PROJECT RECORD.docx

CHAPTER- 1

PROJECT OVERVIEW

1.1Introduction Of Project

1.1.1 Project Definition:

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 life.

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.

1.1.2 Project Overview:

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

GOVT.POLYTECHNIC COLLEGE Page 1

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 DESCRIPTION

2.1 Basic Block Diagram:

Enter Exit

LCD INTERFACING

Fig. 2.1 Basic Block Diagram


Enter Sensor

Exit Sensor

Power Supply

Signal Conditioning

AT89S52

Light

Relay DriverSignal Conditioning

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 essential blocks.

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 manufactured using Atmel’s

high-density nonvolatile 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 conventional

nonvolatile memory programmer. By 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 cost

effective solution so many embedded control applications.

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.


CHAPTER- 3

SCHEMATIC DIAGRAM

3.1 Transmission Circuit:-

Fig. 3.1 Transmitter circuit

CIRCUIT DESCRIPTION:


There are two main parts of the circuits.

1. Transmission Circuits (Infrared LEDs)

2. Receiver Circuit (Sensors)

1. Transmission Circuit:

Fig. 3.2 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.

3.2 Receiver Circuit:

Fig. 3.3 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 7-Segment 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.


CHAPTER – 4

HARDWARE DESIGN & DESCRIPTIONS

Hardware Design:-

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.


MicrocontrollerAT89S52

Infrared SensorTSOP1738

7-SegmentDisplay

RelayTimer IC555

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

7-Segment Display

4.3 Description of Components

4.3.1 Microcontroller AT89S52:

The AT89S52 is a low-power, high-performance CMOS 8-bit

microcontroller with 8K bytes of in-system programmable Flash memory. The

device is manufactured using Atmel’s high-density 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 two-level 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.

FEATURES:-

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

Description:

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.

Features:

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


Block Diagram:

Fig. 4.3 Block Diagram of TSOP 1738

Application Circuit:

Fig. 4.4 Application circuit

4.3.3 555 ( TIMER IC):

Fig. 4.5 Timer IC(555)

Description:


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.

Features:

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

Applications:

Precision timing

Pulse generation

Sequential timing

Time delay generation

Pulse width modulation

Pulse position modulation

Linear ramp generator

4.3.4 LTS 542 (7-Segment Display)

Description:


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

Features:

Common Anode

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

Description:

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.

Features:

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

SOFTWARE DESIGN

FLOW CHART:

Fig. 5.1 Flow Chart


StartInfrared Signal

Transmission

Interrupted

from Sensor1

Interrupted

from Sensor 2

Turn On

RelayCounte

r Incremented

Counter

Decremented

Counter set to

0

Relay Turn Off

Turn On

Light

Turn Off

Light

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 off.


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

FUTURE EXPANSION

FUTURE EXPANSION

By using this circuit and proper power supply we can implement various

applications

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.


CHAPTER - 8

APPLICATIONS, ADVANTAGES & DISADVANTAGES

Application

o For counting purposes

o For automatic room light control

Advantages

o Low cost

o Easy to use

o Implement in single door

Disadvantages

o It is used only when one single person cuts the rays of the

sensor hence it cannot be used when two person cross

simultaneously.


Reference Books

Programming in ANSI C: E BALAGURUSAMY

The 8051microcontroller and embedded systems: MUHAMMAD ALI MAZIDI

JANICE GILLISPIE MAZIDI

The 8051 microcontroller: KENNETH J. AYALA

Website

www.datasheets4u.com

www.8051.com


http://www.8051.com/

http://www.datasheets4u.com/

Documents

PROJECT RECORD.docx