B 11 Documentation

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CHAPTER1

INTRODUCTION

1.1EMBEDDED SYSTEMS

Embedded systems are electronic devices that incorporate microprocessors with in

their implementations. The main purposes of the microprocessors are to simplify the system

design and provide flexibility. Having a microprocessor in the device helps in removing the

bugs, making modifications, or adding new features are only matter of rewriting the software

that controls the device. Or in other words embedded computer systems are electronic

systems that include a microcomputer to perform a specific dedicated application. The

computer is hidden inside these products. Embedded systems are ubiquitous. Every week

millions of tiny computer chips come pouring out of factories finding their way into our

everyday products.

Embedded systems are self-contained programs that are embedded within a piece of

hardware. Whereas a regular computer has many different applications and software that can

be applied to various tasks, embedded systems are usually set to a specific task that cannot be

altered without physically manipulating the circuitry. Another way to think of an embedded

system is as a computer system that is created with optimal efficiency, thereby allowing it to

complete specific functions as quickly as possible.

Embedded systems designers usually have a significant grasp of hardware

technologies. They use specific programming languages and software to develop embedded

systems and manipulate the equipment. When searching online, companies offer embedded

systems development kits and other embedded systems tools for use by engineers and

businesses.

Embedded systems technologies are usually fairly expensive due to the necessarydevelopment time and built in efficiencies, but they are also highly valued in specific

industries. Smaller businesses may wish to hire a consultant to determine what sort of

embedded systems will add value to their organization.

1.2CHARACTERISTICS:

Two major areas of differences are cost and power consumption. Since many

embedded systems are produced in tens of thousands to millions of units range, reducing cost

is a major concern. Embedded systems often use a (relatively) slow processor and small

memory size to minimize costs.

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The slowness is not just clock speed. The whole architecture of the computer is often

intentionally simplified to lower costs. For example, embedded systems often use peripherals

controlled by synchronous serial interfaces, which are ten to hundreds of times slower than

comparable peripherals used in PCs. Programs on an embedded system often run with real-time constraints with limited hardware resources: often there is no disk drive, operating

system, keyboard or screen. A flash drive may replace rotating media, and a small keypad and

LCD screen may be used instead of a PC's keyboard and screen.

Firmware is the name for software that is embedded in hardware devices, e.g. in one

or more ROM/Flash memory IC chips. Embedded systems are routinely expected to maintain

100% reliability while running continuously for long periods, sometimes measured in years.

Firmware is usually developed and tested too much harsher requirements than is general-purpose software, which can usually be easily restarted if a problem occurs.

1.3PLATFORM:

There are many different CPU architectures used in embedded designs. This in

contrast to the desktop computer market which is limited to just a few competing

architectures mainly the Intel/AMD x86 and the Apple/Motorola/IBM Power PCs which are

used in the Apple Macintosh. One common configuration for embedded systems is the system

on a chip, an application-specific integrated circuit, for which the CPU was purchased as

intellectual property to add to the IC's design.

1.4TOOLS:

Like a typical computer programmer, embedded system designers use compilers,

assemblers and debuggers to develop an embedded system. Those software tools can come

from several sources:

Software companies that specialize in the embedded market Ported from the GNU

software development tools. Sometimes, development tools for a personal computer can be

used if the embedded processor is a close relative to a common PC processor. Embedded

system designers also use a few software tools rarely used by typical computer programmers.

Some designers keep a utility program to turn data files into code, so that they can include

any kind of data in a program. Most designers also have utility programs to add a checksum

or CRC to a program, so it can check its program data before executing it.

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1.5 OPERATING SYSTEM:

They often have no operating system, or a specialized embedded operating system

(often a real-time operating system), or the programmer is assigned to port one of these to the

new system.

1.6 DEBUGGING:

Debugging is usually performed with an in-circuit emulator, or some type of debugger

that can interrupt the micro controllers internal microcode. The microcode interrupt lets the

debugger operate in hardware in which only the CPU works. The CPU-based debugger can

be used to test and debug the electronics of the computer from the viewpoint of the CPU.

Developers should insist on debugging which shows the high-level language, with

breakpoints and single stepping, because these features are widely available. Also, developers

should write and use simple logging facilities to debug sequences of real-time events. PC or

mainframe programmers first encountering this sort of programming often become confused

about design priorities and acceptable methods. Mentoring, code-reviews and ego less

programming are recommended.

1.7 DESIGN OF EMBEDDED SYSTEMS:

The electronics usually uses either a microprocessor or a microcontroller. Some large

or old systems use general-purpose mainframes computers or minicomputers.

START-UP:

All embedded systems have start-up code. Usually it disables interrupts, sets up the

electronics, tests the computer (RAM, CPU and software), and then starts the application

code. Many embedded systems recover from short-term power failures by restarting (without

recent self-tests). Restart times under a tenth of a second are common.

Many designers have found one of more hardware plus software-controlled LEDs

useful to indicate errors during development (and in some instances, after product release, to

produce troubleshooting diagnostics). A common scheme is to have the electronics turn off

the LED(s) at reset, whereupon the software turns it on at the first opportunity, to prove that

the hardware and start-up software have performed their job so far. After that, the software

blinks the LED(s) or sets up light patterns during normal operation, to indicate program

execution progress and/or errors. This serves to reassure most technicians/engineers and some

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users.

1.8THE CONTROL LOOP:

In this design, the software has a loop. The loop calls subroutines. Each subroutine

manages a part of the hardware or software. Interrupts generally set flags, or update counters

that are read by the rest of the software. A simple API disables and enables interrupts. Done

right, it handles nested calls in nested subroutines, and restores the preceding interrupt state in

the outermost enable. This is one of the simplest methods of creating an exocrine.

Typically, there's some sort of subroutine in the loop to manage a list of software

timers, using a periodic real time interrupt. When a timer expires, an associated subroutine is

run, or flag is set. Any expected hardware event should be backed-up with a software timer.

Hardware events fail about once in a trillion times.

State machines may be implemented with a function-pointer per state-machine (in C+

+, C or assembly, anyway). A change of state stores a different function into the pointer. The

function pointer is executed every time the loop runs.

Many designers recommend reading each IO device once per loop, and storing the

result so the logic acts on consistent values. Many designers prefer to design their state

machines to check only one or two things per state. Usually this is a hardware event, and a

software timer. Designers recommend that hierarchical state machines should run the lower-

level state machines before the higher, so the higher run with accurate information.

Complex functions like internal combustion controls are often handled with multi-

dimensional tables. Instead of complex calculations, the code looks up the values. The

software can interpolate between entries, to keep the tables small and cheap.

One major disadvantage of this system is that it does not guarantee a time to respond

to any particular hardware event. Careful coding can easily assure that nothing disables

interrupts for long. Thus interrupt code can run at very precise timings. Another major

weakness of this system is that it can become complex to add new features. Algorithms that

take a long time to run must be carefully broken down so only a little piece gets done each

time through the main loop.

This system's strength is its simplicity, and on small pieces of software the loop is

usually so fast that nobody cares that it is not predictable. Another advantage is that this

system guarantees that the software will run. There is no mysterious operating system to

blame for bad behavior.

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1.9 USER INTERFACES:

Interface designers at PARC, Apple Computer, Boeing and HP minimize the number

of types of user actions. For example, use two buttons (the absolute minimum) to control a

menu system (just to be clear, one button should be "next menu entry" the other button should

be "select this menu entry"). A touch-screen or screen-edge buttons also minimize the types

of user actions.

Another basic trick is to minimize and simplify the type of output. Designs should

consider using a status light for each interface plug, or failure condition, to tell what failed. A

cheap variation is to have two light bars with a printed matrix of errors that they select- the

user can glue on the labels for the language that she speaks.

For example, Boeing's standard test interface is a button and some lights. When you

press the button, all the lights turn on. When you release the button, the lights with failures

stay on. The labels are in Basic English.

Designers use colors. Red defines the users can get hurt- think of blood. Yellow

defines something might be wrong. Green defines everything's OK.

Another essential trick is to make any modes absolutely clear on the user's display. If

an interface has modes, they must be reversible in an obvious way. Most designers prefer thedisplay to respond to the user. The display should change immediately after a user action. If

the machine is going to do anything, it should start within 7 seconds, or give progress reports.

Block Diagram:

Figure 1 block diagram

Intelligent Transportation System is a crucial part of Chinas information construction. With

the increasing city holdings of cars, there are more and more traffic jams, so requirements

are that Intelligent Transportation needs more improvement. The key technology Of

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2x16 LCD

GSM ModemGPSModem

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Intelligent Transportation is Vehicle positioning System, while the key of which is positioning

System. Nowadays the most widely used positioning system is the Global Positioning

System of America (GPS), which is a system consisting 24 satellites whose searching area

embrace the globe. It can ensure that more than 4 satellites will be observed at one time, nomatter what time it is or where you are, thus making sure that they can collect the longitude

and latitude of the view point, and furthermore realizing the function of navigation,

positioning, and time service.

The design of this paper-Vehicle positioning System Based on ARM a

combination of GPS and GSM can upload the information of the vehicle such as the position

and speed to the Monitoring center in time, to make it convenient to control the traffic. Whats

more, users can use the password to track vehicles, for security and anti-robbery, call

Manual / automatic alarm, and check the vehicle position.

Description:

In this project, if we want to identify our vehicle location, we will send a SMS to the

GSM modem which is interfaced with the microcontroller. The GSM modem will receive the

message and switch on GPS Module and receives the position of the vehicle in terms of

latitude and longitude. And the same information will be send back to the predefined number.

The architecture and working theory of this system is introduced in details, and introduces the

vehicle location system which uses the AT89S52 as a control unit to combinative with GPS

and GSM

HARDWARE COMPONENTS DISCRIPTION

Hardware Tools:

ARM7

GPS Module

GSM Modem

BLOCK DIAGRAM DISCRIPTION:

1.10ARM 7(LPC2148)

2.2.1FEATURES OF ARM 7:

It consist of 2/32-bit ports, 32-bit data bus&32-bit address bus.

2/10-bit ADCs &1/10-bitDAcs.

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2 UART s, 2/32 bit timers.

32KB of on-chip RAM, 512KB of ROM, 4GB of external memory.

Single flash sector or full chip erase in 400ms and programming of 256 bytes in 1m

It is a 32 bit RISC.

Its operating voltage is 3.3V.

ARM processor mode supports low power applications.

It supports 16-bit&32-bit instructions.

Crystal oscillator frequency1MHz-60MHz (12MHz).

The ARM architecture as shown in fig 2.2 is based on Reduced Instruction Set

Computer (RISC) principles. The RISC instruction set and related decode mechanism are

much simple than those of Complex Instruction Set Computer(CISC) designs.

This simplicity gives:

A high instruction throughput

An excellent real-time interrupt response

A small, cost-effective, processor macro cell.

The ARM7TDMI processor has two instruction sets:

The 32-bit ARM instruction set

The 16-bit Thumb instruction set.

The ARM7TDMI processor is an implementation of the ARMv4T architecture.

Instruction compression

Microprocessor architectures traditionally have the same width for instructions and

data. In comparison with 16-bit architectures, 32-bit architectures exhibit higher performance

when manipulating 32-bit data and can address a large address space much more efficiently.

16-bit architectures typically have higher code density than 32-bit architectures, but

approximately half the performance

Thumb implements a 16-bit instruction set on a 32-bit architecture to provide:

Higher performance than a 16-bit architecture

Higher code density than a 32-bit architecture.

1.11The Thumb instruction set

The Thumb instruction set is a subset of the most commonly used 32-bit ARM

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instructions. Thumb instructions are each 16 bits long, and have a corresponding 32-bit ARM

instruction that has the same effect on the processor model. Thumb instructions operate with

the standard ARM register configuration, allowing excellent interoperability between ARM

and Thumb states. On execution, 16-bit Thumb instructions are transparently decompressedto full 32-bit ARM instructions in real time without performance loss.

Thumb has all the advantages of a 32-bit core:

32-bit address space

32-bit registers

ARM controller, In Vehicle terminal, as a central

processing unit of the system, ARM embedded system has a critical

influence on overall performance. So introduced by Philips, the 16/32-bit

ARM7 TDMI-S core LPC2148 microcontroller with real-time simulation and

tracking. Support is used. It has 16K bytes of static RAM and 128k

bytes of embedded high speed Flash memory. In the 64-pin package, 46

GPIO can be used. The Conversion Time of 4 10- bit A / D converter can

be as few as 2.44us. It has Real-time clock and watchdog. A maximum

operating frequency of 60MHz of the CPU can be achieved through the

on-chip PL, and the rich on-chip resources can meet the needs of general

industrial control. LPC2129 not only works stably and faster, but also has

dual serial, so is accessible to the plan.

GPS Wireless communication module, this design adapts the current leading GPS

technology and the integrated positioning chip LEADTEK LR9548S. Specifically Designed

for OEM Applications, it is a GPS receiver module with high sensitivity, low power

consumption, and 20 channels. Com- pared with other independent GPS solutions GPS9548

is able to help Users gain and continuously track GPS signals at a very low signal

intensity, which means GPS9548 can be used in the environment where it has never been

thought to be accessible, such as Buildings of the city building, dense forest, garage, and

many indoor environment, with a positioning accuracy of less than 10 meters. With only an

addition of relevant circuit at the periphery, positioning information including time, longitude,

latitude, rate, moving direction, etc, can be output through the serial.

GSM module TC35, Siemens TC35i wireless communication module is used.

Having gained the domestic network card of Radio equipment, it operates in dual-

band GSM900 and GSM1800, with power consumption of 2W and 1W respectively.

The DC power supply ranges from 3.3v to4.8V. The Current consumption is as below

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3.5mA at sleep state, 25mA at leisure state 300m (Average) at launchingstate, and the

maximum is 2.5A.

Combining RF and baseband, this module provides users with a standard ATcommand interface and a fast, secure and reliable transmission of data, voice, SMS and

fax. The Data input / output interface of TC35 is in effect a Serial Asynchronous

Receiver Transmitter. It has fixed parameters and is in line with ITU-T RS232 interface

standard 8 data bits and 1 stop bit, no parity; the baud rate is selectable between 300bps

and 115kbps. The Command Interface of TC35imodule Fully complies with specifications of

GSM07.05 and GSM07.07. It sends standard AT commands through the serial port of a

microprocessor LPC2129 to TC35i module serial port, to fulfill the Locators function

of sending and receiving text messages, therefore realizing the communication with

m o b i l e phone users outside.

Combining RF and baseband, this module provides users with a standard AT

command interface and a fast, secure and reliable transmission of data, voice, SMS and

fax. The Data input / output interface of TC35 is in effect a Serial Asynchronous

Receiver Transmitter. It has fixed parameters and is in line with ITU-T RS232 interface

standard 8 data bits and 1 stop bit, no parity; the baud rate is selectable between 300bps

and 115kbps. The Command Interface of TC35imodule Fully complies with specifications of

GSM07.05 and GSM07.07. It sends standard AT commands through the serial port of a

microprocessor LPC2129 to TC35i module serial port, to fulfill the Locators function

of sending and receiving text messages, therefore realizing the communication with

m o b i l e phone users outside.

GPIO Interface is to be connected with Traffic recorder, Car alarm and security

control. Through that Interface, Microprocessor can have real-time monitoring of vehicles,

circuits, air pressure, temperature, central locking, alarm and other status information, in

order to make response timely GSM module TC35. Siemens TC35i wireless

communication module is used. Having gained the domestic network card of Radio

equipment, it operates in dual-band GSM900 and GSM1800, with power consumption of

2W and 1W respectively. The DC power supply ranges from 3.3v to 4.8V. The

Current consumption is as below 3.5mA at sleep state, 25mA at leisure state 300m

(Average) at launchingstate, and the maximum is 2.5A.

When using GPS to position, each satellite will send to the receiving terminal three

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key messages: Satellite number, satellite position, and time. The receiving terminal store

and use the received information, which is also used to fix the time on the GPS receiver. By

comparing the difference of the time when each satellite signal is received and the time

when the satellite is sent, The GPS receiver calculate the distance from each satellite to thereceiver. When the receiver can contact enough satellites, it can use trigonometric formulas

to calculate the location of the receiver. Three satellites can be able to operate 2D

positioning (longitude and latitude), while four or more can be able to operate 3D positioning

(longitude, latitude, and height). The key indicator of positioning is the accuracy. The

horizontal position accuracy of most Civilian GPS receivers is about 5 to 10m. Using

differential technique, cm- level even mm-level positioning accuracy can be achieved.

A.map matching, the data source of Vehicle positioning System is mainly formed

of Static data (electronic maps) and dynamic data (location data). The role of map matching

in the vehicle positioning system .In practical application, the current civil positioning

technique is far from the accuracy of the level of road width, so it is necessary to match

with the electronic map to achieve good positioning and location service. The basic idea of

map matching is that by matching the positioning coordinates of the vehicle trajectory with

the factorized section of the object on the map, the road that vehicles currently exercise can

be found, and the vehicle tab will be projected onto the road. That can be classified into two

relatively independent processions: One is to find the road that vehicles currently exercise;

the other is to project the vehicle tab onto the road. The map matching done at this

stage is not perfect. The Vehicle Positioning System in practical application shows the

phenomenon of serious zero drift or vehicle "driving" on both sides of the road on map.

Therefore the improvement of Map Matching Algorithm is also the current research focus

in vehicle positioning technology.

3 Data compression / fusion, First and foremost, a vehicle positioning system is

an embedded system, which has some requirements of the size and real-time of the data

processing. So it is necessary to compress the received data of the positioning system.

The ARM7TDMI core is a member of the ARM family of general-purpose 32-bit

Microprocessors. The ARM [4] family offers high performance for very low power

Consumption and small size.

The ARM architecture as shown in fig 2.2 is based on Reduced Instruction Set Computer

(RISC) principles. The RISC instruction set and related decode mechanism are much simple

than those of Complex Instruction Set Computer(CISC) designs.

This simplicity gives:

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A high instruction throughput

An excellent real-time interrupt response

A small, cost-effective, processor macro cell.

1.12 The instruction pipelineThe ARM7TDMI core uses a pipeline to increase the speed of the flow of instructions

to the processor. This enables several operations to take place simultaneously, and the

processing and memory systems to operate continuously.

A three-stage pipeline is used as shown in fig 2.1, so instructions are executed in three

stages:

Fetch

Decode Execute.

Figure 2 Instruction pipeline

During normal operation, while one instruction is being executed, its successor is

being decoded, and a third instruction is being fetched from memory. The program counter

points to the instruction being fetched rather than to the instruction being executed. This is

important because it means that the Program Counter (PC) value used in an executing

instruction is always two instructions ahead of the address.

Memory access

The ARM7TDMI core has Von Neumann architecture, with a single 32-bit data bus

carrying both instructions and data. Only load, store, and swap instructions can access data

from memory.

Data can be:

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FIQ SUPERVISOR ABORT IRQ UNDEFINED

R0 R0 R0 R0 R0 R0

R1 R1 R1 R1 R1 R1

R2 R2 R2 R2 R2 R2

R3 R3 R3 R3 R3 R3

R4 R4 R4 R4 R4 R4

R5 R5 R5 R5 R5 R5

R6 R6 R6 R6 R6 R6

R7 R7 R7 R7 R7 R7

R8 R8_FIQ R8 R8 R8 R8

R9 R9_FIQ R9 R9 R9 R9

R10 R10_FIQ R10 R10 R10 R10

R11 R11_FIQ R11 R11 R11 R11

R12 R12__FIQ R12 R12 R12 R12

R13 R13_FIQ R13_SVC R13_ABT R13_IRQ R13_UND

R14 R14_FIQ R14_SVC R14_ABT R14_IRQ R14_UND

R15(PC) R15(PC) R15(PC) R15(PC) R15(PC) R15(PC)

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Figure 3 ARM7TDMI processor block diagram

TABLE 1 UART SERIAL COMMUNICATION

CPSR CPSR CPSR CPSR CPSR CPSR

SPSR_FIQ SPSR_SVC SPSR_ABT SPSR_IRQ SPSR_UND

The ARM7TDMI core has four basic types of memory cycle:

Idle cycle

Non sequential cycle

Sequential cycle

Coprocessor registers transfer cycle.

4.1.3Architecture

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The ARM7TDMI processor has two instruction sets:

The 32-bit ARM instruction set

The 16-bit Thumb instruction set.

The ARM7TDMI processor is an implementation of the ARMv4T architecture.

Instruction compression

Microprocessor architectures traditionally have the same width for instructions and

data. In comparison with 16-bit architectures, 32-bit architectures exhibit higher performance

when manipulating 32-bit data and can address a large address space much more efficiently.

16-bit architectures typically have higher code density than 32-bit architectures, but

approximately half the performance.

Thumb implements a 16-bit instruction set on a 32-bit architecture to provide:

Higher performance than a 16-bit architecture

Higher code density than a 32-bit architecture.

The Thumb instruction set

The Thumb instruction set is a subset of the most commonly used 32-bit ARM

instructions. Thumb instructions are each 16 bits long, and have a corresponding 32-bit ARM

instruction that has the same effect on the processor model. Thumb instructions operate with

the standard ARM register configuration, allowing excellent interoperability between ARM

and Thumb states. On execution, 16-bit Thumb instructions are transparently decompressed

to full 32-bit ARM instructions in real time without performance loss.

Thumb has all the advantages of a 32-bit core:

32-bit address space

32-bit registers

32-bit shifter, and Arithmetic Logic Unit(ALU)

32-bit memory transfer.

Thumb therefore offers a Long Branch range, powerful arithmetic operations, and a

large address space. Thumb code is typically 65% of the size of ARM code, and provides

160% of the performance of ARM code when running from a 16-bit memory system.

Thumb, therefore, makes the ARM7TDMI core ideally suited to embedded applications with

restricted memory bandwidth, where code density and footprint is important.

The availability of both 16-bit Thumb and 32-bit ARM instruction sets gives

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designers the flexibility to emphasize performance or code size on a subroutine level,

according to the requirements of their applications. For example, critical loops for

applications such as fast interrupts and DSP algorithms can be coded using the full ARM

instruction set then linked with Thumb code.

4.1.4Software Development

In this module we will be using an Integrated Development Environment from Kiel

Electronic. This IDE is called u VISION (pronounced Micro Vision) and versions already

exist for other popular microcontrollers including the 8051 and the In fine on C16X family. u

VISION successfully integrates project management, editor, compiler and debugger in one

seamless front-end. Although we are concentrating on the LPC2000 family in this book, the

Kiel ARM tools can be used for any other ARM7 based microcontroller.

The Compiler

The u VISION development environment can be used with several different compiler

tools. These include the ARM ADS compiler, the GNU compiler and Kiels own ARM

compiler.

The Kiel u VISION (u VISION) IDE is designed to support several compilers, the

Gnu C compiler, The ARM development suite and the Kiel ARM compiler. Before compiling

make sure you have the GNU compiler selected. This is done by activating the project

workspace; right clicking and selecting manage components. In this dialog select the

Folders/extensions tab and make sure the Kiel ARM tools box is selected.

CHAPTER 2

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KEIL SOFTWARE

Keil Software

Installing the Keil software on a Windows PC

Insert the CD-ROM in your computers CD drive

On most computers, the CD will auto run, and you will see the Keil installation

menu. If the menu does not appear, manually double click on the Setup icon, in the

root directory: you will then see the Keil menu.

On the Keil menu, please select Install Evaluation Software. (You will not require a

license number to install this software).

Follow the installation instructions as they appear.

Loading the Projects

The example projects for this book are NOT loaded automatically when you install the Keil compiler.

These files are stored on the CD in a directory /Pont. The files are arranged by chapter: for

example, the project discussed in Chapter 3 is in the directory /Pont/Ch03_00-Hello.

Rather than using the projects on the CD (where changes cannot be saved), please copy the

files from CD onto an appropriate directory on your hard disk.

Note: you will need to change the file properties after copying: file transferred from the CD

will be read only.

Configuring the Simulator

Open the Keil Vision2

Go to Project Select Device for Target Target1

Now we need to check the oscillator frequency:

Go to project Options for Target Target1

Make sure that the oscillator frequency is 12MHz.

Building the Target

4.1.5Kiel Toolset

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Step1: Open Kiel UVISION3.

Step2: Add user manual.

Step3: Create new file.

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step4: Select LPC2148.

step5: Add code to source file and build target

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step6: Using simulator.

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Step7: Using PHILIPS LPC2000 Flash Utility dump the hex file of the code

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CHAPTER3

GSM and GPS

GSM/GPRS module is used to establish communication between a computer and a

GSM-GPRS system. Global System for Mobile communication (GSM) is an architecture

used for mobile communication in most of the countries. Global Packet Radio Service

(GPRS) is an extension of GSM that enables higher data transmission rate. GSM/GPRS

module consists of a GSM/GPRS modem assembled together with power supply circuit

and communication interfaces (like RS-232, USB, etc) for computer. The MODEM is the

soul of such modules.

Fig 3 GSM/GPRS module

3.1 Wireless MODEMs

Wireless MODEMs are the MODEM devices that generate, transmit or decode data

from a cellular network, for establishing communication between the cellular network and the

computer. These are manufactured for specific cellular network (GSM/UMTS/CDMA) or

specific cellular data standard (GSM/UMTS/GPRS/EDGE/HSDPA) or technology

(GPS/SIM). Wireless MODEMs like other MODEM devices use serial communication to

interface with and need Hayes compatible AT commands for communication with the

computer (any microprocessor or microcontroller system).

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Fig 5 cellular data standard MODEM

3.2 Applications of GSM/GPRS moduleThe GSM/GPRS module demonstrates the use of AT commands. They can feature all

the functionalities of a mobile phone through computer like making and receiving calls, SMS,

MMS etc. These are mainly employed for computer based SMS and MMS services.

3.3 AT Commands

AT commands are used to control MODEMs. AT is the abbreviation for Attention.

These commands come from Hayes commands that were used by the Hayes smart modems.

The Hayes commands started with AT to indicate the attention from the MODEM. The dial

up and wireless MODEMs (devices that involve machine to machine communication) need

AT commands to interact with a computer. These include the Hayes command set as a subset,

along with other extended AT commands.

AT commands with a GSM/GPRS MODEM or mobile phone can be used to access

following information and services:

1. Information and configuration pertaining to mobile device or MODEM and SIM card.

2. SMS services.

3. MMS services.

4. Fax services.

5. Data and Voice link over mobile network.

The Hayes subset commands are called the basic commands and the commands

specific to a GSM network are called extended AT commands.

GSM (Global System for Mobile communications) is a cellular network, which means

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that mobile phones connect to it by searching for cells in the immediate vicinity. GSM

networks operate in four different frequency ranges. Most GSM networks operate in the 900

MHz or 1800 MHz bands. Some countries in the Americas use the 850 MHz and 1900 MHz

bands because the 900 and 1800 MHz frequency bands were already allocated.The rarer 400 and 450 MHz frequency bands are assigned in some countries, where

these frequencies were previously used for first-generation systems.GSM-900 uses 890915

MHz to send information from the mobile station to the base station (uplink) and 935960

MHz for the other direction (downlink), providing 124 RF channels (channel numbers 1 to

124) spaced at 200 kHz. Duplex spacing of 45 MHz is used. In some countries the GSM-900

band has been extended to cover a larger frequency range. This 'extended GSM', E-GSM,

uses 880915 MHz (uplink) and 925960 MHz (downlink), adding 50 channels (channel

numbers 975 to 1023 and 0) to the original GSM-900 band. Time division multiplexing is

used to allow eight full-rate or sixteen half-rate speech channels per radio frequency channel.

There are eight radio timeslots (giving eight burst periods) grouped into what is called a

TDMA frame. Half rate channels use alternate frames in the same timeslot. The channel data

rate is 270.833 kbit/s, and the frame duration is 4.615 ms.

3.4 GSM Advantages:

GSM also pioneered a low-cost, to the network carrier, alternative to voice calls, the

Short t message service (SMS, also called "text messaging"), which is now supported on

other mobile standards as well. Another advantage is that the standard includes one

worldwide Emergency telephone number, 112. This makes it easier for international travelers

to connect to emergency services without knowing the local emergency number.

3.5 GPS

Long before Global Positioning System (GPS) arrived, researchers worked hard to

arrive at a feasible solution to aid travelers from getting lost. Earlier, travelers used to rely on

elaborate maps to track and monitor the route to their destination. But today, GPS technologyhas ensured hassle free trips and increased safety for vehicle owners. The figure below

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illustrates a GPS satellite in orbit.

Fig 6 GPS satellite in orbit

Introduction

GPS technologyGPS works all across the world and in all weather conditions, thus helping users track

locations, objects, and even individuals! GPS technology can be used by any person if they

have a GPS receiver. A GPS receiver calculates its position by carefully timing the signals

sent by the constellation of GPS satellites high above the Earth. Each satellite continually

transmits messages containing the time the message was sent, a precise orbit for the satellite

sending the message (the ephemeris), and the general system health and rough orbits of all

GPS satellites (the almanac). These signals travel at the speed of light through outer space,

and slightly slower through the atmosphere. The receiver uses the arrival time of each

message to measure the distance to each satellite, from which it determines the position of the

receiver (conceptually the intersection of spheres - see trilateration ) The resulting

coordinates are converted to more user-friendly forms such as latitude and longitude, or

location on a map, then displayed to the user.

It might seem that three satellites would be enough to solve for a position, since space

has three dimensions. However, a three satellite solution requires the time be known to a

nanosecond or so, far better than any non-laboratory clock can provide. Using four or more

satellites allows the receiver to solve for time as well as geographical position, eliminating

the need for a super accurate clock. In other words, the receiver uses four measurements tosolve for four variables: x, y, z, and t. While many GPS applications have no particular use

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for this (very accurate) time, it is used in some GPS applications such as time transfer, and it

is the only variable of interest in some applications, such as traffic signal timing.

Although four satellites are required for normal operation, fewer may be needed in

some special cases. If one variable is already known (for example, a ship or plane mayalready know its altitude), a receiver can determine its position using only three satellites.

Also, in practice, receivers use additional clues (Doppler shift of satellite signals, last known

position, dead reckoning, inertiral navigation, and so on) to give degraded answers when

fewer than four satellites are visible.

3.6 Position calculation:

To provide an introductory description of how a GPS receiver works, errors will be

ignored in this section. Using messages received from a minimum of four visible satellites, a

GPS receiver is able to determine the satellite positions and time sent.

The x, y, and z components of position and the time sent are designated as

where the subscript i denotes the satellite number and has the value 1, 2, 3, or

4. Knowing the indicated time the message was received , the GPS receiver can compute

the indicated transit time, . of the message.

Assuming the message traveled at the speed of light, c, the distance travelled, can

be computed as . Knowing the distance from GPS receiver to a satellite

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Fig 6.1 system segmentation

System segmentation

The current GPS consists of three major segments. These are the space segment (SS),

a control segment (CS), and a user segment (US).

Space segment

A visual example of the GPS constellation in motion with the Earth rotating, Notice how the

number of satellites in view from a given point on the Earth's surface, in this example at

45N, changes with time.

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The space segment (SS) comprises the orbiting GPS satellites or Space Vehicles (SV)

in GPS parlance. The GPS design originally called for 24 SVs, eight each in three circular

orbital planes, but this was modified to six planes with four satellites each. The orbital planes

are centered on the Earth, not rotating with respect to the distant stars. The six planes haveapproximately 55 inclination (tilt relative to Earth's equator) and are separated by 60 right

ascension of the ascending node (angle along the equator from a reference point to the orbit's

intersection). The orbits are arranged so that at least six satellites are always within line of

sight from almost everywhere on Earth's surface.

Orbiting at an altitude of approximately 20,200 kilometers (12,600 miles or 10,900

nautical miles; orbital radius of 26,600 km (16,500 mi or 14,400 NM)), each SV makes two

complete orbits each sidereal day. The ground track of each satellite therefore repeats each

(sidereal) day. This was very helpful during development, since even with just four satellites,

correct alignment means all four are visible from one spot for a few hours each day. For

military operations, the ground track repeat can be used to ensure good coverage in combat

zones.

As of March 2008, there are 31 actively broadcasting satellites in the GPS

constellation. The additional satellites improve the precision of GPS receiver calculations by

providing redundant measurements. With the increased number of satellites, the constellation

was changed to a non-uniform arrangement. Such an arrangement was shown to improve

reliability and availability of the system, relative to a uniform system, when multiple

satellites fail.

Some reports in 2008 indicated that the 32nd satellite was causing difficulties for

some GPS receivers.

Control segment

The flight paths of the satellites are tracked by US Air Force monitoring stations in

Hawaii, Kwajalein, Ascension Island, Diego Garcia, and Colorado Springs, Colorado, along

with monitor stations operated by the National Geospatial-Intelligence Agency (NGA). The

tracking information is sent to the Air Force Space Command's master control station at

Schriever Air Force Base in Colorado Springs, which is operated by the 2nd Space

Operations Squadron (2 SOPS) of the United States Air Force (USAF). Then 2 SOPS

contacts each GPS satellite regularly with a navigational update (using the ground antennas at

Ascension Island, Diego Garcia, Kwajalein, and Colorado Springs). These updates

synchronize the atomic clocks on board the satellites to within a few nanoseconds of each

other, and adjust the ephemeris of each satellite's internal orbital model. The updates are

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created by a Kalman filter which uses inputs from the ground monitoring stations, space

weather information, and various other inputs.

Satellite maneuvers are not precise by GPS standards. So to change the orbit of a

satellite, the satellite must be marked 'unhealthy', so receivers will not use it in theircalculation. Then the maneuver can be carried out, and the resulting orbit tracked from the

ground. Then the new ephemeris is uploaded and the satellite marked healthy again.

User segment

PS receivers come in a variety of formats, from devices integrated into cars, phones,

and watches, to dedicated devices such as those shown here from manufacturers Trimble,

Garmin and Leica (left to right).

The user's GPS receiver is the user segment (US) of the GPS. In general, GPS

receivers are composed of an antenna, tuned to the frequencies transmitted by the satellites,

receiver-processors, and a highly-stable clock (often a crystal oscillator). They may also

include a display for providing location and speed information to the user. A receiver is often

described by its number of channels: this signifies how many satellites it can monitor

simultaneously. Originally limited to four or five, this has progressively increased over the

years so that, as of 2007, receivers typically have between 12 and 20 channels.

Space segment The satellites are the heart of the Global positioning system which helps to

locate the position by broadcasting the signal used by the receiver. The signals are blocked

when they travel through buildings, mountains, and people. To calculate the position, the

signals of four satellites should be locked. You need to keep moving around to get clear

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reception.

User segment This segment includes military and civilian users. It comprises of a sensitive

receiver which can detect signals (power of the signal to be less than a quadrillionth power ofa light bulb) and a computer to convert the data into useful information. GPS receiver helps

to locate your own position but disallows you being tracked by someone else.

Control segment This helps the entire system to work efficiently. It is essential that the

transmission signals have to be updated and the satellites should be kept in their appropriate

orbits.

Working Principle:

The GPS satellites rotate twice a day around the earth in a specific orbit. These

satellites transmit signal information to earth. This signal information is received by the GPS

receiver in order to measure the users correct position. The GPS receiver compares the time

a satellite transmits the signal with the time the signal is received. The time difference

calculated enables us to know the distance of the satellite. By measuring the distance of few

more satellites, the users position can be verified and displayed on the units electronic map.

To measure 2D position and track movement, the GPS receiver must lock the signal of three

satellites. The receiver can measure 3D position (latitude, longitude and altitude) if the GPS

receiver locks the signal of four or more satellites.

On determining the position of the user, the unit of GPS can measure speed, trip

distance, bearing, distance to destination, tack, time of sunrise and sunset, etc.

Types of GPS receivers

The three types of GPS receivers that offer different level of accuracy, and have different

necessity to obtain the accuracies are:

Coarse Acquisition (C/A) code receivers These receivers offer 1-5 meter GPS

position accuracy with differential correction. With an occupation time of 1 second, these

receivers offer 1-5 meter GPS position accuracy. The GPS position accuracies can be within1-3 meters consistently if the occupation time is long.

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Carrier Phase receivers These receivers offer 10-30 meter GPS position accuracy

with differential correction. The waves that carry C/A signal are counted to calculate the

distance between the satellite and the receiver. High occupation time is required to obtainposition accuracy.

Dual Frequency receivers These receivers offer sub-centimeter GPS position

accuracy with differential correction. These receivers accept signals from the satellites on two

different frequencies to find out accurate position.

Note: Differential correction is a method to compare GPS data collected in the field to the

GPS data collected at a known point.

History

GPS was initially meant for military applications and was built by the American

Department of Defense (DOD) in 1978. It was originally called NAVSTAR and was

introduced with the launch of the first satellite.

Today, around thirty fully operational satellites orbit the earth covering a distance of

20200 km. These GPS satellites transmit signals which help locate the precise location of a

GPS receiver. The latest in efficient satellite technology ensures that the GPS signal can be

used without any fee by any individual in possession of a GPS receiver.

The predecessor of GPS used to be fixed radio stations spread across the globe in

known locations. First, a master station sends out signals after which the slave stations across

the globe start to respond. The slave stations send out these signals after a precise amount of

time. The receivers then start to evaluate the time delay between the reception of the master

and slave signals, thus determining a position relative to the slave stations.

Fixed radio station broadcasting was a problem for the military. This is the main

reason why Transit, the first navigation satellite, was introduced in the 1960s. The location

was determined with the help of a receiver, which calculated the Doppler Effect on the

frequency broadcasted by the satellite to the frequency actually received. After this, the

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receiver closest to the satellite would get information and subsequent readings would

precisely single out a location relative to the position of the satellite.

Modern satellites work differently to determine exact positions. A satellite signal

would include the satellites position and the time of signal transmission. With this crucialinformation, the ground unit would be able to successfully locate a target swiftly and

efficiently. Every satellite signal places the ground unit on a sphere from the satellite. The

location of the GPS receiver is then identified as the intersection of the spheres (for additional

satellite signals).

Latest/Current Research and Key developments

In the mobile phone domain, GPS receivers are very much in demand today. In a few years

from now, all GSM phones are expected to be fitted with superior GPS technology to help the

user in navigation. This superior GPS technology will also help track other GPS-mobile

enabled users. For example, anxious parents can keep a tab on the movements of their

children. It also helps to keep track of individuals working in high-risk areas.

Another important feature is the GPS-enabled theft-protection systems that are very

much in demand these days. This helps motorcycle and automobile manufacturers to locate

stolen vehicles with pinpoint accuracy.

A big boost is provided to computer users in the form of Bluetooth GPS receivers.

These receivers score over traditional connections because a cable is not required.

GPS is also being introduced into supply chains, to ensure that all goods are transported

without hassles and are free from theft.

Problems being faced today

The most common problem that arises with the GPS system is accuracy. Accuracy

depends on the signal that is sent by the time unit. The accuracy gets disturbed if the time is

off in the GPS unit. The time and calculations are affected when it encounters rough

atmospheric conditions. Inaccuracy occurs when a signal is bounced back from mountains,

skyscrapers etc.

Another problem is related to its position that gets updated every twelve minutes.

Once the signal has reached the updated time, the satellite is unable to know the correct

location and can make calculation on based on the wrong information. This kind of errors isunavoidable.

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Applications

This technique was initially developed for military applications. During 1980, the

government decided to make it available for the civilian use as well. GPS has become an

efficient tool in the field of scientific use, commerce, surveillance and tracking.

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CHAPTER 4

CIRCUIT DIAGRAM

Figure 7 Circuit Diagram

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SNOP SHORT:

4.1 DISCRIPTION OF CIRCUIT DIAGRAM

MAX 232:

A standard serial interface for PC, RS232C, requires negative logic, i.e., logic 1 is -3V

to -12V and logic 0 is +3V to +12V. To convert TTL logic, say, TxD and RxD pins of the

microcontroller thus need a converter chip. A MAX232 chip has long been using in many

microcontrollers boards. It is a dual RS232 receiver / transmitter that meets all RS232

specifications while using only +5V power supply. It has two onboard charge pump voltage

converters which generate +10V to -10V power supplies from a single 5V supply. It has four

level translators, two of which are RS232 transmitters that convert TTL/CMOS input levels

into +9V RS232 outputs. The other two level translators are RS232 receivers that convert

RS232 input to 5V. Typical MAX232 circuit is shown below.

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Fig 8 MAX232 pin diagram

1. Operates With Single 5-V Power Supply

2. Lin BiCMOSE Process Technology

3. Two Drivers and Two Receivers

4. 30-V Input Levels

5. Low Supply Current. 8 mA Typical

6. Meets or Exceeds TIA/EIA-232-F and ITU Recommendation V.28

7. Designed to be Interchangeable With

DESCRIPTION:

The MAX232 is a dual driver/receiver that includes a capacitive voltage generator to

supply TIA/EIA-232-F voltage levels from a single 5-V supply. Each receiver convertsTIA/EIA-232-F inputs to 5-V TTL/CMOS levels. These receivers have a typical threshold of

1.3 V, a typical hysterics of 0.5 V, and can accept +/-30-V inputs. Each driver converts

TTL/CMOS input levels into TIA/EIA-232-F levels.

LOGIC DIAGRAM (POSITIVE LOGIC):

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Figure 8.1 LOGIC DIAGRAM OFMAX232

4.2 MAX232:

The MAX232 is an integrated circuitthat converts signals from an RS-232 serial port

to signals suitable for use in TTL compatible digital logic circuits. The MAX232 is a dual

driver/receiver and typically converts the RX, TX, CTS and RTS signals.

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

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

implementing RS-232 in devices that otherwise do not need any voltages outside the 0 V to

+ 5 V range, as power supply design does not need to be made more complicated just for

driving the RS-232 in this case.

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

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

0.5 V.

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

operate at higherbaud rates and can use smaller external capacitors 0.1 F in place of the

1.0 f capacitors used with the original device.

RS-232 BASICS:

RS-232 (Recommended Standard 232) is a standard for serial binary data signals

connecting between a DTE (Data terminal equipment) and a DCE (Data Circuit-terminating

Equipment).

VOLTAGE LEVELS:

The RS-232 standard defines the voltage levels that correspond to logical one and

logical zero levels. Valid signals are plus or minus 3 to 25 volts. The range near zero volts is

not a valid RS-232 level; logic one is defined as a negative voltage, the signal condition is

called marking, and has the functional significance of OFF. Logic zero is positive; the signal

condition is spacing, and has the function ON.

So a Logic Zero represented as +3V to +25V and Logic One represented as -3V to -25V.

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RS-232 Level Converters:

Usually all the digital ICs work on TTL or CMOS voltage levels which cannot be

used to communicate over RS-232 protocol. So a voltage or level converter is needed which

can convert TTL to RS232 and RS232 to TTL voltage levels.

The most commonly used RS-232 level converter is MAX232. This IC includes charge pump

which can generate RS232 voltage levels (-10V and +10V) from 5V power supply. It also

includes two receiver and two transmitters and is capable of full-duplex UART/USART

communication.

A charge pump is a kind ofDC to DC converterthat uses capacitors as energy storage

elements to create either a higher or lower voltage power source. Charge pump circuits are

capable of high efficiencies, sometimes as high as 90-95% while being electrically simple

circuits. Charge pumps use some form of switching device(s) to control the connection of

voltages to the capacitor. For instance, to generate a higher voltage, the first stage involves

the capacitor being connected across a voltage and charged up. In the second stage, the

capacitor is disconnected from the original charging voltage and reconnected with its

negative terminal to the original positive charging voltage. Because the capacitor retains the

voltage across it (ignoring leakage effects) the positive terminal voltage is added to the

original, effectively doubling the voltage. The pulsing nature of the higher voltage output istypically smoothed by the use of an output capacitor.

This is the charge pumping action, which typically operates at tens ofkilohertz up to

several megahertz to minimize the amount of capacitance required. The capacitor used as the

charge pump is typically known as the "flying capacitor". Another way to explain the

operation of a charge pump is to consider it as the combination of a DC to AC converter (the

switches) followed by a voltage multiplier.

The voltage is load-dependent; higher loads result in lower average voltages. Chargepumps can double voltages, triple voltages, halve voltages, invert voltages, fractionally

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multiply or scale voltages such as x3/2, x4/3, x2/3, etc. and generate arbitrary voltages,

depending on the controller and circuit topology.

The term 'charge pump' is also used in phase-locked loop (PLL) circuits. This is a

completely different application. In a PLL the phase difference between the reference signal(often from a crystal oscillator) and the output signal is translated into two signals - UP and

DN. The two signals control switches to steer current into or out of a capacitor, causing the

voltage across the capacitor to increase or decrease. In each cycle, the time during which the

switch is turned on is proportional to the phase difference; hence the charge delivered is

dependent on the phase difference also. The capacitor acts to smooth out abrupt changes on

the voltage and to ensure the PLL's closed-loop stability. The voltage on the capacitor is used

to tune a voltage-controlled oscillator (VCO), generating the desired output signal frequency.

The charge pump in a PLL design is constructed in integrated-circuit (IC) technology,

consisting of pull-up, pull-down transistors and on-chip capacitors and resistors.

4.3 IMPLEMENTATION PROCEDURE:

Intelligent Transportation System is a crucial part of Chinas information construction.

With the increasing city holdings of cars, there are more and more traffic jams, so

requirements are that Intelligent Transportation needs more improvement. The key

technology Of Intelligent Transportation is Vehicle positioning System, while the key of

which is positioning System. Nowadays the most widely used positioning system is the

Global Positioning System of America (GPS), which is a system consisting 24 satellites

whose searching area embrace the globe. It can ensure that more than 4 satellites will be

observed at one time, no matter what time it is or where you are, thus making sure that they

can collect the longitude and latitude of the view point, and furthermore realizing the

function of navigation, positioning, and time service.

The design of this paper-Vehicle positioning System Based on ARMa combination of

GPS and GSM can upload the information of the vehicle such as the position and speed to

the Monitoring center in time, to make it convenient to control the traffic. Whats more,

users can use the password to track vehicles, for security and anti-robbery, call Manual /

automatic alarm, and check the vehicle position.

When using GPS to position, each satellite will send to the receiving terminal three key

messages: Satellite number, satellite position, and time. The receiving terminal store anduse the received information, which is also used to fix the time on the GPS receiver. By

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comparing the difference of the time when each satellite signal is received and the time

when the satellite is sent, The GPS receiver calculate the distance from each satellite to

the receiver. When the receiver can contact enough satellites, it can use trigonometric

formulas to calculate the location of the receiver. Three satellites can be able to operate2D positioning (longitude and latitude), while four or more can be able to operate 3D

positioning (longitude, latitude, and height). The key indicator of positioning is the

accuracy. The horizontal position accuracy of most Civilian GPS receivers is about 5 to

10m. Using differential technique, cm- level even mm-level positioning accuracy can be

achieved.

ARM controller: In Vehicle terminal, as a central processing unit of the system,

ARM embedded system has a critical influence on overall performance. So introduced

by Philips, the 16/32-bit ARM7 TDMI-S core LPC2129 microcontroller with real-time

simulation and tracking. Support is used. It has 16K bytes of static RAM and 128k

bytes of embedded high speed Flash memory. In the 64-pin package, 46 GPIO can be

used. The Conversion Time of 4 10- bit A / D converter can be as few as 2.44us. It has

Real-time clock and watchdog. A maximum operating frequency of 60MHz of the CPU

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can be achieved through the on-chip PL, and the rich on-chip resources can meet the

needs of general industrial control. LPC2129 not only works stably and faster, but also has

dual serial, so is accessible to the plan.

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CHAPTER 5

ADVANTAGES AND DISADVANTAGES

Advantages:

Reduced fuel costs.

Improved driver efficiency and productivity.

Route Optimization & Journey Planning.

Vehicle insurance premium discounts.

Prevention of employee mileage and timesheet inaccuracies and abuse.

Reduced time and expenditure on phone calls. Improved Customer Service.

Reduced administration tasks for drivers and office staff.

Improved fleet optimization. Increased vehicle security & driver safety.

Improved ability to monitor employee compliance with road related Health & Safety,

Duty of Care and Working Time Directive legislation.

Improved response time to customer requests leading to a competitive advantage.

Disadvantages:

1. Network of SIM & SIM balance

Vehicle tracking a great piece of technology but there are some disadvantages to it.

Not many, but there are some and if you are going to invest in a tracking system then you

should be aware of these disadvantages.

2) To get a vehicle tracking system which can really help your business save money,

increase productivity, help with customer service, lower insurance premiums, assist with

health, keep tabs on staff and safety issues and increase profits you will need to make a large

investment.

3) Tracking systems can cause some resentment amongst your staff and sometimes there

can be complaints of an invasion of privacy.

4) Like any technology it can sometimes go wrong and let you down. Once you become to

rely on it this can be a problem and cause stress within the business.

5) If the company that supplies the vehicle tracking goes bankrupt you could be left

paying for a tracking system that no longer provides you with the service. This is why you

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need to be very careful who you buy vehicle tracking from. Vet the company and their credit

record carefully. Another option is pay as you go tracking, its more expensive per month, but

it avoids the problem of getting a lease and you do not have the same initial outlay or

commitment. Read this article for more information on pay as you go tracking

CHAPTER 6APPLICATIONS

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Fleet management: When managing a fleet of vehicles, knowing the real-time

location of all drivers allows management to meet customer needs more efficiently.

Whether it is delivery, service or other multi-vehicle enterprises, drivers now only

need a mobile phone with telephony or Internet connection to be inexpensivelytracked by and dispatched efficiently.

Asset tracking: Companies needing to track valuable assets for insurance or other

monitoring purposes can now plot the real-time asset location on a map and closely

monitor movement and operating status.

Field service management: Companies with a field service workforce for services

such as repair or maintenance, must be able to plan field workers time, schedule

subsequent customer visits and be able to operate these departments efficiently.Vehicle tracking allows companies to quickly locate a field engineer and dispatch the

closest one to meet a new customer request or provide site arrival information.

Field sales: Mobile sales professionals can access real-time locations. For example, in

unfamiliar areas, they can locate themselves as well as customers and prospects, get

driving directions and add nearby last-minute appointments to itineraries. Benefits

include increased productivity, reduced driving time and increased time spent with

customers and prospects.

Trailer tracking: Haulage and Logistics companies often operate lorries with

detachable load carrying units. The part of the vehicle that drives the load is known as

the cab and the load carrying unit is known as the trailer. There are different types of

trailer used for different applications, e.g., flat bed, refrigerated, curtain sider, box

container.

Surveillance: A tracker may be placed on a vehicle to follow the vehicle's

movements.

Transit tracking: This is the temporary tracking of assets or cargoes from one point to

another. Users will ensure that the assets do not stop on route or do a U-Turn in order

to ensure the security of the assets.

Vehicle tracking systems are widely used worldwide. Components come in various shapes

and forms but most utilize GPS technology and SMS services. While most will offer real-

time tracking, others record real time data and store it to be read, similar to data loggers.

Systems like these track and record and allow reports after certain points have

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CHAPTER 7

CONCLUSION AND FUTURE SCOPE

Vehicle increasingly important in large cities and it is more secured than other

systems. Now a days vehicle Theft is rapidly increasing, with this we can have a good

control in it. The vehicle can be turned off by only with a simple SMS .Since, now a days the

cost of the vehicles are increasing they will not step back to it, This setup can be made more

interactive by adding a display to show some basic information about the vehicle and also

add emergency numbers which can be used in case of emergency .Upgrading this setup is

very easy which makes it open to future requirements without the everything from scratch,

which also makes it more efficient

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CHAPTER 8

REFERENCE

[1] Ezell, Barry, "Scenarios One and Two: Source to No 1 PS to No 1 Tank to No 2 PS to No2 tank (High level) for a Master-Slave SCADA System", SCADA Consultants, SCADA Mail

List, [email protected] (August 1997).

[2] Lambert, Robert, "An Interview in Newport News, Va.", President, Automation, Inc., June

12, 1997.

[3] National Security Telecommunications Advisory Committee (NSTAC), "Information

Assurance Task Force

[4] Risk Assessment", http://www.ncs.gov/n5_hp/reports/EPRA.html(October 10, 1997).

Rockwell Automation SCADA System Selection Guide Allen-Bradley, Publication AG-2.1.

1998.

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CHAPTER 9

APENDEX

CODE

#include

void delay()

{

unsigned int i;

for(i=0;i


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void disp(unsigned int i)

{

i


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while(!(U1LSR&0X01));

x=U1RBR;

if(x!='G')

{

goto back1;

}


x=U1RBR;

if(x!='G')

{

goto back1;

}


x=U1RBR;

if(x!='A')

{

goto back1;

}

for(i=0;i


49/55

lo[i]=U1RBR;

}

cmd(0x01);

cmd(0x80);

for(i=0;i


50/55



s=U0RBR;

U0THR=0x0A;



s=U0RBR;

for(i=0;i


51/55

{

disp(lo[i]);

U0THR=lo[i];



s=U0RBR;

}

U0THR=0x1A;



s=U0RBR;

for(i=0;i


52/55

IODIR1=0x03FF0000;

IODIR0 = 0x00007070;

U0LCR = 0x83;

U0DLL = 0x61;

U0DLM = 0x00;

U0LCR = 0x03;

U1LCR = 0x83;

U1DLL = 0x61;

U1DLM = 0x00;

U1LCR = 0x03;

lcd_init();

for(i=0;i


53/55

cmd(0x01);

cmd(0x80);

while(1)

{

cmd(0x01);

cmd(0x80);


x=U0RBR;

while(x!=',')

{


x=U0RBR;

}


z=U0RBR;//disp(z);

for(i=0;i


54/55

U0THR=0x0D;



s=U0RBR;

U0THR=0x0A;



s=U0RBR;

while(x!='*')

{


x=U0RBR;

}


s=U0RBR;

if(s=='G')

{

gps();

delay();

}

for(i=0;i


55/55

U0THR=z;



s=U0RBR;

U0THR=0x0D;



s=U0RBR;

U0THR=0x0A;



s=U0RBR;

}

}

Documents

B 11 Documentation