CHAPTER 1

INTRODUCTION

1.1 EMBEDDED SYSTEM

An embedded system is a computer syste m with a dedicated function within a

larger mechanical or electrical system, often with real-time computing constraints.t is

embedded as part of a complete device often including hardware and mechanical

parts. By contrast, a general-purpose computer, such as a personal computer (PC), is

designed to be flexible and to meet a wide range of end-user needs. Embedded

systems control many devices in common use today.

Embedded systems contain processing cores that are either microcontrollers or

digital signal processors (DSP).A processor is an important unit in the embedded

system hardware. It is the heart of the embedded system. Embedded systems are

widespread in consumer, cooking, industrial, commercial and military applications.

Telecommunications systems employ numerous embedded systems from

telephone switches for the network to mobile phones at the end-user. Computer

networking uses dedicated routers and network bridges to route data. Embedded

systems are used in transportation, fire safety, safety and security, medical

applications and life critical systems as these systems can be isolated from hacking

and thus be more reliable. For fire safety, the systems can be designed to have greater

ability to handle higher temperatures

1.2COMMON FEATURES OF EMBEDDED SYSTEM

Embedded systems are designed to do a specific task, unlike general-purpose

computers .It does not look like a computer - there may not be a full monitor or

a keyboard

Many embedded systems must be able to do things in real-time - in a short

amount of time (almost instantly from a human view).

Many embedded systems must be very safe and reliable, especially for medical

devices or avionicscontrolling airplanes.

Starts very quickly. People don't want to wait a minute or two for their car to

1

start or emergency equipment to start.

It uses a special operating system (or sometimes a very small home-made OS)

that helps meet these requirements called a real-time operating system, or

RTOS.

1.3 APPLICATION AREAS

The embedded system market is one of the highest growth areas as there as these

systems are used in very market segment

consumer electronics

office automation

industrial automation

biomedical engineering

wireless communication

data communication

telecommunication

transportation

Military etc.

2

CHAPTER-2

LITERATURE SURVEY

A literature survey is an evaluative report of information found in the literature

related to your selected area of study.  The review should describe, summarize,

evaluate and clarify this literature.  It should give a theoretical base for the research

and help you (the author) determine the nature of your research. Works which are

irrelevant should be discarded and those which are peripheral should be looked at

critically.

A literature review is more than the search for information, and goes beyond

being a descriptiveannotated bibliography. All works included in the review must be

read, evaluated and analyzed (which you would do for an annotated bibliography), but

relationships between the literature must also be identified and articulated, in relation

to your field of research.

2.1 History

It’s generally said that the roots of radio frequency identification technology

can be traced back to World War II. The Germans, Japanese, Americans and British

were all using radarwhich had been discovered in 1935 by Scottish physicist Sir

Robert Alexander Watson-Wattto warn of approaching planes while they were still

miles away. The problem was there was no way to identify which planes belonged to

the enemy and which were a country’s own pilots returning from a mission.

The Germans discovered that if pilots rolled their planes as they returned to

base, it would change the radio signal reflected back. This crude method alerted the

radar crew on the ground that these were German planes and not allied aircraft (this is,

essentially, the first passive RFID system).

Under Watson-Watt, who headed a secret project, the British developed the

first active identify friend or foe (IFF) system. They put a transmitter on each British

plane. When it received signals from radar stations on the ground, it began

broadcasting a signal back that identified the aircraft as friendly. RFID works on this

same basic concept. A signal is sent to a transponder, which wakes up and either

reflects back a signal (passive system) or broadcasts a signal(active system).

3

2.2 SHORT MESSAGE SERVICES

Short Message Service (SMS) is a text messaging service component of

phone, Web, or mobile communication systems. It uses standardized communications

protocols to allow fixe line or mobile phone devices to exchange short text messages.

SMS was the most widely used data application, with an estimated 3.5 billion

active users, or about 80% of all mobile phone subscribers at the end of 2010. The

term "SMS" is used for both the user activity and all types of short text messaging in

many parts of the world. SMS is also employed in direct marketing, known as SMS

marketing.

SMS as used on modern handsets originated from radio telegraphy in radio

memo pagers using standardized phone protocols. These were defined in 1985 as part

of the Global System for Mobile Communications (GSM) series of standards as a

means of sending messages of up to 160 characters to and from GSM mobile

handsets.[ Though most SMS messages are mobile-to-mobile text messages, support

for the service has expanded to include other mobile technologies, such as ANSI

CDMA networks and Digital AMPS, as well as satellite and landlinenetworks.

2.3 PROCESS OF SMS

The Short Message Service is realized by the use of the Mobile Application

Part (MAP) of the SS#7 protocol, with Short Message protocol elements being

transported across the network as fields within the MAP messages. These MAP

messages may be transported using 'traditional' TDM based signaling, or over IP

using SIGTRAN and an appropriate adaptation layer. The Short Message

protocol itself is defined by 3GPP TS 23.040 for the Short Message Service Point to

Point (SMS-PP), and 3GPP TS 23.041 for the Cell Broadcast Service (CBS).

Four MAP procedures are defined for the control of the Short Message Service:

Mobile Originated (MO) short message service transfer.

Mobile Terminated (MT) short message service transfer.

Short message alert procedure.

Short message waiting data set procedure.

4

2.4 Advantages and Disadvantages

Radio Frequency Identification has existed since the 1970s but has only

recently gained popularity for its uses. It was first implemented to help the owners of

livestock keep track of their animal (Bonsor, Keener, &Fenlon, n.d.). Presently, RFID

systems have developed to the point where they have hundreds of uses, ranging from

tracking luggage at an airport to detailing a patient’s medical history in a hospital.

2.4.1 Advantages of RFID Technology

The tag does not need to be in line of sight with the receiver to be read

(compareto a barcode and its optical scanner)  

RFID tags can store a lot of information, and follow instructions

Has the ability to pinpoint location 

Technology is versatile: can be smaller than a thumb tack or can be the size of

a tablet, depending on its use

2.4.2 Disadvantages of RFID Technology

Active RFID can be expensive because of batteries

There still needs to be regulations about RFID guidelines

There is a privacy concern towards RFID devices, for example some claim

that

Wal-Martis infringing on natural rights by overseeing what customers buy

RFID may be easily intercepted, even if it is Encrypted 

It takes a lengthy time to program RFID devices

2.5 Conclusion

The billion dollar industry that RFID has evolved into has done great good for

a lot of different fields. RFID has given doctors the ability for quick access to patients

records, the assurance of accounted merchandise for small business and large alike,

5

and the government the ability to conduct taxes for tolls in this technological day and

age. But with as many benefits as  it has, Radio Frequency Identification's

overwhelming credibility is balanced out by the criticism against it. Though RFID

allows for the allocation and distribution of sensitive information, if that information

is compromised, the effects could be devastating. For there to be order in the realm of

RFID, legislation and guidelines need to be set up and enforced to ensure the integrity

and confidence of the data being communicated, which will in turn help Radio

Frequency Identifications emerge as more secure and advanced.

2.6 Summary

This chapter is about literature review on how we review and reveal the

information based on internet, books, articles, and from news papers. Study has been

made from the researches and the inventor before can start our goal.

6

CHAPTER 3

PROJECT MODULES

The “RFID based Traffic control system by using GSM” is implemented by using various modules given below.

RFID Technology

Micro Controller

Power supply

GSM Modem

LED Indicators

Buzzer

3.1 RFID TECHNOLOGY

RFID technology consists of the necessary three components: Tag, Reader and

the Coordinator. Radio-frequencyidentification (RFID) is the wireless non-contact use

of radio frequency electromagnetic field to transfer data, for the purposes of

automatically identifying and tracking tags attached to objects. The tags contain

electronically stored information. Some tags are powered by and read at short ranges

(a few meters) via magnetic fields (electromagnetic induction), and then act as a

passive transponder to emit microwaves or UHF radiowaves. Others use a local power

source such as a battery, and may operate at hundreds of meters. Unlike a bar code,

the tag does not necessarily need to be within line of sight of the reader, and may be

embedded in the tracked object.

One important feature enabling RFID for tracking objects is its capability to

provide unique identification. One possible approach to item identification is the EPC

(Electronic Product Code), pro-viding a standardized number in the EPCglobal

Network, with an Object Name Service (ONS) pro-viding the adequate Internet

addresses to access or update instance -specific data. However, currently, ONS cannot

be used in a global environment, and since it is a proprietary service, its use is

relatively expensive, especially for participants with limited resources such as SMEs.

As an alter-native, researchers from the Helsinki University have proposed the

notation ID@URI, where ID stands for an identity code, and URI stands for a

7

corresponding Internet address. This allows several partners to use the system and still

guarantee unique identification. The project ‘Identity -Based Tracking and Web-

Services for SMEs’ is currently working on further development of this concept.

3.1.1TYPES OF TAGS AND READERS

RFID tags and readers can be grouped under a number of categories. Their

classification is presented in Table 1

Table 3.1: Types of RFID tags

8

Classification of readers

By design and technology used

Read - only reads data from the tag

- usually a micro-controller-based unit with a wound

output coil,

peak detector hardware, comparators, and firmware

designed to

transmit energy to a tag and read information back from

it by de-

testing the backscatter modulation

- different types for different protocols, frequencies and

standards

Exist

Read/write - reads and writes data from/on the tag

By fixation of the device

Stationary

The device is attached in a fixed way, for example at the

entrance

gate, respectively at the exit gate of products

Mobile In this case the reader is a handy, movable device.

Table 3.2:Classification of RFID tags and

readers

3.1.2RFID systems

RFID systems are closely related to the smart cards described above. Like

smart card systems, data is stored on an electronic data-carrying device the

transponder. However, unlike the smart card, the power supply to the data-carrying

device and the data exchange between the data-carrying device and the reader are

achieved without the use of galvanic contacts, using instead magnetic or

electromagnetic fields. The underlying technical procedure is drawn from the fields of

radio and radar engineering. The abbreviation RFID stands for radio frequency

identification, i.e. information carried by radio waves. Due to the numerous

9

advantages of RFID systems compared with other identification systems, RFID

systems are now beginning to conquer new mass markets.

Description of RFID Systems

In a nutshell, RFID involves detecting and identifying a tagged object through

the data it transmits. This requires a tag (a.k.a. transponder), a reader (a.k.a.

interrogator) and antennae (a.k.a. coupling devices) located at each end of the system.

The reader is typically connected to a host computer or other device that has the

necessary intelligence to further process the tag data and take action. The host

computer is often a part of a larger network of computers in a business enterprise and,

in some cases, is connected to the Internet.

One key element of operation in RFID is data transfer. It occurs with the

connection between a tag and a reader, also known as coupling, through the antennae

on either end.

The coupling in most RFID systems is either electromagnetic (backscatter) or

magnetic (inductive). The method used in a particular implementation depends on the

application requirements, such as the cost, size, speed, and read range and accuracy.

For example, inductively coupled RFID systems typically have a short range,

measured in inches. These types of systems are used mostly in applications, such as

access control, where short range is advantageous. In this case a tag only unlocks an

RFID-enabled door lock when it is moved within close range of the reader, not when

10

people who may be carrying a tag in their wallet or purse are walking past the reader

in a hallway in front of the door.

The element that enables the tag and reader communication is the antenna.

The tag and the reader each have its own antenna.

Another important element in an RFID system is the frequency of operation

between the tag and the reader. Specific frequency selection is driven by application

requirements such as speed, accuracy, and environmental conditions, with standards

and regulations that govern specific applications. For example, RFID applications for

animal tagging have been operating in the 135 kHz frequency band, based on

longstanding regulations and accepted standards.

Although hardware components are responsible for identifying and capturing

data, software components of an RFID application are responsible for managing and

manipulating the data transmitted between the tag and the reader and between the

reader and the host computer.

FIG 3.1 Working of RFID tags

3.1.3Public Transport

Public transportis one of the applications where the greatest potential exists for

the use of RFID systems

3.1.4Benefits of RFID systems

11

The replacement of conventional paper tickets by a modern electronic fare

management system based on contactless smart cards provides a multitude of benefits

to all those involved. Although the purchase costs of a contactless smart card system

are still higher than those of a conventional system, the investment should repay itself

within a short period. The superiority of contactless systems is demonstrated by the

following benefits for users and operators of public transport companies.

3.1.5Benefits for passengers

• Cash is no longer necessary, contactless smart cards can be loaded with large

amounts of money, passengers no longer need to carry the correct change.

• Prepaid contactless smart cards remain valid even if fares are changed.

• The passenger no longer needs to know the precise fare; the system

automatically deducts the correct fare from the card.

• Monthly tickets can begin on any day of the month. The period of validity

begins after the first deduction from the contactless card.

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3.2AT89S52 MICROCONTROLLER

The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer

with 4 Kbytes of Flash Programmable and Erasable Read Only Memory (PEROM).

The device is manufactured using Atmel’s high-density non-volatile memory

technology and is compatible with the industry standard MCS-51Ô instruction set and

pin out. The on-chip Flash allows the program memory to be reprogrammed in-

system or by a conventional non-volatile memory programmer. By combining a

versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C52 is a

powerful microcomputer, which provides a highly flexible and cost effective solution

to many embedded control applications. In 1981, Intel Corporation introduced an 8 bit

microcontroller called 8051. This microcontroller had 128 bytes of RAM, 4K bytes of

chip ROM, two timers, one serial port, and four ports all on a single chip. At the time

it was also referred as “A SYSTEM ON A CHIP”

3.2.1FEATURES OF MICROCONTROLLER

22 Programmable I/O Lines

Three 16-Bit Timer/Counters

Eight Interrupt Sources

4.0V to 5.5V Operating Range

Full Duplex UART Serial Channel

Watchdog Timer

Dual Data Pointer

Power-off Flag

Fast Programming Time

Flexible ISP Programming (Byte and Page Mode)

13

Fig 3.2 Schematic of Microcontroller

14

3.9 PIN CONFIGURATION

Figure 3.3: pin configuration of AT89S52 microcontroller

3.2.2Pin Description

VCC

Supply voltage.

GND

Ground.

15

Port 0

Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin

can sink eight TTL inputs. When 1sare written to port 0 pins,the pins can be used as

high impedance inputs. Port 0 can also be configured to be the multiplexed low order

address/data bus during accesses to external program and data memory. In this mode,

P0 has internal pull ups. Port 0 also receives the code bytes during Flash

programming and outputs the code bytes during program verification.

External pull ups are required during program verification.

Port 1

Port 1 is an 8-bit bidirectional I/O port with internal pull ups.The Port 1 output

buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins, they are

pulled high by the internal pull ups and can be used as inputs. As inputs, Port 1 pins

that are externally being pulled low will source current (IIL) because of the internal

pull ups. In addition, P1.0 and P1.1 can be configured to be the timer/counter 2

external count input (P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX),

respectively, as shown in the following table. Port 1 also receives the low-order

address bytes during Flash programming and verification.

Port 2

Port 2 is an 8-bit bidirectional I/O port with internal pull ups. The Port 2

output buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins,

they are pulled high by the internal pull ups and can be used as inputs. As inputs, Port

16

2 pins that are externally being pulled low will source current (IIL) because of the

internal pull ups. Port 2 emits the high-order address byte during fetches from external

program memory and during accesses to external data memory that use 16-bit

addresses (MOVX @DPTR). In this application, Port 2 uses strong internal pull-ups

when emitting 1s. During accesses to external data memory that use 8-bit addresses

(MOVX @ RI), Port 2emits the contents of the P2 Special Function Register. Port 2

also receives the high-order address bits and some control signals during Flash

programming and verification.

Port 3

Port 2 is an 8-bit bidirectional I/O port with internal pull ups. The Port 2

output buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins,

they are pulled high by the internal pull ups and can be used as inputs. As inputs, Port

2 pins that are externally being pulled low will source current (IIL) because of the pull

ups. Port 2 also serves the functions of various special features of the AT89S52, as

shown in the following table. Port 2 also receives some control signals for Flash

programming and verification.

RST

Reset input. A high on this pin for two machine cycles while the oscillator is

running resets the device. This pin drives High for 96 oscillator periods after the

Watchdog times out. The DISRTO bit in SFR AUXR (address 8EH) can be used to

disable this feature. In the default state of bit DISRTO, the RESET HIGH out feature

is enabled.ALE/PROG Address Latch Enable (ALE) is an output pulse for latching

17

the low byte of the address during accesses to external memory. This pin is also the

program pulse input (PROG) during Flash programming. In normal operation, ALE is

emitted at a constant rate of1/6 the oscillator frequency and may be used for external

timing or clocking purposes. Note, however, that one ALE pulse is skipped during

each access to external data memory. If desired, ALE operation can be disabled by

setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during a

MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the

ALE-disable bit has no effect if the microcontroller is in external execution mode.

PSEN

Program Store Enable (PSEN) is the read strobe to external program memory.

When the AT89S52 is executing code from external program memory, PSEN is

activated twice each machine cycle, except that two PSEN activations are skipped

during each access to external data memory.

EA/VPP

External Access Enable. EA must be strapped to GND in order to enable the

device to fetch code from external program memory locations starting at 0000H up to

FFFFH. Note, however, that if lock bit 1 is programmed, EA will be internally latched

on reset. EA should be strapped to VCC for internal program executions. This pin also

receives the 12-volt programming enable voltage

(VPP) during Flash programming.

XTAL1

Input to the inverting oscillator amplifier and input to the internal clock

operating circuit.

XTAL2

Output from the inverting oscillator amplifier.

18

3.2.3MEMORY ORGANIZATION

The 89C52 micro controller has separate address for program memory and

data memory. The logical separation of program and data memory allows the data

memory to be accessed by 8-bit address, which can be quickly stored and manipulated

by an 8-bit CPU. Nevertheless, 16-bit data memory address can also be generated

through the DPTR register. Program memory (ROM, EPROM) can only be read, not

written to. There can be up to 64k bytes if program memory the lowest 4k bytes of

program are on chip. In the ROM less versions, all program memory is external. The

read strobe for external program is the PSEN (program store enable). Data memory

(RAM) occupies a separate address space from program memory the lowest 128 bytes

of data memory are on chip. Up to 64 bytes of external RAM can be addressed in the

external data memory space. In the ROM less version, the lowest 128bytes of data

memory are on chip. The CPU generates read and write signals, RD and WR, as

needed during external data memory access.

External program memory may be combined if desired by applying the RD

and PSEN signals to the inputs of an AND gate and using the output of the gate as the

read strobe to the external program/data memory.

3.2.4DATA MEMORY

19

3.2.5PROGRAM MEMORY

FIG 3.4 Program Memory

The 128 byte of RAM are divided into 2 segments

a). Register banks 0 – 2 (00 – 1FH)

b). Bit addressable area (20H – 2FH)

c). Scratch pad area (20H – 7FH)

If the SP is initialized to this area enough bytes should be left aside to prevent SP data

destruction.

3.2.6SPECIAL FUNCTION REGISTERS:

A & B REGISTERS:

20

They are used during math and logically operations. The register A is also

used for all data transfers between the micro controller and memory. The B register is

used during multiplication and divided operations. For other instructions it can be

treated as another scratch pad register.

PSW (PROGRAM STATUS WORD):

It contains math flags; user flags F0 and register select bits RS1 and RS0 to

determine the working register bank.

STACK AND STACK POINTER:

Stack is used to hold and retrieve data quickly. The 8 – bit SP is incremented

before data is stored during PUSH and CALL executions. While the stack may reside

any where in on-chip RAM, the SP is initialized to 07H after the stack to begin at

manipulated as a 16 – bit register or as two independent 8 – bit registers.

PC (PROGRAM COUNTER):

It addresses the memory locations that program instructions are to be fetched.

It is the only register that does not have any internal address.

FLAGS:

They are 1–bit register provided to store the results of certain program

instructions. Other instructions can test the conditions of the flags and make the

decisions accordingly. To conveniently address, they are grouped inside the PSW and

PCON.The micro controller has 4 main flags: carry(c), auxiliary carry (AC), over

flow (OV), parity (P) and 2 general-purpose flagsF0, GF0 and GF1.

PORTS:

21

All ports are bi-directional; each consists of a latch, an output driver and an

input buffer. P0, P1, P2 and P2 are the SFR latches ports 0, 1, 2 and 2 respectively.

The main functions of each port are mentioned below.

Port0: input/output bus port, address output port and data input/output port.

Port1: Quasi-bi-directional input/output port.

Port2: Quasi-bi-directional input/output port and address output port.

Port2: Quasi-bi-directional input/output port and control input/output pin.

SBUF (SERIAL BUFFER)

The microcontroller has serial transmission circuit that uses SBUF register to

hold data. It is actually two separate registers, a transmit buffer and a receive buffer

register. When data is moved to SBUF, it goes to transmit buffer, where it is held for

serial transmission and when it is moved from SBUF, it comes from the receive

buffer.

TIMER REGISTER

Register pairs (TH0, TL1), (TH1, TL1) are the 16-bit counter registers for

timer/counters 0 and 1.

CONTROL REGISTERS

SFR’s, IP, TMOD, SCON, and PCON contain control and status bits for the

interrupt system, Timers/counters and the serial port.

OSCILLATOR AND CLOCK CIRCUIT

This circuit generates the clock pulses by which all internal operations are

synchronized. For the microcontroller to yield standard baud rates, the crystal

frequency is chosen as 11.059MHz.

RESET

22

The reset switch is the RST pin of the microcontroller, which is the input to a

Schmitt trigger. It is accomplished by holding the RST pin HIGH for at least two

machine cycles while the oscillator frequency is running the CPU responds by

generating an internal reset.

TIMERS/COUNTERS

A micro controller has two 16- bit Timer/Counter register T0 and T1

configured to operate either as timers or event counters. There are no restrictions on

the duty cycle of the external input signal, but it should be for at least one full

machine to ensure that a given level is sampled at least once before it changes. Timers

0 and 1 have four operating modes: 12-bit mode, 16 – bit mode, 8 – bit auto-reload

mode. Control bits C/t in TMOD SFR select the timer or counter function.

MODE 0

Both timers in MODE0 are counters with a divide – by – 22 pre-scalar. The

timer register is configured as a 12 – bit register with all 8 bits of TH1 and the lower

5-bit of TL1.The upper 2 bits of TL1 are in determinate and should be ignored.

Setting the run flags (TR1) doesn’t clear the register or the registers.

MODE 1

Mode 1 is same as mode 0, except that the timer register is run with all 16

bits. The clock is applied to the combined high and low timer registers. An overflow

occurs on the overflow flag. The timer continues to count.

MODE 2

This mode configures the timer register as an 8 – bit counter (TL1/0) with

automatic reload. Overflow from TL1/0 not only sets TF1/0, but also reloads TL1/0

with the contents of TH1/0, which is preset by software. The reload leaves unchanged.

MODE 3

23

Mode 3 is used for application that requires an extra 8 – bit timer or counter.

Timer 1 in mode 3 simply holds its count. The effect is same as setting TR0. Timer 0

its mode 3 establishes TL0 and TL1 as two separate counters. TL0 uses the timer0

control bits C/T, GATE, TR0, INT0 and TF0. TH0 is locked into a timer function and

over the use of TR1 and TR2 from timer 1. Thus TH0 controls the timer 1 interrupts.

INTERRUPTS

The micro controller provides 6 interrupt sources, 2 external interrupts, 2 timer

interrupts and a serial port interrupt and a reset. The external interrupts (INT0 &

INT1) can each be either level activated or transition activated depending on bits IT0

and IT1 in register TCON. The flags that actually generate these interrupts are IE0 &

IE1 bits in TCON.

TF0 and TF1 generate the timer 0 & 1 interrupts, which are set by a roll over

in their respective timer/counter registers. When a timer interrupt is generated the on-

chip hardware clears the flag that generated it when the service routine is vectored to.

The serial port interrupt is generated by logical OR of R1 & T1. Neither of these flags

is cleared by hardware when service routine is vectored to. In fact, the service routine

itself determines whether R1 & T1 generated the interrupt, and the bit is cleared in the

software.

Upon reset, all interrupts are disabled, meaning that none will be responded to

by the micro controller if they are activated. The interrupts must be enabled by

software in order for the micro controller to respond to them.

SERIAL INTERFACE

The serial port is full duplex, i.e. it can transmit and receive simultaneously. It

is also receive buffered which implies it can begin receiving a second byte before a

previously byte has been read from the receive register. The serial port receives and

transmits register and reading SBUF accesses a physically separate receive register.

This serial interface had four modes of operation:

24

MODE 0:

In this mode of operation the serial data enters and exists through RXD.TXD

outputs the shift clock. Eight data bits are transmitted/ received, with the LSB first,

the baud rate is fixed at 1/12 of the oscillator frequency. Reception is initialized by the

condition RI-0 and REN=1.

MODE 1:

IN this mode 10 bits (a start bit 0, 8 data bits with LSB first and a stop bit are

transmitted through TXD port received through RXD. At the receiving end the stop

bits goes into RB8 in the SFR SCON. The baud rate is variable.

MODE 2:

In the 2, 16 bits (a start bit 0, 8 data bits (LSDB first), a programmable 9th

data bit and a stop bit) are transmitted through TXD or received through RXD. The

baud rate is programmable to either 1/22 or 1/64 of the oscillator frequency

MODE 3:

The function of mode 2 is same as mode 2 except that the baud rate is

variable. Reception is initialized by the incoming start bit if REN=1.

BAUDRATE CALCULATIONS

Baud rate in mode 0 is fixed.

Mode 0 baud rate=oscillator frequency/12

(1 machine cycle=12 clock. cycles)

The baud rate in mode 2 depends on the value of SMOD bit in PCON

Register.

SMOD=0, baud rate= (1/64) x oscillator frequency.

SMOD=1baud rate= (1/22) oscillator frequency.

I.e. mode 2 baud rate= [2(POW) SMOD/64)] x oscillator frequency.

25

In the modes 1 and 2, timer 1 over flow rate and the value of SMOD

determines the baud rate. Baud rate of mode 1 and 2 = [(2(POW) SMOD/22)]

x timer 1 over flow rate.

The timer 1 interrupt should be disabled in this application.

3.2.5 PROGRAM MEMORY LOCK BITS

On the chip are three lock bits, which can be left un-programmed (u) or can be

programmed (p) to obtain the additional features listed in the table below.

When lock bit 1 is programmed, the logic level at the EA pin is sampled and

latched during reset.

Table 3.3: Program memory locks bits

If the device is powered up without a reset, the latch initializes to a random

value, and holds that value until reset is activated. It is necessary that the latched

value of EA be in agreement with the current logic level at that pin in order for the

device to function

26

3.3POWER SUPPLY

Power supply is a reference to a source of electrical power. A device or system

that supplies electrical or other types of energy to an output load or group of loads is

called a power supply unit or PSU. The term is most commonly applied to electrical

energy supplies, less often to mechanical ones, and rarely to others

This power supply section is required to convert AC signal to DC signal and

also to reduce the amplitude of the signal. The available voltage signal from the mains

is 230V/50Hz which is an AC voltage, but the required is DC voltage(no frequency)

with the amplitude of +5V and +12V for various applications.

In this section we have Transformer, Bridge rectifier, are connected serially

and voltage regulators for +5V and +12V (7805 and 7812) via a capacitor (1000µF) in

parallel are connected parallel as shown in the circuit diagram below. Each voltage

regulator output is again is connected to the capacitors of values (100µF, 10µF, 1 µF,

0.1 µF) are connected parallel through which the corresponding output (+5V or

+12V) are taken into consideration.

Fig 3.5 Schematic of power supply

27

3.3.1Transformer

A transformer is a device that transfers electrical energy from one circuit to

another through inductively coupled electrical conductors. A changing current in the

first circuit (the primary) creates a changing magnetic field; in turn, this magnetic

field induces a changing voltage in the second circuit (the secondary). By adding a

load to the secondary circuit, one can make current flow in the transformer, thus

transferring energy from one circuit to the other.

The secondary induced voltage VS, of an ideal transformer, is scaled from the

primary VP by a factor equal to the ratio of the number of turns of wire in their

respective windings:

Basic principle

The transformer is based on two principles: firstly, that an electric current can

produce a magnetic field (electromagnetism) and secondly that a changing magnetic

field within a coil of wire induces a voltage across the ends of the coil

(electromagnetic induction). By changing the current in the primary coil, it changes

the strength of its magnetic field; since the changing magnetic field extends into the

secondary coil, a voltage is induced across the secondary.

A simplified transformer design is shown below. A current passing through

the primary coil creates a magnetic field. The primary and secondary coils are

wrapped around a core of very high magnetic permeability, such as iron; this ensures

that most of the magnetic field lines produced by the primary current are within the

28

iron and pass through the secondary coil as well as the primary coil.FigF

FIG 3.6 Transformer

An ideal step-down transformer showing magnetic flux in the core

Induction law

The voltage induced across the secondary coil may be calculated from

Faraday's law of induction, which states that:

Where VS is the instantaneous voltage, NS is the number of turns in the

secondary coil and Φ equals the magnetic flux through one turn of the coil. If the

turns of the coil are oriented perpendicular to the magnetic field lines, the flux is the

product of the magnetic field strength B and the area A through which it cuts. The

area is constant, being equal to the cross-sectional area of the transformer core,

whereas the magnetic field varies with time according to the excitation of the primary.

Since the same magnetic flux passes through both the primary and secondary coils in

an ideal transformer, the instantaneous voltage across the primary winding equals

29

Taking the ratio of the two equations for VS and VP gives the basic equationfor

stepping up or stepping down the voltage

Ideal power equation

If the secondary coil is attached to a load that allows current to flow, electrical

power is transmitted from the primary circuit to the secondary circuit. Ideally, the

transformer is perfectly efficient; all the incoming energy is transformed from the

primary circuit to the magnetic field and into the secondary circuit. If this condition is

met, the incoming electric power must equal the outgoing power.

Pincoming = IPVP = Poutgoing = ISVS

giving the ideal transformer equation

Pin-coming = IPVP = Pout-going = ISVS

30

giving the ideal transformer equation

If the voltage is increased (stepped up) (VS>VP), then the current is decreased

(stepped down) (IS<IP) by the same factor. Transformers are efficient so this formula

is a reasonable approximation.

If the voltage is increased (stepped up) (VS>VP), then the current is decreased

(stepped down) (IS<IP) by the same factor. Transformers are efficient so this formula

is a reasonable approximation.

The impedance in one circuit is transformed by the square of the turns ratio.

For example, if an impedance ZS is attached across the terminals of the secondary coil,

it appears to the primary circuit to have an impedance of

This relationship is reciprocal, so that the impedance ZP of the primary circuit

appears to the secondary to be

Detailed operation

The simplified description above neglects several practical factors, in

particular the primary current required to establish a magnetic field in the core, and

the contribution to the field due to current in the secondary circuit.

Models of an ideal transformer typically assume a core of negligible

reluctance with two windings of zero resistance. When a voltage is applied to the

31

primary winding, a small current flows, driving flux around the magnetic circuit of

the core. The current required to create the flux is termed the magnetizing current;

since the ideal core has been assumed to have near-zero reluctance, the magnetizing

current is negligible, although still required to create the magnetic field.

The changing magnetic field induces an electromotive force (EMF) across

each winding. Since the ideal windings have no impedance, they have no associated

voltage drop, and so the voltages VP and VS measured at the terminals of the

transformer, are equal to the corresponding EMFs. The primary EMF, acting as it

does in opposition to the primary voltage, is sometimes termed the "back EMF". This

is due to Lenz's law which states that the induction of EMF would always be such that

it will oppose development of any such change in magnetic field.

3.3.2Bridge Rectifier

A diode bridge or bridge rectifier is an arrangement of four diodes in a bridge

configuration that provides the same polarity of output voltage for any polarity of

input voltage. When used in its most common application, for conversion of

alternating current (AC) input into direct current (DC) output, it is known as a bridge

rectifier. A bridge rectifier provides full-wave rectification from a two-wire AC input,

resulting in lower cost and weight as compared to a center-tapped transformer design,

but has two diode drops rather than one, thus exhibiting reduced efficiency over a

center-tapped design for the same output voltage.

Basic Operation

When the input connected at the left corner of the diamond is positive with

respect to the one connected at the right hand corner, current flows to the right along

the upper colored path to the output, and returns to the input supply via the lower one.

32

When the right hand corner is positive relative to the left hand corner, current

flows along the upper colored path and returns to the supply via the lower colored

path.

In each case, the upper right output remains positive with respect to the lower

right one. Since this is true whether the input is AC or DC, this circuit not only

produces DC power when supplied with AC power: it also can provide what is

sometimes called "reverse polarity protection". That is, it permits normal functioning

when batteries are installed backwards or DC input-power supply wiring "has its

wires crossed" (and protects the circuitry it powers against damage that might occur

without this circuit in place).

Prior to availability of integrated electronics, such a bridge rectifier was

always constructed from discrete components. Since about 1950, a single four-

terminal component containing the four diodes connected in the bridge configuration

became a standard commercial component and is now available with various voltage

and current ratings.

33

Output smoothing (Using Capacitor)

For many applications, especially with single phase AC where the full-wave

bridge serves to convert an AC input into a DC output, the addition of a capacitor may

be important because the bridge alone supplies an output voltage of fixed polarity but

pulsating magnitude (see diagram above).

The function of this capacitor, known as a reservoir capacitor (aka smoothing

capacitor) is to lessen the variation in (or 'smooth') the rectified AC output voltage

waveform from the bridge. One explanation of 'smoothing' is that the capacitor

provides a low impedance path to the AC component of the output, reducing the AC

voltage across, and AC current through, the resistive load. In less technical terms, any

drop in the output voltage and current of the bridge tends to be cancelled by loss of

charge in the capacitor.

34

This charge flows out as additional current through the load. Thus the change

of load current and voltage is reduced relative to what would occur without the

capacitor. Increases of voltage correspondingly store excess charge in the capacitor,

thus moderating the change in output voltage / current. Also see rectifier output

smoothing.

The simplified circuit shown has a well deserved reputation for being

dangerous, because, in some applications, the capacitor can retain a lethal charge after

the AC power source is removed. If supplying a dangerous voltage, a practical circuit

should include a reliable way to safely discharge the capacitor. If the normal load can

not be guaranteed to perform this function, perhaps because it can be disconnected,

the circuit should include a bleeder resistor connected as close as practical across the

capacitor. This resistor should consume a current large enough to discharge the

capacitor in a reasonable time, but small enough to avoid unnecessary power waste.

Because a bleeder sets a minimum current drain, the regulation of the circuit,

defined as percentage voltage change from minimum to maximum load, is improved.

However in many cases the improvement is of insignificant magnitude.

The capacitor and the load resistance have a typical time constant τ = RC

where C and R are the capacitance and load resistance respectively. As long as the

load resistor is large enough so that this time constant is much longer than the time of

one ripple cycle, the above configuration will produce a smoothed DC voltage across

the load.

In some designs, a series resistor at the load side of the capacitor is added. The

smoothing can then be improved by adding additional stages of capacitor–resistor

pairs, often done only for sub-supplies to critical high-gain circuits that tend to be

sensitive to supply voltage noise.

The idealized waveforms shown above are seen for both voltage and current

when the load on the bridge is resistive. When the load includes a smoothing

capacitor, both the voltage and the current waveforms will be greatly changed. While

the voltage is smoothed, as described above, current will flow through the bridge only

during the time when the input voltage is greater than the capacitor voltage. For

35

example, if the load draws an average current of n Amps, and the diodes conduct for

10% of the time, the average diode current during conduction must be 10n Amps.

This non-sinusoidal current leads to harmonic distortion and a poor power factor in

the AC supply.

In a practical circuit, when a capacitor is directly connected to the output of a

bridge, the bridge diodes must be sized to withstand the current surge that occurs

when the power is turned on at the peak of the AC voltage and the capacitor is fully

discharged. Sometimes a small series resistor is included before the capacitor to limit

this current, though in most applications the power supply transformer's resistance is

already sufficient.

Output can also be smoothed using a choke and second capacitor. The choke

tends to keep the current (rather than the voltage) more constant. Due to the relatively

high cost of an effective choke compared to a resistor and capacitor this is not

employed in modern equipment.

Some early console radios created the speaker's constant field with the current

from the high voltage ("B +") power supply, which was then routed to the consuming

circuits, (permanent magnets were considered too weak for good performance) to

create the speaker's constant magnetic field. The speaker field coil thus performed 2

jobs in one: it acted as a choke, filtering the power supply, and it produced the

magnetic field to operate the speaker.

3.3.3 Voltage Regulator

A voltage regulator is an electrical regulator designed to automatically

maintain a constant voltage level.

The 78xx (also sometimes known as LM78xx) series of devices is a family of

self-contained fixed linear voltage regulator integrated circuits. The 78xx family is a

very popular choice for many electronic circuits which require a regulated power

supply, due to their ease of use and relative cheapness. When specifying individual

ICs within this family, the xx is replaced with a two-digit number, which indicates the

output voltage the particular device is designed to provide (for example, the 7805 has

36

a 5 volt output, while the 7812 produces 12 volts). The 78xx line is positive voltage

regulators, meaning that they are designed to produce a voltage that is positive

relative to a common ground. There is a related line of 79xx devices which are

complementary negative voltage regulators. 78xx and 79xx ICs can be used in

combination to provide both positive and negative supply voltages in the same circuit,

if necessary.

78xx ICs have three terminals and are most commonly found in the TO220

form factor, although smaller surface-mount and larger TrO3 packages are also

available from some manufacturers. These devices typically support an input voltage

which can be anywhere from a couple of volts over the intended output voltage, up to

a maximum of 35 or 40 volts, and can typically provide up to around 1 or 1.5 amps of

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

37

3.4GSM TECHNOLOGY

GSM is a global system for mobile communication GSM is an international

digital cellular telecommunication. The GSM standard was released by ETSI

(EuropeanStandard Telecommunication Standard) back in 1989. The first commercial

services werelaunched in 1991 and after its early introduction in Europe; the standard

went global in1992. Since then, GSM has become the most widely adopted and

fastest-growing digitalcellular standard, and it is positioned to become the world’s

dominant cellular standard.

Today’s second-generation GSM networks deliver high quality and secure

mobile voice and data services (such as SMS/ Text Messaging) with full roaming

capabilities across the world. GSM platform is a hugely successful technology and as

unprecedented story of global achievement. In less than ten years since the first GSM

network was commercially launched, it become, the world’s leading and fastest

growing mobile standard, spanning over 173 countries. Today, GSM technology is in

use by more than one in ten of the world’s population and growth continues to sour

with the number of subscriber worldwide expected to surpass one billion by through

end of 2003Today’s GSM platform is living, growing and evolving and already offers

an expanded and feature-rich ‘family’ of voice and enabling services.

The Global System for Mobile Communication (GSM) network is a cellular

telecommunication network with a versatile architecture complying with the ETSI

GSM 900/GSM 1800 standard. Siemen’s implementation is the digital cellular mobile

communication system D900/1800/1900 that uses the very latest technology to meet

every requirement of the standard.

38

S.N. Parameter Specifications

1 Reverse Channel frequency 890-915MHz

2 Forward Channel frequency 935-960 MHz

3 Tx/Rx Frequency Spacing 45 MHz

4 Tx/Rx Time Slot Spacing 3 Time slots

5 Modulation Data Rate 270.833333kbps

6 Frame Period 4.615ms

7 Users per Frame 8

8 Time Slot Period 576.9microsec

9 Bit Period 3.692 microsecond

10 Modulation 0.3 GMSK

11 ARFCN Number 0 to 124 & 975 to 1023

12 ARFCN Channel Spacing 200 kHz

13 Interleaving 40 ms

14 Voice Coder Bit Rate 13.4kbps

Table 3.4 GSM specification

39

GSM services follow ISDN guidelines and classified as either teleservices or data

services. Tele services may be divided into three major categories:

• Telephone services, include emergency calling and facsimile. GSM also

supports Videotex and Teletex, through they are not integral parts of the

GSM standard.

• Bearer services or Data services, which are limited to layers 1, 2 and 3 of

the OSI reference model. Data may be transmitted using either a

transparent mode or nontransparent mode.

• Supplementary ISDN services, are digital in nature, and include call

diversion, closed user group, and caller identification. Supplementary

services also include the short message service (SMS).

3.4.1 SHORT MESSAGE SERVICE

SMS stands for Short Message Service. It is a technology that enables the

sending and receiving of message between mobile phones. SMS first appeared in

Europe in 1992. It was included in the GSM (Global System for Mobile

Communication) standards right at the beginning. Later it was ported to wireless

technologies like CDMA and TDMA. The GSM and SMS standards were originally

developed by ETSI. ETSI is the abbreviation for European Telecommunication

Standard Institute. Now the 3GPP (Third Generation Partnership Project) is

responsible for the development and maintenance of the GSM and SMS standards.

One SMS message can contain at most 140 bytes (1120 bits) of data, so one

SMS message can contain up to:

• 160 characters if 7-bit character encoding is used. (7-bit character encoding is

suitable for encoding Latin characters like English alphabets.)

• 70 characters if 16-bit Unicode UCS2 character encoding is used. (SMS text

40

messages containing non-Latin characters like Chinese character should use

16-bit character encoding.)

Once the message is sent the message is received by SMSC, which must then

get it to the appropriate mobile device. To do this the SMSC sends a SMS request to

Home Location Register (HLR) to find the roaming customer. Once HLR receives the

request, it responds to the SMSC with the subscriber’s status:

1 Inactive or active

2 Where subscriber is roaming.

If the response is “inactive“, then the SMSC will hold onto the message for a

period of time. When the subscriber access his device, the HLR sends a SMS

notification to the SMSC and the SMSC will attempt delivery.

The SMSC transfer the message in a Short Message Delivery Point to Point

format to the serving system. The system pages the device, and if it responds, the

message gets delivered. The SMSC receives verification that the message was

received by the end user, then categorizes the message as “sent” and will not attempt

to send again.

SMS provides a mechanism for transmitting short message to and from

wireless devices. The service makes use of an SMSC, which acts as a store and

forward system for short messages.

One major advantage of SMS is that it is supported by 100% GSM mobile

phones. Almost all subscription plans provided by wireless carriers include

inexpensive SMS messaging service.

3.4.2 Short Message Service Center (SMSC)

SMSC is a combination of hardware and software responsible for the relaying

and storing and forwarding of short message between an SME and mobile device.

41

The SMSC must have high reliability, subscriber capacity, and message

throughput. In addition, the system should be easily scalable to accommodate growing

demand for SMS in the network.

Normally, an IN-based solution will allow for a lower entry cost compared to

point solutions because it can support other applications on single hardware platform

and share resources, thereby spreading the deployment cost over several services and

applications.

Another factor to be considered is the ease of operation and maintenance of

the application, as well as the flexibility to activate new services and upgrade to new

software releases.

Nepal has two mobile companies

• Nepal telecommunication

• Spice Nepal Pvt.Ltd.

3.4.3 Short Message Peer to Peer Protocol

The short message peer to peer protocol (SMPP) is a protocol for exchanging

SMS messages between SMS peer entities such as message service centers. It is often

used to allow third parties (e.g. content suppliers like news organizations) to submit

messages, often in bulk.

42

3.5LIGHT EMITTING DIODE

A light-emitting diode (LED) is a two-lead semiconductor light source that

resembles a basic PN-junction diode, except that an LED also emits light.When an LED's

anode lead has a voltage that is more positive than its cathode lead by at least the LED's

forward voltage drop, currentflows. Electrons are able to recombine with holes within the

device, releasing energy in the form of photons. This effect is called electroluminescence,

and the color of the light (corresponding to the energy of the photon) is determined by the

energy band gap of the semiconductor.

An LED is often small in area (less than 1 mm2), and integrated optical

components may be used to shape its radiation pattern.

Appearing as practical electronic components in 1962, the earliest LEDs emitted

lowintensity infrared light. Infrared LEDs are still frequently used as transmitting

elements in remote-control circuits, such as those in remote controls for a wide variety of

consumer electronics. The first visible-light LEDs were also of low intensity, and limited

to red. Modern LEDs are available across the visible,ultraviolet, and infraredwavelengths,

with very high brightness.

Early LEDs were often used as indicator lamps for electronic devices, replacing

small incandescent bulbs. They were soon packaged into numeric readouts in the form

of seven-segment displays, and were commonly seen in digital clocks.

Recent developments in LEDs permit them to be used in environmental and task

lighting. LEDs have many advantages over incandescent light sources including lower

energy consumption, longer lifetime, improved physical robustness, smaller size, and

faster switching. Light-emitting diodes are now used in applications as diverse as aviation

lighting, automotive headlamps, advertising,general lighting, traffic signals, and camera

flashes. However, LEDs powerful enough for room lighting are still relatively expensive,

and require more precise current and heat management than compact fluorescent

lamp sources of comparable output.

43

LEDs have allowed new text, video displays, and sensors to be developed, while

their high switching rates are also useful in advanced communications technology.

Fig 3.7 LED

44

3.6BUZZER

A buzzer or beeper is an audio signaling device, which may mechanical, electro-

mechanical, or piezoelectric. Typical uses of buzzers and beepers include alarm

devices, timers and confirmation of user input such as a mouse click or keystroke.

FIG 3.9 Buzzer

45

CHAPTER-4

IMPLEMENTATION OF PROJECT

4.1 INTRODUCTION

The project is implemented using RFID technology and 8051 Micro controller.

This paper suggests building a RFID system using 8051 Micro controller that can identify

a particular vehicle in traffic as well as identify traffic density and act accordingly to

control the traffic. Automatic detection of vehicle can be used to provide useful estimates

of the density of traffic from one place to another leading to proper and controlled flow of

traffic. In case of metropolitan cities of India the traffic sometimes goes out of control

leading to jams thus people have to face inconvenience while travelling. Radio Frequency

Identification (RFID) tags has been proposed to be used in this project. Each vehicle

would be attached with a RFID card with them. As soon as they enter into the range of

reader the tag would automatically get read and the traffic light would act accordingly for

proper traffic flow and in case of instructing a vehicle individually an audio device would

be attached to it. The data will be stored and processed in the processor attached to the

RFID reader. Even the government is planning to tag every vehicle which gets into the

road for security purposes your cars will be tagged.

4.1.1 SIGNIFICANCE

The ministry of heavy industries is considering a proposal to make it mandatory

to fit RFID-enabled devices in the cars manufactured in India. It is believed that RFID

tags would help in traffic management as traffic violations by motorists could be tracked

and all violations identified. Also, motorists would get charged automatically as soon as

they enter a toll area. The ministry of urban development has already discussed a similar

agenda with many states. The ministry has proposed a „core area charge‟ for different

cities to reduce traffic congestion in the city’s nerve center. So, people could end up

paying a special levy to drive into Connaught Circus, the heart of the Capital. 8051 Micro

controller is used in this field because it’s one of the powerful controllers which are

mending for such embedded works. Road fatalities are a major concern in the developed

46

world. Recent studies show that a third of the number of fatal or serious accidents are

associated with excessive or inappropriate speed, as well as changes in the roadway (like

the presence of road-work or unexpected obstacles). So this system even can catch hold

such vehicles which drive at in appropriate speed.

4.1.2 Objectives

To develop the short message services (SMS) systems received by the control

room and contain information about the vehicle information.

To develop the vehicle monitoring system database for vehicle detection

connected with RFID tags.

4.2 HARDWARE COMPONENTS

RFID Technology

Microcontroller

Power Supply

GSM Modem

LED Indicators

Buzzer

4.3 SOFTWARE COMPONENTS

KEIL Software For C Programming

Express PCB For Layout Design

Express SCH For Schematic Design

47

4.4 BLOCK DIAGRAM

To integrate and testing the SMS system and vehicle monitoring system

48

4.5 SCHEMATIC DIAGRAM

Fig 4.1 Schematic Diagram

49

4.6 ADVANTAGES

1.The system is easy to understand.

2. Avoids the collision of vehicle by controlling the speed.

3.Easy to set up the system.

4. No direct Line of Sight required for identification & tracking.

5. Enables very specific detection of vehicles.

6. Simultaneous multiple detection of vehicles are possible using RFID.

7. No performance degradation during harsh weather.

4.7 APPLICATIONS

Normally, this type of system is useful in case of emergency areas where traffic is

main concern & little carelessness may cause accident & death may occur. Specially, this

is useful in following applications.

1.At school gates

2. In hospital premises.

3. IN MALLS

4.Tollgates and RFID

5.Cellular Towers

6. Image Processing

7.Satellite and GPS

8.Cartel

9.MGate

50

CHAPTER 5

RESULT

The basic operation of this project to protect the traffic rules from the humans

whose violating the traffic rules. The process implementing this project some components

are used in this project such as 8051 microcontroller, RFID system, LED indicators,

buzzer, etc.

All the components are connected to the 8051 microcontroller based on the pin

configuration as shown in schematic diagram. The working of each and every

components are internally depends on another component or module.

Fig 5.1 Project Kit

5.1 OPERATION

The project kit mainly operating on the microcontroller. All the modules and

components are connected to the bread board. Each and every component and modules

51

have their own work but they internally connected to the microcontroller and follow the

instructions of 8015. In this project configuration power supply gives the dc power to the

kit. All the modules are working on the based programmer coding.

5.2 WORKING

Fig 5.2 Working of RFID

This kit is generally used in the traffic signals, it operates based on the working of traffic

signal lights. Whenever the red light indication is on then the RFID reader starts working

and it release the magnetic field , at that time whenever any vehicle cross the indicated

line RFID reader reads the vehicle information through the RFID tags which are

connected to the vehicle. Immediately the RFID reader reads that and send the

information of the vehicle to the nearest control room or next junction by using GSM

modem. Then the authorized persons able to caught the vehicle.

By using this process we can able to control the traffic violation and reduce the

number of traffic polices for controlling the traffic, we can use them for another

important work. This is not only for using vehicle detecting but also we can use for some

more applications like speed control of vehicles, student attendance management,

offices ,toll taxes, etc.

52

CONCLUSION

The designed system gives the complete solution over the problem of traffic

specially in case of school areas where parents vehicle or privatevehicles are coming for

dropping or picking up their children or students with the help of designed system speed

of vehicle is kept in tolerable range by the indication of the signal so that traffic is neatly

drived and ultimately vehicle collision is avoided which is leading to zero chances of

accidents. The designed system is also intended for sending a message through a

dedicated mobile to the student’s parents by keeping record of their entrance or leaving

time of school which makes parents tension free those who are not able to dropped or

picked up from school. This system is also useful for especially in case of dummy

students because the special RFID tag is provided to each student so without verifying the

RFID tag students are not able to enter in the school campus.

In short this system is very useful for controlling the speed of vehicle &

ultimately avoidance of collision with in-out information of the student to their parents.

FUTURE SCOPE

Though, the system is well designed still it has limitation of distance or area

coverage. This problem can be solved using the module of zigbee. For wireless

transmission zigbee is the best solution that can replace existing RF trans receiver. In

addition to this, signal indication i.e. RED& YELLOW signals may be replace wirelessly

instead of wired.

53

BIBLIOGRAPHY

1. http://en.wikipedia.org/wiki/Radio-frequency_identification

2. http://www.keil.com/books/8051books.asp

3. en.wikipedia.org/wiki/GSM

4. en.wikipedia.org/wiki/Light-emitting_diode

5. www.technopundits.in/final-year-projects/

6. Krause, B., von Altrock, C., Pozybill, M.: Intelligent Highway by Fuzzy Logic:

Congestion Detection and Traffic Control on Multi-Lane Roads With Variable Road

Signs. Proceedings of EUFIT`96, Aachen, Germany, 1996

7. Cherrett, T., Waterson, B. And mcdonald, M. (2005) Remote automatic Incident

detection using inductive loops. Proceedings of the Institution of Civil Engineers:

Transport, 158, (3), 149-155.

8.Palubinskas, G., Kurz, F., and Reinartz, P., 2009. Traffic congestion Parameter

estimation in time series of airborne optical remote Sensing images. In: Proc. Of

ISPRS Hannover Workshop 2009 - High Resolution Earth Imaging forgeospatial

Information, 2-5 June, 2009, Hannover, Germany, ISPRS.

9. Palubinskas, Gintautas and Kurz, Franz and Reinartz, Peter (2008) Detection of

trafficcongestion in optical remote sensing imagery. In: International Geoscience

and Remote Sensing Symposium. IEEE. IGARSS08, 2008-07-06 - 2008-07-11,

Boston,USA.

10.P. Pongpaibool, P. Tangamchit and K. Noodwong, "Evaluation of RoadTraffic

Congestion Using Fuzzy Techniques," Proceeding of IEEE TENCON 2007, Taipei,

Taiwan, October 2007.

11. Agilent Intelligent Traffic Video Detection Workstation Data Sheet.

Http://cp.literature. Agilent.com/litweb/pdf/5990-4034EN.pdf

54

55

APPENDIX

PROGRAMMING MICROCONTROLLER

A compiler for a high level language helps to reduce production time. To program

the AT89S52 microcontroller the Keilµv3 is used. The programming is done strictly in

the embedded C language. Keilµv3 is a suite of executable, open source software

development tools for the microcontrollers hosted on the Windows platform.

The compilation of the C program converts it into machine language file (.hex).

This is the only language the microcontroller will understand, because it contains the

original program code converted into a hexadecimal format. During this step there are

some warnings about eventual errors in the program. This is shown in Fig 5.1. If there

are no errors and warnings then run the program, the system performs all the required

tasks and behaves as expected the software developed. If not, the whole procedure will

have to be repeated again. Fig 5.2 shows expected outputs for given inputs when run

compiled program.

One of the difficulties of programming microcontrollers is the limited amount of

resources the programmer has to deal with. In personal computers resources such as

RAM and processing speed are basically limitless when compared to microcontrollers. In

contrast, the code on microcontrollers should be as low on resources as possible.

Keil Compiler:

Keil compiler is software used where the machine language code is written and

compiled. After compilation, the machine source code is converted into hex code which

is to be dumped into the microcontroller for further processing. Keil compiler also

supports C language code.

56

Fig 1: Compilation of source Code

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Fig 2: Run the compiled program

Proload:

Proload is software which accepts only hex files. Once the machine code is

converted into hex code, that hex code has to be dumped into the microcontroller and this

is done by the Proload. Proload is a programmer which itself contains a microcontroller

in it other than the one which is to be programmed. This microcontroller has a program in

it written in such a way that it accepts the hex file from the Keil compiler and dumps this

hex file into the microcontroller which is to be programmed. As the Proload programmer

kit requires power supply to be operated, this power supply is given from the power

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supply circuit designed above. It should be noted that this programmer kit contains a

power supply section in the board itself but in order to switch on that power supply, a

source is required. Thus this is accomplished from the power supply board with an output

of 12volts.

Fig 3: Atmel AT89C2051 Device programmer

Features

Supports major Atmel 89 series devices

Auto Identify connected hardware and devices

Error checking and verification in-built

Lock of programs in chip supported to prevent program copying

20 and 40 pin ZIF socket on-board

Auto Erase before writing and Auto Verify after writing

Informative status bar and access to latest programmed file

Simple and Easy to use

Works on 57600 speed

Description

It is simple to use and low cost, yet powerful flash microcontroller programmer

for the Atmel 89 series. It will Program, Read and Verify Code Data, Write Lock Bits,

Erase and Blank Check. All fuse and lock bits are programmable. This programmer has

intelligent onboard firmware and connects to the serial port. It can be used with any type

of computer and requires no special hardware. All that is needed is a serial

communication ports which all computers have.

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All devices have signature bytes that the programmer reads to automatically

identify the chip. No need to select the device type, just plug it in and go! All devices also

have a number of lock bits to provide various levels of software and programming

protection. These lock bits are fully programmable using this programmer. Lock bits are

useful to protect the program to be read back from microcontroller only allowing erase to

reprogram the microcontroller. The programmer connects to a host computer using a

standard RS232 serial port. All the programming 'intelligence' is built into the

programmer so you do not need any special hardware to run it. Programmer comes with

window based software for easy programming of the devices.

Programming Software

Computer side software called 'Proload V4.1' is executed that accepts the Intel

HEX format file generated from compiler to be sent to target microcontroller. It auto

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detects the hardware connected to the serial port. It also auto detects the chip inserted

and bytes used. Software is developed in Delphi 7 and requires no overhead of any

external DLL.

Fig 4: Writing the programs bytes onto the microcontroller

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