BOTTOM VIEW OF AGC

FLOW CHART

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TESTING

A) Har!ar"

#. C#$%&$'&%( %"%

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>irst of all we checked the %$- that all the tracks are as per the design of %$- and

showing continuity with the help of millimeter %$- layout!

. S*#r% +&r+'&% %"%

Then we check the %$- for any unwanted short circuit with the help of millimeter

and %$- layout.

B. S#,"r&$-In the ne1t step, we soldered the re;uired components. And then checked that there

are no any unwanted short occurred due to soldering without putting I$:s and keeping

power supply off.B) P#!"r ',( %"%

In the ne1t step, we put power supply on and checked whether re;uired voltage is

appearing at the re;uired voltage is appearing at the re;uired points ie.C@cc and 59'

at respective points. We took care of not connecting I$:s in the circuit whileperforming this test.

C) M&+r#+#$%r#,,"r %"%

>or testing the microcontroller, we wrote the s;uare wave generation program for

generating s;uare wave on each port pin. Then we fed the program in micron roller

and checked the output with the help of $/7 by connecting the microcontroller in the

circuit. We took care of not connecting any other I$ in the circuit.

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CHAPTER /

RESISTOR

A resistor is apassivetwoDterminalelectrical componentthat implements electrical resistanceasa circuit element.

The currentthrough a resistor is in direct proportionto the voltageacross the resistorEs terminals.This relationship is represented by 7hmEs lawF

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Where Iis the current through the conductorin units of amperes, V is the potential differencemeasured across the conductor in units of volts, and Ris the resistance of the conductor in unitsof ohms.

The ratio of the voltage applied across a resistorEs terminals to the intensity of current in thecircuit is called its resistance, and this can be assumed to be a constant 2independent of thevoltage3 for ordinary resistors working within their ratings.

E,"+%r#$&+ (0#, a$ $#%a%$

The symbol used for a resistor in a circuit diagramvaries from standard to standard and country

to country. Two typical symbols are as follows0

AmericanDstyle symbols. 2a3 /esistor, 2b3 rheostat 2variable resistor3, and

2c3 potentiometer

I6$Dstyle resistor symbol

The notation to state a resistorEs value in a circuit diagram varies, too. The 6uropean notation

avoids using a decimal separator, and replaces the decimal separator with the +I prefi1 symbol

for the particular value. >or e1ample, 8k2 in a circuit diagram indicates a resistor value of

. kG. Additional eros imply tighter tolerance, for e1ample 15M0. When the value can be

e1pressed without the need for an +I prefi1, an E/E is used instead of the decimal separator. >or

e1ample, 1R2indicates #. G, and 18Rindicates # G. The use of a +I prefi1 symbol or the letter

E/E circumvents the problem that decimal separators tend to EdisappearE when photocopying a

printed circuit diagram.

T*"#r( # #"ra%$

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The hydraulic analogycompares electric current flowing through circuits to water flowing through pipes.

When a pipe 2left3 is filled with hair 2right3, it takes a larger pressure to achieve the same flow of water.

%ushing electric current through a large resistance is like pushing water through a pipe clogged with hairF

It re;uires a larger push 2voltage drop3 to drive the same flow 2electric current3.

L"a arra$-"0"$%

ThroughDholecomponents typically have leads leaving the body a1ially. 7thers have leads

coming off their body radials instead of parallel to the resistor a1is. 7ther components may be

+(T 2surface mount technology3 while high power resistors may have one of their leads

designed into the heat sink.

T*" S%a$ar EIA C#,#r C#" Ta," "r EIA3RS3245 & a #,,#!:

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$olor#st

band

nd

band

Brd band

2multiplier3

Hth band

2tolerance3

Temp.

$oefficient

-lack ! ! #!!

-rown # # #!# J#K 2>3 #!! ppm

/ed #! JK 253 "! ppm

7rang

eB B #!B #" ppm

=ellow H H #!H " ppm

5reen " " #!" J!."K 2'3

-lue L L #!L J!."K 2$3

@iolet M M #!M J!.#K 2-3

5ray #! J!.!"K 2A3

White #!

5old !.# J"K 2N3

+ilver !.!# J#!K 2O3

CAPACITOR

A capacitor 2originally known as condenser3 is apassivetwoDterminalelectrical componentused

to store energyin anelectric field. The forms of practical capacitors vary widely, but all contain

at least two electrical conductorsseparated by a dielectric2insulator30 for e1ample, one common

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construction consists of metal foils separated by a thin layer of insulating film. $apacitors are

widely used as parts of electrical circuitsin many common electrical devices.

When there is a potential difference 2voltage3 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. 6nergyis stored in the electrostatic field. An ideal capacitor is characteried

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.

The capacitance is greatest when there is a narrow separation between large areas of conductor0

hence capacitor conductors are often called plates, referring to an early means of construction. In

practice, the dielectric between the plates passes a small amount of leakage currentand also has

an electric field strength limit, resulting in abreakdown voltage, while the conductors and leads

introduce an undesired inductanceandresistance.

$apacitors are widely used in electronic circuits for blocking direct current while allowing

alternating currentto pass, in filter networks, for smoothing the output of power supplies, in the

resonant circuitsthat tune radios to particular fre;uencies,in electric power transmission systems

for stabiliing voltage and power flow, and for many other purposes.

T*"#r( # #"ra%$

$harge separation in a parallelDplate capacitor causes an internal electric field. A dielectric

2orange3 reduces the field and increases the capacitance .

A simple demonstration of a parallelDplate capacitor

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A capacitor consists of two conductors separated by a nonDconductive region.P#!Q The nonD

conductive region is called the dielectric. In simpler terms, the dielectric is just an electrical

insulator. 61amples of dielectric media are glass, air, paper, vacuum, and even a semiconductor

depletion regionchemically identical to the conductors. A capacitor is assumed to be selfDcontained and isolated, with no net electric chargeand no influence from any e1ternal electric

field. The conductors thus hold e;ual and opposite charges on their facing surfaces, P##Qand the

dielectric develops an electric field. In +I units, a capacitance of one faradmeans that one

coulombof charge on each conductor causes a voltage of one voltacross the device.P#Q

The capacitor is a reasonably general model for electric fields within electric circuits. An ideal

capacitor is wholly characteried by a constant capacitance C, defined as the ratio of charge JQ

on each conductor to the voltage Vbetween themFP#!Q

+ometimes charge buildDup affects the capacitor mechanically, causing its capacitance to vary. In

this case, capacitance is defined in terms of incremental changesF

A,&+a%$

6nergy storageF

P"#$%& '()%* +,& )%+'(,$

%ower conditioningF

TRANSISTOR

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A transistor is a semiconductor device used to amplify and switch electronic signals and

electrical power. It is composed of semiconductor material with at least three terminals for

connection to an e1ternal circuit. A voltage or current applied to one pair of the transistorEs

terminals changes the current through another pair of terminals. -ecause the controlled 2output3powercan be higher than the controlling 2input3 power, a transistor can amplifya signal. Today,

some transistors are packaged individually, but many more are found embedded in integrated

circuits.

The transistor is the fundamental building block of modern electronic devices,and is ubi;uitous

in modern electronic systems. >ollowing its development in the early #"!s, the transistor

revolutionied the field of electronics, and paved the way for smaller and cheaper radios,

calculators, and computers,among other things.

O"ra%$

A simple circuit diagram to show the labels of a 9%9 bipolar transistor.

The essential usefulness of a transistor comes from its ability to use a small signal appliedbetween one pair of its terminals to control a much larger signal at another pair of terminals. This

property is calledgain.A transistor can control its output in proportion to the input signal0 that is,

it can act as an amplifier. Alternatively, the transistor can be used to turn current on or off in a

circuit as an electrically controlled switch, where the amount of current is determined by other

circuit elements.

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There are two types of transistors, which have slight differences in how they are used in a circuit.

Abipolar transistorhas terminals labeled a", +#,,"+%#r, and "0&%%"r. A small current at the

base terminal 2that is, flowing between the base and the emitter3 can control or switch a much

larger current between the collector and emitter terminals. >or a fieldDeffect transistor, theterminals are labeled -a%", #'r+", and ra&$, and a voltage at the gate can control a current

between source and drain. The image to the right represents a typical bipolar transistor in a

circuit. $harge will flow between emitter and collector terminals depending on the current in the

base. +ince internally the base and emitter connections behave like a semiconductor diode, a

voltage drop develops between base and emitter while the base current e1ists. The amount of this

voltage depends on the material the transistor is made from, and is referred to as V-6.

A,&+a%$

#3 Transistor as a switch

3 Transistor as an amplifierF

A6a$%a-"

The key advantages that have allowed transistors to replace their vacuum tube predecessors in

most applications are

9o power consumption by a cathode heater.

+mall sie and minimal weight, allowing the development of miniaturied electronicdevices.

)ow operating voltages compatible with batteries of only a few cells.

9o warmDup period for cathode heaters re;uired after power application.

)ower power dissipation and generally greater energy efficiency.

?igher reliability and greater physical ruggedness.

61tremely long life. +ome transistoried devices have been in service for more than "!

years.

$omplementary devices available, facilitating the design of complementaryDsymmetry

circuits, something not possible with vacuum tubes.

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Insensitivity to mechanical shock and vibration, thus avoiding the problem of micro

phonicsin audio applications.

LIGHT EMITTING DIODE

A lightDemitting diode2)6'3 is a semiconductorlight source. )6's are used as indicator lamps

in many devices and are increasingly used for other lighting. Appearing as practical electroniccomponents in #L, early )6's emitted lowDintensity red light, but modern versions are

available across the visible, ultraviolet,andinfraredwavelengths, with very high brightness.

When a lightDemitting diode is switched on, electronsare able to recombine with electron holes

within the device, releasing energy in the form of photons. This effect is called

electroluminescenceand the color of the light 2corresponding to the energy of the photon3 is

determined by the energy gap of the semiconductor. An )6' is often small in area 2less than

# mm3, and integrated optical components may be used to shape its radiation pattern. )6's

present many advantages over incandescent light sources including lower energy consumption,

longer lifetime, improved physical robustness, smaller sie, and faster switching. ?owever,)6's powerful enough for room lighting are relatively e1pensive and re;uire more precise

current and heat management than compact fluorescent lampsources of comparable output.

)ightDemitting diodes are used in applications as diverse as aviation lighting, automotive

lighting, advertising, general lighting, and traffic signals. )6's have allowed new te1t, video

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

advanced communications technology. Infrared )6's are also used in the remote control units of

many commercial products including televisions, '@' players and other domestic appliances.

)6's are also used in sevenDsegment display.

T"+*$#,#-(

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http://en.wikipedia.org/wiki/Microphonicshttp://en.wikipedia.org/wiki/Microphonicshttp://en.wikipedia.org/wiki/Semiconductor_diodehttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Visible_spectrumhttp://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Electronshttp://en.wikipedia.org/wiki/Photonhttp://en.wikipedia.org/wiki/Electroluminescencehttp://en.wikipedia.org/wiki/Radiation_patternhttp://en.wikipedia.org/wiki/Fluorescent_lamphttp://en.wikipedia.org/wiki/Fluorescent_lamphttp://en.wikipedia.org/wiki/Navigation_light#Aviation_navigation_lightshttp://en.wikipedia.org/wiki/Navigation_light#Aviation_navigation_lightshttp://en.wikipedia.org/wiki/Automotive_lighting#Light_emitting_diodes_.28LED.29http://en.wikipedia.org/wiki/Automotive_lighting#Light_emitting_diodes_.28LED.29http://en.wikipedia.org/wiki/Traffic_signalhttp://en.wikipedia.org/wiki/Seven-segment_displayhttp://en.wikipedia.org/wiki/Seven-segment_displayhttp://en.wikipedia.org/wiki/Microphonicshttp://en.wikipedia.org/wiki/Microphonicshttp://en.wikipedia.org/wiki/Semiconductor_diodehttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Visible_spectrumhttp://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Electronshttp://en.wikipedia.org/wiki/Photonhttp://en.wikipedia.org/wiki/Electroluminescencehttp://en.wikipedia.org/wiki/Radiation_patternhttp://en.wikipedia.org/wiki/Fluorescent_lamphttp://en.wikipedia.org/wiki/Navigation_light#Aviation_navigation_lightshttp://en.wikipedia.org/wiki/Automotive_lighting#Light_emitting_diodes_.28LED.29http://en.wikipedia.org/wiki/Automotive_lighting#Light_emitting_diodes_.28LED.29http://en.wikipedia.org/wiki/Traffic_signalhttp://en.wikipedia.org/wiki/Seven-segment_display


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>ig.# The inner workings of an )6'

>ig. ID@ diagram for adiode. An )6' will begin to emit light when the onDvoltageis e1ceeded. Typical

on voltages are RBvolts.

C#,#r a$ 0a%"r&a,

$onventional )6's are made from a variety of inorganic semiconductor materials. The

following table shows the available colors with wavelength range, voltage drop and materialF

C#,#rWa6","$-%*

7$08

V#,%a-" r#

79V8S"0&+#$'+%#r 0a%"r&a,

Infrared S ML! VU #.LB5allium arsenide 25aAs3

Aluminum gallium arsenide2Al5aAs3

/ed L#! U U ML! #.LB U VU .!B

Aluminum gallium arsenide 2Al5aAs3

5allium arsenide phosphide 25aAs%3

Aluminum gallium indium phosphide 2Al5aIn%3

5allium2III3 phosphide25a%3

7range "! U U L#! .!B U VU .#!


Aluminium gallium indium phosphide 2Al5aIn%3

5allium2III3 phosphide25a%3

=ellow "M! U U "! .#! U VU .#


Aluminium gallium indium phosphide 2Al5aIn%35allium2III3 phosphide25a%3

5reen "!! U U "M! #.P"QU VU H.! Indium gallium nitride 2In5a93 V 5allium2III3

nitride 25a93

5allium2III3 phosphide 25a%3

Aluminium gallium indium phosphide 2Al5aIn%3

26
http://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Volthttp://en.wikipedia.org/wiki/Volthttp://en.wikipedia.org/wiki/Semiconductor_materialshttp://en.wikipedia.org/wiki/Semiconductor_materialshttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Voltage_drophttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Delta_(letter)http://en.wikipedia.org/wiki/Gallium_arsenidehttp://en.wikipedia.org/wiki/Gallium_arsenidehttp://en.wikipedia.org/wiki/Aluminium_gallium_arsenidehttp://en.wikipedia.org/wiki/Redhttp://en.wikipedia.org/wiki/Aluminium_gallium_arsenidehttp://en.wikipedia.org/wiki/Aluminium_gallium_arsenidehttp://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Orange_(color)http://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Yellowhttp://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Greenhttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-59http://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Gallium(III)_nitridehttp://en.wikipedia.org/wiki/Gallium(III)_nitridehttp://en.wikipedia.org/wiki/Gallium(III)_nitridehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Volthttp://en.wikipedia.org/wiki/Semiconductor_materialshttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Voltage_drophttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Delta_(letter)http://en.wikipedia.org/wiki/Gallium_arsenidehttp://en.wikipedia.org/wiki/Aluminium_gallium_arsenidehttp://en.wikipedia.org/wiki/Redhttp://en.wikipedia.org/wiki/Aluminium_gallium_arsenidehttp://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Orange_(color)http://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Yellowhttp://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Greenhttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-59http://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Gallium(III)_nitridehttp://en.wikipedia.org/wiki/Gallium(III)_nitridehttp://en.wikipedia.org/wiki/Gallium(III)_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphide


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Aluminium gallium phosphide2Al5a%3

-lue H"! U U "!! .H U VU B.M

inc selenide 2n+e3

Indium gallium nitride 2In5a93

+ilicon carbide 2+i$3 as substrate+ilicon2+i3 as substrateXunder development

@iolet H!! U U H"! .ML U VU H.! Indium gallium nitride2In5a93

%urple multiple types .H U VU B.M

'ual blueVred )6's,

blue with red phosphor,

or white with purple plastic

&ltravioletU H!! B.# U VU H.H

'iamond 2B" nm3PL!Q

-oron nitride 2#" nm3PL#QPLQ

Aluminium nitride 2Al93 2#! nm3PLBQ

Aluminium gallium nitride 2Al5a93

Aluminium gallium indium nitride 2Al5aIn93X

down to #! nmPLHQ

%ink multiple types VY B.BPL"Q

-lue with one or two phosphor layersF

yellow with red, orange or pink phosphor added

afterwards,

or white with pink pigment or dye.PLLQ

White-road

spectrumVZ B." -lueV&@ diode with yellow phosphor

A,&+a%$

>lashing )6's are used as attention seeking indicators without re;uiring e1ternal electronics. >lashing

)6's resemble standard )6's but they contain an integrated multivibrator circuit that causes the )6' to

flash with a typical period of one second. In diffused lens )6's this is visible as a small black dot. (ost

flashing )6's emit light of one color, but more sophisticated devices can flash between multiple colors

and even fade through a color se;uence using /5- color mi1ing.

-iDcolor )6's are two different )6' emitters in one case. There are two types of these. 7ne

type consists of two dies connected to the same two leads ant parallelto each other. $urrent flowin one direction emits one color, and current in the opposite direction emits the other color. Theother type consists of two dies with separate leads for both dies and another lead for commonanode or cathode, so that they can be controlled independently.

TriDcolor )6'sare three different )6' emitters in one case. 6ach emitter is connected to aseparate lead so they can be controlled independently. A fourDlead arrangement is typical with onecommon lead 2anode or cathode3 and an additional lead for each color.

27
http://en.wikipedia.org/wiki/Aluminium_gallium_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_phosphidehttp://en.wikipedia.org/wiki/Bluehttp://en.wikipedia.org/wiki/Zinc_selenidehttp://en.wikipedia.org/wiki/Zinc_selenidehttp://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Silicon_carbidehttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Violet_(color)http://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Purplehttp://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-dia-60http://en.wikipedia.org/wiki/Boron_nitridehttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-BN-61http://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-bn2-62http://en.wikipedia.org/wiki/Aluminium_nitridehttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-aln-63http://en.wikipedia.org/wiki/Aluminium_gallium_nitridehttp://en.wikipedia.org/w/index.php?title=Aluminium_gallium_indium_nitride&action=edit&redlink=1http://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-64http://en.wikipedia.org/wiki/Pinkhttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-65http://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-66http://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-66http://en.wikipedia.org/wiki/Multivibratorhttp://en.wikipedia.org/wiki/Antiparallel_(electronics)http://en.wikipedia.org/wiki/Antiparallel_(electronics)http://en.wikipedia.org/wiki/Aluminium_gallium_phosphidehttp://en.wikipedia.org/wiki/Bluehttp://en.wikipedia.org/wiki/Zinc_selenidehttp://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Silicon_carbidehttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Violet_(color)http://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Purplehttp://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-dia-60http://en.wikipedia.org/wiki/Boron_nitridehttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-BN-61http://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-bn2-62http://en.wikipedia.org/wiki/Aluminium_nitridehttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-aln-63http://en.wikipedia.org/wiki/Aluminium_gallium_nitridehttp://en.wikipedia.org/w/index.php?title=Aluminium_gallium_indium_nitride&action=edit&redlink=1http://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-64http://en.wikipedia.org/wiki/Pinkhttp://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-65http://en.wikipedia.org/wiki/Light-emitting_diode#cite_note-66http://en.wikipedia.org/wiki/Multivibratorhttp://en.wikipedia.org/wiki/Antiparallel_(electronics)


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/5- )6'sare TriDcolor )6's with red, green, and blue emitters, in general using a fourDwireconnection with one common lead 2anode or cathode3. These )6's can have either commonpositive or common negative leads. 7thers however, have only two leads 2positive and negative3and have a built in tiny electronic control unit.

Alphanumeric )6' displays are available in sevenDsegment and starburst format. +evenDsegment displays handle all numbers and a limited set of letters. +tarburst displays can display allletters. +evenDsegment )6' displays were in widespread use in the #M!s and #!s, but risinguse of #-."-& crystal display with their lower power needs and greater display fle1ibility, hasreduced the popularity of numeric and alphanumeric )6' displays.

DIODE

In electronics, a diode is a twoDterminal electronic component with an asymmetric transfer

characteristic, with low 2ideally ero3 resistance to current flow in one direction, and high

2ideally infinite3 resistance in the other. A semiconductor diode, the most common type today, isa crystallinepiece of semiconductormaterial with a pDn junctionconnected to two electrical

terminals. A vacuum tube diode is a vacuum tubewith twoelectrodes, aplate2anode3 and heated

cathode.

The most common function of a diode is to allow an electric current to pass in one direction

2called the diodeEs forward direction3, while blocking current in the opposite direction 2the

reverse direction3. Thus, the diode can be viewed as an electronic version of a check valve. This

unidirectional behavior is called rectification, and is used to convert alternating currentto direct

current, including e1traction of modulationfrom radio signals in radio receiversXthese diodes

are forms of rectifiers.

?owever, diodes can have more complicated behavior than this simple onRoff action.

+emiconductor diodes begin conducting electricity only if a certain threshold voltage or cutDin

voltage is present in the forward direction 2a state in which the diode is said to be forwardD

biased3. The voltage drop across a forwardDbiased diode varies only a little with the current, and

is a function of temperature0 this effect can be used as a temperature sensororvoltage reference.

+emiconductor diodesE nonlinear currentRvoltage characteristic can be tailored by varying the

semiconductor materials and doping, introducing impurities into the materials. These are

e1ploited in specialDpurpose diodes that perform many different functions. >or e1ample, diodes

are used to regulate voltage 2ener diodes3, to protect circuits from high voltage surges

2avalanche diodes3, to electronically tune radio and T@ receivers 2varactor diodes3, to generate

radio fre;uencyoscillations2tunnel diodes,5unn diodes, I(%ATT diodes3, and to produce light

2light emitting diodes3. Tunnel diodes e1hibit negative resistance, which makes them useful in

some types of circuits.

28
http://en.wikipedia.org/wiki/Electronic_control_unithttp://en.wikipedia.org/wiki/Seven-segment_displayhttp://en.wikipedia.org/wiki/Seven-segment_displayhttp://en.wikipedia.org/wiki/Starburst_displayhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Transfer_characteristichttp://en.wikipedia.org/wiki/Transfer_characteristichttp://en.wikipedia.org/wiki/Electrical_resistance_and_conductancehttp://en.wikipedia.org/wiki/Infinityhttp://en.wikipedia.org/wiki/Crystallinehttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/P-n_junctionhttp://en.wikipedia.org/wiki/Vacuum_tubehttp://en.wikipedia.org/wiki/Electrodehttp://en.wikipedia.org/wiki/Electrodehttp://en.wikipedia.org/wiki/Plate_electrodehttp://en.wikipedia.org/wiki/Plate_electrodehttp://en.wikipedia.org/wiki/Check_valvehttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Modulationhttp://en.wikipedia.org/wiki/Rectifierhttp://en.wikipedia.org/wiki/Rectifierhttp://en.wikipedia.org/wiki/P%E2%80%93n_junction#Forward_biashttp://en.wikipedia.org/wiki/P%E2%80%93n_junction#Forward_biashttp://en.wikipedia.org/wiki/Diode#Temperature_measurementshttp://en.wikipedia.org/wiki/Voltage_referencehttp://en.wikipedia.org/wiki/Voltage_referencehttp://en.wikipedia.org/wiki/Semiconductor_materialshttp://en.wikipedia.org/wiki/Doping_(semiconductor)http://en.wikipedia.org/wiki/Doping_(semiconductor)http://en.wikipedia.org/wiki/Zener_diodehttp://en.wikipedia.org/wiki/Avalanche_diodehttp://en.wikipedia.org/wiki/Varactor_diodehttp://en.wikipedia.org/wiki/Radio_frequencyhttp://en.wikipedia.org/wiki/Radio_frequencyhttp://en.wikipedia.org/wiki/Oscillationhttp://en.wikipedia.org/wiki/Tunnel_diodehttp://en.wikipedia.org/wiki/Tunnel_diodehttp://en.wikipedia.org/wiki/Gunn_diodehttp://en.wikipedia.org/wiki/IMPATT_diodehttp://en.wikipedia.org/wiki/Light_emitting_diodehttp://en.wikipedia.org/wiki/Negative_resistancehttp://en.wikipedia.org/wiki/Electronic_control_unithttp://en.wikipedia.org/wiki/Seven-segment_displayhttp://en.wikipedia.org/wiki/Starburst_displayhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Transfer_characteristichttp://en.wikipedia.org/wiki/Transfer_characteristichttp://en.wikipedia.org/wiki/Electrical_resistance_and_conductancehttp://en.wikipedia.org/wiki/Infinityhttp://en.wikipedia.org/wiki/Crystallinehttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/P-n_junctionhttp://en.wikipedia.org/wiki/Vacuum_tubehttp://en.wikipedia.org/wiki/Electrodehttp://en.wikipedia.org/wiki/Plate_electrodehttp://en.wikipedia.org/wiki/Check_valvehttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Modulationhttp://en.wikipedia.org/wiki/Rectifierhttp://en.wikipedia.org/wiki/P%E2%80%93n_junction#Forward_biashttp://en.wikipedia.org/wiki/P%E2%80%93n_junction#Forward_biashttp://en.wikipedia.org/wiki/Diode#Temperature_measurementshttp://en.wikipedia.org/wiki/Voltage_referencehttp://en.wikipedia.org/wiki/Semiconductor_materialshttp://en.wikipedia.org/wiki/Doping_(semiconductor)http://en.wikipedia.org/wiki/Zener_diodehttp://en.wikipedia.org/wiki/Avalanche_diodehttp://en.wikipedia.org/wiki/Varactor_diodehttp://en.wikipedia.org/wiki/Radio_frequencyhttp://en.wikipedia.org/wiki/Oscillationhttp://en.wikipedia.org/wiki/Tunnel_diodehttp://en.wikipedia.org/wiki/Gunn_diodehttp://en.wikipedia.org/wiki/IMPATT_diodehttp://en.wikipedia.org/wiki/Light_emitting_diodehttp://en.wikipedia.org/wiki/Negative_resistance


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'iodes were the first semiconductor electronic devices. The discovery of crystalsE rectifying

abilities was made by 5erman physicist >erdinand -raun in #MH. The first semiconductor

diodes, called catEs whisker diodes, developed around #!L, were made of mineral crystals such

as galena. Today most diodes are made of silicon, but other semiconductorssuch as germaniumare sometimes used.

BUER

A buer or beeper is an audio signaling device, which may be mechanical, electromechanical, orpieoelectric. Typical uses of buers and beepers include alarm devices, timers andconfirmation of user input such as a mouse click or keystroke.-uer 26lectromagnetic3 " volt D Active -uer F %ieo -uer 2%$- mountable3

G"$"ra, D"+r&%$

5ood performance, general purpose pieo buer used commonly in alerting V alarming circuits.

This is a %$- mountable buer can be easily soldered to %$- board. (ost commonly used in at"v. )ong life, stable performance, ?igh [uality with +7T plastic package

S"+&&+a%$

29
http://en.wikipedia.org/wiki/Semiconductor_devicehttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Ferdinand_Braunhttp://en.wikipedia.org/wiki/Cat's_whisker_diodehttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Germaniumhttp://en.wikipedia.org/wiki/Semiconductor_devicehttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Ferdinand_Braunhttp://en.wikipedia.org/wiki/Cat's_whisker_diodehttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Germanium


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@oltage F H D @'$

(a1imum current F B!mAV"@'$

'ecibel F S "dbV#!cm /esonant fre;uency F "!!? 2CVD B!! ?3

7perating Temperature F D! to M! $

F"a%'r"

%ieo -uers D %$- (ount A #@ dc buer re;uiring no e1ternal oscillation circuit.

The buer has a black A-+ case and %$- pins.

'iameter, e1ternal D Bmm

>re;uency, resonant D BB!!?

+ound level +%) D Md-

$enters, fi1ing D M."mm

$urrent, ma1 D #"mA

)ength V ?eight, e1ternal D #Lmm

%itch, lead D #"mm

Termination Type D +(' @oltage, supply '$ D #@

Pr"+a'%$ #r '"

'o not apply '$ bias to the pieoelectric buer0 otherwise insulation resistance may

become low and affect the performance.

'o not supply any voltage higher than applicable to the pieoelectric buer.

'o not use the pieoelectric buer outdoors. It is designed for indoor use.

If the pieoelectric buer has to be used outdoors, provide it with waterproofing

measures0 it will not operate normally if subjected to moisture. 'o not wash the pieoelectric buer with solvent or allow gas to enter it while washing0

any solvent that enters it may stay inside a long time and damage it.

A pieoelectric ceramic material of appro1imately #!!\m thick is used in the sound

generator of the buer. 'o not press the sound generator through the sound release holeotherwise the ceramic material may break. 'o not stack the pieoelectric buers withoutpacking.

3


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'o not apply any mechanical force to the pieoelectric buer0 otherwise the case may

deform and result in improper operation.

'o not place any shielding material or the like just in front of the sound release hole of

the buer0 otherwise the sound pressure may vary and result in unstable bueroperation. (ake sure that the buer is not affected by a standing wave or the like.

-e sure to solder the buer terminal at B"!]$ ma1.2!W ma1.32soldering iron trip3

within " seconds using a solder containing silver.

Avoid using the pieoelectric buer for a long time where any corrosive gas 2?+, etc.3

e1ists0 otherwise the parts or sound generator may corroded and result in improperoperation.

-e careful not to drop the pieoelectric buer.

READ SWITCH

The basic reed switch consists of two identical flattened ferromagnetic reeds, sealed in a dryinertDgas atmosphere within a glass capsule, thereby protecting the contact from contamination.The reeds are sealed in the capsule in cantilever form so that their free ends overlap and areseparated by a small air gap

H#! #" a r"" !&%+* !#r;" r",a(

A polaried relay placed the armature between the poles of a permanent magnet to increasesensitivity. %olaried relays were used in middle !th $entury telephone e1changes to detectfaint pulses and correct telegraphic distortion. The poles were on screws, so a technician couldfirst adjust them for ma1imum sensitivity and then apply a bias spring to set the critical currentthat would operate the relay.

Ma+*&$" %##, r",a(

A machine tool relay is a type standardied for industrial control of machine tools, transfermachines, and other se;uential control. They are characteried by a large number of contacts2sometimes e1tendable in the field3 which are easily converted from normallyDopen to normallyDclosed status, easily replaceable coils, and a form factor that allows compactly installing manyrelays in a control panel.

IR3SENSOR

A +ensor can be understood as an electrical device which tries to imitate human senses toperform different functions in an electronic circuit. >or e1ample, light sensor helps understandthe intensity of light just like our eyes0 ?eat sensor helps us know the temperature andsimilarly pressure sensor, sound sensor. )et us start with a )ight sensor

A )ight sensor is basically a transmitter receiver pair in which the transmitter transmitselectromagnetic radiation in the form of waves and these waves upon reflection or directtransmission are received by the receiver. -ased on the different types of electromagnetic

36
http://en.wikipedia.org/wiki/Reed_relayhttp://en.wikipedia.org/wiki/Reed_switchhttp://en.wikipedia.org/wiki/Vacuumhttp://en.wikipedia.org/wiki/Inert_gashttp://en.wikipedia.org/wiki/Corrosionhttp://en.wikipedia.org/wiki/Mercury_(element)http://en.wikipedia.org/wiki/Crossbar_switchhttp://en.wikipedia.org/wiki/Distortion#Teletypewriter_or_modem_signalinghttp://en.wikipedia.org/wiki/Designhttp://en.wikipedia.org/wiki/Reed_relayhttp://en.wikipedia.org/wiki/Reed_switchhttp://en.wikipedia.org/wiki/Vacuumhttp://en.wikipedia.org/wiki/Inert_gashttp://en.wikipedia.org/wiki/Corrosionhttp://en.wikipedia.org/wiki/Mercury_(element)http://en.wikipedia.org/wiki/Crossbar_switchhttp://en.wikipedia.org/wiki/Distortion#Teletypewriter_or_modem_signalinghttp://en.wikipedia.org/wiki/Design


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radiation used we have different types of sensors. The most widely used sensor among them isthe Infrared 2I/3 sensor

T*" a&+ &a-ra0 # IR "$#r

The ir sensor pair typically consists of an I/ transmitter and receiver pair. The I/ transmitter isan led that emits light in the infra red region of light spectrum. ?ence the emitterEs light cannot

be seen by naked eye. The ir receiver is a diode constructed in such a way that when the diode isreverse biased ,their light falling on the depleted region causes creation of electronDhole pair andthus this generated pair constitutes current. Thus the current flowing is proportional to ir lightfalling on it.

The emitter is forward biased with a resistor connected in series to limit the current flowingthrough it, the receiver is reverse biased with a resistor of order of #!Es of kilo ohms2#! k ohms isthe best3, to detect the possible voltage change.

Thus the value of voltage at the voltage divider formed on the receiver side varies with the I/light falling on it. A white surface reflects almost all the light focused on it, and a black surface

absorbs all the light focused on it. so depending upon the surface on which the sensor pair isfacing, different voltage is obtained at the output of receiver section.

Infrared radiation is the portion of electromagnetic spectrum having wavelengths longer thanvisible light wavelengths, but smaller than microwaves, i.e., the region roughly from !.M"_m to#!!! _m is the infrared region. Infrared waves are invisible to human eyes. The wavelengthregion of !.M"_m to B _m is called near infrared, the region from B _m to L _m is called midinfrared and the region higher than L _m is called far infrared. 2The demarcations are not rigid0

37


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regions are defined differently by many3. The wavelength of I/ wave is M!! nm to # mm,fre;uency is HB! T? to B!!5? and photon energy is #.H mev to #.M ev

T(" # &$rar" "$#r

A+%&6" &$rar" "$#r

Active infrared sensors employ both infrared source and infrared detectors. They operate bytransmitting energy from either a light emitting diode 2)6'3 or a laser diode. A )6'is used fora nonDimaging active I/ detector, and a laser diode is used for an imaging active I/ detector.In this types of IR "$#r, the )6' or laser diode illuminates the target, and the reflectedenergy is focused onto a detector. %hotoelectric cells, %hotodiode or phototransistors aregenerally used as detectors. The measured data is then processed using various signalDprocessingalgorithms to e1tract the desired information.

Active I/ detectors provide count, presence, speed, and occupancy data in both night and day

operation. The laser diode type can also be used for target classification because it providestarget profile and shape data.These sensors are used as reflective optoDsensors. /eflective optoDsensors are either intensitybased or use modulated I/. Intensity based sensors are affected by ambient light. (odulatedInfrared sensors wherein emitter is turned 79 and 7>> rapidly, are less susceptible to ambientlight. /eflective optoDsensors are used in two configurations.

1. Br"a; B"a0 S"$#r

This type of sensors consists of a pair of light emitting and light detecting elements. Infrared

source transmits a beam of light towards a remote I/ receiver creating an 8electronic fence4.7nce a beam is brokenVinterrupted due to some opa;ue object, output of detector changes andassociated electronic circuitry takes appropriate actions.Typical applications of such sensors are intrusion detection, shaft encoder 2for measurement ofrotation angleVrate of rotation3

2. R","+%a$+" S"$#r

This type of sensors house both an I/ source and an I/ detector in a single housing in such away that light from emitter )6' bounces off an e1ternal object and is reflected into a detector.Amount of light reflected into the detector depends upon the reflectivity of the surface.

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This principle is used in intrusion detection, object detection 2measure the presence of an objectin the sensor:s >7@3, barcode decoding, and surface feature detection 2detecting featurespainted, taped, or otherwise marked onto the floor3, wall tracking 2detecting distance from thewall3, etc.It can also be used to scan a defined area0 the transmitter emits a beam of light into the scanone, the reflected light is used to detect a change in the reflected light thereby scanning thedesired one.

A,&+a%$ # &$rar" ra&a%$

1. Ra&a%$ %*"r0#0"%"r

$ompared to various other methods of temperature measurement, radiation thermometers havefollowing featuresa3 (easurement without direct contact with the objectb3 >aster responsec3 6asy pattern measurements.'etectors used for radiation thermometers depend upon the temperature and material of theobject to be measured. >or e1ample, glass have peak wavelength near " _m and hence, detectorssensitive to these wavelengths are used.2. M#&%'r" a$a,(>"r

These analyers use those wavelengths which are absorbed by moisture in I/ region, i.e., #.#_m, #.H _m, #. _m, and .M _m. 7bjects are irradiated with light having these wavelengths andalso with reference wavelengths. )ights reflected from the objects depend upon the moisturecontent and is detected by analyer to measure moisture 2ratio of reflected light at thesewavelengths to the reflected light at reference wavelength3. In5aAs %I9 photodiodes, %b+photoconductive detectors are employed in moisture analyers.

/. IR I0a-&$- "6&+"This is one of the prime applications of I/ waves, primarily by virtue of its property that it is notvisible. It is used for thermal imagers, night vision devices, etc.Water, rocks, soil, vegetation, the atmosphere, and human tissue all features emit I/ radiation.Thermal infrared detectors measure these radiations in I/ range and map the spatial temperaturedistributions of the objectVarea on an image. Thermal imagers usually composed of InF+b 2indiumantimonide3, 5dF?g 2mercuryDdoped germanium3, ?gF$dFTe 2mercuryDcadmiumDtelluride3

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The detectors are cooled to low temperatures using li;uid helium or li;uid nitrogen. $ooling thedetectors insures that the radiant energy 2photons3 recorded by the detectors comes from theterrain and not from the ambient temperature of objects within the scanner itself.

?. R"0#%" "$&$-As all objects emit light, the measurement of each wavelength of this emitted light provides lotsof specific information about the object. This is precisely what is done in remote sensing toobtain information like temperature of land and sea water, gas concentration of atmosphere, etc.@. O%&+a, P#!"r 0"%"r

>or long distance optical communication systems, I/ beams in the wavelength region from #.B to#." are employed. 7ptical power meters are used to measure light intensity, optical fibertransmission loss, laser power, etc. in applications like optical fiber communications, lasers, etc.They use In5aAs %I9 photodiodes, etc. for optical power measurement.

. S#r%&$- "6&+"These devices use the inherent property of absorption of some I/ wavelengths to sort agriculturalcrops from stones, clods, etc. +uch devices use In5aAs %I9 photodiodes, %b+ detectors.4. LD M#$&%#r

The output level and emission wavelength of a )aser 'iode varies with the temperature. >or thepurpose of automatic stabiliation of )aser 'iode emission wavelength, )aser diode power ismonitored using In5aAs %I9 photodiodes, InAs, In+b detectors, etc

LIUID CRYSTAL DISPLAY

)$' 2)i;uid $rystal 'isplay3 screen is an electronic display module and find a wide range of

applications. A #L1 )$' display is very basic module and is very commonly used in various devices and

circuits. These modules are preferred over seven segments and other multi segment )6's. The reasons

beingF )$'s are economical0 easily programmable0 have no limitation of displaying special * even

custom characters 2unlike in seven segments3, animations and so on.

A #L1 )$' means it can display #L characters per line and there are such lines. In this )$' each

character is displayed in "1M pi1el matri1. This )$' has two registers, namely, $ommand and 'ata.

The command register stores the command instructions given to the )$'. A command is an instruction

given to )$' to do a predefined task like initialiing it, clearing its screen, setting the cursor position,

controlling display etc. The data register stores the data to be displayed on the )$'. The data is the A+$II

value of the character to be displayed on the )$'.

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P&$ D&a-ra0

P&$ D"+r&%$

P&$N#

F'$+%$ Na0"

# 5round 2!@3 5round

+upply voltage0 "@ 2H.M@ R ".B@3 @cc

B $ontrast adjustment0 through a variable resistor @66H +elects command register when low0 and data register when high /egister +elect

" )ow to write to the register0 ?igh to read from the register /eadVwrite

L +ends data to data pins when a high to low pulse is given 6nable

M Dbit data pins '-!

'-#

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'-

#! '-B

## '-H

# '-"

#B '-L

#H '-M

#" -acklight @$$2"@3 )edC

#L -acklight 5round 2!@3 )edD

R"='&r" T*"#r(

)$' displays are connected through #H pinsF data pins 2'!D'M3, B control pins 2/+, 6, /VW3, and three

power lines 2@dd, @ss, @ee3. +ome )$'s have )6' backlight feature that helps to read the data on the

display during low illumination conditions. +o they have two additional connections 2)6'C and )6'D3,

making altogether #L pin.

C#$%r#, &$

The control pin /+ determines if the data transfer between the )$' module and an e1ternal

microcontroller are actual character data or commandVstatus. When the microcontroller needs to send

commands to )$' or to read the )$' status, it must be pulled low. +imilarly, this must be pulled high if

character data is to be sent to and from the )$' module.

The direction of data transfer is controlled by the /VW pin. If it is pulled )ow, the commands or character

data is written to the )$' module. And, when it is pulled high, the character data or status informationfrom the )$' registers is read. ?ere, we will use one way data transfer, i.e., from microcontroller to )$'

module, so the /VW pin will be grounded permanently.

The enable pin 263 initiates the actual data transfer. When writing to the )$' display, the data is

transferred only on the high to low transition of the 6 pin

P#!"r ',( &$

Although most of the )$' module data sheets recommend C"@ d.c. supply for operation, some )$'s

may work well for a wider range 2B.! to "." @3. The @dd pin should be connected to the positive power

supply and @ss to ground. %in B is @ee, which is used to adjust the contrast of the display. In most of thecases, this pin is connected to a voltage between ! and @ by using a preset potentiometer.

Da%a &$

%ins M to #H are data lines 2'!D'M3. 'ata transfer to and from the display can be achieved either in Dbit

or HDbit mode. The Dbit mode uses all eight data lines to transfer a byte, whereas, in a HDbit mode, a byte

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is transferred as two HDbit nibbles. In the later case, only the upper H data lines 2'HD'M3 are used. This

techni;ue is beneficial as this saves H inputVoutput pins of microcontroller. We will use the HDbit mode.

LCD I$&%&a,&>a%$

-efore you may really use the )$', you must initialiation and configure it. This is

accomplished by sending a number of initialiation instructions to the )$'.

The first instruction we send must tell the )$' whether weEll be communicating with it

with an Dbit or HDbit data bus.

We also select a "1 dot character front.

These two options are selected by sending the command Bh to the )$' as a command.

>or sending command to )$' you have to do the following things.

69 Z !

/+ Z !V#2!Z$ommand, #Zdata3

'ATA Z 111 2Any command in the table, or any character to be displayed3 /W Z !2Write mode selected3

69 Z #

+ome 'elay

69 Z !27bserve the high to low transition on 693

6nable pin should be made to go a transition from high to low while you are writing the

)$'. This is called as negative edge triggering.

-ut when you are reading the content of any pin of the )$' i.e. /VWZ#, you have to

make 6nable pin to go from low to high transition. This is also referred to as positive

edge triggering.

LCD C#00a$ C#"

When /+Z!, we can send several commands to )$' which will be collected by the data bits 2'!D'M3.

There are several commands which can let perform several different function they all are listed as underF

CODE (HEX) COMMAND TO LCD

INSTRUNCTION REGISTER

# $lear 'isplay +creen

/eturn ?ome

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H 'ecrement $ursor 2shift $ursor to )eft3

" +hift 'isplay /ight

L Increment $ursor 2shift cursor to right3

M +hift 'isplay )eft

'isplay 7ff, $ursor 7ff

A 'isplay 7ff, $ursor 7n

$ 'isplay 7n, $ursor 7ff

6 'isplay 7n, $ursor -linking

> 'isplay 7n, $ursor -linking

#! +hift $ursor %osition to )eft

#H +hift $ursor %osition to /ight

# +hift the entire 'isplay to The )eft

#$ +hift the entire 'isplay to The /ight

! >orce $ursor to -eginning to #st line

$! >orce $ursor to -eginning to nd line

B lines and "


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1 RPM 12V DC M#%#r

#!/%( #@ '$ geared motors for robotics applications. @ery easy to use and available in

standard sie. 9ut and threads on shaft to easily connect and internal threaded shaft for easily

connecting it to wheel

'$ (otors are widely used for motion control in manufacturing industries. (otion of '$ motor

is controlled using '$ 'rive. '$ drive changes the speed and direction of a motor. (any of the

'$ drives provides programmable facilities means to program the motion of motor. +o here I am

giving one such e1ample where one can completely program the motion of motor. &sing this

controller one can

$hange the direction of motor

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$hange the speed of motor

$hange the running mode of motor in continuous, reversible or jogging

$hange the forward and reverse running time of motor

>eatures

#!/%( #@ '$ motors with 5earbo1

B!!!/%( base motor

Lmm shaft diameter with internal hole

#"gm weight

+ame sie motor available in various rpm

!."kgcm tor;ue

LM 4@ VOLTAGE REGULATOR

@oltage /egulator is one of the most important and commonly used electrical component.

@oltage /egulators are responsible for maintaining a %"a( 6#,%a-"across an 6lectronic system.

M!" is a voltage regulator integrated circuit. It is a member of M11 series of fi1ed linear voltage

regulator I$s. The voltage source in a circuit may have fluctuations and would not give the fi1ed

voltage output. The voltage regulator I$ maintains the output voltage at a constant value. The 11

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in M11 indicates the fi1ed output voltage it is designed to provide. M!" provides C"@ regulated

power supply. $apacitors of suitable values can be connected at input and output pins depending

upon the respective voltage levels.

P&$ D&a-ra0:

P&$ D"+r&%$F

Pin

No

Function Name

1 Input voltage (5V-18V) Input

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2 Ground (0V) Ground

3 Regulated output; 5V (4.8V-5.2V) Output

H#! %# U" a$ IC34@ 6#,%a-" R"-',a%#r

@oltage regulator I$Es are the I$:s that are used to regulate voltage. IC34@ & a @6 V#,%a-"

r"-',a%#rthat restricts the voltage output to" v. It comes with provision to add heat sink .The

ma1imum value for input to the power ` @oltage regulator is B" v. it can provide a constant steady

voltage flow of " v for higher voltage input till the threshold limit of B"v. If the voltage is near to

M." v then it does not produce any heat and hence no need for heat sin;ue. If the voltage input is

more, then the heat produced is more. The schematic given below shows *#! %# '" a$ IC34@. There are B pins in IC34@, pin # takes the input voltage and pin B produces the output

voltage. The 59' of both input and out are given to pin .+ave this picture for reference.

4@ V#,%a-" R"-',a%#r C&r+'&%

I have attached an image of M!" I$ to describe its pin configuration setting. In addition to that I

have also attached a small fully working voltage regulator circuit diagram with this tutorial. Thetwo capacitors used in the voltage regulator circuit are not mandatory but they are good toma1imie voltage regulation. The capacitor values I have used in this circuit are not written onstone, you can change them slightly. M!" I$ has a thermal shutdown feature to protect the I$ incase of overheating so it should be safe to use M!" without a heat sink plate for less than !!mAload. ?owever should your load cross !!mA, you should consider using a heat sink plate. ?eatsink plate should be large enough to bring M!" heat to such a level that you can comfortablytouch it. M!" is a linear voltage regulator, so it is not very efficient and it has drop out voltage

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problem. It wastes a lot of energy in the form of heat. =ou can calculate the wasted energy withfollowing formula. This formula will also help you to estimate the sie of heat sink plate you willre;uire to disperse amount of heat generated by M!". 2Input @oltage R "3 1 7utput $urrent+uppose the input #" volt and output current you re;uire is ." Amp by using above formula 2#" R

"3 1 !." Z #!!." Z "W"W energy is being wasted as heat and you will need a decent sied heat sink plate to dispersethis heat to ease your M!". 7n the other hand the energy you are actually using is only 2" 1!."Amp3 Z."W. +o you are going to waste twice energy then you are actually utiliing. 7n theother hand, if give your M!" @ as input at the same amount of load, only W 2D"3 1 !." energy will be wasted as heat. +o the conclusion is, the higher the input voltage gets, the lessefficient your M!" will be. =ou should try to stay slightly over M."@. ?owever don:t get bellowM."@ as your M!" won:t give a regulated output if the input voltage get bellow M."@. If yourinput voltage is less than M." like L@ then you should consider using a low dropout voltageregulator such as )(H!. %in connections of )(H! are also same like M!".=ou don:t need e1tra components to create a " volt regulated power supply with M!". ?owever

it is a good idea to use one capacitor on input and one on output pins to make output voltagesmooth but then again, they are not necessary to be used. As per specs, M!" input voltage shouldrange between M."@ to B"@ but personally I haven:t tried more than #"@ yet. (a1imum outputcurrent of M!" is #A with a good sied heat sink plate. If you are planning to use more than oneM!" in parallel to get more current 2above #A3, you better try to put ."7hm 2#!W3 resistor onthe output pin of each transistor to cover the slight voltage difference as technically no two M!"can provide e1actly same output voltage.

L25/D

)B' is a dual H/0*-&% motor driver integrated circuit 2I$3. (otor drivers act as currentamplifiers since they take a lowDcurrent control signal and provide a higherDcurrent signal. Thishigher current signal is used to drive the motors.

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)B' contains two inbuilt ?Dbridge driver circuits. In its common mode of operation, two '$motors can be driven simultaneously, both in forward and reverse direction. The motoroperations of two motors can be controlled by input logic at pins * M and #! * #". Input logic!! or ## will stop the corresponding motor. )ogic !# and #! will rotate it in clockwise and

anticlockwise directions, respectively.

6nable pins # and 2corresponding to the two motors3 must be high for motors to start operating.When an enable input is high, the associated driver gets enabled. As a result, the outputs becomeactive and work in phase with their inputs. +imilarly, when the enable input is low, that driver isdisabled, and their outputs are off and in the highDimpedance state.

F"a%'r"#L25/D

The )B' is an integrated circuit motor driver that can be used for simultaneous, biD

directional control of two small motors.

+mall means small. The )B' is limited to L!!mA, but in reality can only handle much

small currents unless you have done some serious heat sinking to keep the easetemperature down.

&nsure about whether the )B will work with your motor\

?ook up the circuit and run your motor while keeping your finger on the chip. If it gets

too got to touch, you can:t use it with your motor. 29ote to studentsF the )B' should beok for your small motor but is not 7k for your gear motor3.

The )B' comes in a standard #LDpin, dual in line integrated circuit package. There is

an )B' and an )B' part number. %ick the 8'4 version because it has built in flyback diodes to minimie inductive voltage spikes.

The pin out for the )B in the #L pin package is shown below in top view.

P&$ D&a-ra0:

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P&$ D"+r&%$:

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P&$N#

F'$+%$ Na0"

# 6nable pin for (otor #0 active high 6nable #,

Input # for (otor # Input #

B 7utput # for (otor # 7utput #

H 5round 2!@3 5round

" 5round 2!@3 5round

L 7utput for (otor # 7utput

M Input for (otor # Input

+upply voltage for (otors0 D#@ 2up to BL@3 @cc

6nable pin for (otor 0 active high 6nable B,H

#! Input # for (otor # Input B

## 7utput # for (otor # 7utput B

# 5round 2!@3 5round#B 5round 2!@3 5round

#H 7utput for (otor # 7utput H

#" Input for (otor # Input H

#L +upply voltage0 "@ 2up to

LM/2?

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)(BH is a #Hpin I$ consisting of four independent operational amplifiers 2opDamps3compensated in a single package. 7pDamps are high gain electronic voltage amplifier with

differential input and, usually, a singleDended output. The output voltage is many times higherthan the voltage difference between input terminals of an opDamp.

These opDamps are operated by a single power supply )(BH and need for a dual supply iseliminated. They can be used as amplifiers, comparators, oscillators, rectifiers etc. Theconventional opDamp applications can be more easily implemented with )(BH .

P&$ D&a-ra0:

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P&$ D"+r&%$:

PinNo

Function Name

1 Output of 1t!o"parator Output 1

2 Invert#ng #nput of 1t!o"parator Input 1-

3 $on-#nvert#ng #nput of 1t!o"parator Input 1%

4 &uppl' voltage; 5V (up to 32V) V!!

5 $on-#nvert#ng #nput of 2nd!o"parator Input 2%

Invert#ng #nput of 2nd!o"parator Input 2- Output of 2nd!o"parator Output 2

8 Output of 3rd!o"parator Output 3

* Invert#ng #nput of 3rd!o"parator Input 3-

10 $on-#nvert#ng #nput of 3rd!o"parator Input 3%

11 Ground (0V) Ground

12 $on-#nvert#ng #nput of 4t+!o"parator Input 4%

13 Invert#ng #nput of 4t+!o"parator Input 4-

14 Output of 4t+!o"parator Output 4

M&+r#+#$%r#,,"r P5V@1RD2

1. G"$"ra, "+r&%$

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The %@"#/' is an !$"# microcontroller with LH O- >lash and #!H bytes of

data /A(.

A key feature of the %@"#/' is its


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?.&$ &a-ra0 # P5V@1RD2 0&+r#+#$%r#,,"r

S(0#, T(" D"+r&%$

%!.! to %!.M IV7 P#r% : %ort ! is an Dbit open drain biDdirectional IV7 port. %ort! pins that have #:s written to them float, and in this state canbe used as highDimpedance inputs.%ort ! is also the multiple1edlowDorder address anddata bus during accesses to e1ternal code and data memory. Inthis application, it uses strong internal pullDups whentransitioning to #:s. %ort ! also receives the code bytes dur ing

the e1ternal host mode programming, and outputs the code bytesduring the e1ternal host mode verification. 61ternal pullDups arere;uired during program verification or as a generalpurpose IV7port.

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%#.! to %#.M IV7 withinternal pullD

up

P#r% 1: %ort # is an Dbit biDdirectional IV7 port with internalpullDups. The %ort # pins are pulled high by the internal pullDupswhen #:s are written to them and can be used as inputs in thisstate. As inputs, %ort # pins that are e1ternally pulled )7W will

source current 2II)3 because o f the internal pullDups. %#.", %#.L,%#.M have high current drive of #L mA. %ort # also receives thelowDorder address bytes during the e1ternal host modeprogramming and verification.

%#.! IV7T2: 61ternal count input to TimerV$ounter or $lockDoutfrom TimerV$ounter

%#.#

I

T2EF TimerV$ounter captureVreload trigger anddirection control

%#. I

ECIF 61ternal clock input. This signal is the e1ternalclock input for the %$A.

%#.B IV7

CEF $aptureVcompare e1ternal IV7 for %$A (odule !.6ach captureVcompare module connects to a %ort # pinfor e1ternal IV7. When not used by the %$A, this pin canhandle standard IV7.

%#.H

IV7 SSF +lave port select input for +%ICE1F $aptureVcompare e1ternal IV7 for %$A (odule #

%#." IV7 MOSIF (aster 7utput +lave Input for +%ICE2F $aptureVcompare e1ternal IV7 for %$A (odule

%#.L

IV7 MISOF (aster Input +lave 7utput for +%ICE/F $aptureVcompare e1ternal IV7 for %$A (odule B

%#.M

IV7 SCKF (aster 7utput +lave Input for +%ICE?F $aptureVcompare e1ternal IV7 for %$A (odule H

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%.! to%.M

IV7 with

internal pullDup

P#r% 2F %ort is an Dbit biDdirectional IV7 port withinternal pullDups. %ort pins are pulled ?I5? by theinternal pullDups when #:s are written to them and can

be used as inputs in this state. As inputs, %ort pins thatare e1ternally pulled )7W will source current 2II)3because of the internal pullDups. %ort sends thehighDorder address byte during fetches from e1ternalprogram memory and during accesses to e1ternal 'ata(emory that use #LDbit address . In thisapplication, it uses strong internal pullDups whentransitioning to #:s. %ort also receives some control signalsand a partial of highDorder address bits duringthe e1ternal host mode programming and verification.

%B.! to%B.M IV7with internal pullDup

P#r% /F %ort B is an Dbit bidirectional IV7 port withinternal pullDups. %ort B pins are pulled ?I5? by theinternal pullDups when #:s are written to them and canbe used as inputs in this state. As inputs, %ort B pins thatare e1ternally pulled )7W will source current 2II)3because of the internal pullDups. %ort B also receivessome control signals and a partial of highDorder addressbits during the e1ternal host mode programming andverification.

%B.!

I RDF serial input port

%B.# 7 TDF serial output port

%B. I INTF e1ternal interrupt ! input

%B.B I INT1F e1ternal interrupt # input

%B.H I TF e1ternal count input to TimerV$ounter !

%B." I T1F e1ternal count input to TimerV$ounter #

%B.L

7 WRF e1ternal data memory write strobe

%B.M 7 RDF e1ternal data memory read strobe

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%+69:

IV7

Pr#-ra0 S%#r" E$a,"F %+69: is the read strobe fore1ternal program memory. When the device is e1ecutingfrom internal program memory, %+69: is inactive2?I5?3. When the devic

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