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BRAILLE COMMUNICATOR

AN INTERNSHIP PROJECT REPORT

Submitted by

SHAIK ABDUL SAMEER (2016105065)

HARSHA VARDHAN BC (2016105535)

MANOJ KUMAR S (2016105549)

SRIRAM N (2016105594)

for the summer internship course

of

BACHELOR OF ENGINEERING

in

ELECTRONICS AND COMMUNICATION ENGINEERING

COLLEGE OF ENGINEERING GUINDY

ANNA UNIVERSITY :: CHENNAI 600 025

MAY 2018

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COLLEGE OF ENGINEERING GUINDY

ANNA UNIVERSITY :: CHENNAI 600 025

MAY 2018

INTERNSHIP CERTIFICATE

Certified that this project report “ BRAILLE COMMUNICATOR”

is the internship work of SHAIK ABDUL SAMEER

(2016105065), HARSHA VARDHAN BC (2016105535), MANOJ

KUMAR S (2016105549), SRIRAM N (2016105594) who carried out

the project work under my supervision from 7th May, 2018 to 31st May,

2018.

DR. S. MUTTAN

HEAD OF THE DEPARTMENT

Professor

ECE Department

College of Engineering Guindy

Anna University, Chennai – 25.

DR. D. SRIDHARAN

CO-ORDINATOR

Professor

ECE Department

College of Engineering Guindy

Anna University Chennai - 25

DR. N. RAMADOSS

SUPERVISOR

Associate Professor

ECE Department

College of Engineering Guindy

Anna University Chennai - 25

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ACKNOWLEDGEMENT

The final outcome of this project required a lot of guidance and assistance from

many people and we are extremely privileged to have got this all along the

completion of this project. All that we have done is only due to such supervision

and assistance and we would not forget to thank them.

We respect and thank our Dean Dr. T.V.Geetha for providing us with this

Summer Internship opportunity as it was a great learning experience for all of

us.

We respect and thank the Department of Electronics and Communication

Engineering and Dr.Muttan the HOD, Department of ECE, for providing us the

infrastructure for the completion of our internship project.

We thank Dr.D.Sridharan for coordinating us through out the internship

programme and for guiding us to optimise our project.

We owe our deep gratitude to our project guide and coordinator Dr.N.Ramadass,

who took keen interest on our project work and guided us all along, till the

completion of our project work by providing all the necessary information for

developing a good system.

Shaik Abdul Sameer

Harsha Vardhan BC

Manoj Kumar S

Sriram N

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ABSTRACT

This thesis presents a communicator that helps the visually

challenged people to communicate among others. The GSM module

used here receives the text message sent by the people to the user. The

sim card of the user is put into the sim card slot and booted up. The data

is then processed by the microcontroller (Arduino). It converts the

English alphabets into Braille language and then sends the output to the

L298 motor driver. This driver is used to drive the solenoids that

represents a single braille cell. A cell consists of six solenoids. These

solenoids are connected to two drivers. Drivers and GSM module are

powered by 12V DC adapter. Once the power is connected, the GSM

module takes 5 to 10 seconds to boot up. Then it starts to scan for any

received signal.

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TABLE OF CONTENTS

CHAPTER NO. TITLE PAGE NO.

ABSTRACT 4

TABLE OF CONTENTS

LIST OF FIGURES

1. OVERVIEW 8

1.1 Introduction 8

1.2 Objective of This Project 8

2. ARDUINO 9

2.1 Introduction 9

2.2 Features of Arduino UNO 11

2.3 Pin Description 12

3. GSM MODULE 13

3.1 Introduction 15

3.2 GSM Architecture 16

3.3 Features and specifications 18

3.3.1 Specifications 18

3.3.2 Specifications for data 18

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6. RECEIVING SMS & CONVERTING TO BRAILLE 26

6.1 Introduction 26

6.2 Interfacing SIM900A with Arduino Uno 26

6.3 Converting text to Braille 27

7. IMPLEMENTATION 28

7.1 Block diagram of Electronic setup 28

8. RESULT & CONCLUSION 29

8.1 Results 29

8.2 Accuracy 30

8.3 Conclusion 31

REFERENCES

4.

SOLENOID 20

4.1 Introduction 20

4.2 Working 21

5. L298 DRIVER 23

5.1 Introduction 23

5.2 Internal circuit diagram and applications 24

5.3 General specifications 25

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LIST OF FIGURES

Figure 2.1 Arduino Uno 10

Figure 3.1 GSM Pulse Graph 14

Figure 3.2 GSM Module 15

Figure 3.3

GSM Architecture 17

Figure 3.4

Structure of GSM Network 19

Figure 4.1 Magnetic Flux 20

Figure 4.2 Braille Cell 21

Figure 4.3 Solenoid Cell 22

Figure 5.1 L298 Driver 23

Figure 5.2 Internal Circuit Diagram of L298 24

Figure 6.1 Interfacing GSM with Arduino 26

Figure 6.2 Braille Alphabets 27

Figure 7.1 Block Diagram of Electronic Setup 28

Figure 8.1 Complete Circuit Diagram 29

Figure 8.2 Final Setup 30

Figure 8.3 Working Model 30

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CHAPTER 1

OVERVIEW

1.1 INTRODUCTION

People who are completely blind or have impaired vision usually

have a difficult time navigating outside the spaces that they're accustomed to. In

fact, physical movement is one of the biggest challenges for blind people,

explains World Access for the Blind. Also, blind people must memorize the

location of every obstacle or item in their home environment. If a blind person

lives with others, each member of the household has to be diligently about

keeping walkways clear and all items in their designated locations. Blindness

can cause significant social challenges, typically because there are activities in

which blind people can't easily participate. Frequently, blindness impacts a

person’s ability to perform many job functions, which can limit their career

options, according to the World Health Organization. This may adversely affect

their finances, and their self-esteem. Blindness may also cause difficulties when

participating in activities outside of the workplace, such as sports and

recreational activities. This can limit the blind person’s ability to socialize and

meet new people, affecting their emotional health.

1.2 OBJECTIVE OF THIS PROJECT

The objective of this project is to develop an efficient model for the

blind people to communicate. The Arduino code effectively functions and the

message is successfully translated to Braille language.

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CHAPTER 2

ARDUINO

2.1 Introduction

Arduino is an open source computer hardware and software

company, project, and user community that designs and manufactures single-

board microcontrollers and microcontroller kits for building digital devices and

interactive objects that can sense and control objects in the physical and digital

world. The project's products are distributed as open-source hardware and

software, which are licensed under the GNU Lesser General Public License

(LGPL) or the GNU General Public License (GPL), permitting the manufacture

of Arduino boards and software distribution by anyone. Arduino boards are

available commercially in preassembled form, or as do-it-yourself (DIY) kits.

Arduino board designs use a variety of microprocessors and controllers. The

boards are equipped with sets of digital and analog input/output (I/O) pins that

may be interfaced to various expansion boards or Breadboards (shields) and

other circuits. The boards feature serial communications interfaces, including

Universal Serial Bus (USB) on some models, which are also used for loading

programs from personal computers. The microcontrollers are typically

programmed using a dialect of features from the programming languages C and

C++. In addition to using traditional compiler toolchains, the Arduino project

provides an integrated development environment (IDE) based on the Processing

language project.

The Arduino project started in 2003 as a program for students at the Interaction

Design Institute Ivrea in Ivrea, Italy, aiming to provide a low-cost and easy way

for novices and professionals to create devices that interact with their

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environment using sensors and actuators. Common examples of such devices

intended for beginner hobbyists include simple robots, thermostats, and motion

detectors.

Fig. 2.1

Most Arduino boards consist of an Atmel 8-bit AVR microcontroller with

varying amounts of flash memory, pins, and features. The 32-bit Arduino Due,

based on the Atmel SAM3X8E was introduced in 2012. The boards use single

or double-row pins or female headers that facilitate connections for

programming and incorporation into other circuits. These may connect with

add-on modules termed shields. Multiple and possibly stacked shields may be

individually addressable via an I²C serial bus. Most boards include a 5 V linear

regulator and a 16 MHz crystal oscillator or ceramic resonator. Some designs,

such as the LilyPad, run at 8 MHz and dispense with the onboard voltage

regulator due to specific form-factor restrictions.

Arduino microcontrollers are pre-programmed with a boot loader that simplifies

uploading of programs to the on-chip flash memory. The default bootloader of

the Arduino UNO is the optiboot bootloader. Boards are loaded with program

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code via a serial connection to another computer. Current Arduino boards are

programmed via Universal Serial Bus (USB).

2.2 Features of the Arduino UNO

• Microcontroller: ATmega328

• Operating Voltage: 5V

• Input Voltage (recommended): 7-12V

• Input Voltage (limits): 6-20V

• Digital I/O Pins: 14 (of which 6 provide PWM output)

• Analog Input Pins: 6

• DC Current per I/O Pin: 40 mA

• Clock Speed: 16 MHz

• Flash Memory: 32 KB of which 0.5 KB used by bootloader

• SRAM: 2 KB (ATmega328)

• EEPROM: 1 KB (ATmega328)

• DC Current for 3.3V Pin: 50 mA

• An ICSP connector for bypassing the USB port

• An on-board LED attached to digital pin 13 for fast an easy

debugging of code.

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2.3 Pin Description

Pin Category Pin Name Details

Power Vin, 3.3V, 5V,

GND

Vin: Input voltage to Arduino when using an

external power source.

5V: Regulated power supply used to power

microcontroller and other components on the

board.

3.3V: 3.3V supply generated by on-board

voltage regulator. Maximum current draw is

50mA.

GND: ground pins.

Reset Reset Resets the microcontroller.

Analog Pins A0 – A5 Used to provide analog input in the range of 0-

5V

Input/output

Pins

Digital Pins 0 –

13 Can be used as input or output pins.

Serial 0(Rx), 1(Tx) Used to receive and transmit TTL serial data.

External

Interrupts 2, 3 To trigger an interrupt.

PWM 3, 5, 6, 9, 11 Provides 8-bit PWM output.

SPI

10 (SS), 11

(MOSI), 12

(MISO) and 13

(SCK)

Used for SPI communication.

Inbuilt LED 13 To turn on the inbuilt LED.

TWI A4 (SDA), A5

(SCA) Used for TWI communication.

AREF AREF To provide reference voltage for input voltage.

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CHAPTER 3

GSM MODULE (SIM900A)

3.1 Introduction

GSM (Global System for Mobile communications) is a standard

developed by the European Telecommunications Standards Institute (ETSI) to

describe the protocols for second-generation digital cellular networks used by

mobile devices such as tablets, first deployed in Finland in December 1991. As

of 2014, it has become the global standard for mobile communications – with

over 90% market share, operating in over 193 countries and territories. The

SIM900 is a complete Quad-band GSM/GPRS solution in a SMT module which

can be embedded in the customer applications. Featuring an industry-

standard interface, the SIM900 delivers GSM/GPRS 850/900/1800/1900MHz

performanceforvoice,SMS,Data, and Fax in a small form factor and with

low power consumption. SIM900 can fit almost all the space requirements in

your M2M application, especially for slim and compact demand of design.This

is a GSM/GPRS-compatible Quad-band cell phone, which can be used not only

to access the Internet, but also for oral communication (provided that it is

connected to a microphone and a small loud speaker) and for SMSs.

Externally, it looks like a big package (0.94 inches x 0.94 inches x 0.12

inches) with L-shaped contacts on four sides so that they can be soldered both on

the side and at the bottom. Internally, the module is managed by an AMR926EJ-

S processor, which controls phone communication, data communication (through

an integrated TCP/IP stack), and (through an UART and a TTL serial interface)

the communication with the circuit interfaced with the cell phone itself.

The processor is also in charge of a SIM card (3 or 1.8 V) which needs to

be attached to the outer wall of the module.In addition, the GSM900 device

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integrates an analog interface, A/D converter, RTC, SPI bus, I²C, and a PWM

module. The radio section is GSM phase 2/2+ compatible and is either class 4

(2 W) at 850/ 900 MHz or class 1 (1 W) at 1800/1900 MHz.

Fig. 3.1

The TTL serial interface is in charge not only of communicating all the

data relative to the SMS already received and those that come in during TCP/IP

sessions in GPRS (the data-rate is determined by GPRS class 10: max. 85,6 kbps),

but also of receiving the circuit commands (in our case, coming from the PIC

governing the remote control) that can be either AT standard or AT-enhanced

SIMCom type. The module is supplied with continuous energy (between 3.4 and

4.5 V) and absorbs a maximum of 0.8A during transmission.

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Fig. 3.2

3.2 GSM Architecture

A GSM network consists of the following components:

• A Mobile Station: It is the mobile phone which consists of the transceiver,

the display and the processor and is controlled by a SIM card operating over

the network.

• Base Station Subsystem: It acts as an interface between the mobile station

and the network subsystem. It consists of the Base Transceiver Station which

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contains the radio transceivers and handles the protocols for communication

with mobiles. It also consists of the Base Station Controller which controls the

Base Transceiver station and acts as a interface between the mobile station and

mobile switching centre.

• Network Subsystem: It provides the basic network connection to the mobile

stations. The basic part of the Network Subsystem is the Mobile Service

Switching Centre which provides access to different networks like ISDN,

PSTN etc. It also consists of the Home Location Register and the Visitor

Location Register which provides the call routing and roaming capabilities of

GSM. It also contains the Equipment Identity Register which maintains an

account of all the mobile equipment wherein each mobile is identified by its

own IMEI number. IMEI stands for International Mobile Equipment Identity.

A GSM modem duly interfaced to the MC through the level shifter IC

Max232. The SIM card mounted GSM modem upon receiving digit command by

SMS from any cell phone send that data to the MC through serial communication.

While the program is executed, the GSM modem receives command ‘STOP’ to

develop an output at the MC, the contact point of which are used to disable the

ignition switch. The command so sent by the user is based on an intimation

received by him through the GSM modem ‘ALERT’ a programmed message.

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Fig. 3.3

GSM networks operate in a number of different carrier frequency

ranges (separated into GSM frequency ranges for 2G and UMTS frequency

bands for 3G), with most 2G GSM networks operating in the 900 MHz or

1800 MHz bands. Where these bands were already allocated, the 850 MHz and

1900 MHz bands were used instead (for example in Canada and the United

States). In rare cases the 400 and 450 MHz frequency bands are assigned in

some countries because they were previously used for first-generation systems.

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3.3 Features and specifications

• SIM900 is designed with a very powerful single-

chip processor integrating AMR926EJ-S core

• Quad – band GSM/GPRS module with a size of 24mmx24mmx3mm

• SMT type suit for customer application

• An embedded Powerful TCP/IP protocol stack

3.3.1 Specifications:

• Quad-Band 850/ 900/ 1800/ 1900 MHz

• GPRS multi-slot class 10/8

• GPRS mobile station class B

• Compliant to GSM phase 2/2+

❖ Class 4 (2 W @850/ 900 MHz)

❖ Class 1 (1 W @ 1800/1900MHz)

• Control via AT commands (GSM 07.07 ,07.05 and SIMCOM enhanced AT

Commands)

• SIM application toolkit

• Supply voltage range 3.4 – 4.5 V

• Operation temperature: -30 °C to +80 °C

3.3.2 Specifications for data:

• GPRS class 10: max. 85.6 kbps(downlink)

• PBCCH support

• Coding schemes CS 1, 2, 3, 4

• CSD up to 14.4 kbps

• USSD

• PPP-stack

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Fig 3.4

The method chosen by GSM is a combination of Time- and

Frequency-Division Multiple Access (TDMA/FDMA). The FDMA part

involves the division by frequency of the (maximum) 25 MHz bandwidth into

124 carrier frequencies spaced 200 kHz apart. One or more carrier frequencies

are assigned to each base station. Each of these carrier frequencies is then

divided in time, using a TDMA scheme. The fundamental unit of time in this

TDMA scheme is called a burst period and it lasts 15/26 ms (or approx. 0.577

ms). Eight burst periods are grouped into a TDMA frame (120/26 ms, or

approx. 4.615 ms), which forms the basic unit for the definition of logical

channels. One physical channel is one burst period per TDMA frame.

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CHAPTER 4

SOLENOID

4.1 Introduction

A solenoid (from the French solénoïde, derived in turn from the

Greek solen ("pipe, channel") and eidos ("form, shape")) is a coil wound into a

tightly packed helix. The term was invented by French physicist André-Marie

Ampère to designate a helical coil. In physics, the term refers to a coil whose

length is substantially greater than its diameter, often wrapped around a metallic

core, which produces a uniform magnetic field in a volume of space (where

some experiment might be carried out) when an electric current is passed

through it. A solenoid is a type of electromagnet when the purpose is to

generate a controlled magnetic field. If the purpose of the solenoid is instead to

impede changes in the electric current, a solenoid can be more specifically

classified as an inductor rather than an electromagnet. Not all electromagnets

and inductors are solenoids; for example, the first electromagnet, invented in

1824, had a horseshoe rather than a cylindrical solenoid shape

Fig. 4.1

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4.2 Working

We know that the flux density vector points in the positive z direction

inside the solenoid, and in the negative z direction outside the solenoid. We

confirm this by applying the right-hand grip rule for the field around a wire. If

we wrap our right hand around a wire with the thumb pointing in the direction

of the current, the curl of the fingers shows how the field behaves. Since we are

dealing with a long solenoid, all of the components of the magnetic field not

pointing upwards cancel out by symmetry. Outside, a similar cancellation

occurs, and the field is only pointing downwards. Now consider the imaginary

loop c that is located inside the solenoid. By Ampère's law, we know that the

line integral of B (the magnetic flux density vector) around this loop is zero,

since it encloses no electrical currents (it can be also assumed that the circuital

electric field passing through the loop is constant under such conditions: a

constant or constantly changing current through the solenoid). We have shown

above that the field is pointing upwards inside the solenoid, so the horizontal

portions of loop c do not contribute anything to the integral. Thus, the integral

of the up side 1 is equal to the integral of the down side 2. Since we can

arbitrarily change the dimensions of the loop and get the same result, the only

physical explanation is that the integrands are actually equal, that is, the

magnetic field inside the solenoid is radially uniform. Note, though, that nothing

prohibits it from varying longitudinally, which in fact it does.

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Fig. 4.2

Fig. 4.3

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CHAPTER 5

L298 DRIVER

5.1 Introduction

L298N Motor Driver IC is a 15-lead high voltage, high current

Motor Driver IC with two full bridge drivers. The logic levels of L298N IC are

compatible with standard TTL and IC can be used to drive different inductive

loads like DC Motors, Stepper Motors, Relay, etc. Since the L298N Motor

Driver IC is a dual full bridge driver IC, you can control two motors at the same

time with individual inputs. The logic supply voltage is 5V but the motor supply

voltage can be as high as 45V. The peak output current per channel is 2A. The

L298N Motor Driver Module consists of two 2-pin screw terminal blocks for

connecting two motors. It also has six pin male headers for connecting the two

enable inputs and the four input pins (two for each motor).

Fig. 5.1

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5.2 Internal circuit diagram and applications

There is a 3-pin screw terminal block through which we need

to give the supply voltage to the motor. If the motors used are rated for 12V or

less, then the 12V supply is given through this screw terminal and the onboard

5V regulator will provide the 5V logic supply to the L298N IC.

Fig. 5.2

L-298 motor controller/driver has several different real-life applications, a few of

which are given below.

• Robotics.

• Weight lifters.

• CNC machines.

• Automatic door control systems.

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5.3 General specifications

• Driver: L298N

• Driver power supply: +5V~+46V

• Driver Io: 2A

• Logic power output Vss: +5~+7V (internal supply +5V)

• Logic current: 0~36mA

• Controlling level: Low -0.3V~1.5V, high: 2.3V~Vss

• Enable signal level: Low -0.3V~1.5V, high: 2.3V~Vss

• Max power: 25W (Temperature 75 Celsius)

• Working temperature: -25C~+130C

• Dimension: 60mm*54mm

• Driver weight: ~48g

• Other extensions: current probe, controlling direction indicator,

pull-up resistor switch, logic part power supply.

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CHAPTER 6

RECEIVING SMS & CONVERTING TO BRAILLE

6.1 Introduction

The text messages can be received by the SIM900A GSM

module and viewed in serial monitor of the Arduino. This is done by interfacing

the SIM900A with Arduino Uno.

6.2 Interfacing SIM900A with Arduino Uno

Fig. 6.1

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6.3 Converting text to Braille

The received text message is in the form of English

language. It has to be translated to braille language by suitable algorithm. This

is done by programming the code in the Arduino IDE. The braille language is

studied and the braille characters corresponding to English alphabets are noted.

The received text message is read and then its is decoded into single characters.

Thus, for each character the function is called and the text is converted into

braille and sent to the motor driver’s input. The motor driver correspondingly

switches the solenoids which in turn denotes the text message in braille form.

So, when the visually challenged person touches the braille cell he feels the

solenoid pop up and understands the information sent by the sender.

Fig. 6.2

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CHAPTER 7

IMPLEMENTATION

7.1 Block Diagram of Electronic setup

Fig. 7.1

The solenoids are grouped to a single solenoid cell. It is then

connected to two motor drivers. The motor driver is powered by 12V DC

supply. Six arduino pins are connected to motor drivers as inputs. The GSM

module is interfaced with arduino. Its TXD and RXD are connected to pins 9

and 10 of the arduino uno. The GSM module is powered by 12V DC supply.

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CHAPTER 8

RESULT &CONCLUSION

8.1 Results

The communicator is successfully integrated to receive the text

message and convert it into braille and display the braille characters through

solenoid cell by using Arduino Uno, SIM900A GSM module, L298 motor

driver, and solenoids.

Fig. 8.1

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Fig. 8.2 FINAL SETUP

8.2 Accuracy

Fig. 8.3

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8.2 Conclusion

The ultimate aim of this Braille communicator is to help the

visually impaired people to communicate with other persons. A buzzer is fixed

to notify the blind user that a text message is received.

REFERENCES

[1] Microprocessor Architeture, Programming and Applications with 8085 –

Ramesh S Gaonkar

[2] Microprocessor and Interfacing, Programming and Hardware – Douglas V

Hall

[3] The 8051 Microcontroller and Embedded Systems – Muhammad Ali

Mazidi

[4] https://www.elprocus.com/gsm-architecture-features-working/

[5] http://www.instructables.com/id/Interfacing-SIM900A-GSM-Modem-

with-Arduino/

[6] https://www.bc-robotics.com/tutorials/controlling-a-solenoid-valve-with-

arduino/

[7] http://www.instructables.com/id/Controlling-solenoids-with-arduino/

[8] https://create.arduino.cc/projecthub/FunguyPro/how-to-use-a-l293d-chip-

with-arduino-and-a-motor-664ff3

[9] http://www.ardumotive.com/how-to-use-the-l293d-motor-driver-ic-

en.html