A PROJECT REPORT ON
AUTOMATIC ROOM LIGHT CONTROLLER
WITH VISITOR COUNTER
IN THE PARTIAL FULFILMENT OF THE REQUIRMENT FOR THE DEGREE
BACHELOR OF TECHNOLOGY
ELECTRICAL AND ELECTRONICS ENGINEERING
Under the guidance of
INDRAPRASTHA ENGINEERING COLLEGE
TABLE OF CONTENT
Component used- Part A
Component used-Part B
555 integrated circuit
IC-555 Astable operation
Schematic for constant HV power supply
Telemetry circuit explanation
Working of telephone cradle switch
Dual tone multiple frequency encoder
Working of system
C program embedded code
This is to certify that Project Report entitled ―AUTOMATIC
VISITOR COUNTER ‖ that is submitted by MOHIT AWASTHI in
partial fulfillment of the requirement for the award of the degree
B.Tech in Department of ELECTRICAL AND ELECTRONICS of
G.B technical University, is a record of the candidate own work
carried out by him under my own supervision. The matter embodies
in thesis is original and has not been submitted for the award of any
The fear of theft and burglary always annoys many people. When lock and keys
become less safe, one can seek the help of electronic security systems.
Such a portable security system is described here.
This electronic setup auto activated whenever the intruder enters to the
unauthorized no entry area. It auto activate the landline number and redial the last
dialed number from the conventional telephone. All we need is to do minor
changes to activate this telephone as it works as to become auto dialer circuit.
Thus whenever the intruder enters to the area, it activates the sensor circuit
of either sound activation or infrared light beam obstruction circuit, the redial
circuit become active and give a ring tone to the receiving end. It may be a mobile
phone or any landline phone or even police control room.
I hereby declare that this submission is own work and that, to the best of my
knowledge and belief, it contains no material previously published or written by
another person nor material which to a substantial extend has been accepted for the
award of the award of any other degree or diploma of the university or other
institute of the higher leaning except where due acknowledgement has been made
in the text.
First and foremost, I am deeply indebted to my mentor Ast. Prof. SATYJEET DAS
who inspiration has been unfailingly available to me at all stages of my training.
This has fueled my enthusiasm even further and encouraged me to boldly step into
what was a totally dark and unexplored expanse before me.
I would like to thank Prof. Y.K SAH for his efforts, who was always ready with a
positive comment, whether it was an off-hand comment to encourage me or
constructive piece of criticism.
In course of present work it has been my privilege to receive help and assistance of
my friends. I take great pleasure in acknowledge my debt to them.
I wish to thank my parents for their undivided support and interest who inspired
me and encouraged me to go my own way, without whom I would be unable to
complete my project. At last but not the least I want to thank my friends who
appreciated me for my work and motivated me and finally to God who made all the
CHAPTER :- 1
1. Introduction Of Project
Project title is ―AUTOMATIC ROOM LIGHT CONTROLLER
WITH BIDIRECTIONAL VISITOR COUNTER ―.
The objective of this project is to make a controller based model
to count number of persons visiting particular room and accordingly
light up the room. Here we can use sensor and can know present
number of persons.
In today’s world, there is a continuous need for automatic
appliances with the increase in standard of living, there is a sense of
urgency for developing circuits that would ease the complexity of
Also if at all one wants to know the number of people present in
room so as not to have congestion. This circuit proves to be helpful.
This Project ―Automatic Room Light Controller with Visitor
Counter using Microcontroller is a reliable circuit that takes over the
task of controlling the room lights as well us counting number of
persons/ visitors in the room very accurately. When somebody enters
into the room then the counter is incremented by one and the light in the
room will be switched ON and when any one leaves the room then the
counter is decremented by one. The light will be only switched OFF
until all the persons in the room go out. The total number of persons
inside the room is also displayed on the seven segment displays.
The microcontroller does the above job. It receives the signals
from the sensors, and this signal is operated under the control of
software which is stored in ROM. Microcontroller AT89S52
continuously monitor the Infrared Receivers, When any object pass
through the IR Receiver's then the IR Rays falling on the receiver are
obstructed , this obstruction is sensed by the Microcontroller
CHAPTER :- 2
BLOCK DIAGRAM AND ITS
2.1 Basic Block Diagram
Fig. 2.1 Basic Block Diagram
2.2 Block Diagram Description
The basic block diagram of the bidirectional visitor
counter with automatic light controller is shown in the above
figure. Mainly this block diagram consist of the following
1. Power Supply
2. Entry and Exit sensor circuit
3. AT 89S52 micro-controller
4. Relay driver circuit
1. Power Supply:Here we used +12V and +5V dc power supply. The
main function of this block is to provide the required amount
of voltage to essential circuits. +12 voltage is given. +12V is
given to relay driver. To get the +5V dc power supply we
have used here IC 7805, which provides the +5V dc
regulated power supply.
2. Enter and Exit Circuits:This is one of the main part of our project. The main
intention of this block is to sense the person. For sensing the
person and light we are using the light dependent register
(LDR). By using this sensor and its related circuit diagram
we can count the persons.
3. 89S52 Microcontroller:It is a low-power, high performance CMOS 8-bit
microcontroller with 8KB of Flash Programmable and
Erasable Read Only Memory (PEROM). The device is
memory technology and is compatible with the MCS-51TM
instruction set and pin out. The on-chip Flash allows the
program memory to be reprogrammed in-system or by a
combining a versatile 8-bit CPU with Flash on a monolithic
hip, the Atmel AT89S52 is a powerful
Microcontroller, which provides a highly flexible and
4. Relay Driver Circuit:-
This block has the potential to drive the various
controlled devices. In this block mainly we are using the
transistor and the relays. One relay driver circuit we are using
to control the light. Output signal from AT89S52 is given to
the base of the transistor, which we are further energizing the
particular relay. Because of this appropriate device is selected
and it do its allotted function.
There are two main parts of the circuits.
1. Transmission Circuits (Infrared LEDs)
2. Receiver Circuit (Sensors)
1. Transmission Circuit:
Fig. 3.3 Transmitter circuit
This circuit diagram shows how a 555 timer IC is
configured to function as a basic monostable multivibrator.
A monostable multivibrator is a timing circuit that changes
state once triggered, but returns to its original state after a
certain time delay. It got its name from the fact that only one
of its output states is stable. It is also known as a 'one-shot'.
In this circuit, a negative pulse applied at pin 2 triggers
an internal flip-flop that turns off pin 7's discharge transistor,
allowing C1 to charge up through
R1. At the same time, the flip-flop brings the output
(pin 3) level to 'high'. When capacitor C1 as charged up to
about 2/3 Vcc, the flip-flop is triggered once again, this time
making the pin 3 output 'low' and turning on pin 7's discharge
transistor, which discharges C1 to ground. This circuit, in
effect, produces a pulse at pin 3 whose width t is just the
product of R1 and C1, i.e., t=R1C1.
IR Transmission circuit is used to generate the
modulated 36 kHz IR signal. The IC555 in the transmitter
side is to generate 36 kHz square wave. Adjust the preset in
the transmitter to get a 38 kHz signal at the o/p. around 1.4K
we get a 38 kHz signal. Then you point it over the sensor and
its o/p will go low when it senses the IR signal of 38 kHz.
2. Receiver Circuit:
Fig. 3.4 Receiver circuit
The IR transmitter will emit modulated 38 kHz IR
signal and at the receiver we use TSOP1738 (Infrared
Sensor). The output goes high when the there is an
interruption and it return back to low after the time period
determined by the capacitor and resistor in the circuit. I.e.
around 1 second. CL100 is to trigger the IC555 which is
configured as monostable multivibrator. Input is given to the
Port 1 of the microcontroller. Port 0 is used for the 7Segment display purpose. Port 2 is used for the Relay Turn
On and Turn off Purpose.LTS 542 (Common Anode) is used
for 7-Segment display. And that time Relay will get Voltage
and triggered so light will get voltage and it will turn on. And
when counter will be 00 that time Relay will be turned off.
Reset button will reset the microcontroller.
Fig. 4.1 Snap of the entire circuit
4.1 Procedure Followed While Designing:
In the beginning I designed the circuit in DIPTRACE software.
Dip trace is a circuit designing software. After completion of the
designing circuit I prepared the layout.
Then I programmed the microcontroller using TOPVIEW
SIMULATOR software using hex file.
Then soldering process was done. After completion of the
soldering process I tested the circuit.
Still the desired output was not obtained and so troubleshooting
was done. In the process of troubleshooting I found the circuit aptly
soldered and connected and hence came to conclusion that there was
error in programming section which was later rectified and the
desired results were obtained.
4.2 List of Components:
Following is the list of components that are necessary to build the
assembly of the Digital Speedometer Cum Odometer:
Microcontroller – AT89S52
IC – 7805
Sensor – TSOP 1738 (Infrared Sensor)
Transformer – 12-0-12, 500 mA
Preset – 4.7K
Disc capacitor – 104,33pF
Reset button switch
Rectifier diode – IN4148
Transistor – BC 547, CL 100
Description of Components
4.3.1 Microcontroller AT89S52:
The AT89S52 is a low-power, high-performance CMOS 8bit microcontroller with 8K bytes of in-system programmable
Flash memory. The device is manufactured using Atmel’s highdensity nonvolatile memory technology and is compatible with the
Industry-standard 80C51 instruction set and pin out. The on-chip
Flash allows the program memory to be reprogrammed in-system
or by a conventional nonvolatile memory pro- grammar. By
combining a versatile 8-bit CPU with in-system programmable
Flash on a monolithic chip, the Atmel AT89S52 is a powerful
microcontroller which provides a highly-flexible and cost-effective
solution to many embedded control applications.
The AT89S52 provides the following standard features: 8K
bytes of Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer,
two data pointers, three 16-bit timer/counters, a six-vector twolevel interrupt architecture, a full duplex serial port, on-chip
oscillator, and clock circuitry. In addition, the AT89S52 is
designed with static logic for operation down to zero frequency
and supports two software selectable power saving modes. The
Idle Mode stops the CPU while allowing the RAM, timer/counters,
serial port, and interrupt system to continue functioning. The
Power-down mode saves the RAM con- tents but freezes the
oscillator, disabling all other chip functions until the next interrupt
or hardware reset.
8 KB Reprogrammable flash.
32 Programmable I/O lines.
16 bit Timer/Counter—3.
8 Interrupt sources.
Power range: 4V – 5.5V
Endurance : 1000 Writes / Erase cycles
Fully static operation: 0 Hz to 33 MHz
Three level program memory lock
Power off flag
Full duplex UART serial channel
Low power idle and power down modes
Interrupt recovery from power down modes
256 KB internal RAM
Dual data pointer
4.3.2 TSOP1738 (INFRARED SENSOR)
Fig. 4.2 Infrared Sensor
The TSOP17.. – Series are miniaturized receivers for infrared
remote control systems. PIN diode and preamplifier are assembled
on lead frame, the epoxy package is designed as IR filter. The
demodulated output signal can directly be decoded by a
microprocessor. TSOP17.. is the standard IR remote control
receiver series, supporting all major transmission codes.
Photo detector and preamplifier in one package
Internal filter for PCM frequency
Improved shielding against electrical field disturbance
TTL and CMOS compatibility
Output active low
Low power consumption
High immunity against ambient light
Continuous data transmission possible (up to 2400 bps)
Suitable burst length .10 cycles/burst
Fig. 4.3 Block Diagram of TSOP 1738
Fig. 4.4 Application circuit
4.3.3 555 ( TIMER IC):
Fig. 4.5 Timer IC(555)
The LM555 is a highly stable device for generating accurate
time delays or oscillation. Additional terminals are provided for
triggering or resetting if desired. In the time delay mode of
operation, the time is precisely controlled by one external resistor
and capacitor. For astable operation as an oscillator, the free
running frequency and duty cycle are accurately controlled with
two external resistors and one capacitor. The circuit may be
triggered and reset on falling waveforms, and the output circuit can
source or sink up to 200mA or drive TTL circuits.
Direct replacement for SE555/NE555
Timing from microseconds through hours
Operates in both astable and monostable modes
Adjustable duty cycle
Output can source or sink 200 mA
Output and supply TTL compatible
Temperature stability better than 0.005% per °C
Normally on and normally off output
Available in 8-pin MSOP package
Time delay generation
Pulse width modulation
Pulse position modulation
Linear ramp generator
4.3.4 LTS 542 (7-Segment Display)
The LTS 542 is a 0.52 inch digit height single digit
seven-segment display. This device utilizes Hi-eff. Red LED
chips, which are made from GaAsP on GaP substrate, and
has a red face and red segment.
Fig. 4.6 7 Segment
0.52 Inch Digit Height
Continuous Uniform Segments
Low power Requirement
Excellent Characters Appearance
High Brightness & High Contrast
Wide Viewing Angle
4.3.5 LM7805 (Voltage Regulator)
Fig. 4.7 Voltage Regulator
The KA78XX/KA78XXA series of three-terminal
positive regulator are available in the TO-220/D-PAK
package and with several fixed output voltages, making them
useful in a wide range of applications. Each type employs
internal current limiting, thermal shut down and safe
operating area protection, making it essentially indestructible.
If adequate heat sinking is provided, they can deliver over 1A
output current. Although designed primarily as fixed voltage
regulators, these devices can be used with external
components to obtain adjustable voltages and currents.
Output Current up to 1A
Output Voltages of 5, 6, 8, 9, 10, 12, 15, 18, 24V
Thermal Overload Protection
Short Circuit Protection
Output Transistor Safe Operating Area Protection
4.3.6 RELAY CIRCUIT:
Fig. 4.8 Relay
A single pole dabble throw (SPDT) relay is connected
to port RB1 of the microcontroller through a driver transistor.
The relay requires 12 volts at a current of around 100ma,
which cannot provide by the microcontroller. So the driver
transistor is added. The relay is used to operate the external
solenoid forming part of a locking device or for operating
any other electrical devices. Normally the relay remains off.
As soon as pin of the microcontroller goes high, the relay
operates. When the relay operates and releases. Diode D2 is
the standard diode on a mechanical relay to prevent back
EMF from damaging Q3 when the relay releases. LED L2
indicates relay on.
CHAPTER :- 5
Fig. 4.7 Flow Chart
If the sensor 1 is interrupted first then the microcontroller
will look for the sensor 2. And if it is interrupted then the
microcontroller will increment the count and switch on the
relay, if it is first time interrupted.
If the sensor 2 is interrupted first then the microcontroller
will look for the sensor 1. And if it is interrupted then the
microcontroller will decrement the count.
When the last person leaves the room then counter goes to 0
and that time the relay will turn off. And light will be turn
;p2.0 lcd control
;p2.1 lcd control
;p2.5 lcd control
;OBJECTIVE: TO PREPARE A AUTO_CONTROLLED ROOM
CHAPTER :- 6
TESTING AND RESULTS
Testing And Results
We started our project by making power supply. That is easy for
me but when we turn toward the main circuit, there are many problems
and issues related to it, which we faced, like component selection, which
components is better than other and its feature and cost wise a We
started our project by making power supply. That is easy for me but
when I turn toward the main circuit, there are many problems and issues
related to it, which are I faced, like component selection, which
components is better than other and its feature and cost wise also, then
refer the data books and other materials related to its.
I had issues with better or correct result, which I desired. And also
the software problem.
I also had some soldering issues which were resolved using
continuity checks performed on the hardware.
We had issues with better or correct result, which we desired. And
also the software problem.
We also had some soldering issues which were resolved using
continuity checks performed on the hardware.
We started testing the circuit from the power supply. There we got
over first trouble. After getting 9V from the transformer it was not
converted to 5V and the circuit received 9V.
As the solder was shorted IC 7805 got burnt. So we replaced the
IC7805.also the circuit part around the IC7805 were completely
damaged..with the help of the solder we made the necessary paths.
CHAPTER :- 7
By using this circuit and proper power supply we can implement
Such as fans, tube lights, etc.
By modifying this circuit and using two relays we can achieve a
task of opening and closing the door.
o For counting purposes
o For automatic room light control
o Low cost
o Easy to use
o Implement in single door
o It is used only when one single person cuts the rays of the
sensor hence it cannot be used when two person cross
CHAPTER :- 8
Programming in ANSI C: E BALAGURUSAMY
MUHAMMAD ALI MAZIDI
The 8051 microcontroller: KENNETH J. AYALA