merged report

8/11/2019 Merged Report

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CHAPTER 1

INTRODUCTION TO ORGANISATION

1.1 CETPA INFOTECH:

CETPA Infotech, an ISO 9001:2008 Certified Company is a renowned name among

Engineering Students and MCA/BCA professionals for providing quality education in the

forms of 6 Months,6 weeks Summer, Industrial & Winter Training. CETPA has formed a

group of enthusiastic and well competent professionals, having a unique training

methodology which makes CETPA Northern India No-1 Training Company with a bright

history of training more than 35,000 engineers and professionals.CETPA Infotech has

designed a curriculum for 6 Weeks and 6 Months training which incorporates a blending

learning approach by integrating classroom, hands on lab exercise and team projects to

provide students both the theoretical & practical training, needed to build strong technical

skills.Cetpa Infotech provides Training/Internship/ Winter Training Programs cum

Placement on .NET, C & C++, VHDL,Verilog HDL, Embedded System, Advance

Embedded System using pic,avr microcontroller, Mechanical Designing

(CATIA,CREO),Advance Networking(CCNA and MCIP),J2EE,Software Testing,VLSI

design for Engineering Students at CETPA Noida, Greater Noida, Lucknow,

Roorkee,Mohali, Kyiv(Ukraine) & Schwerin (Germany). Company goal is to achieve

highest possible recognition through professionalism, technological contributions,

industry oriented education & training, research & development.We are very experienced

Software development company providing high quality and cost effective Software

development serivces using latest technologies .


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CHAPTER 2

INTRODUCTION TO EMBEDDED SYSTEMS

2.1 INTRODUCTION:

An embedded system is a special-purpose system in which the computer is completely

encapsulated by the device it controls. Unlike a general-purpose computer, such as a

personal computer, an embedded system performs pre-defined tasks, usually with very

specific requirements. Since the system is dedicated to a specific task, design engineers

can optimize it, reducing the size and cost of the product. Embedded systems are often

mass-produced, so the cost savings may be multiplied by millions of items.

Handheld computers or PDAs are generally considered embedded devices because of the

nature of their hardware design, even though they are more expandable in software terms.

This line of definition continues to blur as devices expand.

Physically, embedded systems range from portable devices such as digital

watches and MP3 players, to large stationary installations like traffic lights, factory

controllers. Complexity varies from low, with a single microcontroller chip, to very high

with multiple units, peripherals and networks mounted inside a large chassis or enclosure.

Embedded systems contain processing cores that are either microcontrollers or digital

signal processors (DSP). The key characteristic, however, is being dedicated to handle a

particular task. Since the embedded system is dedicated to specific tasks, design

engineers can optimize it to reduce the size and cost of the product and increase the

reliability and performance. Some embedded systems are mass-produced, benefiting

from economies of scale.

Robotics and automation are a part of embedded systems itself. Robot development and

automation needs study of embedded systems.


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Examples of Embedded System are

1. automatic teller machines (ATMs)

2. avionics, such as inertial guidance systems, flight control hardware/software and

other integrated systems in aircraft and missiles

3. cellular telephones and telephone switches

4. computer equipment such as routers and printers

5. engine controllers and antilock brake controllers for automobiles

6. home automation products, like thermostats, air conditioners, sprinklers, and

security monitoring systems

7. handheld calculators

8.

household appliances, including microwave ovens, washing machines, television

sets

9. medical equipment

10.handheld computers

11.videogame consoles

2.2 CHARACTERISTICS OF EMBEDDED SYSTEMS:

Embedded systems are designed to do some specific task, rather than be a general-

purpose computer for multiple tasks. Some also have real-timeperformance constraints

that must be met, for reasons such as safety and usability; others may have low or no

performance requirements, allowing the system hardware to be simplified to reduce costs.

The program instructions written for embedded systems are referred to as firmware, and

are stored in read-only memory or Flash memory chips. They run with limited computer

hardware resources: little memory, small or non-existent keyboard or screen.

Many embedded systems consist of small, computerized parts within a larger device that

serves a more general purpose. For example- a line follower autonomous robot which

follows a specific path and moves accordingly to the path.


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The embedded systems are special purpose computer systems designed to perform only

the specific purposes. For Example- a system designed to display numbers cannot be used

to operate motors.

Embedded systems range from no user interface at alldedicated only to one taskto

complex graphical user interfaces that resemble modern computer desktop operating

systems. Simple embedded devices use buttons, LEDs, graphic or character LCDs (for

example popular HD44780 LCD) with a simple menu system.

2.3 MICROCONTROLLER

Microcontrollers are single chip computers. The Intel 8051 is a single chip

microcontroller (C) which was developed by Intel in 1980 for use in embedded systems.

Intel's original versions were popular in the 1980s and early 1990s, but has today largely

been superseded by a vast range of faster and/or functionally enhanced 8051-compatible

devices manufactured by more than 20 independent manufacturers including Atmel,

Infineon Technologies (formerly Siemens AG), Maxim Integrated Products (via its Dallas

Semiconductor subsidiary), NXP (formerly Philips Semiconductor), Winbond, ST

Microelectronics, Silicon Laboratories (formerly Cygnal), Texas Instruments and Cypress

Semiconductor. Intel's official designation for the 8051 family of Cs is MCS 51.Intel's

original 8051 family was developed using NMOS technology, but later versions,

identified by a letter "C" in their name, e.g. 80C51, used CMOS technology and were less

power-hungry than their NMOS predecessors - this made them eminently more suitable

for battery-powered devices.

IMPORTANT FEATURES:

It provides many functions (CPU,RAM,ROM,I/O, interrupt logic, timer, etc.) in

a single package .

8-bit data bus - It can access 8 bits of data in one operation (hence it is an 8-bit

microcontroller).
http://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Random_access_memoryhttp://en.wikipedia.org/wiki/Read-only_memoryhttp://en.wikipedia.org/wiki/Read-only_memoryhttp://en.wikipedia.org/wiki/Random_access_memoryhttp://en.wikipedia.org/wiki/Central_processing_unit


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16-bit address bus - It can access 216

memory locations - 64kB each of RAM and

ROM.

On-chip RAM - 128 bytes ("Data Memory")

On-chip ROM - 4 kb ("Program Memory").

Four byte bi-directional input/output port.

UART (serial port).

Two 16-bit Counter/timers.

Two-level interrupt priority.

2.4 PROCESSORS IN EMBEDDED SYSTEMS

Embedded processors can be broken into two broad categories. Ordinary microprocessors

(P) use separate integrated circuits for memory and peripherals. Microcontrollers (C)

have many more peripherals on chip, reducing power consumption, size and cost. In

contrast to the personal computer market, many different basic CPU architectures are

used, since software is custom-developed for an application and is not a commodity

product installed by the end user. RISC as well as non-RISC processors are found. Word

lengths vary from 4-bit to 64-bits and beyond, although the most typical remain 8/16-bit.

2.5 MICROCONTROLLERS AND MICROPROCESSORS

Table 2.1: Difference between Microprocessor and Microcontroller

Microcontrollers Microprocessors

1. A Microcontroller (sometimes

abbreviated C, uC or MCU) is a small

computer on a single integrated

circuit containing a processor core,

memory, and

programmable input/output peripherals.

1. A Microprocessor is an IC which has

only the CPU inside them i.e. only the

processing powers such as Intels

Pentium 1,2,3,4, core 2 duo, i3, i5 etc.
http://en.wikipedia.org/wiki/Kilobytehttp://en.wikipedia.org/wiki/Kilobyte


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2. Microcontrollers are designed to

perform specific tasks. Specific means

applications where the relationship of

input and output is defined. Depending

on the input, some processing needs to

be done and output is delivered. For

example, keyboards, mouse, washing

machine, digicam, pen drive, remote,

microwave, cars, bikes, telephone,

mobiles, watches, etc.

2. Microprocessor find applications

where tasks are unspecific like

developing software, games, websites,

photo editing, creating documents etc.

3. Since the applications are very

specific, they need small resources like

RAM, ROM, I/O ports etc. and hence

can be embedded on a single chip.

3. In such cases the relationship

between input and output is not defined.

They need high amount of resources like

RAM, ROM, I/O ports etc. So needs

external RAM, ROM and Memory.

4. The microcontrollers operate from a

few MHz to 30 to 50 MHz

4. The microprocessor operates above

1GHz as they perform complex tasks.

5.The microcontroller is designed for

embedded applications. Microcontrollersare used in automatically controlled

products and devices, such as

automobile engine control systems,

implantable medical devices, remote

controls, office machines, appliances,

power tools, toys and other embedded

systems.

5. The microprocessors are used

in personal computers or other generalpurpose applications such as for laptops

and heavy applications where

complexity is more and memory

requirements are high.


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2.6 MICROCONTROLLER FAMILIES

8051- These microcontrollers are old but still trendy and most of the companies fabricate

these microcontrollers. The older types of 8051 have 12 clocks per instruction that make

it sluggish whereas the recent 8051 have 6 clocks per instruction. The 8051

microcontroller does not have an in built memory bus and A/D converters. In 1980, Intel

fabricated the single chip microcontroller 8051 with Harvard architecture.

PIC- Programmable Interface Controller is usually referred as PIC. They are slightly

older than 8051 microcontrollers but excel cause of their small low pin count devices.They perform well and are affordable. The Microchip technology fabricated the single

chip microcontroller PIC with Harvard architecture. The programming part is very

tedious and hence it is not recommended for beginners.

AVR (Advanced Version RISC) - In 1996, Atmel fabricated this single chip

microcontroller with a modified Harvard Architecture.

2.7 8051 MICROCONTROLLER

The most commonly used microcontroller is 8051 families AT89C51 microcontroller

which is produced by Atmel. It is widely used in most of the application for having an

advantage of simple programming and low cost.

2.7.1 AT89C51

AT89C51 is an 8-bit, 40 pin microcontroller that belongs to Atmel's 8051

family. ATMEL 89C51has 4KB of Flash programmable and erasable read only memory

(PEROM) and 128 bytes of RAM. It can be erased and program to a maximum of 1000

times.


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In 40 pin AT89C51, there are four ports designated as P1, P2, P3and P0. All these ports

are 8-bit bi-directional ports, i.e., they can be used as both input and output ports. Except

P0which needs external pull-ups, rest of the ports have internal pull-ups. When 1s are

written to these port pins, they are pulled high by the internal pull-ups and can be used as

inputs. These ports are also bit addressable and so their bits can also be accessed

individually

.

2.7.2 SALIENT FEATURES OF AT89C51-

4K Bytes of In-System Reprogrammable Flash Memory

Fully Static Operation: 0 Hz to 24 MHz

Three-level Program Memory Lock

28 x 8-bit Internal RAM

32 Programmable I/O Lines

Two 16-bit Timer/Counters

Six Interrupt Sources

Programmable Serial Channel

Low-power Idle and Power-down Modes

40-pin DIP

8051 BLOCK DIAGRAM:


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Fig.2.1: 8051 Block diagram

2.7.3 USES OF MICROCONTROLLERS

Microcontrollers are used in automatically controlled products and devices, such as

automobile engine control systems, implantable medical devices, remote controls, office

machines, appliances, power tools, and toys. By reducing the size and cost compared to a

design that uses a separate microprocessor, memory, and input/output devices,

microcontrollers make it economical to digitally control even more devices and

processes. Mixed signal microcontrollers are common, integrating analog componentsneeded to control non-digital electronic systems.Even pulses generated by the oscillator

enable harmonic and synchronous operation of all circuits within the microcontroller. It is

usually configured as to use quartz-crystal or ceramics resonator for frequency

stabilization. It can also operate without elements for frequency stabilization (like RC

oscillator). It is important to say that program instructions are not executed at the rate


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imposed by the oscillator itself, but several times slower. It happens because each

instruction is executed in several steps. For some microcontrollers, the same number of

cycles is needed to execute any instruction, while it's different for other microcontrollers.

Accordingly, if the system uses quartz crystal with a frequency of 20MHz, the execution

time of an instruction is not expected 50nS, but 200, 400 or even 800 nsec, depending on

the type of the microcontroller.

Timers/Counters

Most programs use these miniature electronic "stopwatches" in their operation. These are

commonly 8- or 16-bit SFRs the contents of which is automatically incremented by each

coming pulse. Once the register is completely loaded, an interrupt is generated.If these

registers use an internal quartz oscillator as a clock source, then it is possible to measure

the time between two events (if the register value is T1 at the moment measurement has

started, and T2 at the moment it has finished, then the elapsed time is equal to the result

of subtraction T2-T1 ). If the registers use pulses coming from external source, then such

a timer is turned into a counter. This is only a simple explanation of the operation itself.

Its somehow more complicated in practice.

Input/output ports (I/O Ports)

In order to make the microcontroller useful, it is necessary to connect it to peripheral devices.

Each microcontroller has one or more registers (called a port) connected to the microcontroller

pins.

Special Function Registers (SFR)

Special function registers are part of RAM memory. Their purpose is predefined by the

manufacturer and cannot be changed therefore. Since their bits are physically connected

to particular circuits within the microcontroller, such as A/D converter, serial

communication module etc., any change of their state directly affects the operation of the


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microcontroller or some of the circuits. For example, writing zero or one to the SFR

controlling an input/output port causes the appropriate port pin to be configured as input

or output. In other words, each bit of this register controls the function of one single pin.

Program Counter

Program Counter is an engine running the program and points to the memory address

containing the next instruction to execute. After each instruction execution, the value of

the counter is incremented by 1. For this reason, the program executes only one

instruction at a time just as it is written. However the value of the program counter can be

changed at any moment, which causes a jump to a new memory location. This is how

subroutines and branch instructions are executed. After jumping, the counter resumes

even and monotonous automatic counting +1, +1, +1

Central Processor Unit (CPU)

As its name0 suggests, this is a unit which monitors and controls all processes within the

microcontroller and the user cannot affect its work. It consists of several smaller subunits,

of which the most important are:

Instruction decoder

It is a part of the electronics which recognizes program instructions and runs other

circuits on the basis of that. The abilities of this circuit are expressed in the "instruction

set" which is different for each microcontroller family.

Arithmetical Logical Unit (ALU)performs all mathematical and logicaloperations upon data.


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PIN DIAGRAM

Fig.2.2: pins 32-39(8051 microcontroller)

Fig 2.3: pins 1-7 (8051 microcontroller)


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Fig 2.4: Various pins (8051 microcontroller)

ALE/PROG:

Address Latch Enable output pulse for latching the low byte of the address during

accesses to external memory. ALE is emitted at a constant rate of 1/6 of the oscillator

frequency, for external timing or clocking purposes, even when there are no accesses to

external memory. (However, one ALE pulse is skipped during each access to external

Data Memory.) This pin is also the program pulse input (PROG) during EPROM

programming.

PSEN:

Program Store Enable is the read strobe to external Program Memory. When the device is

executing out of external Program Memory, PSEN is activated twice each machine cycle

(except that two PSEN activations are skipped during accesses to external Data Memory).

PSEN is not activated when the device is executing out of internal Program Memory.


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EA:

When EA is held high the CPU executes out of internal Program Memory (unless the

Program Counter exceeds 0FFFH in the 80C51). Holding EA low forces the CPU to

execute out of external memory regardless of the Program Counter value. In the 80C31,

EA must be externally wired low. In the EPROM devices, this pin also receives the

programming supply voltage (VPP) during EPROM programming.

XTAL1:

Input to the inverting oscillator amplifier. The quartz crystal oscillator connected to

XTAL1 also needs a capacitor of 30 pf value as shown in figure2.One side of a

capacitor is grounded.

XTAL2:

Output from the inverting oscillator amplifier. The quartz crystal oscillator connected to

XTAL2 also needs a capacitor of 30 pf value as shown in figure2.One side of a

capacitor is grounded.

Fig 2.5: Crystal Diagram

RST:

Pin 9 is the RESET pin. It is an input and is active high (normally low). Upon applying a

high pulse to this pin, the microcontroller will reset and terminate all activities. This is


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often referred to as a poweron reset. Activating a power-on reset will cause all values in

the registers to be lost. It will set program counter to all 0s.

RESET values of some 8051 registers

Table 2.2: RESET values of some 8051 registers

Register RESET values

PC 0000

ACC 0000

B 0000

PSW 0000

SP 0007

DPTR 0000

Port 0(pins 32 to 39):

Port 0 is an 8-bit open drain bidirectional port. As an open drain output port, it can sink

eight LS TTL loads. Port 0 pins that have 1s written to them float, and in that state will

function as high impedance inputs. Port 0 is also the multiplexed low-order address and

data bus during accesses to external memory. In this application it uses strong internal

pull-ups when emitting 1s. Port 0 emits code bytes during program verification. In this

application, external pull-ups are required.


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Port 1(Pins 1 to 8):

Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. Port 1 pins that have 1s

written to them are pulled high by the internal pull-ups, and in that state can be used as

inputs. As inputs, port 1 pins that are externally being pulled low will source current

because of the internal pull-ups.

Port 2(Pins 1 to 8):

Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. Port 2 emits the high-order

address byte during accesses to external memory that use 16-bit addresses. In this

application, it uses the strong internal pull-ups when emitting 1s.Port 2 is also designated

as A8-A15, indicating its dual function. When the 8051 is connected to external memory,

P2 is used for the upper 8 bits of the 16-bit address

.Port 3(pins 32 to 39):

Port 3 occupies a total of 8 pins, pins 10 through 17.It can be used as input or output. Port

3 is an 8-bit bidirectional I/O port with internal pull-ups. It also serves the functions of

various special features of the 80C51. Port 3 has the additional function of providingsome extremely important signals such as interrupts.


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CHAPTER 3

PROJECT WORK

3.1 INTERFACING DEVICES WITH

8051 MICROCONTROLLER

3.2 LCD INTERFACING

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. For

interfacing an LCD with 8051, we give VCC to pins 2 and 15 and a Gnd to pins 1 and 16.

A pot (Variable resistor) is connected to pin no 3 or VEE by which we can control the

contrast of the LCD. The RS pin is the Register select pin if we give a logical 0 from our

8051 microcontroller to this pin we can send command to the LCD. If we give a Logical

1 from our 8051 microcontroller to this pin we can send data to the LCD.

1.Command/Instruction Register

Stores the command instructions given to the LCD. A command is an instruction given to

LCD to do a predefined task like

Initializing, clearing the screen, setting the cursor position, controlling display etc.

2.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.


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Fig 3.4 LCD Interfacing With 8051

3.2.1 CODE:

#include

sbit RS= P3^0;

sbit RW= P3^1;

sbit EN= P3^2;

void delay(unsigned int time)

{

int k,m;

for(k=0;k


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RS=1;

RW=0;

EN=1;

delay(10);

EN=0;

}

void Lcmd (unsigned char y)

{

P2=y;

RS=0;

RW=0;

EN=1;

delay(10);

EN=0;

}

unsigned char f[5] = {"CETPA"};

unsigned char s[8] ={"INFOTECH"};

int i,j;

void main()

{

while(1)

{

Lcmd(0x38);

Lcmd(0x01);

Lcmd(0x0e);

Lcmd(0x06);

Lcmd(0x85);

Lcmd(0x04);

for(i=4;i>=0;i--)

{

Ldata(f[i]);


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delay(10);

}

Lcmd(0x87);

for(j=7;j>=0;j--)

{

Ldata(s[j]);

delay(10);

}

}

}

3.4LCD BASED TEMPERATURE SENSOR USING

MICROCONTROLLER (AT89C51)

3.4.1 DESCRIPTION:

This project is design for the student to make them understand the technology used in a

now a days Temperature Sensor system, which is used in whole world. The Temperature

Sensor is programmed for the specific operation. Every operation on the Temperature

Sensor is defined is display on the monitor.

3.4.2 PROJECT SUMMARY:

In this project we try to give the Idea of prototype voting machines. We are using micro

controller AT89C51 for controlling the voting operation. The Temperature Sensor is

designed for Four Political parties. There is a LCD display for showing the status of

voting by interfacing the Temperature Sensor with the PC.
http://www.engineersgarage.com/microcontroller/8051projects/LCD-based-digital-clock-AT89C51-circuithttp://www.engineersgarage.com/microcontroller/8051projects/LCD-based-digital-clock-AT89C51-circuithttp://www.engineersgarage.com/microcontroller/8051projects/LCD-based-digital-clock-AT89C51-circuithttp://www.engineersgarage.com/microcontroller/8051projects/LCD-based-digital-clock-AT89C51-circuithttp://www.engineersgarage.com/microcontroller/8051projects/LCD-based-digital-clock-AT89C51-circuit


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3.4.3 FEATURES:

Easy to use for day to day operation.

Stand alone deviceno computer or any other hardware required.

Needs to be programmed only once. Easy to program.

3.4.4 BENEFITS:

No need to assign a person

No manual intervention

Saves man power and money

Easy programming with the help of manual.

Table 3.1 Components Used

Sr. no. Component used Quantity

1. AT 89c51 Micro controller (base +IC) 1

2. Rectifier(12 volt 1 ampere) 1

3. Resistance (1kohm) 1

4. Resistance (4.7kohm) 1

5. Resistance(8.2kohm) 1

6. Transformer (220v-909) 1

7. LEDs 1

8. Electrolytic capacitor (10 microfarad) 1

9. Electrolytic capacitor (1000 microfarad) 1

10. Electrolytic capacitor (33 pico farad) 2

11. 3-Pin connector 1


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12. 8-pin connector 1

13. Push switches 7

14. Cello tape (for electrical use) 1

15. Potentiometer (10k value) 1

16. LCD(2*16) 1

17. Crystal oscillator (11.0592Mhz frequency) 1

18. L7805CN (voltage regulator) 1

3.4.5 SOURCE CODE://Program to display temperature in Celsius and Farenheit scale.

#include

#define port P3

#define adc_input P1

#define dataport P0

#define sec 100

sbit rs = port^0;

sbit rw = port^1;

sbit e = port^2;

sbit wr= port^3;

sbit rd= port^4;

sbit intr= port^5;

int test_intermediate3=0,

test_final=0,test_intermediate1[10],test_intermediate2[3]={0,0,0};

void delay(unsigned int msec )


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{

int i ,j ;

for(i=0;i


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while(str[i]!='\0')

{

lcd_data(str[i]);

i++;

delay(10);

}

return;

}

void shape() // Function to make the shape of degree symbol

{

lcd_cmd(64);

lcd_data(2);

lcd_data(5);

lcd_data(2);

lcd_data(0);

lcd_data(0);

lcd_data(0);

lcd_data(0);

lcd_data(0);

}

void convert() // Function to convert the values of ADC into numeric value to be sent

to LCD

{

int s;

lcd_cmd(0x81);

delay(2);

lcd_data_string("TEMP:");

test_final=(((9*test_intermediate3)/5)+32);

s=test_final/100;


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test_final=test_final%100;

lcd_cmd(0x88);

if(s!=0)

lcd_data(s+48);

else

lcd_cmd(0x06);

s=test_final/10;


lcd_data(s+48);

lcd_data(test_final+48);

lcd_data(0);

lcd_data('F');

lcd_data(' ');

test_final=test_intermediate3;

lcd_cmd(0xc1); //Setting cursor to first position of first line

delay(2);

lcd_data_string("TEMP:");

s=test_final/100;


lcd_cmd(0xc8);

if(s!=0)

lcd_data(s+48);

else

lcd_cmd(0x06);

s=test_final/10;


lcd_data(s+48);

lcd_data(test_final+48);

lcd_data(0);

lcd_data('c');


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lcd_data(' ');

delay(2);

}

void main()

{

int i,j;

adc_input=0xff;

lcd_cmd(0x38); //2 Line, 5X7 Matrix display

lcd_cmd(0x0c); //Display On, Cursor blinking

delay(2);

lcd_cmd(0x01); // clear screen

delay(2);

while(1)

{

for(j=0;j


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}

for(i=0;i


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The purpose of our project was to create an inexpensive and high-efficient electronic

Temperature Sensor . In the conclusion of this report, the machine was able to display to

us which candidate has won ,how much votes did he received whether it was tie or not.

The specific work we have finished are as follows:

We successfully modified the electronic Temperature Sensor with a few

components to add two more functions to the main body, namely the LCD display

and led.

We tested and optimized the AT89C51 development board designed and

produced by Cetpa lab in a large scale, which was used to control the voting

smoothly.

We choose the LCD, switches at a relatively low cost, fixed them and adjusted

them on the development board.

Currently an EVM can record a maximum of 999 votes, which is sufficient for a

polling station .

It is not possible to vote more than once by pressing the button again and again

.As soon as a initialize button is pressed, the vote is recorded for that particular

candidate.

Future Scope

Currently an EVM can record a maximum of 999 votes, which is not sufficient for a

polling station therefore we can maximize this voting number upto thousands so that the

voting number should be increased and some type of security should be introduced so

that no theft will be taken with the number of votes.


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BOOKS REFERENCES

[1] SEDRA SMITH, MICROELECTRONIC CIRCUITS (2002), 5TH

EDITION

[2] INTRODUCTION TO 8051 MICROCONTROLLER, Author Mazidi.

Publisher, Pearson Education, 2007

[3] INTRODUCTION TO 8051 MICROCONTROLLER, Author AYALA

(3RD

EDITION)

[4] KJ.AYALA, The 8051 Microcontroller -. Pen rams International.

[5] Intel's manual on EmbeddedMicrocontrollers"


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The LM35 - An Integrated Circuit Temperature Sensor

Why Use LM35s To Measure Temperature?

o You can measure temperature more accurately than a

using a thermistor.o The sensor circuitry is sealed and not subject to

oxidation, etc.

o The LM35 generates a higher output voltage than

thermocouples and may not require that the output

voltage be amplified.

What Does An LM35 Look Like?

o

Here it is.

What Does an LM35 Do? How does it work?

o It has an output voltage that is proportional to the

Celsius temperature.

o The scale factor is .01V/oC

o The LM35 does not require any external calibration or

trimming and maintains an accuracy of +/-0.4

o

C at roomtemperature and +/- 0.8 oC over a range of 0 oC to

+100oC.

o Another important characteristic of the LM35DZ is that

it draws only 60 micro amps from its supply and

possesses a low self-heating capability. The sensor self-


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heating causes less than 0.1 oC temperature rise in still

air.

merged report

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