PROJECT REPORT ON
VISITOR COUNTER & AUTOMATIC LOAD CONTROLLER
Submitted in partial fulfillment of the requirements For the award of the degree BC!E"OR OF EN#$NEER$N# $N %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%% EN#$NEER$N#
S&B'$TTE( B) --------------------------------------- (--------------) (--------------) -------------------------------- --------- (---------------) (---------- -----) --------------------- (---------------)
(EPRT'ENT OF %%%%%%%%%%%%%%%%%%%%%%% EN#$NEER$N# %%%%%%%%%%CO""E#E %%%%%%%%%%CO""E#E OF EN#$NEER$N# FF$"$TE( TO %%%%%%%%%%% &N$*ERS$T)
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CERTIFICATE
This is to +ertif, that the dissertation wor- entitled VISITOR COUNTER & AUTOMATIC AUTOMATIC LOAD CONTROLLER is the wor- done b, %%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%submitted %%%%submitted in partial partial fulfillment for the award of .BC!E"OR OF EN#$NEER$N# /B0E12in %%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%Engineering Engineering from%%%%%%%%%%%%%% from%%%%%%%%%%%%%% College of of Engineering affiliated to %%%%%%%%% &ni3ersit, 4 !,derabad 0
________________ ________________ (Head of the department ECE!
____________ (A""#"tant $rofe""or!
E%TERNAL E%AMINER
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CERTIFICATE
This is to +ertif, that the dissertation wor- entitled VISITOR COUNTER & AUTOMATIC AUTOMATIC LOAD CONTROLLER is the wor- done b, %%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%submitted %%%%submitted in partial partial fulfillment for the award of .BC!E"OR OF EN#$NEER$N# /B0E12in %%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%Engineering Engineering from%%%%%%%%%%%%%% from%%%%%%%%%%%%%% College of of Engineering affiliated to %%%%%%%%% &ni3ersit, 4 !,derabad 0
________________ ________________ (Head of the department ECE!
____________ (A""#"tant $rofe""or!
E%TERNAL E%AMINER
2
ACNO'LEDEMENT
The satisfa+tion and euphoria that a++ompan, the su++essful +ompletion of an, tas- would be in+omplete without the mentioning of the people whose +onstant guidan+e and en+ouragement made it possible0 5e ta-e pleasure in presenting before ,ou4 our pro6e+t4 whi+h is result of studied blend of both resear+h and -nowledge0
5e e7pre e7press ss our our earn earnes estt grati gratitu tude de to our our inte interna rnall guid guide4 e4 ssi ssist stan antt Prof Profes esso sor r %%%%%%%%%%%%%%4 %%%%%%%%%%%%%%4 (epartment of ECE4 our pro6e+t guide4 for his +onstant support4 en+ouragement and guidan+e0 5e are grateful for his +ooperation and his 3aluable suggestions0
Finall,4 we e7press our gratitude to all other members who are in3ol3ed either dire+tl, or indire+tl, for the +ompletion of this pro6e+t0
3
DECLARATION
5e4 the undersigned4 de+lare that the pro6e+t entitled )VISITOR COUNTER & AUTOMATIC AUTOMATIC LOAD CONTROLLER *4 being submitted in partial fulfillment for the award of Ba+helor of Engineering (egree in Ele+troni+s and Communi+ation Engineering4 affiliated to %%%%%%%%% &ni3ersit,4 &ni3ersit,4 is the wor- +arried out b, us0
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VISITOR COUNTER AND ROOM LIGHT CONTROLLER
INDEX Contents
Page No.
Abstract…………………………………..... Intro!c"on Intro!c"on to E#bee s$ste#s…… s$ste#s…… M%crocontro&&er M%crocontro&&er AT'(S)*....................... T'(S)*.......................
Har+are Descr%,"on………………… Descr%,"on…………………..
Co%ng…………………………………......
So-+are Descr%,"on………………… Descr%,"on…………………… …
Conc&!s%on……………………………….
Reerences……………………………….
5
VISITOR COUNTER AND ROOM LIGHT CONTROLLER
A+STRACT This Pro6e+t 8utomati+ Room "ight Controller with *isitor Counter using 'i+ro+ontroller9 is a reliable +ir+uit that ta-es o3er the tas- of +ontrolling the room lights as well us +ounting number of persons: 3isitors in the room 3er, a++uratel,0 5hen somebod, enters into the room then the +ounter is in+remented b, one and the light in the room will be swit+hed ON and when an, one lea3es the room then the +ounter is de+remented b, one0 The light will be onl, swit+hed OFF until all the persons in the room go out0 The total number of persons inside the room is also displa,ed on the ;<=> "C(0 The mi+ro+ontroller does the abo3e 6ob0 $t re+ei3es the signals from the sensors4 and this signal is operated under the +ontrol of software whi+h is stored in RO'0 'i+ro+ontroller T?@SA> +ontinuousl, monitor the $nfrared Re+ei3ers4 5hen an, ob6e+t pass through the $R Re+ei3ers then the $R Ra,s falling on the re+ei3ers are obstru+ted this obstru+tion is sensed b, the 'i+ro+ontroller0
6
SOFT'ARE
;1 eil Compiler0 >1 E'BE((E( C CO(E D1 u+Flash
HARD'ARE TOOLS,
;1 'i+ro+ontroller ?@SA> >1 Regulated Power Suppl, A*0 D1 ?@SA> 'i+ro+ontroller 1 BT;D< Tria+ A1 'OCD>; OptoGCoupler $C <1 $R "E( N( P!OTO($O(E P$R H1 ;<=> "C( ($SP")
7
+-o./ D#a0ram,
012* LCD D%s,&a$
M%cro/ IR Sensors
contro&&er AT'(S)*
MOC34*0
5T031 TRIAC DRIVER
OPTO/COUPLER
8
AC LAMPS
E'BE((E( S)SE'S
Embedded s,stems ha3e grown tremendousl, in re+ent ,ears4 not onl, in their popularit, but also in their +omple7it,0 #adgets are in+reasingl, be+oming intelligent and autonomous0 Refrigerators4 airG+onditioners4 automobiles4 mobile phones et+ are some of the +ommon e7amples of de3i+es with built in intelligen+e0 These de3i+es fun+tion based on operating and en3ironmental parameters0 The intelligen+e of smart de3i+es resides in embedded s,stems0 n embedded s,stem4 in general4 in +oGoperates hardware4 operating s,stems4 lowGle3el software binding the operating s,stem and peripheral de3i+es4 and +ommuni+ation software to enable the de3i+e to perform the preGdefined fun+tions0 n embedded s,stem performs a single4 wellGdefined tas-4 is tightl, +onstrained4 is rea+ti3e and +omputes results in real time0 "et us ta-e a detailed loo- at these features of embedded s,stemsI
Single fun+tionedI n embedded s,stem e7e+utes a spe+ifi+ program repeatedl,0
For e7ample4 a pager is alwa,s a pager0 $n +ontrast a des-top s,stem e7e+utes a 3ariet, of programs li-e spreadsheets4 word pro+essors4 et+0 !owe3er there are e7+eptions where in an embedded s,stem2s program is updated with newer program 3ersions0 Cell phones are e7amples of being updated in su+h a manner0
Tightl, +onstrainedI ll +omputing s,stems ha3e +onstraints on design metri+s but
those on embedded s,stems +an be espe+iall, tight0 design metri+ is a measure of an implementation2s features4 su+h as +ost4 sie performan+e and power0
Rea+ti3e and real timeI 'an, embedded s,stems must +ontinuall, rea+t to +hanges
in the s,stem2s en3ironment and must +ompute +ertain results in real time without dela,0
9
Em1edded Hard2are ll embedded s,stems need a mi+ropro+essor4 and the -inds of mi+ropro+essors used in them are quite 3aried0 list of some of the +ommon mi+ropro+essor families is the K$"O# K? famil,4 $ntel ?A:?;??:7 ?< families4 'otorola
Em1edded Soft2are The software for the embedded s,stems is +alled firmware0 The firmware will be written in assembl, languages for time or resour+e +riti+al operations or using higherGle3el languages li-e C or embedded C0 The software will be simulated using mi+ro +ode simulators for the target pro+essor0 Sin+e the, are supposed to perform onl, spe+ifi+ tas-s these programs are stored in Read Onl, 'emories /RO'2s10
App-#.at#on area" for em1edded "3"tem" Embedded software is present in almost e3er, ele+troni+ de3i+e ,ou use toda,0 There is embedded software inside ,our wat+h4 +ellular phone4 automobile4 thermostats4 $ndustrial +ontrol equipment and s+ientifi+ and medi+al equipment0 (efen+e ser3i+es use embedded software to guide missiles and dete+t air+raft2s0 Communi+ation satellites4 medi+al instruments and deep spa+e probes would ha3e been nearl, impossible without these s,stems0 Embedded s,stems +o3er su+h as broad range of produ+ts that generaliation is diffi+ult0 !ere are some broad +ategories0
erospa+e and (efense Ele+troni+s /(E1
Consumer:$nternet appli+ations
(ata Communi+ations
(igital imaging
'edi+al ele+troni+ 'obile data infrastru+tures
10
+-o./ d#a0ram of Em1edded S3"tem,
Embedded
System
Sofw!e
"!dw!e
ALP C #$
P!o%esso! Pe!*e!+s memo!y
Et%&'
F#04re 565, Em1edded S3"tem +-o./ D#a0ram
Software deals with the languages li-e "P4 C4 and *B et+04 and !ardware deals with Pro+essors4 Peripherals4 and 'emor,0 Memor3I
$t is used to store data or address0
$er#phera-" I
These are the e7ternal de3i+es +onne+ted
$ro.e""or I
$t is an $C whi+h is used to perform some tas-
Pro+essors are +lassified into four t,pes li-eI ;0 'i+ro Pro+essor /Lp1 >0 'i+ro +ontroller /L+1 D0 (igital Signal Pro+essor /(SP1 0 ppli+ation Spe+ifi+ $ntegrated Cir+uits /S$C1
11
MICROCONTROLLER Basi+all,4 a mi+ro+ontroller is a de3i+e whi+h integrates a number of the +omponents of a mi+ropro+essor s,stem onto a single mi+ro+hip0 So a mi+ro+ontroller +ombines onto the same mi+ro+hip0 The following +omponentsI
CP& Core
'emor, /Both R' and RO'1
Some Parallel (igital $:Os The mi+ropro+essor is the integration of a number of useful fun+tions into a single $C
pa+-age0 !as the abilit, to e7e+ute a stored set of instru+tions to +arr, out user defined tas-sM also has abilit, to a++ess e7ternal memor, +hips to both read and write data from and to the memor,0 Essentiall,4 a mi+ro+ontroller is obtained b, integrating the -e, +omponents of mi+ropro+essor4 R'4 RO'4 and (igital $:O onto the same +hip die0 'odern mi+ro+ontrollers also +ontain a wealth of other modules su+h as Serial $:O4 Timers4 and nalogue to (igital Con3erters0 There are a large number of spe+ialied de3i+es with additional modules for spe+ifi+ needs0 E0g0 CN +ontrollers0
12
MICROCONTOLLER 6AT78S9:! FEATURES
Compatible with 'CSGA;Produ+ts ? B,tes of $nGS,stem Programmable /$SP1 Flash 'emor, 0* to A0A* Operating Range Full, Stati+ OperationI ! to DD '! >A Programmable $:O "ines D ;
DESCRI$TION OF MICROCONTROLLER AT 78S9:, 13
The T?@SA> is a lowGpower4 highGperforman+e C'OS ?Gbit mi+ro +ontroller with ?b,tes of inGs,stem programmable Flash memor,0 The de3i+e is manufa+tured &sing tmel2s highGdensit, nonG3olatile memor, te+hnolog, and is +ompatible with the industr,Gstandard ?CA; mi+ro +ontroller0 The onG+hip Flash allows the program memor, to be reprogrammed inGs,stem or b, a +on3entional nonG3olatile memor, programmer0 B, +ombining a 3ersatile ?Gbit CP& with inGs,stem programmable flash one monolithi+ +hipM the tmel T?@SA> is a powerful mi+ro +ontroller4 whi+h pro3ides a highl, fle7ible and +ostG effe+ti3e solution to man, embedded +ontrol appli+ations0
14
The T?@SA> pro3ides the following standard featuresI ? b,tes of Flash4 >A< b,tes of R'4 D> $:O lines4 5at+hdog timer4 two data pointers4 three ; is designed with stati+ logi+ for perationdown to ero frequen+, and supports two software sele+table power sa3ing modes0 The $dle 'ode stops the CP& while allowing the R' timer:+ounters4 serial port4 and interrupt s,stem to +ontinue fun+tioning0 The PowerGdown mode sa3es the R' +ontents but freees the os+illator4 disabling all other +hip fun+tions until the ne7t interrupt or hardware reset0 $IN DESCRI$TION OF MICROCONTROLLER AT78S9: 15
VCC
Suppl, 3oltage0 ND
#round0 $ort ;
Port is an ?Gbit open drain biGdire+tional $:O port0 s an output port4 ea+h pin +an sin- eight TT" inputs0 5hen ;sare written to port pins4 the pins +an be used as high impedan+e inputs0 Port +an also be +onfigured to be the multiple7ed low order address:data bus during a++esses to e7ternal program and data memor,0 $n this mode4 P has internal pullGups0 Port also re+ei3es the +ode b,tes during Flash programming and outputs the +ode b,tes during program 3erifi+ation0 E7ternal pullGups are required during program 3erifi+ation0 $ort 5
Port ; is an ?Gbit biGdire+tional $:O port with internal pullGups0 The Port ; Output buffers +an sin-:sour+e four TT" inputs0 5hen ;s are written to Port ; pins4 the, are pulled high b, the internal pullGups and +an be used as inputs0 $n addition4 P;0 and P;0; +an be +onfigured to be the timer:+ounter > e7ternal +ount input /P;0:T>1 and the timer:+ounter > trigger input P;0;:T>E14 respe+ti3el,4 as shown in the following table0 Port ; also re+ei3es the lowGorder address b,tes during Flash programming 0
16
$ort :
Port > is an ?Gbit biGdire+tional $:O port with internal pullGups0 The Port > output buffers +an sin-:sour+e four TT" inputs0 5hen ;s are written to Port > pins4 the, are pulled high b, the internal pullGups and +an be used as inputs0 Port > emits the highGorder address b,te during fet+hes from e7ternal program memor, and during a++esses to e7ternal data memor, that uses ; uses strong internal pullGups when emitting ;s0 (uring a++esses to e7ternal data memor, that use ?Gbit addresses /'O* R$14 Port >emits the +ontents of the P> Spe+ial Fun+tion Register0 Port > also re+ei3es the highGorder address bits and some +ontrol signals during Flash programming and 3erifi+ation0 $ort <
Port D is an ?Gbit biGdire+tional $:O port with internal pullGups0 The Port D output buffers +an sin-:sour+e four TT" inputs0 5hen ;s are written to Port D pins4 the, are pulled high b, the internal pullGups and +an be used as inputs0 s inputs4 Port D pins that are e7ternall, being pulled low will sour+e +urrent /$$"1 be+ause of the pullGups0 Port D also ser3es the fun+tions of 3arious spe+ial features of the T?@SA>4 as shown in the following table0 Port D also re+ei3es some +ontrol signals for Flash programming and 3erifi+ation0
17
RST
Reset input0 high on this pin for two ma+hine +,+les while the os+illator is running resets the de3i+e0 ALE=$RO
ddress "at+h Enable /"E1 is an output pulse for lat+hing the low b,te of the address during a++esses to e7ternal memor,0 This pin is also the program pulse input /PRO#1 during Flash programming0 $n normal operation4 "E is emitted at a +onstant rate of;:< the os+illator frequen+, and ma, be used for e7ternal timing or +lo+-ing purposes0 Note4 howe3er4 that one "E pulse is s-ipped during ea+h a++ess to e7ternal data 'emor,0 $f desired4 "E operation +an be disabled b, setting bit of SFR lo+ation ?E!0 with the bit set4 "E is a+ti3e onl, during a 'O* or 'O*C instru+tion0 Otherwise4 the pin is wea-l, pulled high0 Setting the "EGdisable bit has no effe+t if the mi+ro +ontroller is in e7ternal e7e+ution mode0 $SEN
Program Store Enable /PSEN1 is the read strobe to e7ternal program memor,0 5hen the T?@SA> is e7e+uting +ode from e7ternal program memor,4 PSEN is a+ti3ated twi+e ea+h ma+hine +,+le4 e7+ept that two PSEN a+ti3ations are s-ipped during ea+h a++ess to e7ternal data memor,0 EA=V$$
E7ternal ++ess Enable0 E must be strapped to #N( in order to enable the de3i+e to fet+h +ode from e7ternal program memor, lo+ations starting at ! up to FFFF!0 Note4 howe3er4 that if lo+- bit ; is programmed4 E will be internall, lat+hed on reset0 should be strapped to *CC for internal program e7e+utions0 This pin also re+ei3es the ;>G 3oltProgramming enables 3oltage /*PP1 during Flash programming0
18
%TAL5
$nput to the in3erting os+illator amplifier and input to the internal +lo+- operating +ir+uit0 %TAL:
Output from the in3erting os+illator amplifier0 O".#--ator Chara.ter#"t#."
T"; and T"> are the input and output4 respe+ti3el,4 of an in3erting amplifier that +an be +onfigured for use as an onG+hip os+illator4 as shown in Figure ;0 Either a quart +r,stal or +erami+ resonator ma, be used0 To dri3e the de3i+e from an E7ternal +lo+- sour+e4 T"> should be left un+onne+ted while T"; is dri3en4 as shown in Figure >0
C#r.4#t De".r#pt#on, 19
The +ir+uit shows the mi+ro+ontroller based bidire+tional 3isitor +ounter4 wherein the transmitter and the re+ei3er form the $R dete+tion +ir+uit0 Control logi+ is built around transistors4 operational amplifier "'D@D /$C1 The $R transmitterGre+ei3er setup at the entran+eG+umGe7it of the passage is shown at the blo+- diagram0 Two similar se+tions dete+t interruption of the $R beam and generate +lo+- pulse for the mi+ro+ontroller0
The mi+ro+ontroller +ontrols
+ounting and displa,s the number of persons present inside the hall0 5hen nobod, is passing through the entr,:e7it point4 the $R beam +ontinuousl, falls on phototransistor T;0 5hen infrared beam is interrupted4 +omparator output be+omes low whi+h is gi3en to mi+ro+ontroller0 $f someone interrupts the first the $R beam4 +ounter in+reases and similarl, when se+ond infrared beam is interrupted +ounter de+reases0 The T?@CA> us an ?Gbit mi+ro+ontroller with ? -b of flash based program memor,4 >A< b,tes of R'4 D> input:output lines4 three ;< bits timers:+ounters4 onG +hip os+illator and +lo+- +ir+uitr,0 ;>'! +r,stal is used fro pro3iding +lo+-0 Four (igit HGSegment (ispla, is interfa+ed with the mi+ro+ontroller
20
Hard2are De".r#pt#on $o2er "4pp-3 de".r#pt#on, s the mi+ro+ontroller operating 3oltage is QA* (C0 Through this power suppl, +ir+uit we ha3e to +reate a QA* (C whi+h is gi3en to the mi+ro +ontroller0 The below +omponents are used to +reate the power suppl,
,+te! >D* C suppl,
Step down transformer
Bridge re+tifier
Regulator Blo+- (iagram of
Power Suppl,
De".r#pt#onI >D* C suppl, is gi3en to the step down transformer of ;> t,pe0 $t ma, be a >D* to @* or ;>* step down transformer0 The output of the step down transformer is gi3en to bridge re+tifier0 The bridge re+tifier is formed with ;NH diodes0 The bridge re+tifier +on3erts the C *oltage into (C *oltage0 But the output (C *oltage +ontains some C +omponent /ripples10 So we use a +apa+itorsG>>uF:>A*4 0;uF:( and resistor of ; as a filter for remo3ing ripples0 That output (C *oltage is gi3en to the positi3e 3oltage regulator "'H?A /i0e04 H? represents the positi3e series and A represent the output 3oltage it +an pro3ide10 So the output of the regulator will be the regulated QA* (C0 To indi+ate the +ondition of the +ir+uit we pla+e a "E( at the end of the +ir+uit0
S+hemati+ of Power Suppl, 21
Vo-ta0e Re04-ator" *oltage regulators +omprise a +lass of widel, used $Cs0 Regulator $C units +ontain the +ir+uitr, for referen+e sour+e4 +omparator amplifier4 +ontrol de3i+e4 and o3erload prote+tion all in a single $C0 $C units pro3ide regulation of either a fi7ed positi3e 3oltage4 a fi7ed negati3e 3oltage4 or an ad6ustabl, set 3oltage0 fi7ed threeGterminal 3oltage regulator has an unregulated d+ input 3oltage4 *i4 applied to one input terminal4 a regulated d+ output 3oltage4 *o4 from a se+ond terminal4 with the third terminal +onne+ted to g round0 The series H? regulators pro3ide fi7ed positi3e regulated 3oltages from A to > 3olts0 Similarl,4 the series H@ regulators pro3ide fi7ed negati3e regulated 3oltages from A to > 3olts0 IC Vo-ta0e Re04-ator"
*oltage regulator $Cs are a3ailable with fi7ed /t,pi+all, A4 ;> and ;A*1 or 3ariable output 3oltages0 The, are also rated b, the ma7imum +urrent the, +an pass0 Negati3e 3oltage regulators are a3ailable4 mainl, for use in dual supplies0 'ost regulators in+lude some automati+ prote+tion from e7+essi3e +urrent /o3erload prote+tion1 and o3erheating /thermal prote+tion10 'an, of the fi7ed 3oltage regulator $Cs has D leads and loo- li-e power transistors4
LI>UID CR?STAL DIS$LA? 22
+a"#. LCD Interfa.#n0 C#r.4#t
$#n Conf#04rat#on,
$#n Conf#04rat#on of 5@%: LCD 23
VCC VSS and VEE,
5hile *CC and *SS pro3ide QA* and ground respe+ti3el,4 *EE is used for +ontrolling "C( +ontrast0 RS (REISTER SELECT!,
There are two important registers inside the "C(0 5hen RS is low /14 the data is to be treated as a +ommand or spe+ial instru+tion /su+h as +lear s+reen4 position +ursor4 et+010 5hen RS is high /;14 the data that is sent is a te7t data whi+h should be displa,ed on the s+reen0 For e7ample4 to displa, the letter T on the s+reen ,ou would set RS high0 R' (READ='RITE!,
The R5 line is the Read:5rite +ontrol line0 5hen R5 is low /14 the information on the data bus is being written to the "C(0 5hen R5 is high /;14 the program is effe+ti3el, quer,ing /or reading1 the "C(0 Onl, one instru+tion /#et "C( status1 is a read +ommand0 ll others are write +ommands4 so R5 will almost be low0 EN (ENA+LE!,
The EN line is +alled Enable0 This +ontrol line is used to tell the "C( that ,ou are sending it data0 To send data to the "C(4 ,our program should first set this line high /;1 and then set the other two +ontrol lines and:or put data on the data bus0 5hen the other lines are +ompletel, read,4 bring EN low /1 again0 The ;G transition tells the H? to ta-e the data +urrentl, found on the other +ontrol lines and on the data bus and to treat it as a +ommand0 D;DB (DATA LINES!,
The ?Gbit data pins4 (G(H are used to send information to the "C( or read the +ontent of the "C(2s internal registers0 To displa, letters and numbers4 we send SC$$ +odes for the letters GK4 aG and numbers G@ to these pins while ma-ing RS;0
24
There are also instru+tion +ommand +odes that +a n be sent to the "C( to +lear the displa, or for+e the +ursor to the home position or blin- the +ursor0 5e also use RS to +he+- the bus, flag bit to see if the "C( is read, to re+ei3e the information0 The bus, flag is (H and +an be read when R:5 ; and RS4 as followsI if R:5 ;4 RS 0 5hen (H; /bus, flag ;14 the "C( is bus, ta-ing +are of internal operations and will not a++ept an, new information0 5hen (H 4 the "C( is read, to re+ei3e new information0
LC C.MMA/ C.ES
CO(E /!E1
CO''N( TO "C( $NSTR&CT$ON RE#$STER
;
C"ER ($SP") SCREEN
>
RET&RN !O'E
(ECRE'ENT C&RSOR/S!$FT C&RSOR TO "EFT1
<
$NCRE'ENT C&RSOR/S!$FT C&RSOR TO R$#!T1
A
S!$FT ($SP") R$#!T
H
S!$FT ($SP") "EFT
?
($SP") OFF4C&RSOR OFF
($SP") OFF4C&RSOR ON
C
($SP") ON4C&RSOR OFF
E
($SP") ON C&RSOR B"$N$N#
F
($SP") ON C&RSOR B"$N$N#
;
S!$FT C&RSOR POS$T$ON TO "EFT
;
S!$FT C&RSOR POS$T$ON TO R$#!T
;?
S!$FT T!E ENT$RE ($SP") TO T!E "EFT
;C
S!$FT T!E ENT$RE ($SP") TO T!E R$#!T
?
FORCE C&RSOR TO BE#$NN$N# OF ;ST "$NE
C
FORCE C&RSOR TO BE#$NN$N# OF > N( "$NE 25
D?
?GB$T $NTERFCE4 > "$NES4 A=H P$E"S
D
?GB$T $NTERFCE4 ; "$NE4 A=H P$E"S
>?
GB$T $NTERFCE4 > "$NES4 A=H P$E"S
>
GB$T $NTERFCE4 ; "$NE4 A=H P$E"S
CS. AESSES ,. LCS 162 LC
First Row
Second Row
80
81
82
83
84
85
8
8F
C0
C1
C2
C3
C4
C5
C6
CF
I6 Sen"or"
!ere a pair of $R transmitter re+ei3er is used as sensor0 Photo transistors are used as $R re+ei3er4 sin+e it has sensiti3it, to re+ei3e $R ra,s0 IR Tran"m#tter, Infrared /IR 1 radiation is ele+tromagneti+ radiation of a wa3elength longer than that of 3isible
light4 but shorter than that of mi+rowa3es0 Ob6e+ts generall, emit infrared radiation a+ross a spe+trum of
26
wa3elengths4 but onl, a spe+ifi+ region of the spe+trum is of interest be+ause sensors are usuall, designed onl, to +olle+t radiation within a spe+ifi+ bandwidth0 Remote +ontrols and $r( de3i+es use infrared lightGemitting diodes /"E(s1 to emit infrared radiation whi+h is fo+used b, a plasti+ lens into a narrow beam0 The re+ei3er uses a sili+on photodiode to +on3ert the infrared radiation to an ele+tri+ +urrent0 $t responds onl, to the rapidl, pulsing signal +reated b, the transmitter4 and filters out slowl, +hanging infrared radiation from ambient light0 $R does not penetrate walls and so does not interfere with other de3i+es in ad6oining rooms0 $hototran"#"tor",
Phototransistors are e7amples of photodiodeGamplifier +ombinations integrated within a single sili+on ship0 These +ombinations are put together in order to o3er+ome the ma6or fault of photodiodesI unit, gain0 'an, appli+ations demand a greater output signal from photodiode +an alwa,s be amplified through use of an e7ternal opGamp or other +ir+uitr,4 this approa+h is often not as pra+ti+al or as +ost effe+ti3e as the use of phototransistors0 The phototransistor +an be 3iewed as a photodiode whose output photo+urrent is fed into the base of a +on3entional small signal transistor0 5hile not required for operation of the de3i+e as a photo dete+tor4 a base +onne+tion is often pro3ided allowing the designer the option of using base +urrent to bias the transistor0
U
+a"#." of IR tran"m#tter
$nfra red transmitter emits $R ra,s in planar wa3e front manner0 E3en though infra red ra,s spread in all dire+tions4 it propagates along straight line in forward dire+tion0 $R ra,s ha3e the +hara+teristi+s of produ+ing se+ondar, wa3elets when it +ollides with an, obsta+les in its path0 This propert, of $R is dis+ussed here0
27
0 Fig A0? $R Transmitter Cir+uit 5hen $R ra,s gets emitted from "E(4 it mo3es in the dire+tion it is angled0 5hen an, obsta+le interferes in the path4 the $R ra,s get +ut and it produ+es se+ondar, wa3elets whi+h propagates mostl, in return dire+tion or in a dire+tion opposite to that of the primar, wa3es4 whi+h produ+es the net result li-e refle+tion of $R ra,s0
+a"#." of IR re.e#er,
$nfrared photo re+ei3er is a two terminal PN 6un+tion de3i+e4 whi+h operates in a re3erse bias0 $t has a small transparent window4 whi+h allows light to stri-e the PN 6un+tion0 photodiode is a t,pe of photo dete+tor +apable of +on3erting light into either +urrent or 3oltage4 depending upon the mode of operation0 'ost photodiodes will loo- similar to a light emitting diode0 The, will ha3e two leads4 or wires4 +oming from the bottom0 28
$nfrared (ete+tors Basi+s
$R (ete+tor Spe+ifi+ations n infrared emitter is an "E( made from gallium arsenide4 whi+h emits nearGinfrared energ, at about ??nm0
The infrared phototransistor a+ts as a transistor with the base 3oltage determined b, the amount of light hitting the transistor0 !en+e it a+ts as a 3ariable +urrent sour+e0 #reater amount of $R light +ause greater +urrent to flow through the +olle+torGemitter leads0 s shown in the diagram below4 the phototransistor is wired in a similar +onfiguration to the 3oltage di3ider0 The 3ariable +urrent tra3eling through the resistor +auses a 3oltage drop in the pullGup resistor0
29
$R Pair Cir+uit
S3m1o- and t3p#.a- #e2 of phototran"#"tor,
30
Feat4re",
"owG+ost 3isible and nearG$R photo dete+tor0
3ailable with gains from ; to o3er ;A0
'oderatel, fast response times0
3ailable in a wide range of pa+-ages in+luding epo7,G+oated4 transferGmolded4 +ast4 hermeti+4 and in +hip form0
&sable with almost an, 3isible or nearGinfrared light sour+e su+h as $RE(sM neonM fluores+ent4 in+andes+ent bulbsM lasersM flame sour+esM sunlightM et+0
Same general ele+tri+al +hara+teristi+s as familiar signal transistors0
31
MOC<;:5
56 Introd4.t#on I
OptoGisolators4 or OptoG+ouplers4 are made up of a light emitting de3i+e4 and a light sensiti3e de3i+e4 all wrapped up in one pa+-age4 but with no ele+tri+al +onne+tion between the two4 6ust a beam of light0 The light emitter is nearl, alwa,s an "E(0 The light sensiti3e de3i+e ma, be a photodiode4 phototransistor4 or more esoteri+ de3i+es su+h as th,ristors4 tria+s e0t0+0
2. Opto-isolator parameters
Co--e.torem#tter o-ta0e
This is the ma7imum 3oltage that +an be present from the +olle+tor to the emitter of the re+ei3ing phototransistor /when it is turned off no light1 before it ma, brea-Gdown0 Cree pa0e d#"tan.e
This is ph,si+all, how far a spar- would ha3e to tra3el around the outside of the pa+-age to get from one side to the other0 $f the pa+-age has +ontaminants on it4 solder flu74 or dampness4 then a lowerGresistan+e path +an be +reated for noise signals to tra3el along0
For2ard .4rrent
This is the +urrent passing through the sending "E(0 T,pi+all,4 an OptoGisolator will require about A'a to turn the output transistor on0
For2ard o-ta0e
This is the 3oltage that is dropped a+ross the "E( when it is turned on0 'ost normal diodes drop about 0H34 but with "E(s it is t,pi+all, ; > 3olts0
Co--e.tor dar/ .4rrent
This is the +urrent that +an flow through the output phototransistor when it is turned off0
32
Co--e.torem#tter "at4rat#on o-ta0e
5hen the output transistor is full, turned on /saturated14 this is the 3oltage there will be between the +olle+tor and emitter0
I"o-at#on re"#"tan.e
This is the resistan+e from a pin in the input side to a pin on the output side0 $t should be 3er, high0 Re"pon"e t#me
The rise and fall times are the times that the output 3oltage ta-es to get from ero to ma7imum0 The rise time is 3er, mu+h dependant on the load resistor4 sin+e it is this that is pulling the output up0 Therefore this 3alue is alwa,s quoted with a fi7ed load resistan+e0 Note howe3er that the 3alue4 ; Ohms4 is mu+h less than ,ou are li-el, to use in pra+ti+e0 This is another of the manufa+turer2s attempts to ma-e the produ+t loo- better than it isV
C4toff fre4en.3
This is effe+ti3el, the highest frequen+, of square wa3e that +an be sent through the OptoGisolator0 $t is a+tuall, the frequen+, at whi+h the output 3oltage is onl, swinging half the amplitude than at (C le3els /GD(b half10 $t is therefore lin-ed with the rise and fall times0
C4rrent Tran"fer Rat#o (CTR!
This is the ratio of how mu+h +olle+tor +urrent in the output transistor that ,ou get gi3en a +ertain amount of forward +urrent in the input side "E(0 $t is affe+ted b, how +lose the "E( and phototransistor are inside the de3i+e4 how effi+ient the, both are4 and man, other fa+tors0 $n fa+t it is not a +onstant but 3aries wildl, with "E( forward +urrent0
33
TRIAC TR$C4 from Triode for lternating Current4 is a generalied trade name for an ele+troni+ +omponent whi+h +an +ondu+t +urrent in either dire+tion when it is triggered /turned on14 and is formall, +alled a bidire+tional triode th,ristor or bilateral triode th,ristor0 TR$C is appro7imatel, equi3alent to two +omplementar, unilateral th,ristors /one is anode triggered and another is +athode triggered SCR 1 6oined in in3erse parallel /paralleled but with the polarit, re3ersed1 and with their gates +onne+ted together0 $t +an be triggered b, either a positi3e or a negati3e 3oltage being applied to its gate ele+trode /with respe+t to ;4 otherwise -nown as 'T;10 On+e triggered4 the de3i+e +ontinues to +ondu+t until the +urrent through it drops below a +ertain threshold 3alue4 the holding +urrent4 su+h as at the end of a halfG+,+le of alternating +urrent /C1 mains power0 This ma-es the TR$C a 3er, +on3enient swit+h for C +ir+uits4 allowing the +ontrol of 3er, large power flows with milliampereGs+ale +ontrol +urrents0 $n addition4 appl,ing a trigger pulse at a +ontrollable point in an C +,+le allows one to +ontrol the per+entage of +urrent that flows through the TR$C to the load /phase +ontrol10
App-#.at#on
"ow power TR$Cs are used in man, appli+ations su+h as light dimmers4 speed +ontrols for ele+tri+ fans and other ele+tri+ motors4 and in the modern +omputeried +ontrol +ir+uits of man, household small and ma6or applian+es0 !owe3er4 when used with indu+ti3e loads su+h as ele+tri+ fans4 +are must be ta-en to assure that the TR$C will turn off +orre+tl, at the end of ea+h halfG+,+le of the C power0 snubber +ir+uit /usuall, of the RC t,pe1 is often used between ; and > to assist this turnGoff0 Snubber +ir+uits are also used to pre3ent premature triggering4 +aused for e7ample b, 3oltage spi-es in the mains suppl,0 lso4 a gate resistor or +apa+itor /or both in parallel1 ma, be +onne+ted between gate and ; to further pre3ent false triggering0 That4 howe3er4 in+reases the required trigger +urrent and : or adds laten+, /+apa+itor +harging10
For higherGpowered4 moreGdemanding loads4 two SCRs in in3erse parallel ma, be used instead of one TR$C0 Be+ause ea+h SCR will ha3e an entire halfG+,+le of re3erse polarit, 34
3oltage applied to it4 turnGoff of the SCRs is assured4 no matter what the +hara+ter of the load0 !owe3er4 due to the separate gates4 proper triggering of the SCRs is more +omple7 than triggering a TR$C0
$n addition to +ommutation4 a TR$C ma, also not turn on reliabl, with nonGresisti3e loads if the phase shift of the +urrent pre3ents a+hie3ing holding +urrent at trigger time0 To o3er+ome that4 pulse trains ma, be used to repeatedl, tr, to trigger the TR$C until it finall, turns on0 The ad3antage is that the gate +urrent does not need to be maintained throughout the entire +ondu+tion angle4 whi+h +an be benefi+ial when there is onl, limited dri3e +apabilit, a3ailable0
35
CODIN ,
Win+ludeXregA;0hY Win+ludeXstring0hY Wdefine "C(%+lear/1 "C(%+ommand/7;1 :: Clear "C( (ispla, Wdefine "C(%orgin/1"C(%+ommand/7>1 :: set to orgin "C( Wdefine "C(%row;/1 "C(%+ommand/7?1 :: Begin at ;st line Wdefine "C(%row>/1"C(%+ommand/7+1 :: Begin at >nd line 3oid "C(%+ommand/unsigned +har +ommand1M 3oid l+d%dela,/unsigned +har ms1M 3oid "C(%puts/unsigned +har =l+d%string1M 36
3oid disp/unsigned +har name;1M
sbit sensor;P;ZM
::$R Sensor $nput in+reament
sbit sensor>P;Z;M
::$R Sensor $nput de+reament
sbit rsPZM
::"+d Register Sele+t Pin
sbit enPZ>M
::"+d Enable Pin
sbit RE");PZDM
::O&TP&T "O(
sbit RE")>PZM
::O&TP&T "O(
stati+ unsigned +har +ounterM
3oid l+d%en/1
::Funtion for "C( Enable
[ en;M enM \
3oid "C(%dela,/unsigned +har ms1 ::Fun+tion for +reate Time (ela, [ unsigned int n4iM for/nMnXmsMnQQ1 37
[ for/iMiX>MiQQ1M \ \ 3oid "C(%+ommand/unsigned +har +ommand1 ::"C( Command Pass Funtion [ rsM P>+ommandM l+d%en/1M "C(%dela,/;1M \ 3oid "C(%init/1 ::"C( intialiation funtion [ "C(%+ommand/7D?1M "C(%+ommand/7<1M "C(%+ommand/7+1M "C(%+ommand/7;1M \ 3oid "C(%put+/unsigned +har as+ii1 [ rs;M 38
P>as+iiM l+d%en/1M "C(%dela,/>1M \ 3oid "C(%puts/unsigned +har =l+d%string1 [ while/=l+d%string1 [
"C(%put+/=l+d%stringQQ1M \
\ 3oid disp/unsigned +har name;1 [ rs;M P>name;M l+d%en/1M l+d%dela,/;1M \ 3oid main/1 [ RE");;M ::$N$T$"") "O5 O&TP&T 39
RE")>;M "C(%init/1M ::+all "C( initialiation fun+tion "C(%+ommand/7?1M ::"C( +ommand for displa, first line "C(%puts/*$S$TOR CO&NTER1M ::String displa, in the "C( while/;1
::Run fore3er alwa,s true
[
if/sensor;1 [ +ounterQQM
"C(%+ommand/7C1M ::"C( +ommand for displa, first line "C(%puts/CO&NTSI1M ::String displa, in the "C( [
disp///+ounter];1:;1Q?1M
disp///+ounter];1:;1Q?1M
disp///+ounter];1:;1Q?1M
disp///+ounter];1:;1Q?1M
if/+ounterY; ^^ +ounterX;1 [ 40
::limit e7+eeds +ondition
RE");M "C(%+ommand/7C1M :: "C(%puts/"$#!TS ON1M ::String displa, in the "C( \ if/+ounterY;1
::limit e7+eeds +ondition
[ RE");M RE")>M "C(%+ommand/7C1M :: "C(%puts/"$#!TS ON1M ::String displa, in the "C( \
if/+ounter1
::limit e7+eeds +ondition
[ RE");;M RE")>;M "C(%+ommand/7C1M :: "C(%puts/"$#!TS ON1M ::String displa, in the "C( \ \ \ 41
if/sensor>1 [ +ounterGGM
"C(%+ommand/7C1M ::"C( +ommand for displa, first line "C(%puts/CO&NTSI1M ::String displa, in the "C( [
disp///+ounter];1:;1Q?1M
disp///+ounter];1:;1Q?1M
disp///+ounter];1:;1Q?1M
disp///+ounter];1:;1Q?1M
if/+ounterY ^^ +ounterX;1
::limit e7+eeds +ondition
[ RE");M "C(%+ommand/7C1M :: "C(%puts/"$#!TS ON1M ::String displa, in the "C( \
42
if/+ounterY;1
::limit e7+eeds +ondition
[ RE");M RE")>M "C(%+ommand/7C1M :: "C(%puts/"$#!TS ON1M ::String displa, in the "C( \
if/+ounterY ^^ +ounterX;1
::limit e7+eeds +ondition
[ RE");M RE")>;M "C(%+ommand/7C1M :: "C(%puts/"$#!TS ON1M ::String displa, in the "C( \
if/+ounter1
::limit e7+eeds +ondition
[ RE");;M RE")>;M "C(%+ommand/7C1M 43
:: "C(%puts/"$#!TS ON1M ::String displa, in the "C( \
\
\ \ \
Software (es+ription EIL 4V#"#on is a standard 5indows appli+ation0 7EIL SO8T9ARE:
eil +ompiler is a software used where the ma+hine language +ode is written and +ompiled0 fter +ompilation4 the ma+hine sour+e +ode is +on3erted into he7 +ode whi+h is to be dumped into the mi+ro+ontroller for further pro+essing0 eil +ompiler also supports C language +ode0 STEPS TO 9RITE AN ASSEM5L; LANGUAGE PROGRAM IN 7EIL AND HO9 TO COMPILE IT:
1& st++ t*e e+ Sofw!e t*e PC y o t*e d!es& 2& Afe! st++:o' %o w++ be %!eted wt* t*e me ;e+ <#so3=& >
44
4& A ?e oes wt* de!et o:os t s*ow? t*e !oBe%t wo!@s%e t t*e +efmost %o!e! sde' o
10& H*e yo< %+%@ o y oe o t*e m%!o%ot!o++e!s' t*e et
17& ?*t %+%@ o t*e t!?et d se+e%t t*e F!st o:o ;.:os o! t!?et=& A wdow oes wt* de!et o:os +@e de%e' t!?et' o
23& C+%@ o t*s %o d ow %+%@ o t*e o:o ;#ew= d se+e%t t*e !o!te wdow to %*e%@ o! t*e o
46
Create a Project File To +reate a new pro6e+t file sele+t from the L*ision menu Pro6e+t New Pro6e+t_0 This opens a standard 5indows dialog that as-s ,ou for the new pro6e+t file name0 5e suggest that ,ou use a separate folder for ea+h pro6e+t0 )ou +an simpl, use the i+on Create New Folder in this dialog to get a new empt, folder0 Then sele+t this folder and enter the file name for the new pro6e+t4 i0e0 Pro6e+t;0 L*ision +reates a new pro6e+t file with the name PROJECT;0&*> whi+h +ontains a default target and file group name0 )ou +an see these names in the Pro6e+t 5or-spa+e Files0
Select a Device 5hen ,ou +reate a new pro6e+t L*ision as-s ,ou to sele+t a CP& for ,our pro6e+t0 The Sele+t (e3i+e dialog bo7 shows the L*ision de3i+e database0 Just sele+t the mi+ro+ontroller ,ou use0 5e are using for our e7amples the Philips ?CA;R(Q +ontroller0 This sele+tion sets ne+essar, tool options for the ?CA;R(Q de3i+e and simplifies in this wa, the tool +onfiguration0
47
On+e ,ou ha3e sele+ted a CP& from the de3i+e database ,ou +an open the user manuals for that de3i+e in the Pro6e+t 5or-spa+e Boo-s page0 These user manuals are part of the eil (e3elopment Tools C(GRO' that should be present in
,our C( dri3e00
Create New Source Files )ou ma, +reate a new sour+e file with the menu option File New0 This opens an empt, editor window where ,ou +an enter ,our sour+e +ode0 L*ision enables the C +olor s,nta7 highlighting when ,ou sa3e ,our file with the dialog File Sa3e s_ under a filename with the e7tension =0C0 5e are sa3ing our e7ample file under the name '$N0C0
48
Add and Configure the Startup Code The STRT&P0A; file is the startup +ode for the most ?A; CP& 3ariants0 The startup +ode +lears the data memor, and initialies hardware and reentrant sta+- pointers0 $n addition4 some ?A; deri3ati3es require a CP& initialiation +ode that needs to mat+h the +onfiguration of ,our hardware design0 For e7ample4 the Philips ?A;R(Q offers ,ou onG+hip 7data R' that should be enabled in the startup +ode0 Sin+e ,ou need to modif, that file to mat+h ,our target hardware4 ,ou should +op, the STRT&P0A; file from the folder CI`E$"`CA;`"$B to ,our pro6e+t folder0
Group Project Files File group allow ,ou to organie large pro6e+ts0 For the CP& startup +ode and other s,stem +onfiguration files ,ou ma, +reate a own file group in the Pro6e+t Components4 En3ironment4 Boo-s_ dialog bo70 &se the New /$nsert1 button to +reate a file group named S,stem Files0 $n the pro6e+t window ,ou ma, drag and drop the STRT&P0A; file to this new file group0
49
Now4 the Pro6e+t 5or-spa+e Files lists all items of ,our pro6e+t0 To open a file for editing4 double +li+- on the file name in the Pro6e+t 5or-spa+e0 )ou ma, need to +onfigure the startup STRT&P0A; in the editor0
Set Tool Options or Target L*ision lets ,ou set options for ,our target hardware0 The dialog Options for Target opens 3ia the toolbar i+on or 3ia the Pro6e+t G Options for Target menu item0 $n the Target tab ,ou spe+if, 50
all rele3ant parameters of ,our target hardware and the onG+hip +omponents of the de3i+e ,ou ha3e sele+ted0 The following the settings for our e7ample are shown0
uild Project and Create a !"# File T,pi+al4 the tool settings under Options Target are all ,ou need to start a new appli+ation0 )ou ma, translate all sour+e files and line the appli+ation with a +li+- on the Build Target toolbar i+on0 5hen ,ou build an appli+ation with s,nta7 errors4 L*ision will displa, errors and warning messages in the Output 5indow Build page0 double +li+- on a message line opens the sour+e file on the +orre+t lo+ation in a L*ision editor window0
51
On+e ,ou ha3e su++essfull, generated ,our appli+ation ,ou +an start debugging as des+ribed under Testing Programs with the L*ision (ebugger0 Now ,ou ma, modif, e7isting sour+e +ode or add new sour+e files to the pro6e+t0 The Build Target toolbar button translates onl, modified or new sour+e files and generates the e7e+utable file0 L*ision maintains a file dependen+, list and -nows all in+lude files used within a sour+e file0 E3en the tool options are sa3ed in the file dependen+, list4 so that L*ision rebuilds files onl, when needed0 5ith the Rebuild Target +ommand4 all sour+e files are translated4 regardless of modifi+ations0 fter ,ou ha3e tested ,our appli+ation4 it might be required to +reate an $ntel !E file and to download the appli+ation software into the ph,si+al de3 i+e using a Flash programming utilit,0 L*ision +reates !E files with ea+h build pro+ess when Create !E file under Options for Target Output is enabled0 The 'ergeD> !e7file option is a3 ailable for Code Ban-ing ppli+ations when ,ou ha3e sele+ted the E7tended "in-er "A;0 )ou ma, start ,our Flash programming utilit, after the ma-e pro+ess when ,ou spe+if, the program under the option Run &ser Program W;0
52
Con.-4"#on
The pro6e+t entitled 8*isitor Counter and Room "ight Controller9 helps to +ount number of 3isitors entering and e7iting a parti+ular passage or wa,0 The +ir+uit +ounts both entering and e7iting 3isitors and displa,s the number of 3isitors present inside the hall0 *isitor +ounting is not limited to the entr,:e7it point of a +ompan, but has a wide range of appli+ations that pro3ide information to management on the 3olume and flow of people throughout a lo+ation0 This helps to ma7imie the effi+ien+, and effe+ti3eness of emplo,ees4 floor area and sales potential of an organiation0 The +ir+uit ma, also be enhan+ed with a wide +ounting range b, modif,ing software se+tion of the s,stem0 $t +an also be enhan+ed for long and a++urate sensing range using a laser tor+h instead of $R transmission +ir+uit0 Thus the +ir+uit +an be used to monitor 3isitor flow in effe+ti3e manner4 where the 3isitors ha3e to +ounted and +ontrolled0
53
REFERENCES
5OO7S:
1 eet* &>& Ay+' The 8051 Microcontroller and its applicaons ' !e:%e *++' ew Ed:o' 2006& 2 ,!@ #*d' Embedded system design' Dt M% I!w *++' 3 Ed:o' 1995& 3 B m+' Embedded Systems' >HE' 4 Ed:o' 2000&
9E5SITES: 5 www&?oo?+e&%om 6 www&*owst<wo!@s&%om 7 www&eo!m&et 8 www&w@ed&o!?
54
