AMajor Project Report on

GSM Based Water Pump Control System

Submitted to

RAJIV GANDHI TECHNICAL UNIVERSITYBHOPAL (M.P)

In Partial fulfillment for the award of degree of

BACHELOR OF ENGINEERINGIN

ELECTRONICS & COMMUNICATION

By

Anuj JainArvind VermaAsif KhanDeepak Gour

0187EC1010210187EC1010260187EC1010280187EC101035

Under the Guidance of

Mr. Nitin Muchhal(Associate Professor)

SAGAR INSTITUTE OF SCIENCE &TECHNOLOGY (SISTec)GANDHI NAGAR, BHOPAL-462036 (M.P.)

MAY-2014

SAGAR INSTITUTE OF SCIENCE AND TECHNOLOGY(Approved by AICTE Delhi, Affiliated to RGTU Bhopal and Govt. of Madhya Pradesh)

NEAR AIRPORT, GANDHI NAGAR, BHOPAL-462036

Declaration

We hereby declare that the project entitled “GSM Based Water Pump Control System”is the actual work carried out by us in the department of “Electronics and Communication” under the guidance of “Mr. Nitin Muchhal, Associate Professor”.

Name Enrollment Number Signature

Anuj Jain 0187EC101021Arvind Verma 0187EC101026Asif Khan 0187EC101028Deepak Gour 0187EC101035

SAGAR INSTITUTE OF SCIENCE AND TECHNOLOGY (Approved by AICTE Delhi, Affiliated to RGTU Bhopal and Govt. of Madhya Pradesh)

NEAR AIRPORT, GANDHI NAGAR, BHOPAL-462036

CERTIFICATE

This is to certify that the project entitled “GSM Based Water Pump Control System” has been carried out by

Anuj Jain (0187EC101021)Arvind Verma (0187EC101026)Asif Khan (0187EC101028)Deepak Gour (0187EC101035)

Under my guidance in partial fulfillment for the award of

(BACHELOR OF ENGINEERING) in (Electronics & Communication) by the Rajiv Gandhi Technical University,

Bhopal (M.P.), during the academic year 2013-14.

(Dr. Ravi Shankar Mishra)Head

Department of Electronics &Communication

(Mr. Nitin Muchhal)Project Guide

Associate Professor

(Dr. Manish Billore)Principal

ACKNOWLEDGEMENTS

It gives me a great pleasure to express my deep sense of gratitude and

indebtedness to my guide Mr. Nitin Muchhal for their valuable support and

encouraging mentally throughout the project. I am highly obliged to them for

providing me this opportunity to carry out their ideas and work during my Project

Period and helping me to gain the successful completion of my project.

My special thanks to Head of Department of Electronics & Communication

Engineering of my college, Dr. Ravi Shankar Mishra and to all of the faculties for

allowing me and encouraging me constantly to work hard in Project.

I am highly grateful to Honorable Principal of SISTec, Dr. Manish Billore, for giving

me this golden opportunity to be a part of this organization for this period.

Name Enrollment Number Signature

ANUJ JAIN 0187EC101021ARVIND VERMA 0187EC101026ASIF KHAN 0187EC101028DEEPAK GOUR 0187EC101035

INDEX

Abstract (i)

List of Table (ii)

List of figures (iii)

1. INTRODUCTION 1.1 Introduction ………………………………………………………………..1

1.2 Aims and Objectives………………………………………………………2

1.3 Working……………………………………………………………………..5

2. METHODOLOGY/EXPERIMENTATION

2.1. GSM TECHNOLOGY……………………..………………………………6

2.2. MICROCONTROLLER……………………………………………………9

2.2.1. General description ……………………...………………...…………......9

2.2.2. Pin Description…………………………………………………………...13

2.3. Max232 IC ……………………………………………………………….16

2.4. 7805 VOLTAGE REGULATOR I.C………………………………….....20

2.5. Optocoupler ……………………………………………………………...22

2.6. CRYSTAL OSCILLATOR 11.0592mhz………………………………..25

2.7. LED (Light emitting diode) …………………………………………..…26

2.8. LCD (Liquid crystal display)…………………………………………….28

2.8.1. LCD DISPLAY WITH IT PINS……………………………………….....28

2.9. ADAPTOR………………………………………………………………..30

2.10. Resister………………………………………………………………...…31

2.11. Capacitor………………………………………………………................32

2.12. Switch………………………………………………………….…………..33

2.13 Relay…................................................................................................34

2.14. RS232 Serial communication…………………………………………....36

3. SOFTWARE USED 3.1. KIEL Software…………….………………………………………………….... (38)

3.2 DIPTRACE Software………..…..……………………………………….….. (40)

4. PCB MANUFACTURING PROCESS4.1 PCB Layout….………………………………………………………………… (49)

4.2 Preparation of screen……………………………………………………….. (52)

4.3. Printing, Etching, Drilling, Green making , Tinning , component

Mounting, Etching process……………………………………………...(49)

4.4 Component Assemble………………..………………………………………(52)

4.5. Soldring Technique & Procedure…………..…………………………..…..(54)

4.6. Precaution when using C-MOS Device…………………………...………(55)

4.7. Disordering Technique……………………………………………………......(56)

4.8. . Coding………………………………………………………………………........(57)

.

5. ADVANTAGE/DISADVANTAGE ……………………………………………….(65) 6. APPLICATION……………………………………………………………………….(65)

7. CONCLUSION………………………………………………………………...……..(66)

8. DATA SHEET ……………………………………………………………………(67-69)

9. REFERENCES …………………………………………………………….…….(70)

ABSTRACT

The project aims is providing a user friendly, reliable and automated

water pumping system for irrigation. Here the automation process is done

through the wireless GSM technology and the end user need not require

any knowledge about the operation of GSM mobile. In this project

two microcontroller are used one is dedicated at the pump and other is at

the end user and two GSM modem are used for exchanging the commands.

The GSM modem present at the user end is interfaced with a few control

buttons via microcontroller, each with different functionality. Whenever a

control button is pressed it is then identified by the  microcontroller and

generates command with respect to the button pressed and forwards the

same to the water pump and the modem at the pump receives the command

and feeds the same to the microcontroller and the microcontroller perform

the required operation. The design of this system is very sensitive and

should be handled with utmost care because the  microcontroller is a 5 volt

device and is employed to monitor operation of the whole system.

List of Table

1.1 Max232 IC..........................................................................................18

1.2 Voltage Regulator…………….............................................................21

1.3 Crystal oscillator…………………………………………………….……25

1.4 LCD display char16*2………………………………………… …...…...29

1.5 Component Price List …………………………………………………...63

List of Figures1.1 Block Diagram………………………………………………………….……….. 3

1.2 Circuit Diagram………………………………………………….………………. 4

1.3 GSM MODOULE………………………………………………………….…........ 8

2.1 Microcontroller Block Diagram……………………………………….…..11

2.2 Pin configuration…………………………………………………………..12

2.3 Reset Switch…………………………………………………………….....15

3.1 MAX 232 IC Chip…………………………………………………….…….16

4.1 Voltage Regulator………………………………………………………....21

5.1 Ootocoupler………………………………………………………………...25

6.1 Crystal Oscillator…………………………………………………………...24

7.1 LED …………………………………………………………………………26

7.2 LED View…………………………………………………………………...26

8.1 LCD View ………………………………………………………………….28

9.1 Adaptor……………………………………………………………………..30

10.1 Resistor…………………………………………………………………….31

11.1 Capacitor…………………………………………………………………..32

12.1 Switch……………………………………………………………………...33

13.1 Relay View……………………………………………………………..….34

13.2 Connection……………………………………………………………..….35

13.3 Schematic & bottom view………………………………………………...35

14.1 RS232 Block Diagram…………………………………………………….37

14.2 RS232Cable……………………………………….……………….………37

15.1 KEIL Software…………………………………………………………......59

16.1 Screen………………………………………………………………………42

16.2 Component Units…………………………………………………………..43

16.3 Layout ………………………………………………………………………44

16.4 Component Top View……………………………………………………..45

17.1 Complete project…………………..……….............................................47

1.1. INTRODUCTION

This System Control the Water Pump which are place in the farm and also

send the current situation of the pump and also control the pump status on or off this

circuit take the two different power supply for control the Pump and Control unit and

also remember the timing of the pump running status.

In this system we send the information to the our Device for run in proper way for our

convince in the form of simple text format threw the Mobile in this massage we send

the time in minute as well as second and pump condition and according to this

information our device is running and also send information of its information and if

some problem accrue at the Pump Unit then it send the massage back to us and

also send the what problem are occur there.

Automated machines are man-made mechanical device that can move by

themselves, whose motion must be modeled, planned, sensed, actuated, and

controlled, and whose motion or behavior can be influenced by programming.

In the field of industrial machinery, the interaction between man and machine

typically consists of the Programming and maintaining the machine by the human

operator. This can be very easily done by using various programming languages.

The main aim of this water pump controller using GSM project is to control the

water pump by using GSM modem. In this project the mainly used components is

microcontroller in control switch another at water pump, one microcontroller send the

data then another side have to perform the corresponding functionality, here G.S.M

modems are used in this project, to communicate the both pump side and switch

side throw G.S.M the data is send to the other microcontroller. Between the water

pump and microcontroller there is interfacing circuit for the interfacing, here two

power supplies are needed to perform the operation of water pump, here use the

LED indicators to display the information.

1

The microcontroller used here operates at 5volts, this project equipment is more

sensitive because here microcontrollers used, and illiterates can easily know the

status of the motor by using LED indicator. The features of this project are easily

interfaced, high voltage water pumps are easily controlled, more sensitive, the

response is generated from the LED indicator, and wireless connection. To design

this project designer should aware of embedded c programming, PCB connections,

remote control. This project mainly used in houses.

.

1.2. Aims and Objectives:-

The GSM Based Smart Irrigation System is a project in which we get

continuous up to date status of the operation carried out in field (Farms) in the form

of SMS as well we can add other systems such as LCD displays, Webcam, Burglar

alarms, Infrared sensor and Smart Controllers suitable for the particular field.

GSM Based Automatic Irrigation System Using 8051 Micro-controller” is based on

the micro-controller unit. This electronic project provides a facility of controlling the

electrical equipments with the help of GSM modem. So I think you have understood

that I talked about GSM modem, and then the project is capable to control the

electrical equipment from any distance in the world.

Actually this project is for our farmers. They work hard and hard not only everyday

but also every night in the field. Because in the day they do their field work and in the

night our farmers have to irrigate the field land at some intervals. So to wake up in

the night from a sleep and then go to field and irrigate the land is to typical for a

farmer. There are many disadvantage of this irrigation system that if a farmer started

the irrigation system in the night and he forgot to switch off the irrigation system

again. In this condition the a lot of water goes to wastage and the crops may get

harm or sometimes he forget to switch on the irrigation system then again the crops

get dried due to lack of water. This depends on the type of crops. Lighter weight

fruits always follow slight water deficiency.

Block Diagram:

2

Fig. 1.1

Circuit diagram3

Fig. 1.2

CIRCUIT DISCRIPTION:-

4

This system controls the water pump and the various control unit. Firstly we can analysis in GSM module. In GSM module receiver signal in form of EM wave after reciving em wave signal convert in to voltage form by the antenna and then decode the msg and provide 8051 microcontroller. GSM through antenna send the information EM wave to convert logic level is differ from 8051.

Then GSM Module receiver through provide MAX232 IC. And it is convert 8051 logic level. This signal is understand by microcontroller that the msg is pump on or pump of, and it is connected on pin no. 21. Then the MAX232 IC is description is pin 1-3 connected to the capacitor(104) ,and pin 4-5 to the connected capacitor(104), pin no. 6 & ground is capa(104), then pin 16 is Vcc and 15 is connected to Ground. Pin no. 14 & 13 is connected to the GSM module, and pin no. 11 & 12 are connected to the controller (pin 11 is connected to 11, and 12 is connected to pin no. 10).

In microcontroller pin no. 21 is connected to the forward opto-coupler relay unit and pin no. 22 is work on reverse to opto- coupler relay unit. Opto-coupler is EL 817; it is isolation between relay unit and controller unit. It is used for safe the complete controller circuit and safe to electrical shock.

Inside in opto-coupler having LED & photo diode pair. Then send the msg in LCD to display the msg so we can use the one serial resister bank , resister bank is eight resister are connected to the between the controller and LCD. Pin no. 26, 27, and 28, are controller are connected to the LCD. Pin no. 32 to 39 is data pin and it is connected to the LCD in pin no. 7 to 14. So finally we can show the MSG in display through LCD.

5

1.3. WORKING:- The power supply needed by the controlling system is +5V.Fig-1 Block

diagram for proposed System components the connections between the two mobiles

are done using GSM. The GSM module and microcontroller are connected using

MAX232. The microcontroller then gives a signal to the called mobile (which is kept

in the auto answering mode).

SMS/GSM Remote Water Pump Controller is a device which can control and

monitor electric motors, agriculture pump sets through mobile phone. This is a GSM

based remote controller to switch ON and OFF pump sets or any electric motor from

remote location. This SMS/GSM remote controller helps the farmer to handle

agricultural pump sets easily. Farmer can set running time of pump set after it gets

ON. It also helps the farmers to save life from snake bite in night time, saves water,

time and electricity. The microcontroller used here operates at 5volts, this project

equipment is more sensitive because here microcontrollers used, and illiterates can

easily know the status of the motor by using LED indicator. The features of this

project are easily interfaced, high voltage water pumps are easily controlled, more

sensitive, the response is generated from the LED indicator, and wireless

connection. To design this project designer should aware of embedded c

programming, PCB connections, remote control. This project mainly used in houses.

In this condition the a lot of water goes to wastage and the crops may get harm or

sometimes he forget to switch on the irrigation system then again the crops get dried

due to lack of water. Another way to benefit from this feature is to keep the same

performance by reducing the clock frequency by half, thus dramatically reducing the

EMI. Subscriber Identity Module (SIM) cards, which allow customers to buy a new or

additional phone, or a GSM PC Card modem, and instantly transfer their settings,

preferences and contacts to the other device. If SMS is sent ON then RLY 1will Go

On for 5 Sec Then Start Button will be pressed Pump will go On ( Circuit Closed ). If

SMS is sent OFF Then RLY2 Will Go On for 5 Sec Then NC will be Open Pump Will

Go Off(Circuit Open).

6

GSM MODULE2.1. GSM Technology:-

More than 6 billion people worldwide use the Global System for Mobile

Communications (GSM) family of technologies. GSM is the most widely used

wireless technology in the world, available in more than 219 countries and territories

worldwide, with a market share of more than 90 percent.

GSM market share has grown exponentially over recent years. Although it took 12

years for GSM to achieve 1 billion customers (February 2004), it was only another

2.5 years before GSM subscribers passed the 2 billion mark (June 2006), less than

two years to exceed 3 billion customers (April 2008) and reached more than 6 billion

in 2012.

GSM is the legacy network of the evolution to the third generation (3G) technologies

Universal Mobile Telecommunication System (UMTS), also known as WCDMA, and

High Speed Packet Access (HSPA). Commonly referred to as the GSM family of

technologies, the following diagram represents the evolution from second generation

(2G) GSM and General Packet Radio System (GPRS) to 3G Enhanced Data for

GSM Evolution (EDGE), UMTS and HSPA.

There are several reasons why GSM is so popular among operators and their

customers:

Clear voice quality, which helps make GSM a viable alternative to wireline

telephony for consumers and businesses.

International roaming with service available in more than 219 countries, the

most of any wireless technology by a wide margin. As a result, users enjoy

the convenience of being reachable with their GSM devices and phone

numbers when traveling abroad, as well as the ability to access messaging

7

and other advanced services that they use in their home markets.

Partnerships within the GSM community help to keep users' roaming charges

affordable and allow for any roaming charges to be automatically billed to their

accounts back in their home markets. Roaming is particularly important for

operators for two reasons: first, it drives a significant amount of revenue; and

second, roaming support helps operators attract enterprise customers.

Spectral flexibility, with network infrastructure and user devices available for

numerous spectrum bands. Tri- and quad-band GSM phones are common,

reducing the chances that users will ever travel to an area without at least one

GSM network to which they can connect.

Tight security, including inherent protection from eavesdropping and

hacking. This helps make GSM voice and data an attractive alternative to

analog cellular and Wi-Fi in the eyes of users, particularly enterprises.

Data support, including SMS and web browsing.

Subscriber Identity Module (SIM) cards, which allow customers to buy a

new or additional phone, or a GSM PC Card modem, and instantly transfer

their settings, preferences and contacts to the other device.

Product selection. The GSM family’s 90 percent worldwide market share

makes it a popular choice for handset manufacturers and application

developers. As a result, GSM customers enjoy the largest selection of

handsets, PC card modems and other devices, as well as innovative voice

and data services. The GSM family’s market share also translates into large

volumes of network infrastructure and user devices, which drive down costs.

For operators, those savings mean that with GSM, they can price their

devices and services more competitively than with any other wireless

technology. GSM's market share also attracts vendors and application

developers, whose innovative content, services and devices help operators

attract and retain customers.

8

GSM MODULE:-

Fig 1.3

9

2.2. MICROCONTROLLER (P89V51RD2BN)

2.2.1. General description:

The P89V51RD2 are 80C51 microcontrollers with 16kB Flash and 1024 bytes

of data RAM. A key feature of the P89V51RD2 is its X2 mode option. The design

engineer can choose to run the application with the conventional 80C51 clock rate

(12 clocks per machine cycle) or select the X2 mode (6 clocks per machine cycle) to

achieve twice the throughput at the same clock frequency. Another way to benefit

from this feature is to keep the same performance by reducing the clock frequency

by half, thus dramatically reducing the EMI.

The Flash program memory supports both parallel programming and in serial In-

System Programming (ISP). Parallel programming mode offers gang-programming

at high speed, reducing programming costs and time to market. ISP allows a device

to be reprogrammed in the end product under software control. The capability to

field/update the application firmware makes a wide range of applications possible.

The P89V51RD2 is also In-Application Programmable (IAP), allowing the Flash

program memory to be reconfigured even while the application is running.

Features

80C51 Central Processing Unit

• 5V Operating voltage from 0 MHz to 40 MHz

• 16/32/64 kB of on-chip Flash user code memory with ISP and IAP Supports 12-

clock (default) or 6-clock mode selection via software

• SPI (Serial Peripheral Interface) and enhanced UART

• PCA (Programmable Counter Array) with PWM and Capture/Four 8-bit I/O ports

with three high-current Port 1 pins (16Three 16-bit timers/counters

• Programmable watchdog timer

10

• Eight interrupt sources with four priority levels

• Second DPTR register

• Low EMI mode (ALE inhibit)

• TTL- and CMOS-compatible logic levels

• Brown-out detection

• Low power modes - Power-down mode with external interrupt wake-up - Idle mode

• DIP40, PLCC44 and TQFP44 packages

11

Block diagram:

Fig 2.1

12

Pin Configuration:

Figure 2.2

13

2.2.2 PIN DISCRIPTION:-

PIN 1–8: PORT 1: (P1.0 to P1.7):

Port 1 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 1 pins are

pulled high by the internal pull-ups when ‘1’s are written to them and can be used as

inputs in this state. As inputs, Port 1 pins that are externally pulled LOW will source

current (IIL) because of the internal pull-ups. P1.5, P1.6, P1.7 have high current

drive of 16 mA. Port 1 also receives the low-order address bytes during the external

host mode programming and verification. P1.0: T2: External count input to

Timer/Counter 2 or Clock-out from Timer/Counter 2 P1.1: T2EX: Timer/Counter 2

capture/reload trigger and direction control P1.2: ECI: External clock input. This

signal is the external clock input for the PCA. P1.3: CEX0: Capture/compare external

I/O for PCA Module 0. Each capture/compare module connects to a Port 1 pin for

external I/O. When not used by the PCA, this pin can handle standard I/O. P1.4: SS:

Slave port select input for SPI. CEX1: Capture/compare external I/O for PCA Module

1 P1.5: MOSI: Master Output Slave Input for SPI CEX2: Capture/compare external

I/O for PCA Module 2 P1.6: MISO: Master Input Slave Output for SPI CEX3:

Capture/compare external I/O for PCA Module 3 P1.7: SCK: Master Output Slave

Input for SPI CEX4: Capture/compare external I/O for PCA Module 4

PIN 9: RESET SIGNAL:High logical state on this input halts the MCU and clears all the registers. Bringing

this pin back to logical state zero starts the program a new as if the power had just

been turned on. In another words, positive voltage impulse on this pin resets the

MCU. Depending on the device's purpose and environs, this pin is usually connected

to the push-button, reset-upon-start circuit or a brown out reset circuit (covered in the

previous chapter). The image shows one simple circuit for safe reset upon starting

the controller. It is utilized in situations when power fails to reach its optimal voltage.

Fig 2.3 RESET SWITCH

14

10-17: PIN Port 3:

Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3 pins are pulled

HIGH by the internal pull-ups when ‘1’s are written to them and can be used as

inputs in this state. As inputs, Port 3 pins that are externally pulled LOW will source

current (IIL) because of the internal pull-ups. Port3 also receives some control

signals and a partial of high-order address bits during the external host mode

programming and verification. P3.0: RXD: serial input port P3.1: TXD: serial output

port P3.2: INT0: external interrupt 0 input P3.3: INT1: external interrupt 1 input P3.4:

T0: external count input to Timer/Counter 0 P3.5: T1: external count input to

Timer/Counter 1 P3.6: WR: external data memory write strobe P3.7: RD: external

data memory read strobe PIN 18: XTAL2: Crystal 2: Output from the inverting

oscillator amplifier. PIN 19: XTAL1: Crystal 1: Input to the inverting oscillator

amplifier and input to the internal clock generator circuits.

PIN 20: Ground

PIN 21-28: (P2.0 toP2.7):

Port 2: Port 2 is an 8-bit bi-directional I/O port with internal pull-ups. Port 2 pins are

pulled HIGH by the internal pull-ups when ‘1’s are written to them and can be used

as inputs in this state. As inputs, Port 2 pins that are externally pulled LOW will

source current (IIL) because of the internal pull-ups. Port 2 sends the high-order

address byte during fetches from external program memory and during accesses to

external Data Memory that use 16-bit address (MOVX@DPTR). In this application, it

uses strong internal pull-ups when transitioning to ‘1’s. Port 2 also receives some

control signals and a partial of high-order address bits during the external host mode

programming and verification. PIN 29: Program Store Enable: PSEN is the read

strobe for external program memory. When the device is executing from internal

program memory, PSEN is inactive (HIGH). When the device is executing code from

external program memory, PSEN is activated twice each machine cycle, except that

two PSEN activations are skipped during each access to external data memory. A

forced HIGH-to-LOW input transition on the PSEN pin while the RST input is

continually held HIGH for more than 10 machine cycles will cause the device to enter

external host mode programming. PIN 30: Address Latch Enable: ALE is the output

15

signal for latching the low byte of the address during an access to external memory.

This pin is also the programming pulse input (PROG) for flash programming.

Normally the ALE [1] is emitted at a constant rate of 16 the crystal frequency and can

be used for external timing and clocking. One ALE pulse is skipped during each

access to external data memory. However, if AO is set to ‘1’, ALE is disabled.

PIN 31: External Access Enable: EA must be connected to VSS in order to enable

the device to fetch code from the external program memory. EA must be strapped to

VDD for internal program execution. However, Security lock level 4 will disable EA,

and program execution is only possible from internal program memory. The EA pin

can tolerate a high voltage of 12 V. PIN 32 TO 39: P0.0 – P0.7: Port 0: Port 0 is an

8-bit open drain bi-directional I/O port. Port 0 pins that have ‘1’s written to them float,

and in this state can be used as high- impedance inputs. Port 0 is also the

multiplexed low-order address and data bus during accesses to external code and

data memory. In this application, it uses strong internal pull- ups when transitioning

to ‘1’s. Port 0 also receives the code bytes during the external host mode

programming, and outputs the code bytes during the external host mode verification.

External pull-ups are required during program verification or as a general purpose

I/O port.

PIN 40: VDD: Power supply

16

2.3. MAX232

Fig.3.1

The MAX232 is an IC, first created in 1987 by Maxim Integrated Products, that

converts signals from an RS-232 serial port to signals suitable for use in TTL

compatible digital logic circuits. The MAX232 is a dual driver/receiver and typically

converts the RX, TX, CTS and RTS signals.

The drivers provide RS-232 voltage level outputs (approx. ± 7.5 V) from a single

+ 5 V supply via on-chip charge pumps and external capacitors. This makes it useful

for implementing RS-232 in devices that otherwise do not need any voltages outside

the 0 V to + 5 V range, as power supply design does not need to be made more

complicated just for driving the RS-232 in this case.

The receivers reduce RS-232 inputs (which may be as high as ± 25 V), to standard

5 V TTL levels. These receivers have a typical threshold of 1.3 V, and a typical

hysteresis of 0.5 V.

17

Contents 1 Versions

2 Voltage levels

3 Applications

VersionsThe later MAX232A is backwards compatible with the original MAX232 but may

operate at higher baud rates and can use smaller external capacitors – 0.1 μF in

place of the 1.0 μF capacitors used with the original device. The newer MAX3232 is

also backwards compatible, but operates at a broader voltage range; from 3 to 5.5 V.

in-to-pin compatible versions from other manufacturers are ICL232, ST232, ADM232

and HIN232.

Voltage levels

It is helpful to understand what occurs to the voltage levels. When a MAX232 IC

receives a TTL level to convert, it changes TTL logic 0 to between +3 and +15 V,

and changes TTL logic 1 to between -3 to -15 V, and vice versa for converting from

RS232 to TTL. This can be confusing when you realize that the RS232 data

transmission voltages at a certain logic state are opposite from the RS232 control

line voltages at the same logic state. To clarify the matter, see the table below. For

more information, see RS-232 voltage levels.

18

TABLE:-

RS232 line type and logic levelRS232 voltage

TTL voltage to/from MAX232

Data transmission (Rx/Tx) logic 0 +3 V to +15 V 0 V

Data transmission (Rx/Tx) logic 1 -3 V to -15 V 5 V

Control signals (RTS/CTS/DTR/DSR)

logic 0-3 V to -15 V 5 V

Control signals (RTS/CTS/DTR/DSR)

logic 1+3 V to +15 V 0 V

Table 1.1

19

Applications

RS-232 to TTL converters, using MAX232

The MAX232 (A) has two receivers (converts from RS-232 to TTL voltage levels),

and two drivers (converts from TTL logic to RS-232 voltage levels). This means only

two of the RS-232 signals can be converted in each direction. Typically, a pair of a

driver/receiver of the MAX232 is used for TX and RX signals, and the second one for

CTS and RTS signals.

There are not enough drivers/receivers in the MAX232 to also connect the DTR,

DSR, and DCD signals. Usually these signals can be omitted when e.g.

communicating with a PC's serial interface. If the DTE really requires these signals,

either a second MAX232 is needed, or some other IC from the MAX232 family can

be used. Also, it is possible to directly wire DTR (DB9 pin #4) to DSR (DB9 pin #6)

without going through any circuitry. This gives automatic (brain dead) DSR

acknowledgment of an incoming DTR signal.

20

2.4. Voltage Regulator:

A voltage regulator is an electrical regulating device that is made to automatically

sustain a constant level of voltage or to put a cap on how much voltage can pass

through.

7805 is a voltage regulator integrated circuit. It is a member of 78xx series of fixed

linear voltage regulator ICs. The voltage source in a circuit may have fluctuations

and would not give the fixed voltage output. The voltage regulator IC maintains the

output voltage at a constant value. The xx in 78xx indicates the fixed output voltage it

is designed to provide. 7805 provides +5V regulated power supply. Capacitors of

suitable values can be connected at input and output pins depending upon the

respective voltage levels. 78xx ICs have three terminals and are commonly found in

the TO220 form factor, although smaller surface-mount and larger TO3 packages

are available. These devices support an input voltage anywhere from a couple of

volts over the intended output voltage, up to a maximum of 35 to 40 volts depending

on the make, and typically provide 1 or 1.5 amperes of current (though smaller or

larger packages may have a lower or higher current rating).

21

Pin Diagram of voltage Regulator:-

Fig 4.1

Pin Description:

Pin No Function Name

1 Input voltage (5V-18V) Input

2 Ground (0V) Ground

3 Regulated output; 5V (4.8V-5.2V) Output

Table 1.2

2.5. Opto-coupler:-

22

An opto-isolator contains a source (emitter) of light, almost always a near infrared

light-emitting diode (LED), that converts electrical input signal into light, a closed

optical channel (also called dialectical channel), and a photo sensor, which detects

incoming light and either generates electric energy directly, or modulates electric

current flowing from an external power supply.opto-isolator can transfer the light

signal not transfer the electrical signal . The sensor can be a photo resistor, a

photodiode, a phototransistor, a silicon-controlled rectifier (SCR) or a triac. Because

LEDs can sense light in addition to emitting it, construction of symmetrical,

bidirectional opto-isolators is possible. An opto coupled solid state relay contains a

photodiode opto-isolator which drives a power switch, usually a complementary pair

of MOSFETs. A slotted optical switch contains a source of light and a sensor, but its

optical channel is open, allowing modulation of light by external objects obstructing

the path of light or reflecting light into the sensor.

Optocoupler view:

23

Fig. 5.1

2.6. Crystal Oscillator Frequency:

Crystal oscillators can be manufactured for oscillation over a wide range of

frequencies, from a few kilohertz up to several hundred megahertz. Many

applications call for a crystal oscillator frequency conveniently related to some other

desired frequency, so hundreds of standard crystal frequencies are made in large

quantities and stocked by electronics distributors. Using frequency dividers,

frequency multipliers and phase locked loop circuits it is practical to derive a wide

range of frequencies from one reference frequency.

Crystal Oscillator view:

24

Fig.6.1

Frequency comm. UART A/VRTC Primary uses

25

(MHz)

0.032000 XReal-time clocks, stop watches; allows binary

division to 1 kHz signal (25×1 kHz).

0.032768 X

Real-time clocks, quartz watches and clocks;

allows binary division to 1 Hz signal (215×1 Hz);

also low-speed low-power microcontrollers. Very

common.

0.038000Used with FM encoder chip BA1404 and similar,

also seen in DMM's

0.077500 XReal-time clocks, quartz watches and clocks; also

the DCF77 frequency

0.100000 XReal-time clocks, quartz watches and clocks, DMM

dual slope ADC's(suppresses 50Hz noise)

0.120000 X DMM dual slope ADC's (suppresses 60Hz noise)

0.131072 X Found in Fluke 17/19 DMM's

1.000000

Reference frequency. Common standard

frequency. Harmonics fall on integer MHz

frequencies.

1.008 9600

UART clock; allows integer division to common

baud rates, used for 1200 and 2400 baud

modems.

(30 * 33600 baud, 105 * 9600 baud, 840 *

1200 baud)

1.544Bit clock for DS1 systems (+-32 ppm, ANSI

T1.102).

1.8432 115200 UART clock allows integer division to common.

Table 1.3

26

2.7. LED:

LED's are special diodes that emit light when connected in a circuit. They are frequently

used as "pilot" lights in electronic appliances to indicate whether the circuit is closed or not.

A clear (or often colored) epoxy case enclosed the heart of an LED, the semi-conductor chip.

LED VIEW:-

Fig.7.1

Fig.7.2

27

The two wires extending below the LED epoxy enclosure or the "bulb" indicate how

the LED should be connected into a circuit. The negative side of an LED lead is

indicated in two ways: 1) by the flat side of the bulb, and 2) by the shorter of the two

wires extending from the LED. The negative lead should be connected to the

negative terminal of a battery. LED's operate at relative low voltages between about

1 and 4 volts, and draw currents between about 10 and 40 mill amperes. Voltages

and currents substantially above these values can melt a LED chip.

The most important part of a light emitting diode (LED) is the semi-conductor chip

located in the center of the bulb as shown at the right. The chip has two regions

separated by a junction. The p region is dominated by positive electric charges,

The n region is dominated by negative electric charges. The junction acts as a

barrier to the flow of electrons between the p and the n regions. Only when sufficient

voltage is applied to the semi-conductor chip, can the current flow and the electrons

cross the junction into the p region.

In the absence of a large enough electric potential difference (voltage) across the

LED leads, the junction presents an electric potential barrier to the flow of electrons.

28

2.8. LCD (Liquid crystal display)

LCD (Liquid Crystal Display) screen is an electronic display module and find a

wide range of applications. A 16x2 LCD display is very basic module and is very

commonly used in various devices and circuits. These modules are preferred

over seven segments and other multi segment LEDs. The reasons being: LCDs

are economical; easily programmable; have no limitation of displaying special &

even custom characters (unlike in seven segments), animations and so on.

A 16x2 LCD means it can display 16 characters per line and there are 2 such

lines. In this LCD each character is displayed in 5x7 pixel matrix. This LCD has

two registers, namely, Command and Data.

The command register stores the command instructions given to the LCD .A

command is an instruction given to LCD to do a predefined task like initializing

it, clearing its screen, setting the cursor position, controlling display etc. The

data register stores the data to be displayed on the LCD. The data is the ASCII

value of the character to be displayed on the LCD. Click to learn more about

internal structure of a LCD

29

Fig. 8.12.8.1. TABLE LCD DISPLAY WITH IT PINS

 Pin

No Function  Name

1 Ground (0V) Ground

2 Supply voltage; 5V (4.7V – 5.3V)  Vcc

3 Contrast adjustment; through a variable

resistor

 VEE

4 Selects command register when low; and

data register when high

Register

Select

5 Low to write to the register; High to read from

the register

Read/

write

6 Sends data to data pins when a high to low

pulse is given

Enable

7

8-bit data pins

DB0

8 DB1

9 DB2

10 DB3

11 DB4

12 DB5

13 DB6

14 DB7

15 Backlight VCC (5V) Led+

16 Backlight Ground (0V) Led-

Table 1.4

30

2.9. ADAPTOR An adapter or adaptor [1] is a device that converts attributes of one device

or system to those of an otherwise incompatible device or system. The term is

often used to refer to AC adapters .An electrical adapter may enable connection

of a socket used in one region to a plug used in another by offering connections

for the disparate contact arrangements, while not changing the voltage. For

more, see: AC power plugs and sockets.

A garden hose adapter can convert between threads and quick-release, "snap"-

type connections .One kind of serial port adapter enables connections between

25-contact and nine-contact connectors, but does not affect electrical power-

and signal-related attributes.

FIG.9.1

31

Convert the interface of a class into another interface clients expect. Adapter

lets classes work together that couldn't otherwise because of incompatible

interfaces. Wrap an existing class with a new interface .Impedance match an

old component to a new system The Adapter could also be thought of as a

"wrapper"

2.10.RESISTOR A Resistor is a two-terminal electrical or electronic component that opposes an

electric current by producing a voltage drop between its terminals in accordance with

Ohm's law: The electrical resistance is equal to the voltagedrop across the resistor

divided by the current through the resistor. Resistors are used as part of electrical

networks and electronic circuits.

Fig. 10.1

32

2.11.CAPACITOR:-

Fig.11.1

Capacitors: SMD ceramic at top left; SMD tantalum at bottom left; through-hole

tantalum at top right; through-hole electrolytic at bottom right. Major scale divisions

are cm.

A capacitor is an electrical/electronic device that can store energy in the electric field

between a pair of conductors (called "plates"). The process of storing energy in the

capacitor is known as "charging", and involves electric charges of equal magnitude,

but opposite polarity, building up on each plate.

Capacitors are often used in electrical circuit and electronic circuits as energy-

storage devices. They can also be used to differentiate between high-frequency and

low-frequency signals. This property makes them useful in electronic filters.

33

Capacitors are occasionally referred to as condensers. This is considered an

antiquated term in English, but most other languages use an equivalent, like

"Condensate" in German.

2.12.Switch The most familiar form of switch is a manually operated electromechanical

device with one or more sets of electrical contacts, which are connected to external

circuits. Each set of contacts can be in one of two states: either "closed" meaning the

contacts are touching and electricity can flow between them, or "open", meaning the

contacts are separated and the switch is no conducting. The mechanism actuating

the transition between these two states (open or closed) can be either a "toggle" (flip

switch for continuous "on" or "off") or "momentary" (push-for "on" or push-for "off")

type.

FIG.12.1

34

2.13. RELAY

Introduction:

A relay is an electrical switch that opens and closes under control of another

electrical circuit. In the original form, the switch is operated by an electromagnet to

open or close one or many sets of contacts. It was invented by Joseph Henry in

1835. Because a relay is able to control an output circuit of higher power than the

input circuit, it can be considered, in a broad sense, to be a form of an electrical

amplifier.

Relay 12VDC

FIG. 13.1

35

Connection:

FIG.13.2

Schematic:

RELAY BOTTOM VIEW:

36

FIG.13.3

2.14. SERIAL COMMUNICATION

In order to connect micro controller or a PC to any modem a serial port is

used. Serial, is a very common protocol for device communication that is standard

on almost every PC .Most computers including RS-232 based serial ports. Serial is

also a common communication protocol that is used by many devices for

instrumentation.

In serial communication, the data is sent one bit at a time in contrast parallel

communication, in which the data is sent a byte or more at time. Serial

communication uses a single data line where as the parallel communication uses 8

bit data line , this makes serial communication not only inexpensive but also makes

it possible for two computers located in two different cities to communicate over the

telephone.

Serial data communication uses two methods, asynchronous and synchronous. the

synchronous method transfers a block of data at a time while the asynchronous

transfers a single byte at a time. The 8051 have an in built UART (Universal

Asynchronous Receiver- Transmitter).

Typically, serial is used to transmit ASCII data. Communication is completed using 3

transmission lines: (1) Transmitter, (2) Receiver and (3) Ground. Since serial is

asynchronous, the port is able to transmit data on one line while receiving data on

another. Other lines are available for handshaking, but are not required. The

37

important characteristics are Data Transfer Rate, Start and Stop bits, Data bits and

Parity bits. For two ports to communicate, these parameters must match.

Serial communication transmission method

BLOCK DIAGRAM RS232

Fig.14.1

RS232 CABLE

38

Fig.14.2

3. SOFTWARES USED:

3.1. KEILS SOFTWARE:The simulator/ debugger in KEIL can perform a very detailed simulation of a micro

controller along with external signals. It is possible to view the precise execution time

of a single assembly instruction, or a single line of C code, all the way up to the

entire application, simply by entering the crystal frequency. A window can be opened

for each peripheral on the device, showing the state of the peripheral. This enables

quick trouble shooting of miss-configured peripherals. Breakpoints may be set on

either assembly instructions or lines of C code, and execution may be stepped

through one instruction or C line at a time. The contents of all the memory areas may

be viewed along with ability to find specific variables. In addition the registers may be

viewed allowing a detailed view of what the microcontroller is doing at any point in

time.

The Kiel Software 8051 development tools listed below are the programs you use to

compile your C code, assemble your assembler source files, link your program

together, create HEX files, and debug your target program. µVision2 for Windows

Integrated Development Environment: combines Project Management, Source Code

Editing, and Program Debugging in one powerful environment.

39

C51 ANSI Optimizing C Cross Compiler: creates reloadable object modules from

your C source code, A51 Macro Assembler: creates reloadable object

modules from your 8051 assembler source code, BL51 Linker/Locator:

combines reloadable object modules created by the compiler and assembler into the

final absolute object module, LIB51 Library Manager: combines object modules into

a library, which may be used by the linker, OH51 Object-HEX Converter: creates

Intel HEX files from absolute object modules.

EVALUTATION OF KEIL SOFTWARE:

1. Start the UVision program;

40

Fig.15.1

3.2. DIP TRACE:

Dip trace software is used to design our circuitry on PCB so that it can be printed

and apart from breadboard we have very less probability of errors. So complete

designing is done in software and then implemented on PCB and then drilling and

soldering process takes place. Cover areas such as the size and shape of your PCB

layout, which components are used as well as more advanced features such as

automatic routing and component placement. For many circuits you can leave the

settings in the window unchanged. With your transistor sensing circuit, just one

option will be changed. You will change a setting to increase the thickness of the

copper tracks that will be added during the automatic routing process. By increasing

the thickness of the tracks, you will make your finished PCB layout easier to build.

Note that with more complex circuits, particularly circuits involving integrated circuits

(ICs), thinner tracks are normally required to allow the circuit to be routed

successfully.

Step 1:-How to design and make an electronic circuit with DIP TRACE. You should follow

this tutorial to learn the basic skills you will need to use DIP TRACE effectively.

41

You will create a transistor sensing circuit similar to the one shown on the right. The

circuit will light an LED when the temperature gets too cold. Along the way, you will

learn how to: Add components from the Gallery Wire components together

Change component values and models convert the circuit into a PCB layout View

how the finished PCB will look

You will begin by creating a new (empty) document in which to draw your circuit. To

create a new document, click on the new button or choose New from the File menu.

Next you will learn how to use the Gallery to add components to your circuit. If the

Gallery is not currently open, click on the Gallery button on the top toolbar to open it.

Select the CircuitSymbols option. In the Circuit Symbol Gallery window, you will be able to see all the

components that are available within PCB Wizard.

Step 2:-Adding componentsFrom the Power Supplies group, add a Battery component from the Gallery to your

circuit.

To do this:

Move the mouse over the Battery symbol. Press and hold down the left mouse

button. With the left mouse button still held down, move the mouse to drag the

symbol onto the circuit. Finally, release the mouse button when the circuit symbol is

in the required position. Components within the Gallery are grouped according to

their function. At the top of the window, a drop-down list box allows you to select

which group is shown.

Once the components have been placed, you can start to wire the

Components together. To do this you must first click on the Select

Button from the top toolbar:

Next, move the mouse over the top pin of the battery (a). As you hold the mouse

over the pin you will notice a hint appear?

Describing that particular component pin. Press and hold down the left mouse

button. With the mouse button still held

42

Down, move the mouse to place a wire. You can add a bend to the wire by releasing

the mouse button over or

Clicking on an empty part of the circuit .To complete the wire, release the mouse

button over the top pin of resistor

43

44

SCREEN:-

Fig 16.1

COMPONENT UNITS:

Fig.16.2

LAYOUT:

Fig.16.3

COMPONENT TOP VIEW:-

Fig. 16.4

Now that the transistor sensing circuit is complete, you can convert it into a printed

circuit board. For more information on the options available for converting your circuit

diagrams into PCB layouts, see the topic entitled Converting to a PCB layout in the

Help. From the Tools menu choose Convert | Design to Printed Circuit Board.

You will see a window appear to lead you through the conversion process. The

window contains a series of pages that allow you to decide how your circuit is

converted.

These pages cover areas such as the size and shape of your PCB layout, which

components are used as well as more advanced features such as automatic routing

and component placement. For many circuits you can leave the settings in the

window unchanged. With your transistor sensing circuit, just one option will be

changed. You will change a setting to increase the thickness of the copper tracks

that will be added during the automatic routing process. By increasing the thickness

of the tracks, you will make your finished PCB layout easier to build. Note that with

more complex circuits, particularly circuits involving integrated circuits (ICs), thinner

tracks are normally required to allow the circuit to be routed successfully.

Complete Project View:

Fig.17.1

Steps Of Project Making

The following steps have been followed in carrying out the project:-1. Understand the working of the circuit.

2. Prepare the circuit diagram.

3. Prepare the list to components along with their specification estimate the

contend procure them after carrying out market survey.

4. Plan and prepare PCB for mounting all the components.

5. Fix the components on the PCB and solder them.

6. Test the circuit for the desired performance.

7. Give good finish to the unit.

8. Prepare the project report

4. PCB MANUFACTURING PROCESS

4.1. PCB LAYOUT

Lay out of the desired circuit is the most important in any circuit board manufacturing

process. The following points are to be observed while performing the layout of the

PCB. Sufficient space should be maintained between two components. High heat

dissipation components like high voltage resistors should be mounted at a sufficient

distance from the semiconductors and electrolytic capacitors. Components layout

should make proper combination with copper side circuit layout. Circuit copper line

thickness should be decided taking into account the current drain in the circuit.

4.2. PREPARATION OF SCREEN

Nylon bolting cloth (Silk screen cloth) is stretched and attached to a wooden frame.

Photosensitive chemical (silcot-6) and ammonium bicarbonate is spread on cloth and

dried in total darkness. The screen is exposed to UV light and is developed in water.

4.3. PRINTING:

The screen is placed on suitable copper laminated sheet on copper side and circuit

black printing ink (acid resistant paint) is spread on it. After printing, the PCB should

be allowed to dry for at least 10 hrs. In a dust proof chamber.

ETCHING :

The removal of excess copper on the copper laminated PCB apart from the printed

circuit is known as Etching. Generally PCB is placed in FeCl3 solution and kept for

one hour.

DRILLING :

Under this operation drilling should be done as per circuit layout with the suitable drill

and high speed machine. Drilling should always be done from copper side to avoid

possibility of coming out of copper circuit and chipping out of Bakelite.

GREEN MAKING :

Cleaning the screen. It provides as better and also prevents frequency overlapping

between the tacks at high frequency operation.

It is done with special epoxy paint and special thinner is required for.

TINNING :

It is an electroplating process (tin plating) done to increases the conductivity of the

conducting medium and to avoid oxidizing effect.

COMPONENT MOUNTING :

All components are mounted at their respective position as per the components

layout. Proper precautions should be taken during mounting process.

ETCHING PROCESS :

Etching process requires the use of chemicals, acid resistant dishes and running

water supply. Ferric chloride is maximum used solution but other enchants such as

ammonium per sulfate can be used. Nitric acid can be used but in general it is not

used due to poisonous fumes. The pattern prepared is glued to the copper surface of

the board using a latex type of adhesive that can be cubed after use. The pattern is

laid firmly on the copper use a very sharp knife to cut round the pattern carefully a

remove the paper corresponding to the required copper pattern areas. Then apply

the resist solutions, which can be kind of ink proportion fort the purpose maintaining

smoothing clean outlines as far as possible. While the board is drying test all the

components.

Before going to next stage, check the whole gotten and cross cheek against the

circuit diagram check for any freeing matter on the copper. The etching bath should

be in a galls or enamels disc. If using crystal of ferric-chloride, these should be

thoroughly dissolved in water to the proportional suggested. There should be 0.5 Lt.

of water for 125 Gm. of crystal.

Water liquid should be thoroughly deflated and druid in water land; never pour down

the drain. To prevent particles of copper hindering further etching, agitate the

solutions carefully be gently twisting or rocking the tray.

The board should not be left in the bath a moment longer than is needed to remove

just the right amount of copper. In spite of there being a resist coating there is no

protection against etching away through exposed copper edges; this leads to over

etching. Have running water ready so that etched board can be removed properly

and rinsed; this will hall etching immediately.

Drilling is one of those operations that call for great care because most of the holes

will be made a very small drill. For most purposes a 1 mm drill is used Drill all holes

with this size first those that need to be larger can be easily drilled again with the

appropriate lager size.

4.4. COMPONENT ASSEMBLES:

From the greatest variety of electronic components available today, which runs into

tent of thousands of different types it is often a perplexing task to know which the

right task for a given job is. There should be damage such as hair line crack intuit

opera on PCB that could age a seriousfiec on the operational ability to the completed

assemble. If there are than they can and should be repaired fiesta by soldering a

short link of bare copper wire over the affected part.

The most popular method of holding all the items is to been the wires future apart

after they even been indebted in the appropriate holes. This will hold the component

in position ready for soldering. Some components will be considerably larger than

other occupying and possible partially obscuring neighboring components. Because

of this best to start by mounting the smallest first and progressing through to the

largest. Before starting make certain that no further drilling I likely to be necessary

because access may be impossible later.

Next will probably be the resistor small signal diodes of other similar size

components some capacitor are very small but it would be best to fit these

afterwards when fitting each group of components marks of each one on the

components as it is fitted and if we have to leave the job we know where to

recommence. Although transistor & integrated circuit are small items there are good

reasons for leaving the soldering of these until the last step the main pint is that

these components are sensitive to heart and is subjected to prolonged application to

the soldering iron they could be internally damaged.

All the components before mounting are rubbed with sandpaper so that oxide layer is

removed from their tips. Now they are mounted according to the components layout.

SOLDERING TECHNIQUES:

A soldered connection ensures metal continuity. The soldering process involves:

Melting of the flux which in turn removes the oxide films on the metal to be soldered.

Melting the solder which removes the impurities. The solder partially dissolve the

metal in the connection. The solder cools and fuses with the metal.

The soldering technique involves knowledge of:

Soldering iron

Soldering wire

Soldering procedure

Replacing components

Prosecutions of when using C-MOS, devices

Knowledge of good and bad soldering joints.

4.5. SOLDERING & SOLDERING TECHNIQUES

Soldering Iron:

Soldering iron is an essential tool for soldering. A Soldering iron should give

sufficient heat a melt solder by heat transfer when the iron tip is applied to a

connection to be soldered. The selection of the soldering iron can be made as regard

to its tips size shape and wattage. Soldering iron temperature is selected and

controlled according to the work to be performed. Generally two types of soldering

irons are available: Soldering Pencil and Soldering Gun.

Soldering Pencils:

These are light weight soldering iron which can generate around 12 watts to 50 watts

of heat.

SOLDERING ALLOY

Soldering Materials:

The soldering material is used to join together two or more metals at temperatures

below their melting point. The solder alloy consists of Lead (37%) and Tin (63%).

The continuous connection between two metal joint is made by solder materials.

Most commonly used solder wire consists of 60% of Tin 40% Lead. This is in the

form of a hollow wire whose center is filled with an organic paste like material called

rosin. Its melting temperature is 190 degree centigrade.

FLUX:

Flux is a material used to aid soldering process. Flux is needed to scratch away the

small film of oxide on the surface of metals to be soldered. This flux forms a

protective film that prevents reoxidation while the connection is heated to the point at

which the solder melts. Flux is very helpful on old dusty, eroded joint.

SOLDERING PROCEDURE:

The soldering procedure involves selection of soldering iron cleaning of components

to be soldered and cleaning of the PCB to be soldered. The soldering iron should be

selected according to the job and should be powerful enough to provide heat. The tip

of the soldering iron should be selected as per the space available for soldering. The

component that has to be soldered should be properly bent and its leads should be

properly inserted in the PCB. Before if one has already identified the fault

component, then one should not try to remove or disorder the component. The

components should simply be cut and taken out.

4.6. PRECAUTIONS WHEN USING C-MOS DEVICES:

CMOS Devices are sensitive to static charges. So care has to be taken while

handling this device. Static charge is generated by rubbing cloth with human body or

by any other friction of human body. Before string or handling CMOS Devices

touching the ground or metallic chassis of the equipment, one can wear a metallic

band in hand which is connected to ground. The working table should be either of

wood or should have rubber sheet. The soldering iron tip should be static charge

free.

4.7. DESOLDERING TECHNIQUES

By using a disordering wick

By using a disordering pump

Disordering wick is made of fine copper wire mesh. When this is applied to the

heated components, the molten solder gets attached to the wire mesh by capillary

action. Disordering pump has a suction pump. The nozzle of the disordering pump is

kept to the heated component. The molten solder is sucked by a spring action.

Insertion in the PCB, the lead should be properly cleaned. After component has been

inserted it can be soldered. The oxide on the PCB can be removed by using flux,

sandpaper. The tip of the soldering iron should be clean and should have proper

shape. The shape of the tip normally gets bad over a period of time. The shape can

be made proper by filling. During soldering, excessive heat is generated at the

soldering iron tip. If the soldering iron tip is in contact with component for a longer

time then there is possibility of damage or may loose its characteristics. Place iron tip

at 45 degree to the PCB and component joint. Place the solder near the iron and let

it flow. Smoothen the area of joint by the soldering iron tip. By doing this, the molten

solder alloy flows into the PCB hole. Soldering should be done when the equipment

is off.

REPLACEMENT OF COMPONENT:-

In case of single sided PCB, the component to be removed can be disordered with

the help of iron and flux. The only precaution that has to be taken is that track should

not break while removing. In case of Through Hole PCB, care has to be taken so that

component while removing does not damage the Through Hole. In this case the

component is soldered on one side and the lead flows through the hole to the other

sides, so disordering and removing becomes very difficult and required practice.

4.8. CODING:

#include<reg51.h>

#include"serial.h"

#include"LCD_header.h"

#include<intrins.h>

sbit ds1=P1^2;

sbit sn1=P2^0;

sbit m1 =P2^1;

unsigned char received_char[40],sat,y,x,msg[40],msg_pos,tmp;

unsigned char time,rectime,first;

void Delay2()

{

int k,l;

for(k=0;k<=9000;k++)

{

for(l=0;l<=10;l++);

}

}

void read(void)

{

x=0;

// WriteData('Y');

do

{

received_char [x] = Rx_Character();

// WriteData(received_char [x]);

}

while(received_char [x++]!=0x0a);

x=0;

}

void intt () interrupt 4

{

EA=0;sat=1;

read();

read();

WriteData('Q');

if(received_char [4]=='I')

{

msg_pos= received_char [12]-48;

for(y=1;y<msg_pos;y++)

{

Send_String("AT+CMGD=");

Send_Character(y+48);

Send_Character(0x0D);

Send_Character(0x0A); Rx_Character();Rx_Character(); Rx_Character();Rx_Character();

}

_nop_(); _nop_();_nop_();

sat=0;

EA=1;

Send_String("AT+CMGR=");

Send_Character(msg_pos+48);

Send_Character(0x0D);

Send_Character(0x0A);

}

else

{

read();

for(x=0;x<40;x++){msg[x]=received_char [x];}

read();

read();

EA=1;

}

}

void main(void)

{

unsigned char tmpc,tmpc2;

sat=0;

Serial_Init();

Init_LCD();

P1=0;

received_char [0]=0;

Send_String("ATE0");

Send_Character(0x0D);

Send_Character(0x0A);

read();

read();

Send_String("AT+CMGF=1");

Send_Character(0x0D);

Send_Character(0x0A);read();read();

for(tmp<0;tmp<9;tmp++)

{

Send_String("AT+CMGD=");

Send_Character(tmp+48);

Send_Character(0x0D);

Send_Character(0x0A);read();read();

}

x=0;

WriteData('O');WriteData('K');

EA=1;

ES=1;

WriteCommand(0x01);

PrintLCD("PUMP:-ideal");

ds1=1;

while(1)

{

WriteCommand(0x01);

PrintLCD("PUMP:-ideal");

while (sat==0);

WriteCommand(0x01);

PrintLCD("time left=");

m1=1;

rectime=0;

rectime+=((msg[8]-48)*10);

rectime+=((msg[9]-48));

WriteCommand(0x8d);

WriteData(msg[8]);

WriteData(msg[9]);

first=1;

for(time=rectime;time>0;time--)

{

WriteCommand(0x01);

PrintLCD("time left=");

m1=0;

tmpc=time;

if(first==1)

{

first=0;

EA=0;

Send_String("at+cmgs=\"8962471551\"");Send_Character(0x0d);Send_Character(0x0a);

Send_String("PUMP ON");Send_Character(0x1a);read();read();read();read();

}

if(time==1)

{

EA=0;

Send_String("at+cmgs=\"8962471551\"");Send_Character(0x0d);Send_Character(0x0a);

Send_String("PUMP OFF");Send_Character(0x1a);read();read();read();read();

}

if(sn1)

{

EA=0;

Send_String("at+cmgs=\"8962471551\"");Send_Character(0x0d);Send_Character(0x0a);

Send_String("PUMP OFF at ");

tmpc2=tmpc/10;

Send_Character((tmpc2%10+48));tmpc=tmpc/10;

Send_Character((tmpc%10+48));tmpc=tmpc/10;

Send_String("sec");

Send_Character(0x1a);read();read();read();read();

}

while(sn1)

{

Delay2();

}

WriteCommand(0x8c);

WriteData(48+(tmpc%10)); tmpc=tmpc/10;

WriteCommand(0x8b);

WriteData(48+(tmpc%10)); tmpc=tmpc/10;

Delay2();

}

m1=1;

sat=0;

}

}

1.5. TABLE OF COMPONENT PRICE

S.no.

Component Name Component value

Component Quantity

Component Price(Rs.)

1Crystal MHz) (11.0592)

MHz1 25

2Capacitor (33pf) 33pf 2 30

3RST BANK (104) 1 7

4IC BASE (40PIN) 2 17

5CHAR. LCD (JHD16*2) 1 80

6POT (103) 1 12

7VOLATAGE REGULATOR

(7805) 1 80

8 MICRO- CONTROLLER

P89V51RD2B (16KB)

1 400

9DIODES 1N4007 10 16

10 Capacitor1F

104pF

1000F

10 24

11 PCB “6 X 8”1 35

12 Cooler Motor 220Vac1 150

13 Opt coupler (MCT2E)2 40

14 Resistance (10k) 8 15

15 Switch Driver IC (ULN2800)

1 14

16 Relay (12v) 1 18

17 Battery (9v) (12v) 1 20

18 Soldering Wire 1 15

19 Connecting wires 2 5

20 Soldering Paste 1 10

5.1 ADVANTAGES

1. Highly sensitive

2. Fit and forget system

3. Complete elimination of manpower

4. This project controls the on-off action of the motor in the field

5. Low cost and easy to implement.

6. Can cover maximum area in a field

5.2 DISADVANTAGES

• Difficult in case of failure of GSM modem

• Kit is to be protected from reaching water.

6. Application:

1. Home garden.

2. Agriculture land.

3. Manual on/ off imitation through SMS

7. CONCLUSION

The project “GSM BASED AUTOMATIC IRRIGATION SYSTEM” has been

successfully designed and tested.

It has been developed by integrating features of all the hardware components used.

Presence of every module has been reasoned out and placed carefully thus

contributing to the best working of the unit. Thus monitoring the functioning of the

motor automatically using GSM technology got designed with the specific

parameters.

Secondly, using highly advanced IC’s and with the help of growing technology the

project has been successfully implemented.

This is a very useful technique to control the motor functioning.

• By using Microcontroller, we Controlled the on off action of the motor.

• It is mainly useful in the areas where the power fluctuations are high.

Data Sheet -1

P89V51RD2 (Microcontroller)

1. General description

The P89V51RD2 is an 80C51 microcontroller with 64 kB Flash and 1024 bytes of

data RAM. A key feature of he P89V51RD2 is its X2 mode option. The design

engineer can choose to run the application with the conventional 80C51 clock rate

(12 clocks per machine cycle) or select the X2 mode (6 clocks per machine cycle) to

achieve twice the throughput at the same clock frequency. Another way to benefit

from this feature is to keep the same performance by reducing the clock frequency

by half, thus dramatically reducing the EMI. The Flash program memory supports

both parallel programming and in serial In-System Programming (ISP). Parallel

programming mode offers gang-programming at high speed, reducing programming

costs and time to market. ISP allows a device to be reprogrammed in the end

product under software control. The capability to field/update the application

firmware makes a wide range of applications possible. The P89V51RD2 is also In-

Application Programmable (IAP), allowing the Flash program memory to be

reconfigured even while the application is running.

2. Features

5 V Operating voltage from 0 to 40 MHz 64 kB of on-chip Flash program memory with ISP (In-System Programming)

and IAP (In-Application Programming) Supports 12-clock (default) or 6-clock mode selection via software or ISP SPI (Serial Peripheral Interface) and enhanced UART PCA (Programmable Counter Array) with PWM and Capture/Compare

functions Four 8-bit I/O ports with three high-current Port 1 pins (16 mA each) Three 16-bit timers/counters Programmable Watchdog timer (WDT)

4. Functional description

Memory organization

The device has separate address spaces for program and data memory.

Flash program memory

There are two internal flash memory blocks in the device. Block 0 has 64 kbytes and contains

the user’s code. Block 1 contains the Philips-provided ISP/IAP routines and may be enabled

such that it overlays the first 8 kbytes of the user code memory. The 64 kB Block 0 is

organized as 512 sectors, each sector consists of 128 bytes. Access to the IAP routines may

be enabled by clearing the BSEL bit in the FCF register. However, caution must be taken

when dynamically changing the BSEL bit. Since this will cause different physical memory to

be mapped to the logical program address space, the user must avoid clearing the BSEL bit

when executing user code within the address range 0000H to 1FFFH.

Data RAM memory

The data RAM has 1024 bytes of internal memory. The device can also address up to

64 kB for external data memory.

Expanded data RAM addressing

The P89V51RD2 has 1 kB of RAM. See Figure 5 “Internal and external data memory

Structure.”

The device has four sections of internal data memory:

1. The lower 128 bytes of RAM (00H to 7FH) are directly and indirectly addressable.

2. The higher 128 bytes of RAM (80H to FFH) are indirectly addressable.

3. The special function registers (80H to FFH) are directly addressable only.

4. The expanded RAM of 768 bytes (00H to 2FFH) is indirectly addressable by the

Move external instruction (MOVX) and clearing the EXTRAM bit. (See ‘Auxiliary Register

(AUXR) in Section 6 “Special function registers” Since the upper 128 bytes occupy the same

addresses as the SFRs, the RAM must Be accessed indirectly. The RAM and SFRs space are

physically separate even Though they have the same addresses.

9. REFERENCES

[1]. H.G. Rodney Tan, C. H. Lee and V. H. Mock, “Automatic Power Meter Reading

System Using GSM Network” IPEC 2007, International power engineering

conference, PP. 465 – 469, Dec 3-6, 2007.

[2]. Li Li, Xiaoguang Hu and Weicun Zhang, “Design of an ARM Based Power Meter

Having Wi-Fi Wireless Communication Module” ICIEA 2009, 4th IEEE conference on

Industrial Electronics and Applications, PP. 403 – 407, May 25-27, 2

WEBREFERENCES:

1.http://www.datasheetarchive.com/LPC2194/P89V51RD2%20microcontroller-

datasheet.html

2. http://www.engineersgarage.com/electronic-components/max232-datasheet

3. http://www.engineersgarage.com/articles/gsm-gprs-modules

4. http://www.nelsotech.com/products/pump-controller/gsm-pump-controller.php