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MINOR PROJECT REPORT
ENVIRONMENT MONITORING SYSTEM
SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS
FOR THE AWARD OF DEGREE OF BACHELOR OF TECHNOLOGY
IN
ELECTRONICS AND COMMUNICATION ENGINEERING
Guide:Mr. B.K.Singh Submitted By:
Ashwani Kumar Saxena (07614802810)
Rishabh Chopra(05696402810)
Rohit Gupta(07514802810)
MAHARAJA AGRASEN INSTITUTE OF TECHNOLOGY
SECTOR-22, ROHINI, DELHI-110086.
AFFILIATED TO
GURU GOBIND SINGH INDRAPRASTHA UNIVERSITY, NEW DELHI-110078
(2010-2014)
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Certificate
This is to certify that the Minor Project Report (ETEC 459) entitled Environment Monitoring
System done by team comprising of Ashwani Kumar Saxena (07614802810), Rishabh Chopra
(05696402810) and Rohit Gupta (07514802810) is an authentic work carried out by them under
my guidance. The matter embodied in this minor project work has not been submitted earlier for
the award of any degree or diploma to the best of my knowledge and belief.
Date: Name of the Guide: Mr. B. K. Singh
Designation
Address
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ACKNOWLEDGEMENT
We would like to articulate our profound gratitude and indebtedness to our project guide Mr.
B. K. Singh, who has always been a constant motivation and guiding factor throughout the
project time in and out as well. It has been a great pleasure for us to get an opportunity to
work under him and complete the project successfully. We wish to extend our sincere thanks
to Prof. R S Gupta, Head of Department, for approving our project work with great interest.
An undertaking of this nature could never have been attempted with our reference to and
inspiration from the works of others whose details are mentioned in references section. We
acknowledge our indebtedness to all of them.
Ashwani Kumar Saxena (07514802810)
Rishabh Chopra (05696402810)
Rohit Gupta (07514802810)
mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]8/13/2019 Environment Monitoring Display
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ABSTRACT
Motivation:
A comfortable environment can increase the productivity multi-folds. So it is important that
the environment variables such as temperature, relative humidity and light intensity are
continuously monitored and corresponding systems adjusted to maintain a comfortable
working environment.
What We Thought:
If a microcontroller based development system is provided with sensors such as Temperature
sensor, Humidity sensor and Light dependent resistor to measure the present values of
temperature, relative humidity and light intensity respectively; microcontroller can then
control the output values sent to various devices such as fans, AC, bulbs, tube lights. In this
way, all these controlled devices will work collectively to bring the environment to our
comfort level.
Goal:
The goal of this work is to develop an environment monitoring system that senses these
parameters and performs various functions such as showing the present values on LCD
screen, analog and digital controlling of various devices.
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CONTENTS
Certificate 2
Acknowledgement 3
Abstract 4List of figures 6
List of tables 7
Chapter 1. Introduction 81.1 What do we want to change? 8
1.2 Basic Details 9
1.3 Advantages 10
1.4 Applications 10
Chapter 2. Components Used 122.1 Microcontroller 12
2.2 Sensors 16
2.2.1 Temperature sensor 16
2.2.2 Light sensor 17
2.2.3 Humidity sensor 18
2.3 LED dot matrix 19
2.4 LCD 20
2.5 Relay 22
Chapter 3. Hardware Interfacing 24
3.1 Detailed Block Diagram 243.2 Components controlled by sensors 25
3.3 Circuit diagram 26
3.4 Components details 27
Chapter 4. Source Code 28
Chapter 5. Outputs Catalogue 325.1 Light parameter output 32
5.2 Temperature parameter output 36
5.3 Humidity parameter output 38
Conclusion 39
References 40
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LIST OF FIGURES
FI GURE NO. PAGE NO. DETAI LS
1 8 Fan and its regulator2 8 Lights in a room
3 9 Block diagram
4 10 Intelligent homes
5 10 Industries
6 11 Remote areas
7 11 Cool cabin-Google
8 13 Pin diagram of Atmega16
9 13 Atmega16 architecture
10 16 Thermocouple vs thermistor vs I.C. sensor
11 16 LM 35
12 16 LM 35 pin out
13 17 Photoresistor symbol
14 17 NORP12
15 17 Circuit diagram of NORP12
16 18 SY-HS-220
17 18 SY-HS-220 characteristics
18 19 LED dot matrix
19 20 LCD pin out
20 21 Generating character code
21 22 Block diagram of relay
22 22 Relay ON23 23 Relay OFF
24 24 Detailed block diagram25 26 Circuit diagram26 32 LCD showing SUNLIGHT27 32 2*2 display on LED dot matrix28 32 Bulb OFF29 33 LCD showing BRIGHT
30 33 4*4 display on LED dot matrix31 33 Bulb OFF32 34 LCD showing DIM33 34 6*6 display on LED dot matrix34 34 Bulb ON35 35 LCD showing DARK36 35 8*8 display on LED dot matrix
37 35 Bulb ON38 36 LCD showing 24oC temperature39 36 Fan OFF40 37 LCD showing 28oC temperature41 37 Fan ON42 38 LCD showing 30% relative humidity
43 38 LCD showing 70% relative humidity
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LIST OF TABLES
TABLE NO. PAGE NO. DETAI LS
1 12 Types of megaAVR microcontrollers
2 25 Components controlled by sensors3 27 Components in circuit diagram
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Chapter 1. INTRODUCTION
What Do We Want To Change?
Fig.1 Fan and its regulator
Fig.2 Lights in a room
What if all these lights know when to get lightened up themselves!
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Basic Details:
The environment monitoring system consists of a microcontroller, few sensors and controlled
devices.
Sensors include
Light sensor Temperature sensor Humidity sensor
LCD display will continuously display the current values of environment variables.
Fig.3
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Advantages:
Power consumption by controlled devices is optimum. Removes the need of constant manual monitoring. Makes the process computerized thus reducing the probability of errors. Beneficial for monitoring remote areas.
Applications:
1. Intelligent Homes
Fig.4
A home where when you enter lights lighten up themselves, fans will start rotating, if its hot,
fans will themselves rotate faster, if its humid, AC will itself take the charge is what
everybody want. And advancements done to this project can lead to all this.
2. Hazardous Industries
Fig.5
No one will like to enter a laboratory where nuclear reaction is going on or some exothermic
reaction is going on. Our system can help in maintaining the optimum environment in all
such areas.
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3. Remote Areas Monitoring
Fig.6
If you are at your base office and you need to maintain the environment in your plant in someremote area, what else can you think of except our system that can itself maintain the
environment and can let you decide the environment to be maintained.
4. Cool Office Cabins
Fig.7
A good company is not where you can see everyone busy at his table with some file, a good
company is where they all can talk, enjoy and when they will work for just an hour with a
better understanding and satisfaction, they can give what those busy people cant in whole
day!
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Chapter 2. COMPONENTS USED
MICROCONTROLLER
AVR M icrocontroller:
AVR was developed in the year 1996 by Atmel Corporation. The architecture of AVR was
developed by Alf-Egil Bogen and Vegard Wollan. AVR derives its name from its developers
and stands for Alf-Egil Bogen Vegard Wollan RISC microcontroller. The AT90S8515 was
the first microcontroller which was based on AVR architecture however the first
microcontroller to hit the commercial market was AT90S1200 in the year 1997.
AVR microcontrollers are available in four different categories:
TinyAVRLess memory, small size, suitable only for simpler applications. MegaAVRThese are the most popular ones having good amount of memory (upto256 KB), higher number of inbuilt peripherals and suitable for moderate to complex
applications.
XmegaAVR Used commercially for complex applications, which require largeprogram memory and high speed.
Application-specific AVR - MegaAVRs with special features not found on the othermembers of the AVR family, such as LCD controller, USB controller, advanced
PWM, CAN etc.
Types of MegaAVR microcontrollers:
Part Name ROM RAM EEPROM InterruptsOperation
Voltage
Operating
frequencyPackaging
ATmega8 8KB 1KB 512B 19 4.5-5.5 V0-16
MHz28
ATmega8L 8KB 1KB 512B 19 2.7-5.5 V 0-8 MHz 28
ATmega16 16KB 1KB 512B 21 4.5-5.5 V0-16
MHz 40
ATmega16L 16KB 1KB 512B 21 2.7-5.5 V 0-8 MHz 40
ATmega32 32KB 2KB 1KB 21 4.5-5.5 V0-16
MHz40
ATmega32L 32KB 2KB 1KB 21 2.7-5.5 V 0-8 MHz 40
Table 1
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Atmega16 M icrocontrol ler:
Figure 8
Atmega16 Ar chitecture:
Figure 9
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I/O PortsAtmega16 has four (PORTA, PORTB, PORTC and PORTD) 8-bitinput-output ports.
Internal Calibrated Oscillatoro
Atmega16 is equipped with an internal oscillator for driving its clock.o By default Atmega16 is set to operate at internal calibrated oscillator of 1
MHz.
o The maximum frequency of internal oscillator is 8MHz.o Alternatively, ATmega16 can be operated using an external crystal oscillator
with a maximum frequency of 16MHz. In this case, we need to modify the
fuse bits.
ADC Interfaceo Atmega16 is equipped with an 8 channel ADC (Analog to Digital
Converter).
o ADC reads the analog input for e.g., a sensor input and converts it into digitalinformation which is understandable by the microcontroller.
Timers/Counterso Atmega16 consists of two 8-bit and one 16-bit timer/counter.o Timers are useful for generating precision actions for e.g., creating time delays
between two operations.
Watchdog TimerWatchdog timer is present with internal oscillator. Watchdog timer continuously
monitors and resets the controller if the code gets stuck at any execution action for
more than a defined time interval.
InterruptsAtmega16 consists of 21 interrupt sources out of which four are external. The
remaining are internal interrupts which support the peripherals like USART, ADC,
timers etc.
USARTIt is available for interfacing with external device capable of communicating serially
(data transmission bit by bit).
Memory:Atmega16 consist of three different memory sections:1. Flash EEPROM:
o Flash EEPROM or simple flash memory is used to store the programdumped or burnt by the user on to the microcontroller.
o It can be easily erased electrically as a single unit.
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o Flash memory is non-volatile i.e., it retains the program even if thepower is cut-off.
o Atmega16 is available with 16KB of in system programmable FlashEEPROM.
2.
Byte Addressable EEPROM:o This is also a non volatile memory used to store data like values of
certain variables.
o Atmega16 has 512 bytes of EEPROM, this memory can be useful forstoring the lock code if we are designing an application like electronic
door lock.
3. RAM:o Random Access Memory, this is the volatile memory of
microcontroller i.e., data is lost as soon as power is turned off.
o Atmega16 is equipped with 1KB of internal RAM.o A small portion of RAM is set aside for general purpose registers used
by CPU and some for the peripheral subsystems of the microcontroller.
ISPAVR family of controllers have In System Programmable Flash Memory which can
be programmed without removing the IC from the circuit, ISP allows to reprogram the
controller while it is in the application circuit.
SPI (Serial Peripheral Interface)SPI port is used for serial communication between two devices on a common clock
source. The data transmission rate of SPI is more than that of USART.
TWI (Two Wire Interface)can be used to set up a network of devices, many devices can be connected over TWI
interface forming a network, the devices can simultaneously transmit and receive and
have their own unique address.
DACAtmega16 is also equipped with a Digital to Analog Converter (DAC) interface
which can be used for reverse action performed by DAC. DAC can be used whenthere is a need of converting a digital signal to analog signal.
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SENSORS
1. Temperature Sensor
What Is Integrated Circuit Temperature Sensor?A two/three terminal integrated circuit temperature transducer that produces an output
current/voltage proportional to absolute temperature in Kelvin or Centigrade.
Why it is preferred over thermistors and thermocouples?
Linearity Low cost No additional circuit required
Figure 10
Temperature Sensor used - LM35
Figure 11 Figure 12
They use the fact as temperature increases, the voltage across a diode increases at aknown rate. Technically, this is actually the voltage drop between the base and emitter
Vbeof a transistor.
Voltage at pin in mV = (reading fr om ADC) *(5000/1024) Centigrade temperature = (analog voltage in mV) / 2 The temperature Sensor is interfaced to the microcontroller as analog sensor.
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FEATURES: calibrated directly in Celsius Linear scale +10 mV/C 0.5C accuracy Temperature range -55 to 150 C
2. Light Sensor
A photoresistoror light dependent resistor(LDR) is a resistor whoseresistance decreases with increasing incident light intensity.
A photoresistor is made of a high resistance semiconductor. If light falling on thedevice is of high enough frequency, photons absorbed by the semiconductor give
bound electrons enough energy to jump into the conduction band. The resulting free
electron (and its hole partner) conduct electricity, thereby lowering resistance.
Figure 13
Light Sensor usedNORP12 (Light Dependent Resistor)
Figure 14 Figure 15
It has a high resistance in the dark, and a low resistance in the light. LDR response is not linear, in general there is a larger resistance change at brighter
light levels.
FEATURESo linear resistance variationo temperature range -60C to 75Co cheap
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3. Humidity Sensor
Humidity is the presence of water in air. The amount of water vapor in air can affecthuman comfort as well as many manufacturing processes in industries.
Humidity sensor converts relative humidity to corresponding voltage. Relative humidity is ratio of actual vapor pressure to saturated vapor pressure
expressed in %.
Substance used possesses the property of hygroscopy i.e. ability of a substance toattract and hold water molecules from the surrounding environment.
Humidity Sensor used: SY-HS-220
Figure 16 Figure 17
FEATURES
Accuracy + 5% Humidity range : 30 to 90 % Temperature range : -30 to 85 C in-built driver circuit
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LED DOT MATRIX
Figure 18
It is a matrix of LEDs. All the anode terminals of a row LEDs are connected together and taken out as 1
pin.
Similarly, all cathodes of a column LEDs are connected together and taken out as1 pin.
In case of a 8X8 LED dot matrix, we have 8 pins for the 8 rows and 8 pins for 8columns. There are 64 LEDs in this matrix.
We use one PORT for controlling the rows and one PORT for controlling thecolumns.
For selecting a row we give 1 to that row and the rest rows are passed 0.Similarly, for selecting a column we give 0 the corresponding pin and the rest
columns are passed 1.
Thus, if we want to glow the LED in 2ndrow and 5thcolumn, we write:PORTB=0b00000010; //for rowsPORTC=0b11101111; //for columns
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LCD (LIQUID CRYSTAL DISPLAY)
The devices used for displaying. They have 1 or 2 embedded microcontrollers and support at most of 80 characters. LCD contains three memory areas:
DDRAM- Display Data RAM to store display data represented in 8-bitcharacter codes.
CGROM- Character Generator ROM to generate 5 x 8 dot or 5 x 10dot character patterns from 8-bit character codes.
CGRAM-Character Generator RAM to create custom characters inLCD.
It has 2 registers which are used as buffer - Instruction Register (IR) and Data register(DR).
Selection is done by the RS pin of the LCD.o When RS=0, the LCD microcontroller treats the values on the data pin as
instruction input and stores them in IR.
o When RS=1, the LCD microcontroller treats the values on the data pin as Datainput and stores them in DR.
Figure 19
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Generating Character Code
Figure 20
int main()
{ // configure the LCDLCD_cmd(0x40);
/* bringing the cursor to the initial CGRAM address to store the character.
The character codes are being passed one by one after this. The cursor gets
incremented automatically.*/
LCD_write(0x00);
LCD_write(0x04);
LCD_write(0x0e);
LCD_write(0x0e);
LCD_write(0x0e);
LCD_write(0x1f);
LCD_write(0x04);LCD_write(0x00);
LCD_cmd(0x80);
/* bringing the cursor back to the DDRAM address for printing the
character.*/
LCD_write(0);
return 0;
}
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RELAY
Relay is used to connect bulband fan. Relay is a type of switch which is connected/ operated in one circuit and they control
the flow of current in other circuit. In other words, they allow a small current flow
circuit to control a higher current circuit.
Figure 21
Relay Design: All relays operate using the same basic principle. Relays have two circuits:
o A control circuit (shown in GREEN)o A load circuit (shown in RED).
The control circuit has a small control coil while the load circuit has a switch. The coil controls the operation of the switch.
Relay Operation: When no voltage is applied to pin 1, there is no current flow through the coil. No current means no magnetic field is developed, and the switch is open. When voltage is supplied to pin 1, current flow though the coil creates the magnetic
field needed to close the switch allowing continuity between pins 2 and 4.
Relay Energized (ON): Current flowing through the control circuit coil (pins 1 and 3) creates a small
magnetic field which causes the switch to close, pins 2 and 4.
The switch, which is part of the load circuit, is used to control an electrical circuit thatmay connect to it.
Current now flows through pins 2 and 4 shown in RED, when the relay in energized.
Figure 22
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Relay Energized (OFF): When current stops flowing through the control circuit, pins 1 and 3, the relay
becomes de-energized.
Without the magnetic field, the switch opens and current is prevented from flowingthrough pins 2 and 4. The relay is now OFF.
Figure 23
Relay Connection: Relays are magnetized when a proper voltages and proper current is applied to it. For providing these IC ULN2803 is used. The microcontroller pins are declared as output. These pins are connected to ULN input pins. ULN outputs are then used to drive relays.
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Chapter 3. HARDWARE INTERFACING
DETAILED BLOCK DIAGRAM
Figure 24
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COMPONENTS CONTROLLED BY SENSORS
INPUTS OUTPUTS
NORP12
Light Sensor
Bulb LED Dot Matrix LCD
LM 35
Temperature SensorFan LCD
SY-HS-220
Humidity Sensor
LCD
Table 2
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Chapter 4. SOURCE CODE
#include
#include
#include#include
int main()
{
//output ports
DDRD=0xff; //LCD port
DDRB=0xff; //rows of led dot matrix
DDRC=0xff; //cols of led dot matrix
DDRA=0x06; //00000110 i.e except 1 and 2 rest all 6 are input ports
//where 1 port is for fan output
//2 port is for bulb output
//variable declarationunsigned int x,y,light,temperature,l,humidity;
while(1)
{
l1:
//initialization
LCD_init();
ADC_init();
LCD_cstm1();//pin 0 has LM 35
temperature = ADC_read(0);
temperature /= 2; //calibration
//pin 3 has SY HS 230
l = ADC_read(3);
humidity = (12*l)/80-10; //calibration
//pins 5 and 6 have norp 12
x=ADC_read(6);
y=ADC_read(5);light = (x+y)/2;//taking average
//code to display temperature on LCD
fourbit_cmd(0x80);
LCD_str("TEMPERATURE ( C)");
fourbit_cmd(0x8d);
fourbit_data(0);
fourbit_cmd(0xc8);
LCD_num(temperature);
fourbit_cmd(0xc9);
fourbit_data(0);
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fourbit_cmd(0xca);
LCD_str("C");
fourbit_cmd(0xcb);
_delay_ms(1000);
LCD_clr();
//code to display humidity on LCDfourbit_cmd(0x80);
LCD_str("HUMIDITY");
fourbit_cmd(0xc8);
LCD_num(humidity);
_delay_ms(1000);
LCD_clr();
if(light>850 && light26, switch on the fan at pin 1
if(temperature>26)//temperature
{
PORTA=0b00000010;
goto l1;
}
else
{
PORTA=0b00000000;
goto l1;
}
_delay_ms(100);
}
else if(light>450 && light26){
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PORTA=0b00000010;
goto l1;
}
else
{
PORTA=0b00000000;goto l1;
}
_delay_ms(100);
}
else if(light>350 && light26)
{
PORTA=0b00000110;
goto l1;
} //for bulb
else
{
PORTA=0b00000100;
goto l1;
}
_delay_ms(100);
}
else if(light>250 && light26)
{
PORTA=0b00000110;goto l1;
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} //for bulb
else
{
PORTA=0b00000100;
goto l1;
}_delay_ms(100);
}
}
return 0;
}
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Chapter 5. OUTPUTS CATALOGUE
1. Light Parameter Outputs1.a. Case 1
Figure 26. LCD showing SUNLIGHT
Figure 27. 2*2 display on LED DOT MATRIX
Figure 28. BULB OFF
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1.b. Case 2
Figure 29. LCD showing BRIGHT
Figure 30. 4*4 display on LED DOT MATRIX
Figure 31. BULB OFF
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1.c. Case 3
Figure 32. LCD showing DIM
Figure 33. 6*6 display on LED DOT MATRIX
Figure 34. BULB ON
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1.4. Case 4
Figure 35. LCD showing DARK
Figure 36. 8*8 display on LED DOT MATRIX
Figure 37. BULB ON
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2. Temperature Parameter Outputs
2.a. Case 1
Figure 38. LCD showing 24oC temperature
Figure 39. FAN OFF
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2.b. Case 2
Figure 40. LCD showing 28o
C temperature
Figure 41. FAN ON
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3. Humidity Parameter Outputs
3.a. Case 1
Figure 42. LCD showing 30% relative humidity
3.b. Case 2
Figure 43. LCD showing 70% relative humidity
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REFERENCES
1. Design and Implementation of Environmental Monitoring System in IntelligentSystem in Intelligent HomeHong, Wu & Wang, IEEE
2. Embedded C Programming and the Atmel AVR, Richard H Barnett3. Datasheets by i3indya Technologies4. www.atmel.in/Images/doc2466.pdf5. www.ti.com/lit/ds/symlink/lm35.pdf6. www.alldatasheet.com/datasheet-pdf/pdf/124418/ETC1/NORP-12.html7. www.alldatasheet.com/datasheet-pdf/pdf/184066/.../SY-HS-230.html8. http://embedded-lab.com/?p=24789. https://www.sparkfun.com/datasheets/LCD/ADM1602K-NSA-FBS-3.3v.pdf10.en.wikipedia.org/wiki/Relay11.http://www.labcenter.com/index.cfm
http://www.atmel.in/Images/doc2466.pdfhttp://www.ti.com/lit/ds/symlink/lm35.pdfhttp://www.alldatasheet.com/datasheet-pdf/pdf/124418/ETC1/NORP-12.htmlhttp://embedded-lab.com/?p=2478https://www.sparkfun.com/datasheets/LCD/ADM1602K-NSA-FBS-3.3v.pdfhttp://www.labcenter.com/index.cfmhttp://www.labcenter.com/index.cfmhttp://www.labcenter.com/index.cfmhttps://www.sparkfun.com/datasheets/LCD/ADM1602K-NSA-FBS-3.3v.pdfhttp://embedded-lab.com/?p=2478http://www.alldatasheet.com/datasheet-pdf/pdf/124418/ETC1/NORP-12.htmlhttp://www.ti.com/lit/ds/symlink/lm35.pdfhttp://www.atmel.in/Images/doc2466.pdf