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106168730 Lav bv ser Cohgcfcgcmmunication 60

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    *4I6IA4

    This is to certify that or! hich is "eing #resente$ in the #ro%ect

    entitle$ LASER COMMUNICATIONsu"mitte$ "y Mr Akshat MittaMiss (eha Singh' Mr Shrey Agar'a' Mr Mudit *ander' Miss Bharti

    ,oshi stu$ent of final year BTech In ELECTRONICS &

    COMMUNICATION in #artial fulfillment of the re(uirement for aar$ of

    the $egree of BTech in ELECTRONICS & COMMUNICATION is a recor$

    of stu$ents or! carrie$ out "y them un$er my gui$ance an$ su#er)ision

    As #er the can$i$ates $eclaration this or! has not "een su"mitte$

    elsehere for the aar$ of any other $egree

    ated: 2< Ari 2012 Signature of *ro%ect +ui$e

    Pace: Meerut (ame, Miss Sati Singh

    esignation,843**

    Signature of *ro%ect Incharge Signature of -O.

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    A=(5>89M(4

    ?Enthusiasm is the feet of all progresses, with it there is

    accomplishment and without it there are only slits alibis.@

    Ac!nole$gment is not a ritual "ut is certainly an im#ortant thing forthe successful com#letion of the #ro%ect At the time hen e ere ma$e to

    !no a"out the #ro%ect' it as really )ery tough to #rocee$ further as e

    ere to $e)elo# the same on a #latform' hich as ne to us More so' the

    co$ing #art seeme$ so tric!y that it seeme$ to "e im#ossi"le for us to

    com#lete the or! ithin the gi)en $uration

    /e really feel in$e"te$ in ac!nole$ging the organi0ational su##ort

    an$ encouragement recei)e$ from the management of our college.

    The tas! of $e)elo#ing this system oul$ not ha)e "een #ossi"leithout the constant hel# of our mentors /e ta!e this o##ortunity to

    e1#ress our #rofoun$ sense of gratitu$e an$ res#ect to those ho hel#e$ us

    throughout the $uration of this #ro%ect

    /e e1#ress our gratitu$e to Mr. Saurabh Sharma !7.5.;MI4& Miss.

    S'ati Singh!8ecturer;MI4& /e oul$ again li!e to than! all of them for

    gi)ing their )alua"le time to us in $e)elo#ing this #ro%ect

    ated:2< Ari 2012 Mr A!shat Mittal

    Pace: Meerut Miss Neha Singh

    Mr Shrey Agaral

    Mr Mu$it Ran$er

    Miss Bharti 2oshi

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    TABLE OF CONTENTS

    INTRODUCTION

    PLATFORM USED

    AIM OF THE PROJECT

    BLOCK DIAGRAM

    WORKING OF THE PROJECT

    CIRCUIT DIAGRAM

    COMPONENT LIST

    CIRCUIT DESCRIPTION

    PCB LAYOUT

    STEPS FOR MAKING PCB

    PROGRAMMING

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    SENSING UNIT DESCRIPTION

    COMPONENTS DESCRIPTION

    APPLICATION

    CONCLUSION

    REFERENCE

    Intro$uction

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    I(4*534I5(,

    Laser communications systems are ireless connections through the

    atmos#here They or! similarly to fi"er o#tic lin!s' e1ce#t the "eam is

    transmitte$ through free s#ace /hile the transmitter an$ recei)er must

    re(uire line3of3sight con$itions' they ha)e the "enefit of eliminating the nee$

    for "roa$cast rights an$ "urie$ ca"les Laser communications systems can "e

    easily $e#loye$ since they are ine1#ensi)e' small' lo #oer an$ $o not

    re(uire any ra$io interference stu$ies The carrier use$ for the transmission

    signal is ty#ically generate$ "y a laser $io$e To #arallel "eams are

    nee$e$' one for transmission an$ one for rece#tion .ue to "u$get

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    restrictions' the system im#lemente$ in this #ro%ect is only one ay

    This #ro%ect is microcontroller "ase$ Laser communication system

    use$ for the successful transmission of $ata In this #ro%ect using to

    microcontroller 'e are transmitting $ata from one en$ using laser

    transmitter an$ at other en$ recei)e$ "y laser recei)er hich is connecte$ to

    the #in of microcontroller 'here the transmitte$ as ell as recei)e$ $ata

    $is#laye$ on lc$

    Platform used

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    7ard'are reuirements,

    1& Microcontroller AT45C67

    2& L.R

    $& LM8496 Regulator

    +& *oer Su##ly

    )& Resistors

    %& Ca#acitors

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    The Aim of this #ro%ect is to $esign a communication system through

    Laser'a laser $io$e at the transmitting en$ act as a trans$user to con)ert the

    $igital $ata into laser form an$ transmitte$ 'at the recei)ing en$ a laser

    transistor con)ert the laser $ata into $igital form

    -ere the moti)e of using Laser is that /hile the transmitter an$

    recei)er must re(uire line3of3sight con$itions' they ha)e the "enefit of

    eliminating the nee$ for "roa$cast rights an$ "urie$ ca"les Laser

    communications systems can "e easily $e#loye$ since they are ine1#ensi)e'

    small' lo #oer an$ $o not re(uire any ra$io interference stu$ies

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    Block diagram

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    Laser communication

    TRANSMITTER

    TRANSMITTER

    LASER DIODE

    SUPPLYSECTION

    MICROCONTROLLER

    Commun!"#on

    DISPLAY SECTIONUSING

    LCD

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    Receiver

    MICRO CONTROLLER 89C51

    RECEI$ER

    LDR

    DISPLAY SECTIONUSING

    LCDSUPPLY

    SECTION

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    WORKING OFTHE PROJECT

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    There are to microcontroller one at sen$ing en$ an$ the other at

    recei)ing en$ Laser transmitter is connecte$ to the #in of the

    microcontroller at the sen$ing en$ an$ the LASER recei)er is

    connecte$ to microcontroller at recei)er en$hene)er a #erson is

    ishing to sen$ the $ata the microcontroller ma!e the laser transmitter

    to sen$ the fre(uency corres#on$ing to that $ata an$ at recei)er en$

    that fre(uency can change to the original $ata form hich ill $is#lay

    on the lc$ connecte$ to the #in of the microcontrollerin this ay the

    function of transmitting the $ata through laser recei)er an$

    transmitter ha)e "een com#lete$

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    CIRCUIT

    DIAGRAM

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    Attach the hard

    copy of the cktda!ra"

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    Component list

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    Attach hard copy of

    Component list

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    CIRCUITDE#CRIPTION

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    POWER SPPL! SECTION"

    Co$%%t% of&1% RLMT Connector&&& I# ' " !onn(!#o) u'(* #o !onn(!#

    #+( '#(, *o-n #)"n'.o)m() #o #+( /)*0( )(!#.()%

    % Bri#$e Recti%ier &&& I# ' " .u22 -"3( )(!#.() u'(* #o!on3()# "! n#o *! 4 9&153 "! m"*( / #)"n'.o)m() '!on3()#(* n#o *! -#+ #+( +(2, o. )(!#.()%

    6% Ca&acitor" &&&&&I# ' "n (2(!#)o2#! !","!#o) o.)"#n0 1777M65$ u'(* #o )(mo3( #+( ),,2('% C","!#o)' #+( !om,on(n# u'(* #o ,"'' #+( "! "n* /2o! #+( *!%

    :% Re$u'ator" &&&&LM;875 ' u'(* #o 03( " .u(n! '+0+?',('@%

    So #+( ou#,u# o. 'u,,2 '(!#on ' 53 )(0u2"#(* *!%

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    MICROCONTROLLER SECTION"

    R(>u)(' #+)(( !onn(!#on' #o /( 'u!!(''.u22 *on( .o)#' o,()"#on #o /(0n%

    1% (v su&&'*" T+' 53 'u,,2 ' )(>u)(* .o) #+(!on#)o22() #o 0(# '#")# -+!+ ' ,)o3*(* .)om #+( ,o-()'u,,2 '(!#on% T+' 'u,,2 ' ,)o3*(* "# ,n no%61"n*:7 o. #+( 89!51 !on#)o22()%

    % Cr*sta' Osci''ator" A !)'#"2 o'!22"#o) o. 1 MH '!onn(!#(* "# ,n no%194u(n! .o) #+( !on#)o22()% T+( !)'#"2 o'!22"#o)-o)' on ,(o(2(!#)! (..(!#%T+( !2o! 0(n()"#(* 'u'(* #o *(#()mn( #+( ,)o!(''n0 ',((* o. #+(!on#)o22()% T-o !","!#o)' ")( "2'o !onn(!#(* on( (n*-#+ #+( o'!22"#o) -+2( #+( o#+() (n* ' !onn(!#(* -#+#+( 0)oun*% A' # ' )(!omm(n*(* n #+( /oo #o!onn(!# #-o !()"m! !","!#o) o. 7 ,.:7,. #o'#"/2( #+( !2o! 0(n()"#(*%

    6% Reset section" I# !on''#' o. "n )! n(#-o)!on''#n0 o. 17M65$ !","!#o) "n* on( )(''#"n!( o.1% T+' '(!#on ' u'(* #o )('(# #+( !on#)o22()!onn(!#(* "# ,n no%9 o. AT89!51%

    +ISPLA! SECTION"

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    LC+,LI-I+ CR!STAL +ISPLA!)

    MICROCONTROLLER BASED LCD DISPLAY 4#+' ,)o(!# ' "n (m/(**(*,)o(!# % Em/(**(* ' #+( !om/n"#on o. 'o.#-")( "n* +")*-")( /(.o)(*('0nn0 "n (m/(**(* ,)o(!# # ' #+( .)'# '#(, #o *('0n #+( ,)o,()+")*-")( .o) #+( *(')(* ",,2!"#on% H()( -( ")( n#()."!n0 #+( LCD4

    LIUID CRYSTAL DISPLAY -#+ #+( M!)o!on#)o22()4 -( ")( u'n0 ATMEL'()(' 51 !on#)o22() 89!51 !on#)o22()% I# ' " :7 ,n IC4 #+( .)'# '#(, -+2(*('0nn0 +")*-")( ' #o *('0n #+( )(>u)(* ,o-() 'u,,2 "' #+(!on#)o22() o,()"#(' on 5 3 'u,,2 'o .)'# -( +"3( #o *('0n #+()(0u2"#(* 'u,,2 -#+ #+( +(2, o. #)"n'.o)m()4 )(0u2"#o) "n* .2#()n0!","!#o)%N(

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    )(2" !"n *"m"0( #+( ,)o!(''o) -+(n #+( #)"n''#o) BC5:;' on% A ,u22 *o-n )(''#o) o. 3"2u( ' "2'o u'(*%

    PC' (A)OUT

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    Attach the hardcopy of the

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    co"po$e$t

    *ayo+t

    Attach the hardcopy of the pc,

    *ayo+t

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    #TEP# FORMAKING PC'

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    P)(,")( #+( 2"ou# o. #+( !)!u# ?,o'#3(@%

    Cu# #+( ,+o#o.2m ?'20+#2 /00()@ o. #+( '( o. #+( 2"ou#%

    P2"!( #+( 2"ou# n #+( ,+o#o,)n#() m"!+n( -#+ #+(,+o#o.2m "/o3( #% M"( 'u)( #+"# #+( /)om*( ?*")@ '*( o.#+( .2m ' n !on#"!# -#+ #+( 2"ou#%

    S-#!+ on #+( m"!+n( / ,)(''n0 #+( ,u'+ /u##on .o) 5 '(!%

    D, #+( .2m n #+( 'o2u#on ,)(,")(* ?*(3(2o,()@ / mu"n##(' n -"#()%

    No- !2("n #+( .2m / ,2"!n0 # n #+( #)" !on#"nn0 -"#() .o)

    1 mn%

    A.#() #+'4 *, #+( .2m n #+( .u* ,+o#o)(''#4 -#+ #+( +(2, o. *,!o"# m"!+n(%

    No- !2, #+( PCB n(

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    No- ,2"!( #+( n(0"#3( on #+( #o, o. #+( PCB n #+( U$m"!+n(4 '(# #+( #m() .o) "/ou# %5 mnu#( "n* '-#!+ on #+(U$ 20+# "# #+( #o,%

    T"( #+( LPR *(3(2o,() n " !on#"n() "n* )0o)ou'2 mo3( #+(PCB n #%

    A.#() #+'4 -"'+ # -#+ -"#() 3() 0(n#2%

    T+(n ",,2 LPR *( on # -#+ #+( +(2, o. " *)o,,() 'o #+"# # '!om,2(#(2 !o3()(* / #%

    No- !2"m, #+( PCB n #+( (#!+n0 m"!+n( #+"# !on#"n' .())!!+2o)*( 'o2u#on .o) "/ou# 17 mnu#('%

    A.#() (#!+n04 -"'+ #+( PCB -#+ -"#()4 -,( # " *) !2o#+'o.#2%

    Fn"22 )u/ #+( PCB -#+ " '#((2 -oo24 "n* #+( PCB ' )("*%

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    Pro!ra""$!

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    Attach hardcopy of

    pro!ra""$!

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    #EN#ING UNITDE#CRIPTION

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    Laser transmitter

    Laser receiver

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    A aser diodeis a laserhere the acti)e me$ium is a semicon$uctorsimilar

    to that foun$ in a light3emitting $io$e The most common an$ #ractical ty#e

    of laser $io$e is forme$ from a#3n %unctionan$ #oere$ "y in%ecte$ electric

    current These $e)ices are sometimes referre$ to as injection laser diodesto

    $istinguish them from

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    emission is necessary to initiate laser oscillation' "ut it is one among se)eral

    sources of inefficiency once the laser is oscillating

    The $ifference "eteen the #hoton3emitting semicon$uctor laser an$

    con)entional #honon3emitting

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    stimulate$ emission causes gain in an o#tical a)e

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    enough' a$$itional side modesmay also lase Some laser $io$es' such as

    most )isi"le lasers' o#erate at a single a)elength' "ut that a)elength is

    unsta"le an$ changes $ue to fluctuations in current or tem#erature

    .ue to $iffraction' the "eam $i)erges

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    MI*55(4*588* A4"#)1

    6eatures

    F Com#ati"le ith MCS367G *ro$ucts

    F 4H Bytes of In3System Re #rogramma"le lash Memory

    F En$urance, 7'999 /riteErase Cycles

    F ully Static O#eration, 9 -0 to JK M-0

    F Three3le)el *rogram Memory Loc!

    F J6@ 1 43"it Internal RAM

    F J *rogramma"le IO Lines

    FThree 7@3"it TimerCounters

    F Eight Interru#t Sources

    F *rogramma"le Serial ChannelF Lo3#oer I$le an$ *oer3$on Mo$es

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    .ESCRI*TION

    The AT45C6J is a lo3#oer' high3#erformance CMOS 43"it microcom#uter 4H"ytes of

    lash #rogramma"le an$ erasa"le rea$ only memory

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    Pin escrition

    G

    Su##ly )oltage

    9(

    +roun$

    Port 0

    Port 0 is an "-bit oen drain bi-directiona IC5 ort. As an outut ort; each in cansink eight 448 inuts. >hen 1s are 'ritten to ort 0 ins; the ins can be used as

    high imedance inuts.

    *ort 9 can also "e configure$ to "e the multi#le1e$ lo or$er a$$ress$ata

    "us $uring accesses to e1ternal #rogram an$ $ata memory In this mo$e' *9

    has internal #ull3u#s

    *ort 9 also recei)es the co$e "ytes $uring lash #rogramming an$ out#uts

    the co$e "ytes $uring #rogram )erification E1ternal #ull3u#s are re(uire$

    $uring #rogram )erification

    Port 1

    *ort 7 is an 43"it "i3$irectional IO #ort ith internal #ull3u#s The *ort 7

    out#ut "uffers can sin!source four TTL in#uts /hen 7s are ritten to *ort

    7 #ins' they are #ulle$ high "y the internal #ull3u#s an$ can "e use$ as

    in#uts As in#uts' *ort 7 #ins that are e1ternally "eing #ulle$ lo ill source

    current

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    *S4

    *eset inut. A high on this in /or t'o machine cyces 'hie the osciator is running

    resets the deice.

    A8CP*59

    A$$ress Latch Ena"le is an out#ut #ulse for latching the lo "yte of the a$$ress $uring

    accesses to e1ternal memory This #in is also the #rogram #ulse in#ut

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    Note' hoe)er' that if loc! "it 7 is #rogramme$' EA ill "e internally

    latche$ on reset

    EA shoul$ "e stra##e$ to CC for internal #rogram e1ecutions This #in

    also recei)es the 7J3)olt #rogramming ena"le )oltage

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    Secia 6unction *egisters

    A ma# of the on3chi# memory area calle$ the S#ecial unction Register

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    4imer 0 and 1

    Timer 9 an$ Timer 7 in the AT45C6J o#erate the same ay as Timer 9 an$ Timer 7 in the

    T45C67

    4imer 2

    Timer J is a 7@3"it TimerCounter that can o#erate as either a timer or an

    e)ent counter The ty#e of o#eration is selecte$ "y "it CTJ in the SR

    TJCON

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    oscillator #erio$s' the count rate is 77J of the oscillator in#ut #in' TJ In this

    function' the e1ternal in#ut is sam#le$ $uring S6*J of e)ery machine cycle

    /hen the sam#les sho a high in one cycle an$ a lo in the ne1t cycle' the

    count is incremente$ The ne count )alue a##ears in the register $uring

    S*7 of the cycle folloing the one in hich

    the transition as $etecte$ Since to machine cycles

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    Auto-reoad !3 or o'n ounter&

    Timer J can "e #rogramme$ to count u# or $on hen configure$ in its 7@3"it auto3reloa$

    mo$e This feature is in)o!e$ "y the.CEN

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    Baud *ate 9enerator

    Timer J is selecte$ as the "au$ rate generator "y setting TCLH an$or RCLH

    in TJCON

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    Programmabe ock 5ut

    A 69 $uty cycle cloc! can "e #rogramme$ to come out on *79' as shon

    in igure 6 This #in' "esi$es "eing a regular IO #in' has to alternate

    functions It can "e #rogramme$ to in#ut the e1ternal cloc! for

    TimerCounter J or to out#ut a 69 $uty cycle cloc! ranging from @7 -0 to

    K M-0 at a 7@ M-0 o#erating fre(uency To configure the TimerCounter J

    as a cloc! generator' "it CTJ

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    3A*4

    The UART in the AT45C6J o#erates the same ay as the UART in the AT45C67

    Interruts

    The AT45C6J has a total of si1 interru#t )ectors, to e1ternal interru#ts

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    5sciator haracteristics

    H4A81 and H4A82 are the inut and outut; resectiey; o/ an inerting ami/ier

    that can be con/igured /or use as an on-chi osciator; as sho'n in 6igure

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    har$are inhi"its access to internal RAM in this e)ent' "ut access to the #ort

    #ins is not inhi"ite$ To eliminate the #ossi"ility of an une1#ecte$ rite to a

    #ort #in hen i$le mo$e is terminate$ "y a reset' the instruction folloing

    the one that in)o!es i$le mo$e shoul$ not rite to a #ort #in or to e1ternal

    memory

    Po'er-do'n Mode

    In the #oer3$on mo$e' the oscillator is sto##e$' an$ the instruction that

    in)o!es #oer3$on is the last instruction e1ecute$ The on3chi# RAM an$

    S#ecial unction Registers retain their )alues until the #oer3$on mo$e is

    terminate$ The only e1it from #oer3$on is a har$are reset Reset

    re$efines the SR s "ut $oes not change the on3chi# RAM The reset shoul$

    not "e culti)ate$ "efore CC is restore$ to its normal o#erating le)el an$

    must "e hel$ acti)e long enough to allo the oscillator to restart an$

    sta"ili0e


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