customized electronic dictionary

8/3/2019 Customized Electronic Dictionary

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DECLARATION

We hereby declare that this submission is our own work and that, to the best of our

knowledge and belief, it contains no material previously published or written by another

person nor material which to a substantial extent has been accepted for the award of any

other degree or diploma of the university or other institute of higher learning, except

where due acknowledgement has been made in the text.

Ashish Kumar Gupta

0509131026

Pulkit Maheshwari

0509131071

Shubham Sinha

0509131097

Date : 21st April 2009


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CERTIFICATE

This is to certify that Project Report entitled Electronic Dictionary submitted by Pulkit

Maheshwari, Ashish Kumar Gupta and Shubham Sinha in partial fulfillment of the

requirement for the award of degree Bachelor of Technology in Department of

Electronics & Communication of JSSATE (U.P. Technical University,Lucknow), is a

record of the candidates own work carried out by him under my supervision. The matter

embodied in this thesis is original and has not been submitted for the award of any other

degree.

Date :

Prof. Dinesh Chandra

JSSATE,

Noida

ACKNOWLEDGEMENT


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We owe special debt of gratitude to our Project Guide, Mrs. Monica Malikfor providing

her valuable support, guidance and worthy suggestions during various stages of our

project Mrs. Chhaya Grover and Mrs. KHNV Laxmi for their extreme cooperation and

generous help. Without their help and support this project would not have reached to its

completion.

We are also thankful to Mr. Uday (Project Coordinator, Department of EC) for her kind

help and guidance in completion of the project.

We are also grateful to all the staff of our EC Department & the institute and our friends

whose contribution in this effort was appreciable. They have been very helpful for the

entire period and have been a great source of inspiration for us.

Ashish Kumar Gupta

0509131026

Pulkit Maheshwari

0509131071

Shubham Sinha

0509131097

ABSTRACT


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An embedded system is a special-purpose computersystem designed to perform one or a

few dedicated functions often with real-time computing constraints. It is usually embedded

as part of a complete device including hardware and mechanical parts. Since the

embedded system is dedicated to specific tasks, design engineers can optimize it, reducing

the size and cost of the product, or increasing the reliability and performance. Some

embedded systems are mass-produced, benefiting from economies of scale.

Embedded systems can also be used to meet the daily requirements. The inspiration of this

project is the need of a specific dictionary for candidates preparing for competitive exams

like GRE, GMAT, CAT etc These exams require candidates to learn a specific list of

words to enhance their vocabulary skills. Further, a customised dictionary can also be used

to store general words in different foreign languages for tourists.

The electronic dictionary can be scaled down to a very compact size that can fit into a

pocket and can be customized for any purpose. By changing the program it can be filled

with any list of words the user desires.

The electronic dictionary has a compact keyboard interface and a programmable LCD

(graphical LCD will be used to display foreign languages). Further to accommodate a

large number of words an external memory or a microcontroller with large memory is

used.

The searching algorithm used here is a modified version of binary string search, where

first a pointer takes the control to the list of words starting with the first letter of the input

word. Then the ASCII code of the second letter of the middle word in the list is matched

with the second letter of the input word. Based on the comparison, the search then shortens

down to the upper half or lower half of the list. This process continues until the desired

word is found.

The electronic dictionary finds any word stored in its database in 100 milliseconds. This

delay is set to constant in all the words to obtain uniformity. There are no cases of

incorrect item matching or failure to find a word. It is completely efficient.

TABLE OF CONTENTS
http://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Real-time_computinghttp://en.wikipedia.org/wiki/Economies_of_scalehttp://en.wikipedia.org/wiki/Real-time_computinghttp://en.wikipedia.org/wiki/Economies_of_scalehttp://en.wikipedia.org/wiki/Computer


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DECLARATION.................................................................................................................2

CERTIFICATE....................................................................................................................3

ACKNOWLEDGEMENT...................................................................................................4

ABSTRACT.........................................................................................................................5

LIST OF FIGURES.8

LIST OF TABLES.. ....9

CHAPTER 1 INTRODUCTION....11

1.1INTRODUCTION TO MICROCONTROLLERS...111.2FEATURES AND FUNCTIONS OF ATMEGA 32L.....15

1.3PIN CONFIGURATION..18

CHAPTER 2 LCD AND ITS INTERFACING..19

2.1 LCD AND ITS WORKING PRINCIPLE....19

2.2 LIQUID CRYSTAL MATERIAL....21

2.3 FEATURES AND SPECIFICATIONS OF 16X2 LCD......23

2.4 INTERFACING OF LCD WITH MICROCONTROLLER.26

CHAPTER 3 MATRIX KEYPAD AND INTERFACING...27

3.1 THE MATRIX CIRCUIT..27

3.2 SCANNING TO DETECT KEY PRESSES.28

3.3 INTERFACING OF 4X4 KEYPAD MATRIX WITH ATMEGA 32L..33

CHAPTER 4 COMPLETE CIRCUIT INTERFACING36

4.1 INTERFACING OF TWO ATMEGA 32L..36

4.2 COMPLETE CIRCUIT DIAGRAM38

CHAPTER 5 ALGORITHM...39

5.1 BINARY SEARCH...39

5.2 APPLICATIONS TO COMPLEXITY THEORY....40

5.3 THE METHOD.....40


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5.4 COMPARISON OF BINARY SEARCH AND LINEAR SEARCH.43

CHAPTER 6 CONCLUSION.....46

6.1 FINAL SEARCH TIME AND EFFICIENCY.....46

6.2 APPLICATION OF ELECTRONIC DICTIONARY...46

APPENDIX A: LIST OF WORDS INCLUDED IN THE DICTIONARY. 47

APPENDIX B: PROGRAMMING CODES..55

APPENDIX C: SOFTWARES USED77

REFERENCES78

LIST OF FIGURES

1. FIGURE 1.1


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Pin Configuration Of Atmega32L

1. FIGURE 2.1

Cross Section Of a Simple LC Display

1. FIGURE 2.2

X,Y,Z Direction in LCD

1. FIGURE 2.3

Circuit for interfacing of LCD with ATMEGA 32L

1. FIGURE 3.1

Conceptual Matrix Circuit

1. FIGURE 3.2

Open Switch Key

1. FIGURE 3.3

Scanning Column 1

1. FIGURE 3.4

The A key is Pressed

1. FIGURE 3.5

The A Switch is Closed

1. FIGURE 3.6

Row 1 is Activated

1. FIGURE 3.7

Neither row is Activated

1. FIGURE 3.8

The Key A and D are pressed

1. FIGURE 3.9

Row 1 is Activated

1. FIGURE 3.10

Self The Key A,B and D are Pressed

1. FIGURE 3.11

Interface between Atmega32L and keyboard matrix

1. FIGURE 4.1

Circuit diagram Interfacing of two Atmega32L

1. FIGURE 4.2

Circuit Diagram Of Electronic Dictionary

1. FIGURE 5.1


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Flow Chart Of Binary Search Algorithm

LIST OF TABLES

1. TABLE 2.1

MECHANICAL SPECIFICATION OF LCD

1. TABLE 2.2

ELECTRICAL SPECIFICATION OF LCD

1. TABLE 2.3

PIN FUNCTIONS OF 16X2 LCD


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1. TABLE 3.1

LIST OF CODE ASSIGNED TO ALPHABETS

CHAPTER 1

INTRODUCTION

1.1 Introduction to Microcontrollers


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A microcontroller is a small computer on a single integrated circuit consisting of a

relatively simple CPU combined with support functions such as a crystal oscillator, timers,

watchdog, serial and analog I/O etc. Program memory in the form offlash orROM is also

often included on chip, as well as a, typically small, read/write memory.

Microcontrollers are designed for small applications. Thus, in contrast to the

microprocessors used inpersonal computers and other high-performance applications,

simplicity is emphasized. Some microcontrollers may operate at clock frequencies as low

as 32KHz, as this is adequate for many typical applications, enabling low power

consumption (milliwatts or microwatts). They will generally have the ability to retain

functionality while waiting for an event such as a button press or other interrupt; power

consumption while sleeping (CPU clock and most peripherals off) may be just nanowatts,

making many of them well suited for long lasting battery applications.

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

automobile engine control systems, 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.

The majority of computer systems in use today are embedded in other machinery, such as

automobiles, telephones, appliances, and peripherals for computer systems. These are

calledembedded systems. While some embedded systems are very sophisticated, many

have minimal requirements for memory and program length, with no operating system,

and low software complexity. Typical input and output devices include switches,relays,

solenoids, LEDs, small or custom LCD displays, radio frequency devices, and sensors for

data such as temperature, humidity, light level etc. Embedded systems usually have no

keyboard, screen, disks, printers, or other recognizable I/O devices of apersonal computer,

and may lack human interaction devices of any kind.

Since embedded processors are usually used to control devices, they sometimes need to

accept input from the device they are controlling. This is the purpose of the analog to

digital converter. Since processors are built to interpret and process digital data, i.e. 1s and

0s, they won't be able to do anything with the analog signals that may be being sent to itby a device. So the analog to digital converteris used to convert the incoming data into a
http://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Crystal_oscillatorhttp://en.wikipedia.org/wiki/Watchdog_timerhttp://en.wikipedia.org/wiki/NOR_flashhttp://en.wikipedia.org/wiki/ROMhttp://en.wikipedia.org/wiki/Microprocessorhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Embedded_systemhttp://en.wikipedia.org/wiki/Embedded_systemhttp://en.wikipedia.org/wiki/Relayhttp://en.wikipedia.org/wiki/Relayhttp://en.wikipedia.org/wiki/Solenoidhttp://en.wikipedia.org/wiki/LEDhttp://en.wikipedia.org/wiki/LEDhttp://en.wikipedia.org/wiki/LCDhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Analog_to_digital_converterhttp://en.wikipedia.org/wiki/Analog_to_digital_converterhttp://en.wikipedia.org/wiki/Analog_to_digital_converterhttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Crystal_oscillatorhttp://en.wikipedia.org/wiki/Watchdog_timerhttp://en.wikipedia.org/wiki/NOR_flashhttp://en.wikipedia.org/wiki/ROMhttp://en.wikipedia.org/wiki/Microprocessorhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Embedded_systemhttp://en.wikipedia.org/wiki/Relayhttp://en.wikipedia.org/wiki/Solenoidhttp://en.wikipedia.org/wiki/LEDhttp://en.wikipedia.org/wiki/LCDhttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Analog_to_digital_converterhttp://en.wikipedia.org/wiki/Analog_to_digital_converterhttp://en.wikipedia.org/wiki/Analog_to_digital_converter


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form that the processor can recognize. There is also a digital to analog converterthat

allows the processor to send data to the device it is controlling.

In addition to the converters, many embedded microprocessors include a variety of timers

as well. One of the most common types of timers is theProgrammable Interval Timer, or

PIT for short. A PIT just counts down from some value to zero. Once it reaches zero, it

sends an interrupt to the processor indicating that it has finished counting. This is useful

for devices such as thermostats, which periodically test the temperature around them to see

if they need to turn the air conditioner on, the heater on, etc.

Time Processing Unit or TPU for short is a sophisticated timer. In addition to counting

down, the TPU can detect input events, generate output events, and perform other useful

operations.

DedicatedPulse Width Modulation (PWM) block makes it possible for the CPU to control

power converters, resistive loads, motors, etc., without using lots of CPU resources in tight

timerloops.

Universal Asynchronous Receiver/Transmitter(UART) block makes it possible to receive

and transmit data over a serial line with very little load on the CPU.

In contrast to general-purpose CPUs, microcontrollers may not implement an external

address or data bus as they integrate RAM and non-volatile memory on the same chip as

the CPU. Using fewer pins, the chip can be placed in a much smaller, cheaper package.

Integrating the memory and other peripherals on a single chip and testing them as a unit

increases the cost of that chip, but often results in decreased net cost of the embedded

system as a whole. Even if the cost of a CPU that has integrated peripherals is slightly

more than the cost of a CPU + external peripherals, having fewer chips typically allows a

smaller and cheaper circuit board, and reduces the labor required to assemble and test the

circuit board.

A microcontroller is a single integrated circuit, commonly with the following features:

central processing unit - ranging from small and simple 4-bit processors to

complex 32- or 64-bit processors

discrete input and output bits, allowing control or detection of the logic state of an

individual package pin

serial input/output such as serial ports (UARTs)
http://en.wikipedia.org/wiki/Digital_to_analog_converterhttp://en.wikipedia.org/wiki/Programmable_Interval_Timerhttp://en.wikipedia.org/wiki/Programmable_Interval_Timerhttp://en.wikipedia.org/wiki/Time_Processor_Unithttp://en.wikipedia.org/wiki/Pulse-width_modulationhttp://en.wikipedia.org/wiki/Pulse-width_modulationhttp://en.wikipedia.org/wiki/Switched-mode_power_supplyhttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Universal_asynchronous_receiver/transmitterhttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Input/outputhttp://en.wikipedia.org/wiki/Serial_porthttp://en.wikipedia.org/wiki/UARThttp://en.wikipedia.org/wiki/Digital_to_analog_converterhttp://en.wikipedia.org/wiki/Programmable_Interval_Timerhttp://en.wikipedia.org/wiki/Time_Processor_Unithttp://en.wikipedia.org/wiki/Pulse-width_modulationhttp://en.wikipedia.org/wiki/Switched-mode_power_supplyhttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Universal_asynchronous_receiver/transmitterhttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Input/outputhttp://en.wikipedia.org/wiki/Serial_porthttp://en.wikipedia.org/wiki/UART


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otherserial communicationsinterfaces like IC, Serial Peripheral Interface and

Controller Area Networkfor system interconnect

peripherals such as timers, event counters, PWM generators, and watchdog

volatile memory (RAM) for data storage

ROM, EPROM, EEPROM orFlash memory forprogram and operating parameter

storage

clock generator- often an oscillator for a quartz timing crystal, resonator orRC

circuit

many include analog-to-digital converters

in-circuit programming and debugging support

This integration drastically reduces the number of chips and the amount of wiring and

circuit board space that would be needed to produce equivalent systems using separate

chips. Furthermore, and on low pin count devices in particular, each pin may interface to

several internal peripherals, with the pin function selected by software. This allows a part

to be used in a wider variety of applications than if pins had dedicated functions.

Microcontrollers have proved to be highly popular in embedded systems since theirintroduction in the 1970s.

Some microcontrollers use a Harvard architecture: separate memory buses for instructions

and data, allowing accesses to take place concurrently. Where a Harvard architecture is

used, instruction words for the processor may be a different bit size than the length of

internal memory and registers; for example: 12-bit instructions used with 8-bit data

registers.

The decision of which peripheral to integrate is often difficult. The microcontrollervendors often trade operating frequencies and system design flexibility against time-to-

market requirements from their customers and overall lower system cost. Manufacturers

have to balance the need to minimize the chip size against additional functionality.

Microcontroller architectures vary widely. Some designs include general-purpose

microprocessor cores, with one or more ROM, RAM, or I/O functions integrated onto the

package. Other designs are purpose built for control applications. A microcontroller

instruction set usually has many instructions intended for bit-wise operations to make

control programs more compact.[2] For example, a general purpose processor might require

several instructions to test a bit in a register and branch if the bit is set, where a
http://en.wikipedia.org/wiki/Serial_communicationshttp://en.wikipedia.org/wiki/Network_interfacehttp://en.wikipedia.org/wiki/I%C2%B2Chttp://en.wikipedia.org/wiki/Serial_Peripheral_Interfacehttp://en.wikipedia.org/wiki/Controller_Area_Networkhttp://en.wikipedia.org/wiki/Peripheralhttp://en.wikipedia.org/wiki/Timerhttp://en.wikipedia.org/wiki/Pulse-width_modulationhttp://en.wikipedia.org/wiki/Watchdog_timerhttp://en.wikipedia.org/wiki/RAMhttp://en.wikipedia.org/wiki/Read-only_memoryhttp://en.wikipedia.org/wiki/EPROMhttp://en.wikipedia.org/wiki/EEPROMhttp://en.wikipedia.org/wiki/Flash_memoryhttp://en.wikipedia.org/wiki/Computer_programhttp://en.wikipedia.org/wiki/Clock_generatorhttp://en.wikipedia.org/wiki/RC_circuithttp://en.wikipedia.org/wiki/RC_circuithttp://en.wikipedia.org/wiki/Analog_to_digital_converterhttp://en.wikipedia.org/wiki/Printed_circuit_boardhttp://en.wikipedia.org/wiki/Embedded_systemhttp://en.wikipedia.org/wiki/Harvard_architecturehttp://en.wikipedia.org/wiki/Serial_communicationshttp://en.wikipedia.org/wiki/Network_interfacehttp://en.wikipedia.org/wiki/I%C2%B2Chttp://en.wikipedia.org/wiki/Serial_Peripheral_Interfacehttp://en.wikipedia.org/wiki/Controller_Area_Networkhttp://en.wikipedia.org/wiki/Peripheralhttp://en.wikipedia.org/wiki/Timerhttp://en.wikipedia.org/wiki/Pulse-width_modulationhttp://en.wikipedia.org/wiki/Watchdog_timerhttp://en.wikipedia.org/wiki/RAMhttp://en.wikipedia.org/wiki/Read-only_memoryhttp://en.wikipedia.org/wiki/EPROMhttp://en.wikipedia.org/wiki/EEPROMhttp://en.wikipedia.org/wiki/Flash_memoryhttp://en.wikipedia.org/wiki/Computer_programhttp://en.wikipedia.org/wiki/Clock_generatorhttp://en.wikipedia.org/wiki/RC_circuithttp://en.wikipedia.org/wiki/RC_circuithttp://en.wikipedia.org/wiki/Analog_to_digital_converterhttp://en.wikipedia.org/wiki/Printed_circuit_boardhttp://en.wikipedia.org/wiki/Embedded_systemhttp://en.wikipedia.org/wiki/Harvard_architecture


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microcontroller could have a single instruction to provide that commonly-required

function.

Microcontrollers typically do not have a math coprocessor, so fixed point orfloating point

arithmetic are performed by program code.

Microcontrollers were originally programmed only inassembly language, but various

high-level programming languages are now also in common use to target microcontrollers.

These languages are either designed specially for the purpose, or versions of general

purpose languages such as theC programming language. Compilers for general purpose

languages will typically have some restrictions as well as enhancements to better support

the unique characteristics of microcontrollers. Some microcontrollers have environments

to aid developing certain types of applications. Microcontroller vendors often make tools

freely available to make it easier to adopt their hardware.

1.2 FEATURES AND FUNCTIONS OF ATMEGA 32L

Features

Advanced RISC Architecture

131 Powerful Instructions Most Single-clock Cycle Execution

32 x 8 General Purpose Working Registers

Fully Static Operation

Up to 16 MIPS Throughput at 16 MHz

On-chip 2-cycle Multiplier

High Endurance Non-volatile Memory segments

32K Bytes of In-System Self-programmable Flash program memory

1024 Bytes EEPROM

2K Byte Internal SRAM

Write/Erase Cycles: 10,000 Flash/100,000 EEPROM

Data retention: 20 years at 85C/100 years at 25C

Optional Boot Code Section with Independent Lock Bits

In-System Programming by On-chip Boot Program

True Read-While-Write Operation Programming Lock for Software Security

JTAG (IEEE std. 1149.1 Compliant) Interface
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Boundary-scan Capabilities According to the JTAG Standard

Extensive On-chip Debug Support

Programming of Flash, EEPROM, Fuses, and Lock Bits through the JTAG Interface

Peripheral Features

Two 8-bit Timer/Counters with Separate Prescalers and Compare Modes

One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and Capture

Mode

Real Time Counter with Separate Oscillator

Four PWM Channels

8-channel, 10-bit ADC

8 Single-ended Channels

7 Differential Channels in TQFP Package Only

2 Differential Channels with Programmable Gain at 1x, 10x, or 200x

Byte-oriented Two-wire Serial Interface

Programmable Serial USART

Master/Slave SPI Serial Interface

Programmable Watchdog Timer with Separate On-chip Oscillator

On-chip Analog Comparator

Special Microcontroller Features

Power-on Reset and Programmable Brown-out Detection

Internal Calibrated RC Oscillator

External and Internal Interrupt Sources

Six Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, Standby

and Extended Standby

I/O and Packages

32 Programmable I/O Lines

40-pin PDIP, 44-lead TQFP, and 44-pad QFN/MLF

Operating Voltages

2.7 - 5.5V for ATmega32L

4.5 - 5.5V for ATmega32

Speed Grades

0 - 8 MHz for ATmega32L

0 - 16 MHz for ATmega32

Power Consumption at 1 MHz, 3V, 25C for ATmega32L


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Active: 1.1 mA

Idle Mode: 0.35 mA

Power-down Mode: < 1 A

Memory

The AVR architecture has two main memory spaces, the Data Memory and the Program

Memory space. In addition, the ATmega32 features an EEPROM Memory for data

storage. All three memory spaces are linear and regular.

The ATmega32 contains 32K bytes On-chip In-System Reprogrammable Flash memory

for program

storage. Since all AVR instructions are 16 or 32 bits wide, the Flash is organized as 16K x

16. For software security, the Flash Program memory space is divided into two sections,

Boot

Program section and Application Program section.

The Flash memory has an endurance of at least 10,000 write/erase cycles. The ATmega32

Program

Counter (PC) is 14 bits wide, thus addressing the 16K program memory locations.

The lower 2144 Data Memory locations address the Register File, the I/O Memory, and

the internal

data SRAM. The first 96 locations address the Register File and I/O Memory, and the next

2048 locations address the internal data SRAM.

The five different addressing modes for the data memory cover: Direct, Indirect with

Displacement,Indirect, Indirect with Pre-decrement, and Indirect with Post-increment. In the Register

File, registers R26 to R31 feature the indirect Addressing Pointer Registers.

The direct addressing reaches the entire data space.

The Indirect with Displacement mode reaches 63 address locations from the base address

given

by the Y- or Z-register.

When using register indirect addressing modes with automatic pre-decrement and post-

increment,

the address registers X, Y, and Z are decremented or incremented.


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The 32 general purpose working registers, 64 I/O Registers, and the 2048 bytes of internal

data

SRAM in the ATmega32 are all accessible through all these addressing modes.

1.3 PIN CONFIGURATION

The ATMEGA 32L has total forty pins. four ports named A,B,C and D having eight pins

each. Some of these pins are used for multiple purpose such as Analog to Digital

convertor, Interrupt handling and serial communication. These ports can have

unidirectional or bidirectional or both types of data transfers.

Atmega 32L comes in two types of packaging-DIP and TQFP. The packaging used for

electronic dictionary is DIP.


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Figure 1.1 : Pin Configuration of Atmega32L

CHAPTER 2

LCD AND ITS INTERFACING

2.1 Working Principle of LCD

2.1.0 Liquid Crystal Display Fundamentals

LCD Modules can present textual information to user. Its like a cheap monitor that you can

hook in all of your gadgets. They come in various types. The most popular one can display 2 lines


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of 16 characters. These can be easily interfaced to MCU's, thanks to the API( Functions used to

easily access the modules) we provide.

2.1.1 General Characteristics and LCD Modes

Liquid Crystal Displays (LCDs) are categorized as non- emissive display devices, in that

respect, they do not produce any form of light like a Cathode Ray Tube (CRT). LCDs

either pass or block light that is reflected from an external light source or provided by a

back/side lighting system. There are two modes of operation for LCDs during the absence

of an electric field (applied Power); a mode describes the transmittance state of the liquid

crystal elements. Normal White mode: the display is white or clear and allows light to pass

through and Normal Black Mode: the display is dark and all light is diffused. Virtually alldisplays in production for PC/Workstation use are normal white mode to optimize contrast

and speed.

2.1.2 LCD Cell Switching and Fundamentals

A simplified description of how a dot matrix LCD display works is as follows: A twisted

nematic (TN) LC display consists of two polarizers, two pieces of glass, some form of

switching element or electrode to define pixels, and driver Integrated Circuits (ICs) to

address the rows and columns of pixels. To define a pixel (or subpixel element for a colordisplay), a rectangle is constructed out of Indium Tin Oxide -- a semi-transparent metal

oxide (ITO) and charge is applied to this area in order to change the orientation of the LC

material ( change from a white pixel to a dark pixel). The method utilized to form a pixel

in passive and active matrix displays differs and will be described in later sections. Figure

1 illustrates a cross sectional view of a simple TN LC display. Figure 2 depicts a dot

matrix display as viewed without its metal module/case exposing the IC drivers. Looking

directly at the display the gate or row drivers are located either on the left or the right side

of the display while the data or column drivers are located on the top (and or bottom) of

the display. New thin display module technology mounts the ICs on conductive tape that

allows them to be folded behind the display further reducing the size of the finished

module. An IC will address a number of rows or columns, not just 1 as pictured in figure

2.1


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Figure 2.1 : Cross Section of a Simple LC Display

Polarizers are an integral part of a LCD display, possessing the unique property of only

passing light if it is oriented in a specific (oriented) direction. To utilize this phenomena in

TN LC displays, the bottom polarizer orients incoming light in one direction. The oriented

light passes through the LC material and is either unaltered or "bent" 90 degrees.

Depending on the orientation of the top polarizer, this light will either pass through or be

diffused. If the light is diffused, it will appear as a dark area. Figure 3 is a simple

illustration of the sequence of events that occur when light passes through a simple twistednematic LC display.

2.2 Liquid Crystal Material

Liquid crystals encompass a broad group of materials that posses the properties of both a

solid and a liquid. More specifically, they are a liquid with molecules oriented in onecommon direction (having a long range and repeating pattern-- definition of a crystal), but


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have no long range order in the other two directions. For example, in figure 4 all the lines

are oriented in the Y direction (up and down), but they posses no common ordering in the

x direction (disorder is assumed in the Z direction). To more easily visualize this, think of

figure 4 as one thin slice (one layer of molecules to be exact) of a block of material. If you

examined another slice, the molecules would still be oriented in the Y direction, but they

would be in different positions along the X-axis. By stacking millions of these thin slices,

the Z direction is built up and as a result of the change in relative position on the x-axis,

the Z direction has no long range order.

Figure 2.2 : X,Y,Z-Direction in LCD.

The liquid crystals used for display technology are thermotropic liquid crystals; they

exhibit desired characteristics over a specific temperature range. This is the primary reason

why LCDs do not operate properly when they are too cold or too warm. If liquid crystals

are too cold, they will not twist and the display will not form an image. If the display is

too warm, the resistance of the liquid crystal material changes and this alters the properties

of the display and performance suffers. Liquid crystal material for display use is normally

referred to as TN (STN, DSTN, MSTN, and etc.) or Twisted Nematic--sometimes known

as TNFE or Twisted Nematic Field Effect. It is called TWISTED since the crystals are

twisted 90 degrees (or more for STN) from the top piece of glass to the bottom piece of

glass. (TN usually refers only to a 90 degree twist.) Field Effect (a direct correlation is the

semiconductor MOSFET), refers to the LC material's ability to align parallel or

perpendicular to an applied electric field. As a result, using twisted or untwisted liquid

crystal and two polarizers; an applied electric field can force the LC material into a

particular alignment effectively diffusing or passing light through the top polarizer.


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As a note of interest, polarizers are also one of the major reasons that LC displays require

bright back lighting. The polarizers and liquid crystal materials absorb more than 50% of

the incident light. As a result, even though the actual display is a very low power device,

the power hungry back lighting makes a LCD module one of the primary causes of short

battery life in notebook computers. Due to the fact that the LC material has optical

properties and effectively bends light, the problem of viewing angle effects occur. When

the user is not directly in front of the display the image can disappear or seem to invert

(dark images become light and light images become dark). However, LC material and

polarizer technology is rapidly improving and that improvement is showing up in brighter

displays with greater viewing angles.

2.2.1 Liquid Crystal Alignment

Liquid crystals must be aligned to the top and bottom pieces of glass in order to obtain the

desired twist. In other words, the 90 degree twist is formed by anchoring the liquid crystal

on one glass plate and forcing it to twist across the cell gap (the distance between the two

glass plates) when contacting the second plate. Furthermore, The actual image quality of

the display will be dependent on the surface alignment of the LC material. The method

currently used for aligning liquid crystals was developed by the Dai-Nippon Screening

(English= Big Japan Screening) Company. The process consists of coating the top and

bottom sheets of glass with a Polyimide based film. The top piece of glass is coated and

rubbed in a particular orientation; the bottom panel/polyimide is rubbed perpendicular (90

degrees for TN displays) with respect to the top panel. It was discovered that by rubbing

the polyimide with a cloth, nanometer (1 X 10 - 9 meters) size grooves are formed and the

liquid crystals align with the direction of the grooves. It is common that when assembling

a TN LC cell, it will be necessary to eliminate patches of non- uniform areas. The two

parameters required to eliminate the nonuniformities and complete the TN LC display are

pretilt angle and cholesteric impurities. TN LC cells commonly have two problems that

affect uniformity following assembly: reverse tilt and reverse twist. Reverse tilt is a

function of the applied electrical field and reverse twist is common when no electrical

field is applied. Reverse twist is eliminated by the introduction of cholesteric additives and

reverse tilt is eliminated by introducing a pre-tilt angle to the LC material. The pre-tilt

angle also determines what direction the LC molecules will rotate when an electrical field

is applied. Pre-tilt angle can be visualized by considering the normal position of the LC

molecule to be flat against the glass plate, by anchoring one edge and forcing the other

upward by a specific number of degrees, a pretilt angle is established.


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2.3 FEATURES AND SPECIFICATIONS OF 16X2 LCD

2.3.1 FEATURES

5 x 8 dots with cursor

Built-in controller (KS 0066 or Equivalent)

+ 5V power supply (Also available for + 3V)

1/16 duty cycle

B/L to be driven by pin 1, pin 2 or pin 15, pin 16 or A.K (LED)

N.V. optional for + 3V power supply

2.3.2 MECHANICAL AND ELECTRICAL SPECIFICATIONS

Table 2.1 : Mechanical Specification Of LCD


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Table 2.2 : Electrical Specification Of LCD

2.3.3 PIN FUNCTIONS OF 16X2 LCD


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Table 2.3 : Pin Functions Of 16X2 LCD


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2.4 INTERFACING OF LCD WITH MICROCONTROLLER

For electronic dictionary, four pins of the LCD are used for data transfer and display

which are connected to PORT C of the microcontroller. Two pins are used for Vcc and

GND and one pin is connected to a 10K ohm potentiometer for contrast adjustment.

The code for sending data to the LCD data bus is given in Appendix 2.

Figure 2.3: Circuit for interfacing of LCD with ATMEGA 32L

CHAPTER 3


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MATRIX KEYBOARD AND ITS INETRFACING

3.1 The Matrix Circuit

Keyboards use a matrix with the rows and columns made up of wires. Each key acts like a

switch. When a key is pressed, a column wire makes contact with a row wire and

completes a circuit. The keyboard controller detects this closed circuit and registers it as a

key press. Here is a simple keyboard matrix:

Figure 3.1 : Conceptual Matrix Circuit

This keyboard only has 4 keys: A, B, C, and D. Each key has a unique grid location, much

like points on a graph. Key A is at node C1R1, key B is at node C2R1, key Cis at node

C1R2, and key D is at node C2R2. In reality this is pretty useless which is why real

keyboards use many more rows and columns. The electronic circuit for this matrix looks

something (not exactly) like this:


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Then it activates column C2 and checks rows R1 and R2 again:

Neither keyB norD are pressed so neither row R1 nor R2 is activated. The controller now

knows that both nodes C2R2 and C2R2 are deactivated.

3.2.1 Single Key Presses

Now, let's say the the A key is pressed. The matrix will look like this:

Figure 3.4 The A Key is Pressed

Key A corresponds to node C1R1. By going back to the circuit, we can see how C1R1 is

detected. First, here is the circuit with switch A closed:

Figure 3.5 The A Switch is Closed

Walking through the scanning procedure again, the controller activates column C1 and

detects which rows are activated:


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Figure 3.6 Row 1 is Activated

This time, row R1 is activated. So the controller now knows that node C1R1 is pressed.

Since C1R1 corresponds to the A key, the controller knows that the A key is pressed.

When the controller activates column C2, neither row R1 nor R2 are activated. Both

switches B and D are open:

Figure 3.7 Neither Row is Activated

When the A key is released, the circuit goes back to the original, and the controller detects

the node C1R1 is no longer activated.

3.2.2 Multiple Key Presses

Now we will cover multiple key presses. Let's say that both keys AandD are pressed at

the same time. The matrix will look like this:


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Figure 3.8 The A and D Keys are Pressed

Both nodes C1R1 and C2R2 should be detected. Here is the circuit with both switches Aand D closed:

Scanning column C1 then column C2 produces an outcome like this:

Figure 3.9 Row 1 is Activated

When column C1 is activated, row R1 is active, hence node C1R1 is activated. When

column C2 is activated, row R2 is activated, hence node C2R2 is activated.

3.2.3 Three Simultaneous Key Presses and Ghosting

When three keys are pressed at the same time, ghosting may occur. In this example, keys

A, B, and D are pressed. The matrix looks like this:


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Figure 3.10 The A, B, and D Keys are Pressed

If everything goes well, nodes C1R1, C2R1, and C2R2 will be detected. Let's look at thecircuit

If you get the feeling something is not right, you are correct! This is where the ghosting

problem comes to play. Row R1 is activated as well as row R2, so both nodes C1R1 and

C1R2 are activated. Node C1R1 is expected as it corresponds to the A key that is pressed.

However, node C1R2 corresponds to the Ckey. Switch C is open, so the key is not really

pressed. The keyboard controller does not know this and incorrectly generates a Ckey

press.

What happens is that closing switch B and switch D at the same time creates an electrical

path from C1 to R2, bypassing the open switch C. The keyboard does not know that

switch Cis open and generates a "ghost" key press. Ghosting will show up when any 3

corners of a rectangle in the matrix are pressed at once. In my simple example, any 3 keys

causes ghosting, but in a bigger matrix only 3 corners of a rectangle cause it.

Just for completion, here is the circuit when activating column C2:

As expected, nodes C2R1 and C2R2 are activated corresponding to the B and D keys

3.3 Interfacing 4X4 Matrix Keypad with Atmega 32L


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Figure 3.11 : Interface between Atmega32L and keyboard matrix

The four input pin has a 10k pull-up to Vcc. We make the upper four bits of PortD

function as output with a logic high. The lower four bits are made to funtion as input with

a logic low. Now, if a key is pressed, a connection is made between a column (output,

logic low) and a row (input, logic high). This row line will be pulled low. Also, the OR

output goes low, and Int0 fires an interrupt.

In the interrupt routine we quickly read the state of the row lines to see on which row the

pressed key is. Then, the upper four bits of PortD are made input with logic level high, and

the lower four bits are made output with logic level low. Now, we read the state of the


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upper four bits to determine on which column the pressed key is. We then wait a certain

'debounce' time. From the state of the row and column lines read, the key pressed is

determined. Lastly, the state of the row and column bits of Port D is restored to the

starting point.Which key has been pressed is then determined from the state of the row and

column bits.The first 13 keys are dual function keys representing two consecutive

alphabets with the use of a shift key. Suppose we have to enter alphabet B. For that we

will press alphabet A along with shift key. The last three keys in the matrix are not dual

functions. They are used for BACKSPACE, SEARCH and RESET instructions. Following

is the table for assigning a specific code to an alphabet or an instruction:

Code generated Alphabet Assigned

1 A

2 B

3 C

4 D

5 E

6 F

7 G

8 H

9 I

10 J

11 K

12 L

13 M

14 N

15 O

16 P

17 Q

18 R

19 S

20 T


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21 U

22 V

23 W

24 X

25 Y

26 Z

27 BACKSPACE

28 SEARCH

29 RESET

Table 3.1 : List of Code assigned to alphabets

CHAPTER 4

COMPLETE CIRCUIT INTERFACING

4.1 Interfacing of two atmega32


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Figure 4.1 Circuit Diagram Interfacing of two Atmega32L

4.1.1 USART Initialization

The USART has to be initialized before any communication can take place. The

initialization process

normally consists of setting the baud rate, setting frame format and enabling the

Transmitter or the Receiver depending on the usage. For interrupt driven USART

operation, the

Global Interrupt Flag should be cleared (and interrupts globally disabled) when doing the

initialization.


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Before doing a re-initialization with changed baud rate or frame format, be sure that there

are no

ongoing transmissions during the period the registers are changed. The TXC Flag can be

used

to check that the Transmitter has completed all transfers, and the RXC Flag can be used to

check that there are no unread data in the receive buffer. Note that the TXC Flag must be

cleared before each transmission (before UDR is written) if it is used for this purpose.

4.1.2 Data Transmission The USART Transmitter

The USART Transmitter is enabled by setting the Transmit Enable (TXEN) bit in the

UCSRB Register. When the Transmitter is enabled, the normal port operation of the TxD

pin is overridden by the USART and given the function as the transmitters serial output.

The baud rate, mode of operation and frame format must be set up once before doing any

transmissions. If synchronous operation is used, the clock on the XCK pin will be

overridden and used as transmission clock.

4.1.2 Data Transmission The USART Receiver

The USART Receiver is enabled by writing the Receive Enable (RXEN) bit in the

UCSRB Register to one. When the receiver is enabled, the normal pin operation of the

RxD pin is overridden by the USART and given the function as the receivers serial input.

The baud rate, mode of operation and frame format must be set up once before any serial

reception can be done. If synchronous operation is used, the clock on the XCK pin will be

used as transfer clock.

For the code refer to appendix.

4.2 Circuit Diagram of Electronic Dictionary


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Figure 4.2 Circuit Diagram of Electronic Dictionary

CHAPTER 5


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SEARCHING ALGORITHIM

5.1 Binary Search

Finding the index of a specific value in a sorted list is useful because, given the index,

other data structures will contain associated information. Suppose a data structure

containing the classic collection of name, address, telephone number and so forth has been

accumulated, and an array is prepared containing the names, numbered from one to N. A

query might be: what is the telephone number for a given name X. To answer this the

array would be searched and the index (if any) corresponding to that name determined,

whereupon the associated telephone number array would have X's telephone number at

that index, and likewise the address array and so forth.

If the list of names is in sorted order, a binary search will find a given name with far fewer

probes than the simple procedure of probing each name in the list, one after the other in a

linear search, and the procedure is much simpler than organizing a hash table. However,

once created, searching with a hash table may well be faster, typically averaging just over

one probe per lookup. With a non-uniform distribution of values, if it is known that some

few items are much more likely to be sought for than the majority, then a linear search

with the list ordered so that the most popular items are first may do better than binary

search. The choice of the best method may not be immediately obvious. If, between

searches, items in the list are modified or items are added or removed, maintaining the

required organisation may consume more time than the searches.

5.2 Applications to complexity theory

Even if we do not know a fixed range the number k falls in, we can still determine its

value by asking simple yes/no questions of the form "Is k greater than x?" for
http://en.wikipedia.org/wiki/Sorting_algorithmhttp://en.wikipedia.org/wiki/Linear_searchhttp://en.wikipedia.org/wiki/Hash_tablehttp://en.wikipedia.org/wiki/Computational_complexity_theoryhttp://en.wikipedia.org/wiki/Sorting_algorithmhttp://en.wikipedia.org/wiki/Linear_searchhttp://en.wikipedia.org/wiki/Hash_tablehttp://en.wikipedia.org/wiki/Computational_complexity_theory


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some number x. As a simple consequence of this, if you can answer the question "Is this

integer property k greater than a given value?" in some amount of time then you can find

the value of that property in the same amount of time with an added factor of log 2k. This is

called a reduction, and it is because of this kind of reduction that most complexity

theorists concentrate on decision problems, algorithms that produce a simple yes/no

answer.For example, suppose we could answer "Does this n x n matrix have determinant

larger than k?" in O(n2) time. Then, by using binary search, we could find the (ceiling of

the) determinant itself in O(n2log d) time, where d is the determinant; notice that d is not

the size of the input, but the size of the output.

5.3 The method

In order to discuss the method in detail, a more formal description is necessary. The basic

idea is that there is a data structure represented by array A in which individual elements

are identified as A(1), A(2),,A(N) and may be accessed in any order. The data structure

contains a sub-element or data field called here Key, and the array is ordered so that the

successive values A(1).Key A(2).Key and so on. The requirement is that given some

value x, find an index p (not necessarily the one and only) such that A(p).Key = x.

To begin with, the span to be searched is the full supplied list of elements, as marked by

variables L and R, and their values are changed with each iteration of the search process,

as depicted by the flowchart. Note that the division by two is integer division, with any

remainder lost, so that 3/2 comes out as 1, not 1. The search finishes either because the

value has been found, or else, the specified value is not in the list.
http://en.wikipedia.org/wiki/Reduction_(complexity)http://en.wikipedia.org/wiki/Decision_problemhttp://en.wikipedia.org/wiki/Determinanthttp://en.wikipedia.org/wiki/Flowcharthttp://en.wikipedia.org/wiki/Reduction_(complexity)http://en.wikipedia.org/wiki/Decision_problemhttp://en.wikipedia.org/wiki/Determinanthttp://en.wikipedia.org/wiki/Flowchart


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Figure 5.1 : Flow Chart of Binary Search algorithm

5.3.1 Working

The method relies on and upholds the notion If x is to be found, it will be amongst

elements (L + 1) to (R 1) of the array.

The initialisation of L and R to 0 and N + 1 make this merely a restatement of the supplied

problem, that elements 1 to N are to be searched, so the notion is established to begin with.

The first step of each iteration is to check that there is something to search, which is to say

whether there are any elements in the search span (L + 1) to (R 1). The number of such

elements is (R L 1) so computing (R L) gives (number of elements + 1); halving that

number (with integer division) means that if there was one element (or more) then p = 1
http://en.wikipedia.org/wiki/Invariant_(computer_science)http://en.wikipedia.org/wiki/Invariant_(computer_science)http://en.wikipedia.org/wiki/Invariant_(computer_science)http://en.wikipedia.org/wiki/Invariant_(computer_science)


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(or more), but if none p = 0, and in that case the method terminates with the report "Not

found". Otherwise, for p > 0, the search continues with p:=L + p, which by construction is

within the bounds (L + 1) to (R 1). That this position is at or adjacent to the middle of

the span is not important here, merely that it is a valid choice.

Now compare x to A(p).Key. If x = A(p).Key then the method terminates in success.

Otherwise, suppose x < A(p).Key. If so, then because the array is in sorted order, x will

also be less than all later elements of the array, all the way to element (R 1) as well.

Accordingly, the value of the right-hand bound index R can be changed to be the value p,

since, by the test just made, x < A(p).Key and so, if x is to be found, it will be amongst

elements earlier than p, that is (p 1) and earlier. And contrariwise, for the case x >A(p).Key, the value of L would be changed. Thus, whichever bound is changed the ruling

notion is upheld, and further, the span remaining to be searched is reduced. If L is

changed, it is changed to a higher number (at least L + 1), whereas if R is changed, it is to

a lower number (at most R 1) because those are the limits for p.

Should there have been just one value remaining in the search span (so that L + 1 = p = R

1), and x did not match, then depending on the sign of the comparison either L or R will

receive the value of p and at the start of the next iteration the span will be found to be

empty.

Accordingly, with each iteration, if the search span is empty the result is "Not found",

otherwise either x is found at the probe point p or the search span is reduced for the next

iteration. Thus the method works, and so can be called an Algorithm.

5.3.2 Speed

After each iteration, the span left to be searched is roughly [vague] halved. If the original

number of items is N = 2p, then after the first iteration there will be roughly 2p-1 items

remaining, then roughly 2p-2, and so on. In the worst case, the algorithm must continue

iterating until the span has been reduced to a single item, i.e. 20; this will have taken p =

log2(N) iterations. When compared to the linear search, whose worst-case behaviour is N

iterations, we see that the binary search is substantially faster as N grows large.

In most cases, N will not be an integer power of 2. In these cases, the worst-case iteration

count will be ceil(log2(N)), where ceil() denotes the ceiling function.
http://en.wikipedia.org/wiki/Algorithmhttp://en.wikipedia.org/wiki/Binary_logarithmhttp://en.wikipedia.org/wiki/Binary_logarithmhttp://en.wikipedia.org/wiki/Linear_searchhttp://en.wikipedia.org/wiki/Ceiling_functionhttp://en.wikipedia.org/wiki/Algorithmhttp://en.wikipedia.org/wiki/Binary_logarithmhttp://en.wikipedia.org/wiki/Linear_searchhttp://en.wikipedia.org/wiki/Ceiling_function


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5.3.3 Average performance

There are two cases: for searches that will fail because the value is not in the list, the

search span must be successively halved until no more elements remain and this process

will require at most the p probes just defined, or one less. This latter occurs because the

search span is not in fact exactly halved, and depending on the value of N and which

elements of the list the absent value x is between, the span may be closed early.

For searches that will succeed because the value is in the list, the search may finish early

because a probed value happens to match. Loosely speaking, half the time the search will

finish one iteration short of the maximum and a quarter of the time, two early. Consider

then a test in which a list of N elements is searched once for each of the N values in the

list, and determine the number of probes n for all N searches.

5.4 Comparison of Binary Search and Linear Search

Linear Search operates by checking every element of a list one at a time in sequence until

a match is found. Linear search runs inO(n). If the data are distributed randomly, theexpected number of comparisons that will be necessary is:

where n is the number of elements in the list and k is the number of times that the value

being searched for appears in the list. The best case is that the value is equal to the first

element tested, in which case only 1 comparison is needed. The worst case is that the

value is not in the list (or it appears only once at the end of the list), in which case n

comparisons are needed

The simplicity of the linear search means that if just a few elements are to be searched it is

less trouble than more complex methods that require preparation such as sorting the list to

be searched or more complex data structures, especially when entries may be subject to

frequent revision. Another possibility is when certain values are much more likely to be

searched for than others and it can be arranged that such values will be amongst the firstconsidered in the list.
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The following pseudo code describes the linear search technique.

For each item in the list:

Check to see if the item you're looking for matches the item in the list.

If it matches.

Return the location where you found it (the index).

If it does not match.

Continue searching until you reach the end of the list.

If we get here, we know the item does not exist in the list. Return -1.

Whereas Binary Search uses less number of comparison to get the search done.

Linear Search:

Worst case performance -- (n)

Best case performance -- O(1)

Average case performance O(n/2)

Binary Search :

Worst case performance -- (log n)

Best case performance -- O(1)

Average case performance -- O(log n)

From above mentioned time complexity binary search is far more better than linear

search ,thus its being used in our searching module.


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CHAPTER 6

RESULT AND COMPARISONS

6.1 Final Search Time and Efficiency

The electronic dictionary searches any word in its database in less than 0.2 seconds.

There is no word meaning mismatch or any other errors in the dictionary.

Therefore the electronic dictionary is completely efficient.


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6.2 Application of Electronic Dictionary

Its main application is for candidates preparing for exams like GRE, GMAT, CAT .

It can be customized for any type of word list which can be helpful to tourists.

Can be used for developing a good vocabulary.

APPENDIX A: List of Words

Word Meaning

Abhor Detest

Abjure Renounce

Abnegate Give up

Abominable Bad

Abrogate Abolish

Abscission Separation

Absolve Pardon

Abysmal Dismal

Accede Proposal

Accoutrement Paraphernalia


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Accrue Accumulate

Acerbity Harshness

Acrid Sharp

Actuarial Calculating

Adage Saying

Addendum Addition

Addled Not fresh

Adept Expert at

Adjure Exhort

Admonish Rebuke

Adroit Adept

Advert Refer to

Aerie Eyrie

Affable Pleasant

Affected Mannered

Agility Nimbleness

Agog Curious

Alacrity Promptness

Alcove Recess

Alfresco Outdoor

Allay Calm

Allegiance Loyality

Allure Attract

Aloof Reserved

Amble Stroll

Ambulatory Walking

Ameliorate Improve

Amiable Polite


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Amorous Loving

Amulet Charm

Anguish Pain

Annals Records

Anomaly Oddity

Antediluvian Ancient

Aphorism Maxim

Apostate Defector

Apothegm Adage

Apparition Ghost

Appellation Epithet

Apprehend Grasp

Argot Slang

Articulate Speak

Artless Ingenious

Askew Awry

Asperity Sharpness

Assay Analyze

Assent Agree

Assiduous Diligent

Astute Wise

Atone Expiate

Aureole Halo

Austere Strict

Avarice Cupidity

Aversion Revulsion

Awry Not straight

Bacchanalian Drunken


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Bait Harass

Bane Curse

Bard Poet

Bauble Trinket

Bawdy Obscene

Beatific Blissful

Bedlam Chaos

Beholden Obligated

Bellicose Warlike

Benevolent Generous

Beseech Entreat

Besmirch Defile

Blandishment Flattery

Blasphemy Profanity

Bolster Support

Boorish Rude

Botch Mess

Bromide Platitude

Bugaboo Bugbear

Byzantine Complicated

Dally Procrastinate

Dank Damp

Debacle Fiasco

Decoy Lure

Deleterious Harmful

Delude Deceive

Demented Insane

Demotic Colloquial


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Demur Hesitate

Deride Ridicule

Desecrate Defile

Despot Dictator

Destitute Poor

Detrimental Harmful

Diabolical Devilish

Diadem Crown

Diatribe Invective

Dictum Saying

Dingy Dull

Disaffected Disloyal

Disband Separate

Discern Know

Disgorge Vomit

Dissuade Discourage

Distill Refine

Divulge Reveal

Dregs Sediment

Drivel Nonsense

Droll Funny

Dross Garbage

Facetious Humorous

Faction Opposition

Falter Hesitate

Fatuous Foolish

Fetter Shackle

Febrile Nervous


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Fecundity Fertility

Feign Pretend

Fiat Command

Filch Steal

Filial Duties

Finicky Fussy

Fissure Crevice

Flaccid Weak

Flag Droop

Flay Criticize

Flounder Hesitate

Flux Flowing

Foment Incite

Forbearance Patience

Fortitude Bravery

Foster Encourage

Fracas Melee

Frail Weak

Fraught Filled

Fugitive Evanescent

Furtive Surreptitious

Gag Joke

Gamely Resolutely

Gamut Range

Gaunt Angular

Garish Gaudy

Garner Granary

Garrulous Talkative


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Genial Amiable

Germane Apposite

Giddy Dizzy

Glower Glare

Glut Surplus

Gnarled Knotted

Goad Stimulate

Gratis Free

Gravity Enormity

Grisly Ghastly

Grouch Complaint

Gruff Impatient

Grumpy Gruff

Guffaw Chortle

Gully Ravine

Gusto Zest

Haughty Arrogant

Hegemony Dominance

Hermetic Closed

Hiatus Gap

Horrendous Terrible

Hubris Pride

Humdrum Monotonous

Humility Humbleness

Hummock Knoll

Jaunt Trip

Jejune Dull

Jeopardize Imperil


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Jibe Gibe

Jocose Humorous

Jocund Enjoying

Kindle Motivate

Knave Dishonest

Labile Unstable

Languid Weary

Larceny Theft

Lax Careless

Lechery Lustfulness

Leery Wary

Levity Frivolity

APPENDIX B: Electronic Dictionary Code

#include

#include

#include

#include

#include


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#define BIT0 0x01

#define BIT1 0x02

#define BIT2 0x04

#define BIT3 0x08

#define BIT4 0x10

#define BIT5 0x20

#define BIT6 0x40

#define BIT7 0x80

#define CHECKBIT(x,b) (x&b)

#define SETBIT(x,b) x = x|b;

#define CLEARBIT(x,b) x = x&(~b);

#define TOGGLEBIT(x,b) x = x^b;

#define TOTAL 50

unsigned char flag_error=1;

//const char *words[TOTAL]={"AB","ABACUS","BOY","MS","dog","fiscal"};

//const char *meaning[TOTAL]={"ab1","abacus2","boy3","ManishSharma","dog5","fiscal6"};

const char*words[TOTAL]={"ABERRANT","ABET","ABHOR","ABJURE","ABNEGATE","ABORGATE","ABSCISSION","ABSCOND","ABSOLVE","ABYSMAL","ACCEDE","ACCESSORY","ACCURE","ACRID","ADAGE","ADDENDUM","ADJURE","ADJUTAN

T","ADMONISH","ADROIT","ADVERT","AFFABLE","AFFECTED","AFFRONT","ACLOVE","ALFRESCO","ALLAY","ALLEVIATE","ALLUDE","ALLURE","ALOOF","AMBLE","AMELIORATE","AMIABLE","ANGUISH","ANNALS","ANOMLY","ANTEDILUVIAN","APOTHEGM","APPARITION","APPELATION","APPREHEND","ARTLESS","ASSAY","ASSIDUOUS","AUGMENT","BAFFLE","BALEFUL","BARD","BEDRAGGLED"};

const char *meaning[TOTAL]={"abnormal","to make sb to do wrong","tohate","renounce","to give up","abolish","separation","to escape","to pardon","dismal","toagree a proposal","accomplice","accumulate","sharp","wisesaying","addition","exhort","assistant","rebuke","adept","refer

to","pleasant","mannered","to insult","recess","outdoor","calm","relive","referindirectly","to attract","reserved","stroll","improve","polite","accute pain","historicalrecords","oddity","extremely ancient","adage","ghost","thing or place","to


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understand","honest","analyze","dilligent","suplement","confuse","sinister","poet","madewet"};

int mycmp(const char *ch1,const char *ch2)

{

unsigned char i=0;

while((*(ch1+i)==*(ch2+i))&& *(ch1+i)!='\0')

{

i++;

}

return (*(ch1+i)- *(ch2+i));

}

int binary_search(const char *cmp)

{

int min=0,max=TOTAL-1;

int flag=1,pointer;

while(flag)

{

pointer=(min+max)/2;

flag=mycmp(words[pointer],cmp);

if(flag==0) break;

else if(flag


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if(max


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else if(CHECKBIT(PIND,BIT5) && !CHECKBIT(PINA,BIT0))

{

return 5;

}

else if(CHECKBIT(PIND,BIT5) && CHECKBIT(PINA,BIT0))

{

return 6;

}


{

return 7;

}


{

return 8;

}

//else continue;

}

CLEARBIT(PORTD,BIT0);

SETBIT(PORTD,BIT1);

//WaitMs(100);

{

if(CHECKBIT(PIND,BIT7) && !CHECKBIT(PINA,BIT0))

{

return 9;

}


{return 10;


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}


{

return 11;

}


{

return 12;

}


{

return 13;

}


{

return 14;

}


{

return 15;

}


{

return 16;

}

}


SETBIT(PORTD,BIT2);//WaitMs(100);


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{


{

return 17;

}


{

return 18;

}


{

return 19;

}


{

return 20;

}


{

return 21;

}


{

return 22;

}


{

return 23;}


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{

return 24;

}

}


SETBIT(PORTD,BIT3);

//WaitMs(100);

{


{

return 25;

}


{

return 26;

}

else if(CHECKBIT(PIND,BIT6))

{

return 27;//backspace

}


{

return 28;//enter

}


{return 29;//reset program


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}


SETBIT(PORTD,BIT0);

}

}

}

int avr_init()

{

lcd_init();

lcd_string("INITIALISING...");

WaitMs(1000);

DDRB=0x00;

if(!CHECKBIT(PINB,BIT1))

{

lcd_cmd(0x01);

lcd_string("Error memory not found");

flag_error=0;

}

else

{

DDRB=0xff;

}

WaitMs(1000);

DDRD=0x0f;

//DDRB=0xff;DDRA=0x00;


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return 0;

}

//for microcontroller 1

void uart0_init(void)

{

UCSRB = 0x00; //disable while setting baud rate

UCSRA = 0x00;

UCSRC = BIT(URSEL) | 0x06;

UBRRL = 0x33; //set baud rate loUBRRH = 0x00; //set baud rate hi

UCSRB = 0x98;

}

//**************************************************

//Function to receive a single byte

//*************************************************

unsigned char receiveByte( void )

{

unsigned char data, status;

while(!(UCSRA & (1


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//***************************************************//Function to transmit a string stored in Flash

//***************************************************

void transmitString_F(const unsigned char* string)

{

while (*string)

transmitByte(*string++);

}

//***************************************************

//Function to transmit a string from RAM

//***************************************************

void transmitString(unsigned char* string)

{

while (*string)


}

//******************** END ********************

int main()

{

avr_init();

int ch;

char str[16]="";

int point=0;

char no;

DDRB = 0xFF;

DDRD = 0x0F;

DDRA = 0x00;

//PORTA= 0x00;


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unsigned char i=0;

if(flag_error)

{

lcd_cmd(0x01);

lcd_string("E DICTIONARY");

WaitMs(1000);

lcd_cmd(0x01);

}

while(1)

{

str[0]='\0';

point=0;

lcd_cmd(0x01);

while(flag_error)

{

ch=getkey();

WaitMs(100);

if(ch==1)

{

str[point]='A';

lcd_char('A');

point++;

}

if(ch==2)

{

str[point]='B';

lcd_char('B');point++;


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}

if(ch==3)

{

str[point]='C';

lcd_char('C');

point++;

}

if(ch==4)

{

str[point]='D';

lcd_char('D');

point++;

}

if(ch==5)

{

str[point]='E';

lcd_char('E');

point++;

}

if(ch==6)

{

str[point]='F';

lcd_char('F');

point++;

}

if(ch==7)

{

str[point]='G';lcd_char('G');


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point++;

}

if(ch==8)

{

str[point]='H';

lcd_char('H');

point++;

}

if(ch==9)

{

str[point]='I';

lcd_char('I');

point++;

}

if(ch==10)

{

str[point]='J';

lcd_char('J');

point++;

}

if(ch==11)

{

str[point]='K';

lcd_char('K');

point++;

}

if(ch==12)

{str[point]='L';


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lcd_char('L');

point++;

}

if(ch==13)

{

str[point]='M';

lcd_char('M');

point++;

}

if(ch==14)

{

str[point]='N';

lcd_char('N');

point++;

}

if(ch==15)

{

str[point]='O';

lcd_char('O');

point++;

}

if(ch==16)

{

str[point]='P';

lcd_char('P');

point++;

}

if(ch==17){


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str[point]='Q';

lcd_char('Q');

point++;

}

if(ch==18)

{

str[point]='R';

lcd_char('R');

point++;

}

if(ch==19)

{

str[point]='S';

lcd_char('S');

point++;

}

if(ch==20)

{

str[point]='T';

lcd_char('T');

point++;

}

if(ch==21)

{

str[point]='U';

lcd_char('U');

point++;

}if(ch==22)


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{

str[point]='V';

lcd_char('V');

point++;

}

if(ch==23)

{

str[point]='W';

lcd_char('W');

point++;

}

if(ch==24)

{

str[point]='X';

lcd_char('X');

point++;

}

if(ch==25)

{

str[point]='Y';

lcd_char('Y');

point++;

}

if(ch==26)

{

str[point]='Z';

lcd_char('Z');

point++;}


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else if(ch==27)

{

//command to backspace on lcd;

//printf("\b%c\b",' ');

point--;

lcd_gotoxy1(point);

lcd_char(' ');

lcd_gotoxy1(point);

}

else if(ch==28)

{

lcd_cmd(0x01);

str[point]='\0';

lcd_string("Searching...");

no=binary_search(str);

//lcd_showvalue(no);

WaitMs(200);

//if(noTOTAL)

{

lcd_cmd(0x01);

lcd_string("NOT FOUND");

WaitMs(1000);

break;

//command to print word not found

//printf("\n%s not found",str);

}else


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{

//command to print on lcd the meaning

//printf("\n %s",meaning[no]);

lcd_cmd(0x01);

PORTB=0xff;

SETBIT(PORTB,BIT0);

lcd_string(meaning[no]);

WaitMs(2000);

CLEARBIT(PORTB,BIT0);

PORTB=0x00;

break;

// printf("\n");

}

break;

}

else if(ch==29)

{

break;

}

else

{

continue;

}

}

}

while(1);return 0;


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}

//for microcontroller 2

void uart0_init(void)

{

UCSRB = 0x00; //disable while setting baud rate

UCSRA = 0x00;

UCSRC = BIT(URSEL) | 0x06;

UBRRL = 0x33; //set baud rate lo

UBRRH = 0x00; //set baud rate hi

UCSRB = 0x98;

}

//**************************************************

//Function to receive a single byte

//*************************************************

unsigned char receiveByte( void )

{

unsigned char data, status;

while(!(UCSRA & (1


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//***************************************************

//Function to transmit a string stored in Flash//***************************************************

void transmitString_F(const unsigned char* string)

{

while (*string)


}

//***************************************************

//Function to transmit a string from RAM

//***************************************************

void transmitString(unsigned char* string)

{

while (*string)


}

//******************** END ********************

void main()

{

DDRD=0xff;

PORTD=0xff;

DDRC=0xff;

PORTC=0xff;

WaitMs(100);

PORTC=0x00;

DDRD=0x00;

while(1)

{

if(CHECKBIT(PIND,BIT6))

{

PORTC=0xff;

}


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else

{PORTC=0x00;} }}

Appendix C: Softwares Used

1. WIN AVR Complier for AVR Microcontroller C programs.

2. AVR Studio Integrated Development Environment for AVR.

3. Pony Prog For programming the Atmega32L using USB port.


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REFERENCES

Books:

1. Embedded C Programming and the Atmel AVR, 2nd Edition Barnett. Cox and

OCull

2. Programming and Customizing the AVR Microcontroller Dhananjay V. Gadre

Internet:

1. http://www.dharmanitech.com/

For keypad design and interface

1. http://www.scienceprog.com/connect-lcd-to-atmega-using-3-wires/ece-wise

For LCD programming

1. http://extremeelectronics.co.in/avr-tutorials/using-the-usart-of-avr-

microcontrollers-reading-and-writing-data/

For interface of two atmega32
http://www.dharmanitech.com/http://extremeelectronics.co.in/avr-tutorials/using-the-usart-of-avr-microcontrollers-reading-and-writing-data/http://extremeelectronics.co.in/avr-tutorials/using-the-usart-of-avr-microcontrollers-reading-and-writing-data/http://www.dharmanitech.com/http://extremeelectronics.co.in/avr-tutorials/using-the-usart-of-avr-microcontrollers-reading-and-writing-data/http://extremeelectronics.co.in/avr-tutorials/using-the-usart-of-avr-microcontrollers-reading-and-writing-data/

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