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CHAPTER 1

INTRODUCTION

Embedded systems are computers which are part of special-purpose devices.

Due to the limited duties this systems can be highly optimized to the particular

needs. Traditionally most of this systems are used for control and process

measurement, as a side-effect of higher integration of integrated circuits more

complex applications can be solved by embedded systems. To be able to solve

these problems embedded systems are commonly equipped with various kinds of

peripherals. Early applications of embedded devices include the guidancecomputer of the Minuteman I missiles and the Apollo guidance computer. The

Minuteman I & II missiles are intercontinental ballistic nuclear warheads,

produced by Boeing in the 1960s. Due to the large quantities of ICs used in the

guidance system of Minuteman II missiles, prices for ICs fell from 1000$ each to

3$ each. This lead to wide adoption of embedded systems in consumer electronics

in the 1980s. Nowadays embedded systems can be found in devices from digital

watches to traffic-control systems. The broad ranges of applications with totally

different requirements lead to various implementation approaches

1.1HARDWARE PLATFORMS

Based on the metrics, introduced in the above section, processors for

embedded systems can be distinguished by the grade of customization they grant

and the performance they achieve.

Examples are:

Motorola ARM

Atmel AVR

Microchip PIC

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Intel Pentium-(I/II/III/IV)-Series

AMD Athlon (or other)

VIA EDEN

1.2PROGRAMMING EMBEDDED SYSTEMS

Unlike personal computers, embedded systems usually arent programmed

on the platform the program is intended to run. This requires special tool chains

with cross-compilers and emulators to test the code before deploying it to the target

platform. Depending on the applications needs, there are different approaches to

implement the software. One possibility is to directly control the hardware out of

the program. This is the approach with the highest performance, but requires more

knowledge about the used architecture and peripherals than using an operating

system. On the other hand operating systems provide functionalities for

multiprocessing and allow the designer to develop mostly independent from the

underlying architecture.

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1.3 BLOCK DIAGRAM

1.3.1RECEIVER:

3

MICROCONTROLLER89C51

PC

POWERSUPPLY

HT 648

DECODER

RF Rxer

GSM


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1.3.2TRANSMITTER:

4

RFIDREADER

MICROCONTROLER89C51

RFID TAG

RFID TAG

RFID TAG

IRSENSOR

POWERSUPPLY

LCD

HT 640

ENCODER

RF Txer


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CHAPTER 2

MICROCONTROLLER

2.1INTRODUCTION:

A microcontroller is a complete microprocessor system built on a single IC.

Microcontrollers were developed to meet a need for microprocessors to be put into

low cost products. Building a complete microprocessor system on a single chip

substantially reduces the cost of building simple products, which use the

microprocessor's power to implement their function, because the microprocessor is

a natural way to implement many products. This means the idea of using a

microprocessor for low cost products comes up often. But the typical 8-bit

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microprocessor based system, such as one using a Z80 and 8085 is expensive. Both

8085 and Z80 system need some additional circuits to make a microprocessor

system. Each part carries costs of money. Even though a product design may

require only very simple system, the parts needed to make this system as a low cost

product.

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2.2APPLICATIONS OF MICROCONTROLLERS

Microcontrollers are designed for use in sophisticated real time applications

such as

1. Industrial Control

2. Instrumentation and

3. Intelligent computer peripherals

They are used in industrial applications to control

Motor

Robotics

Discrete and continuous process control

In missile guidance and control

In medical instrumentation

Oscilloscopes

Telecommunication

Automobiles

For Scanning a keyboard

Driving an LCD

For Frequency measurement

CHAPTER 3

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RADIO FREQUENCY

3.1 INTRODUCTION

The mode of communication for wireless technologies of all kinds,

including cordless phones, radar, ham radio, GPS, and radio and television

broadcasts. RF technology is so much a part of our lives we scarcely notice it for

its ubiquity. From baby monitors to cell phones, Bluetooth to remote control

toys, RF waves are all around us. RF waves are electromagnetic waves which

propagate at the speed of light, or 186,000 miles per second (300,000 km/s). The

frequencies of RF waves, however, are slower than those of visible light, making

RF waves invisible to the human eye.

The frequency of a wave is determined by its oscillations or cycles per

second. One cycle is one hertz (Hz); 1,000 cycles is 1 kilohertz (KHz); 1 million

cycles is 1 megahertz (MHz); and 1 billion cycles is 1 gigahertz (GHz). A station

on the AM dial at 980, for example, broadcasts using a signal that oscillates

980,000 times per second, or has a frequency of 980 KHz. A station a little further

down the dial at 710 broadcasts using a signal that oscillates 710,000 times a

second, or has a frequency of 710 KHz. With a slice of the RF pie licensed to each

broadcaster, the RF range can be neatly divided and utilized by multiple parties.

3.2RFID Reader

An RFID reader is a device that is used to interrogate an RFID tag. The

reader has an antenna that emits radio waves; the tag responds by sending back its

data.

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A number of factors can affect the distance at which a tag can be read (the

read range). The frequency used for identification, the antenna gain, the orientation

and polarization of the reader antenna and the transponder antenna, as well as the

placement of the tag on the object to be identified will all have an impact on the

RFID systems read range.

3.2.1Types:

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There are three types of RFID tags: active RFID tags, passive RFID tags,

and semi-passive RFID tags. Active RFID tags are typically larger and more

expensive to produce, since they require a power source. Active RFID tags

broadcast their signal to the reader, and are typically more reliable and accurate

than passive RFID tags. Since active RFID tags have a stronger signal, they are

more adept for environments that make it hard to transmit other types of tags, such

as under water, or from farther away.

Passive RFID tags, on the other hand, do not have internal power supplies

and rely on the RFID reader to transmit data. A small electrical current is received

through radio waves by the RFID antenna, and power the CMOS just enough to

transmit a response. Passive RFID tags are more suited for warehousing

environments where there is not a lot of interference, and relatively short distances

(typically ranging anywhere from a few inches to a few yards). Since there is no

internal power supply, passive RFID tags are much smaller and cheaper to

produce.

3.3RF TRANSMITTER

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3.3.1Features:

Modulate Mode: ASK

Circuit Shape: SAW

Date Rate: 8kbps

Supply Voltage: 3~ 12 V

Power Supply and All Input / Output Pins: -0.3 to +12.0 V

Non-Operating Case Temperature: -20 to +85

Soldering Temperature ( 10 Seconds ) : 230 ( 10 Seconds)

Frequency Range: 433.92 MHz

3.3.2Electrical Characteristics:

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3.3.3Application Note:

3.4RF RECEIVER

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3.4.1Features:

Frequency Range: 433.92 MHZ

Modulate Mode: ASK

Circuit Shape: LC

Date Rate: 4800 bps

Selectivity: -106 dB

Channel Spacing: 1MHZ

Supply Voltage: 5V

High Sensitivity Passive Design.

Simple To Apply with Low External Count.

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3.4.2DC Characteristics

3.4.3Electrical Characteristics

3.4.4Application Note:

CHAPTER 4

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4.1IR SENSOR

The IR sensor is a very simple device that works by reflecting infrared light

off of an object and detecting the reflecting with a photo-transistor that is tuned to

the same frequency of light. The LED is mounted next to the photo-transistor,

however, the emitted light from the LED does not directly shine into the photo-

transistor. Appropriate values for resistance are in series with both the LED to limit

current and the photo-transistor in order to show a voltage drop based on distance

to the object in front of the sensor. The effective range of the sensor is a few

centimeters. Object detection can be enhanced by placing a reflective surface

between the object and the sensor. When the object passes between the sensor and

reflective surface, a large drop will be observed in the output signal.

4.2Applications:

CCD Camera

Night Vision

Infrared Applied System

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4.3Dimensions

IR-1WS-850

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CHAPTER 5

5.1MAX 232:

The MAX232 is an integrated circuit that converts signals from an RS-232

serial port to signals suitable for use in TTL compatible digital logic circuits. The

MAX232 is a dual driver/receiver and typically converts the RX, TX, CTS andRTS signals.

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

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

it useful for implementing RS-232 in devices that otherwise do not need any

voltages outside the 0 V to + 5 V range, as power supply design does not need to

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

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

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

typical hysteresis of 0.5 V.

The later MAX232A is backwards compatible with the original MAX232

but may operate at higher baud rates and can use smaller external capacitors 0.1

F in place of the 1.0 F capacitors used with the original device.

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The newer MAX3232 is also backwards compatible, but operates at a

broader voltage range, from 3 to 5.5V.

5.2VOLTAGE LEVELS

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

MAX232 IC receives a TTL level to convert, it changes a TTL Logic 0 to between

+3 and +15V, and changes TTL Logic 1 to between -3 to -15V, and vice versa for

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

RS232 Data Transmission voltages at a certain logic state are opposite from the

RS232 Control Line voltages at the same logic state.

CHAPTER 6

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6.1 GSM:

The Global System for Mobile communication (GSM) is a huge, rapidly

expanding and successful technology. Less than five years ago, there were a small

number of companies working on GSM. Each of these companies had a few GSM

experts who brought knowledge back from the European Telecommunications

Standards Institute committees designing the GSM specification. Currently, there

are hundreds of companies working on GSM and thousands of GSM experts.

In the US, bands have been allocated at approximately 2 GHz for a personal

communications system (PCS). Unlike Europe and the Far East, the PCS license

holders will not be forced to use any particular radio technology. The three main

system contenders are GSM, code-division multiple access and 15-136 time-

division multiple access (TDMA), all likely to have nationwide coverage. The

ready availability of GSM equipment and expertise has made GSM at 1.9 GHz

attractive for many operators. PCS1900 operators have banded together to form the

North American Interest Group and help advance the development of GSM. Theseven member companies include American Personal Communications (APC),

American Portable Telecom, Bell South Personal Communications, Intercel,

Omnipoint, Pacific Bell Mobile Services and Western Wireless Co. Many of the

large GSM manufacturers are also backing PCS1900, including Nokia, Ericsson,

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Matra, AEG and Northern Telecom. The first commercial PCS system based on

PCS1900 was launched by APC under the Sprint Spectrum name on November 15,

1995. The majority of US PCS licenses will became operational over the next two

years.

A GSM network is composed of several functional entities, whose functions

and interfaces are defined.

The GSM network can be divided into three broad parts. The Mobile Station

is carried by the subscriber, the Base Station Subsystem controls the radio link

with the Mobile Station. The Network Subsystem, the main part of which is the

Mobile services Switching Center, performs the switching of calls between the

mobile and other fixed or mobile network users, as well as management of mobile

services, such as authentication. Not shown is the Operations and Maintenance

center, which oversees the proper operation and setup of the network. The Mobile

Station and the Base Station Subsystem communicate across the Um interface, also

known as the air interface or radio link. The Base Station Subsystem

communicates with the Mobile service Switching Center across the A interface.

6.2Mobile Station:

The mobile station (MS) consists of the physical equipment, such as the

radio transceiver, display and digital signal processors, and a smart card called the

Subscriber Identity Module (SIM). The SIM provides personal mobility, so that

the user can have access to all subscribed services irrespective of both the location

of the terminal and the use of a specific terminal. By inserting the SIM card into

another GSM cellular phone, the user is able to receive calls at that phone, make

calls from that phone, or receive other subscribed services.

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The mobile equipment is uniquely identified by the International Mobile

Equipment Identity (IMEI). The SIM card contains the International Mobile

Subscriber Identity (IMSI), identifying the subscriber, a secret key for

authentication, and other user information. The IMEI and the IMSI are

independent, thereby providing personal mobility. The SIM card may be protected

against unauthorized use by a password or personal identity number.

6.3Base Station Subsystem:

The Base Station Subsystem is composed of two parts, the Base Transceiver

Station (BTS) and the Base Station Controller (BSC). These communicate across

the specified Abis interface, allowing (as in the rest of the system) operation

between components made by different suppliers.

The Base Transceiver Station houses the radio tranceivers that define a cell

and handles the radiolink protocols with the Mobile Station. In a large urban

area, there will potentially be a large number of BTSs deployed. The requirements

for a BTS are ruggedness, reliability, portability, and minimum cost.

The Base Station Controller manages the radio resources for one or more

BTSs. It handles radiochannel setup, frequency hopping, and handovers, as

described below. The BSC is the connection between the mobile and the Mobile

service Switching Center (MSC). The BSC also translates the 13 kbps voice

channel used over the radio link to the standard 64 kbps channel used by the Public

Switched Telephone Network or ISDN.

Network Subsystem

The central component of the Network Subsystem is the Mobile services

Switching Center (MSC). It acts like a normal switching node of the PSTN or

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ISDN, and in addition provides all the functionality needed to handle a mobile

subscriber, such as registration, authentication, location updating, handovers, and

call routing to a roaming subscriber. These services are provided in conjuction

with several functional entities, which together form the Network Subsystem. The

MSC provides the connection to the public fixed network (PSTN or ISDN), and

signalling between functional entities uses the ITUT Signalling System

Number 7 (SS7), used in ISDN and widely used in current public networks.

The Home Location Register (HLR) and Visitor Location Register (VLR),

together with the MSC, provide the callrouting and (possibly international)

roaming capabilities of GSM. The HLR contains all the administrative

information of each subscriber registered in the corresponding GSM network,

along with the current location of the mobile. The current location of the mobile is

in the form of a Mobile Station Roaming Number (MSRN) which is a regular

ISDN number used to route a call to the MSC where the mobile is currently

located. There is logically one HLR per GSM network, although it may be

implemented as a distributed database.

The Visitor Location Register contains selected administrative information

from the HLR, necessary for call control and provision of the subscribed services,

for each mobile currently located in the geographical area controlled by the VLR.

Although each functional entity can be implemented as an independent unit, most

manufacturers of switching equipment implement one VLR together with one

MSC, so that the geographical area controlled by the MSC corresponds to that

controlled by the VLR, simplifying the signalling required. Note that the MSC

contains no information about particular mobile stations - this information is stored

in the location registers.

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The other two registers are used for authentication and security purposes.

The Equipment Identity Register (EIR) is a database that contains a list of all valid

mobile equipment on the network, where each mobile station is identified by its

International Mobile Equipment Identity (IMEI). An IMEI is marked as invalid if

it has been reported stolen or is not type approved. The Authentication Center is a

protected database that stores a copy of the secret key stored in each subscriber's

SIM card, which is used for authentication and ciphering of the radio channel.

6.4SIM:

A SIM card or Subscriber Identity Module is a portable memory chip used in

some models of cellular telephones. The SIM card makes it easy to switch to a new

phone by simply sliding the SIM out of the old phone and into the new one. The

SIM holds personal identity information, cell phone number, phone book, text

messages and other data. It can be thought of as a mini hard disk that automatically

activates the phone into which it is inserted.

A SIM card can come in very handy. For example, let's say your phone runs

out of battery power at a friend's house. Assuming you both have SIM-based

phones, you can remove the SIM card from your phone and slide it into your

friend's phone to make your call. Your carrier processes the call as if it were made

from your phone, so it won't count against your friend's minutes.

If you upgrade your phone there's no hassle involved. The SIM card is all

you need. Just slide it into the new phone and you're good to go. You can even

keep multiple phones for different purposes. An inexpensive phone in the glove

compartment, for example, for emergency use, one phone for work and another for

home. Just slide your SIM card into whatever phone you wish to use.

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High-end cell phones can be very attractive and somewhat pricey. If you

invest in an expensive phone you might want to keep it awhile. Using a SIM card,

it is even possible to switch carriers and continue to use the same phone. The new

carrier will simply issue you their own SIM card. The phone must be unlocked,

however, and operate on the new carrier's frequency or band.

A SIM card provides an even bigger advantage for international travelers --

simply take your phone with you and buy a local SIM card with minutes. For

example, a traveler from the U.S. staying in the U.K. can purchase a SIM card

across the pond. Now the phone can be used to call throughout England without

paying international roaming charges from the carrier back home.

6.5GSM MODEM:

A GSM modem is a specialized type of modem which accepts a SIM card,

and operates over a subscription to a mobile operator, just like a mobile phone.

From the mobile operator perspective, a GSM modem looks just like a mobile

phone.

A GSM modem can be a dedicated modem device with a serial, USB or

Bluetooth connection, or it may be a mobile phone that provides GSM modem

capabilities.

For the purpose of this document, the term GSM modem is used as a generic

term to refer to any modem that supports one or more of the protocols in the GSM

evolutionary family, including the 2.5G technologies GPRS and EDGE, as well as

the 3G technologies WCDMA, UMTS, HSDPA and HSUPA.

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A GSM modem exposes an interface that allows applications such as

NowSMS to send and receive messages over the modem interface. The mobile

operator charges for this message sending and receiving as if it was performed

directly on a mobile phone. To perform these tasks, a GSM modem must support

an "extended AT command set" for sending/receiving SMS messages, as defined in

the ETSI GSM 07.05 and and 3GPP TS 27.005 specifications.

GSM modems can be a quick and efficient way to get started with SMS,

because a special subscription to an SMS service provider is not required. The

mobile operator charges for this message sending and receiving as if it was

performed directly on a mobile phone. In most parts of the world, GSM modems

are a cost effective solution for receiving SMS messages, because the sender is

paying for the message delivery.

Historically, we have recommended GSM modems from manufacturers such

as Multitech, Falcom, Siemens (now Cinterion), iTegno and Wavecom. While

these manufacturers make very good GSM modems, there are currently a lot of

GSM/3G USB stick modems available on the market, which are less expensive

(under $100), and in many cases significantly faster than older GSM modems.

Some recommended GSM/3G USB modems include the Option ICON 322,

Sierra Wireless Compass 885, SonyEricsson MD300, Novatel MC950D and

Huawei E160. Many other models from these manufacturers will also work well

with NowSMS.

We have posted some notes about experiences with specific modem models

at the following link: http://blog.nowsms.com/search/label/GSM%20modem.

A GSM modem could also be a standard GSM mobile phone with the

appropriate cable and software driver to connect to a serial port or USB port on

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your computer. Any phone that supports the "extended AT command set" for

sending/receiving SMS messages, as defined in ETSI GSM 07.05 and/or 3GPP TS

27.005, can be supported by the Now SMS/MMS Gateway. Note that not all

mobile phones support this modem interface.

Due to some compatibility issues that can exist with mobile phones, using a

dedicated GSM modem is usually preferable to a GSM mobile phone. This is more

of an issue with MMS messaging, where if you wish to be able to receive inbound

MMS messages with the gateway, the modem interface on most GSM phones will

only allow you to send MMS messages. This is because the mobile phone

automatically processes received MMS message notifications without forwarding

them via the modem interface.

It should also be noted that not all phones support the modem interface for

sending and receiving SMS messages. In particular, most smart phones, including

Blackberries, iPhone, and Windows Mobile devices, do not support this modem

interface at all.Nokia phones that use the S60 (Series 60) interface, which is

Symbian based, only support sending SMS messages via the modem interface, and

do not support receiving SMS via the modem interface. Nokia phones using the

Series 40 3rd Generation or later interface have similar limitations and do not

support receiving SMS via the modem interface. This makes most Nokia phones

incompatible with the 2-way SMS functionality of NowSMS.

SonyEricsson phones generally have a good full GSM modem

implementation (except for the P and X series which use UIQ/Symbian or

Windows Mobile). They can be used for sending/receiving SMS messages and

sending MMS messages.

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Motorola phones have a bug in their GSM modem implementation that

prevents them from being able to send binary SMS messages. They can

send/receive SMS text messages, and send MMS messages.

While using a phone as a modem may be a good way to get started with

NowSMS, the best solution is to use a dedicated GSM modem device, such as the

GSM/3G USB modems mentioned earlier on this page.

Additional notes about experiences with specific modem models can be found at

the following link: http://blog.nowsms.com/search/label/GSM%20modem

The Now SMS/MMS gateway can simultaneously support multiple modems,

provided that your computer hardware has the available communications port

resources.

6.6GSM MODULE WITH RS232:

GSM module GPRS module characteristics:

Full Type Approved Quad Band Embedded GSM Module (GSM

850/900 1800/1900) with AT command set and RS232 interface on

CMOS level.

This GSM wireless data module is the ready a solution for remote

wireless applications, machine to machine or user to machine and

remote data communications in all vertical market applications.

The GSM module offers the advantages as below

Ultra small size (22x22x3 mm), lightweight (3.2 g) and easy to

integrate

R&TTE type approval plus CE, GCF, FCC, PTCRB, IC

Full RS232 on CMOS level with flow control (RX, TX, CTS,

RTS, CTS, DTR, DSR, DCD, RI)

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Embedded TCP/IP Stack UDP/IP Stack , Embedded FTP and

SMTP Client

High performance on low price

Smallest size designed for tiny applications

Tracking (people, animals, people), container tracking, PDA, POS

terminal, PCMCIA cards, AMR

Pin to Pin upgrade policy to save your developing investments

High level technical support to help you in the integration of your

solution

Exhaustive product documentation

Evaluation kit and reference design

6.7Product Features:

E-GSM 900/1800 MHz and GSM 1800/1900 with GSM Phase 2 / 2+

Output Power Class 4 (2W) at GSM 850/900 MHz and Class 1 (1W) at

GSM 1800/1900 MHz

Control via AT commands (ITU, GSM, GPRS and manufacturer

supplementary)

Supply Voltage range: 3.22 V - 4.2 V, nominal: 3.8 V

Power consumption: Idle mode:


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Analogue audio for microphone, speaker and hands free set plus digital

voice interface

RS232 on CMOS 2,8 V (One RS232 (2,8V) with flow control (RX, TX,

CTS, RTS, CTS, DTR, DSR, DCD, RI), baud rate 300 - 115.200 bps,

autobauding 1200 - 57.600 bps

50 Ohm antenna connector

6.7.2Audio:

Telephony and emergency calls (Half Rate (HR), Full Rate (FR), Enhanced

Full Rate (EFR))

Echo cancellation and noise reduction

6.7.3SMS:

SMS Mobile Originated (MO), Mobile Terminated (MT) and Cell Broadcast

(CB - DRX)

6.7.4GPRS, data and Fax:

Circuit Switched Data (CSD) up to 14.4 kbps

Fax Group 3

Packed Data (GPRS class B, class 10) up to 115 kbps

6.7.5GSM Supplementary Services:

Call Barring and Call Forwarding

Advice of Charge

Call Waiting and Call Hold

Calling Line Identification Presentation (CLIP)

Calling Line Identification Restriction (CLIR)

Unstructured SS Mobile Originated Data (USSD)

Closed User Group

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CHAPTER 7

ENCODING AND DECODING

In computers, encoding is the process of putting a sequence of characters

(letters, numbers, punctuation, and certain symbols) into a specialized format for

efficient transmission or storage. Decoding is the opposite process -- the

conversion of an encoded format back into the original sequence of characters.

Encoding and decoding are used in data communications, networking, and storage.

The term is especially applicable to radio (wireless) communications systems.

The code used by most computers for text files is known as ASCII

(American Standard Code for Information Interchange, pronounced ASK-ee).

ASCII can depict uppercase and lowercase alphabetic characters, numerals,

punctuation marks, andcommon symbols. Other commonly-used codes include

Unicode, BinHex, Uuencode, and MIME. In data communications, Manchester

encoding is a special form of encoding in which the binary digits (bits) represent

the transitions between high and low logic states. In radio communications,

numerous encoding and decoding methods exist, some of which are used only by

specialized groups of people (amateur radio operators, for example). The oldest

code of all, originally employed in the landline telegraph during the 19th century,

is the Morse code.

The terms encoding and decoding are often used in reference to the

processes ofanalog-to-digital conversion and digital-to-analog conversion. In this

sense, these terms can apply to any form of data, including text, images, audio,

video, multimedia, computer programs, or signals in sensors, telemetry, and

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control systems. Encoding should not be confused with encryption, a process in

which data is deliberately altered so as to conceal its content.

PROGRAM 1:

#include

#include

sfr lcd=0xa0;

sbit rs=P3^2;

sbit rw=P3^3;

sbit en=P3^4;

sbit En1=P0^4;

sbit En2=P0^5;

sbit En3=P0^6;

sbit En4=P0^7;

sbit TE=P3^5;

sbit sw=P3^6;

sbit buzz=P3^7;

unsigned char *volt=" Student RFID ";

unsigned char *volt1=" Student A ";

unsigned char *volt2=" Student B ";

unsigned char *volt3=" Student C ";

unsigned char *volt4=" Student D ";

unsigned char *volt5=" Show Your Card ";

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unsigned char card[11];

unsigned char a[9]="05356881";

unsigned char b[9]="05354915";

unsigned char c[9]="21460410";

unsigned char d[9]="05345786";

unsigned char m,n,o,p,q;

void delay(unsigned int w);

void lcd_cmd(unsigned char val);

void lcd_data1(unsigned char *val2);

void lcd_cmd(unsigned char val)

{

rs=0;

rw=0;

lcd=val;

en=1;

delay(10);

en=0;

}

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void lcd_data1(unsigned char *val2)

{

for(;*val2;)

{

rs=1;

rw=0;

lcd=*val2++;

en=1;

delay(10);

en=0;

}

}

void delay(unsigned int w)

{

unsigned int i,j;

for(i=0;i


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{

TE=1;

buzz=1;

lcd_cmd(0x38);

delay(1);

lcd_cmd(0x01);

delay(1);

lcd_cmd(0x0e);

delay(1);

lcd_cmd(0x06);

delay(1);

lcd_cmd(0x80);

lcd_data1(volt);

lcd_cmd(0xC0);

SCON=0x50;

TMOD=0x20;

TH1=0xFD;

TR1=1;

IE=0x85;

En1=1;

En2=1;

En3=1;

En4=1;

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while(1)

{

while(sw!=1);

buzz=0;

lcd_cmd(0xC0);

lcd_data1(volt5);

delay(10);

for(m=0;m


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delay(1);

buzz=1;

TE=0;

En1=0;

En2=0;

En3=0;

En4=1;

delay(500);

TE=1;

}

if(strncmp(b,card,8)==0)

{

lcd_cmd(0xC0);

lcd_data1(volt2);

delay(1);

buzz=1;

TE=0;

En1=0;

En2=0;

En3=1;

En4=0;

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delay(500);

TE=1;

}

if(strncmp(c,card,8)==0)

{

lcd_cmd(0xC0);

lcd_data1(volt3);

delay(1);

buzz=1;

TE=0;

En1=0;

En2=1;

En3=0;

En4=0;

delay(500);

TE=1;

}

if(strncmp(d,card,8)==0)

{

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lcd_cmd(0xC0);

lcd_data1(volt4);

delay(1);

buzz=1;

TE=0;

En1=1;

En2=0;

En3=0;

En4=0;

delay(500);

TE=1;

}

delay(50);

}

}

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PROGRAM 2:

#include

#include

sfr lcd=0xa0;

sbit rs=P3^2;

sbit rw=P3^3;

sbit en=P3^4;

sbit Dc4=P0^4;

sbit Dc3=P0^5;

sbit Dc2=P0^6;

sbit Dc1=P0^7;

sbit VT=P3^5;

unsigned char *volt=" Student RFID ";

unsigned char *volt1=" Student A ";

unsigned char *volt2=" Student B ";

unsigned char *volt3=" Student C ";

unsigned char *volt4=" Student D ";

unsigned char *volt5=" Show Your Card ";

unsigned char card[11];

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unsigned char a[9]="15314268";

unsigned char b[9]="15304459";

unsigned char c[9]="15310279";

unsigned char d[9]="15307733";

unsigned char m,n,o,p,q,str,TAG,java,z;

void delay(unsigned int w);

void lcd_cmd(unsigned char val);

void lcd_data1(unsigned char *val2);

void lcd_cmd(unsigned char val)

{

rs=0;

rw=0;

lcd=val;

en=1;

delay(10);

en=0;

}

void lcd_data1(unsigned char *val2)

{

for(;*val2;)

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{

rs=1;

rw=0;

lcd=*val2++;

en=1;

delay(10);

en=0;

}

}

void delay(unsigned int w)

{

unsigned int i,j;

for(i=0;i


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TI=0;

}

void main()

{

lcd_cmd(0x38);

delay(1);

lcd_cmd(0x01);

delay(1);

lcd_cmd(0x0e);

delay(1);

lcd_cmd(0x06);

delay(1);

lcd_cmd(0x80);

lcd_data1(volt);

lcd_cmd(0xC0);

SCON=0x50;

TMOD=0x20;

TH1=0xFD;

TR1=1;

while(1)

{

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if(Dc1==0 && Dc2==0&& Dc3==0 && Dc4== 1 && VT==1)

{

lcd_cmd(0xC0);

lcd_data1(volt1);

for(z=0;a[z]!='\0';z++)

{

transmit_data(a[z]);

delay(1);

}

delay(1000);

}

if(Dc1==0 && Dc2==0 && Dc3==1 && Dc4== 0 &&

VT==1)

{

lcd_cmd(0xC0);

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lcd_data1(volt2);

for(z=0;b[z]!='\0';z++)

{

transmit_data(b[z]);

delay(1);

}

delay(1000);

}

if(Dc1==0 && Dc2==1&& Dc3==0 && Dc4== 0 && VT==1)

{

lcd_cmd(0xC0);

lcd_data1(volt3);

for(z=0;c[z]!='\0';z++)

{

transmit_data(c[z]);

delay(1);

}

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delay(1000);

}

if(Dc1==1 && Dc2==0 && Dc3==0 && Dc4== 0 &&

VT==1)

{

lcd_cmd(0xC0);

lcd_data1(volt4);

for(z=0;d[z]!='\0';z++)

{

transmit_data(d[z]);

delay(1);

}

delay(1000);

}

}

}

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References:

[1] Qaiser, A.; Khan, S.A., Automation of Time and Attendance using RFID

Systems, International Conference on Emerging Technologies, ICET '06, 2006,

pp.60-63.

[2]Chung-Chih Lin; Ping-Yeh Lin; Po-Kuan Lu; Guan-Yu Hsieh; Wei-Lun Lee;

Ren-Guey Lee,A Healthcare Integration System for Disease Assessment and

Safety Monitoring of Dementia Patients, IEEE Transactions on Information

Technology in Biomedicine,Vol.12, No.5, 2008, pp.579-586.

[3] Ting, J.S.L.; Kwok, S.K.; Lee, W.B.; Tsang, A.H.C.; Cheung, B.C.F.,A

Dynamic RFIDBased Mobile Monitoring System in Animal Care Management

Over a Wireless Network, International Conference on Wireless

Communications, Networking and Mobile Computing, 2007,pp.2085-2088

[4]Sangyoon Chin, M.ASCE, Suwon Yoon, Cheolho Choi, and Changyon Cho ,

RFID+4D CAD for Progress Management of Structural Steel Works in High-Rise

Buildings, Journal Comp in Civil Engineering,Vol 22,No 2,2008 ,pp. 74-89

[5] Bizedge,RFID 2006-2010 Forecast and Analysis

byhttp://www.theedgedaily.com/cms/content.jsp ?

id=com.tms.cms.article.Article_d2cc4b9-

cb73c03a-29d65b00-cd5c3a50, 2006.

[6] Balachandran, G.K.; Barnett, R.E., A 110 nA Voltage Regulator System With

Dynamic Bandwidth Boosting for RFID Systems, IEEE Journal of Solid-State

Circuits, , Vol.41, No.9, 2006, pp.2019-2028.

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[7] Savi Technologies, Savi Technologies: Active and Passive RFID and Selecting

the Right Active Frequency Q.E.D System. 2005.

[8] E. Ergen, B. Akinci, B. East & J. Kirby, Tracking Components and

Maintenance History within a Facility Utilizing Radio Frequency Identification

Technology. Journal of Computing in Civil Engineering, Vol.21, No.1, 2007,

pp.11-20.

[9] J.W. Satzinger & T.U. Orvik, The ObjectOriented Approach Concepts,

System

Development and Modeling with UML. 2nd. ed. Boston: Course Technology

Thomson Learning, 2001.

[10] D.M. Kroenke, Database Concepts, Prentice Hall, Upper Saddle River, New

Jersey, 2002.

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