37706524 Vehicle Ignition System for Safety

8/4/2019 37706524 Vehicle Ignition System for Safety

1/12

SMS CONTROLLED

VEHICLE IGNITIONSYSTEM FOR SAFTY

A vehicle ignition system comprises a keycylinder and a key arranged such that thevehicle can be put in a state in which the key


2/12

is removed from the cylinder leaving theengine running. The system includes a firstsafety check system which prevents operation

to say state unless one or more of a first setof safeguard conditions is met. A timer isarranged to be automatically started tomeasure a predetermined time delay fromremoval of the key when the engine isrunning, and a second safety check systemoperates when the vehicle is in said state toshut down the engine automatically if one of asecond set of safeguard conditions occurs, thesecond set of safeguard conditions includingthat the time delay has expired.

INTRODUCTION-:The project is aimed at developing and testingthe use of mobile phones to remotely controlan appliance control system. Themicrocontroller would then control an device

based on the information given to it. Theproposed solution will need to be easy to use,simple, secure, robust and be useful on mostmobile phones. To achieve this testing will


3/12

need to be carried out to create a usefulsystem.

The report consists of a background into thearea of 8051 microcontroller and mobilecommunication, how they are interfaced toeach other and AT (Attention) commands setused in communication.

HARDWARE USED

1. AT command supporting GSM mobilephone.

2. 89S52 Microcontroller3. Max 232 IC.4. Relays5. Relay driver IC ULN 28036. Voltage regulator 7805.7. Diode IN40078. GSM Phone

SOFTWARE USED1. Keil u-Vision 3.0


4/12

Keil Software is used provide you with

software development tools for 8051 based

microcontrollers. With the Keil tools, you can

generate embedded applications for virtually

every 8051 derivative. The supported

microcontrollers are listed in the -vision

2PRO51 Programmer Software

THEORY OF OPERATION

In this project we interfaced 8051microcontroller with Motorolas C168 GSM

mobile phone to decode the receivedmessage and do the required action. Theprotocol used for the communication betweenthe two is AT command.

The microcontroller pulls the SMS received byphone, decode it, recognizes the

Mobile no. and then switches on the relaysattached to its port to control the appliances.After successful operation, controller sendsback the acknowledgement to the usersmobile through SMS.


5/12

AT-Command set

The following section describes the AT-Command set. The commands can be triedout by connecting a GSM modem to one ofthe PCs COM ports. Type in the test-command, adding CR + LF (Carriage return +Line feed = \r\n) before executing. Table givesan overview of the implemented AT-Commands in this application. The use of thecommands is described in the later sections.

AT-Command set overview

Command Description

AT

Check if serialinterface and GSMmodem is working.

ATE0 Turn echo off, lesstraffic on serial line.

AT+CNMI Display of newincoming SMS.

AT+CPMSSelection of SMSmemory.

AT+CMGF SMS string format,


6/12

how they arecompressed.

AT+CMGR

Read new message

from a given memorylocation.

AT+CMGSSend message to agiven recipient.

AT+CMGD Delete message.

A BRIEF INTRODUCTION TO 8051MICROCONTROLLER:

When we have to learn about a newcomputer we have to familiarize about themachine capability we are using, and we can

do it by studying the internal hardware design(devices architecture), and also to know aboutthe size, number and the size of the registers.

A microcontroller is a single chip thatcontains the processor (the CPU), non-volatilememory for the program (ROM or flash),volatile memory for input and output (RAM), aclock and an I/O control unit. Also called a"computer on a chip," billions of microcontroller units (MCUs) are embedded


7/12

each year in a myriad of products from toys toappliances to automobiles. For example, asingle vehicle can use 70 or more

microcontrollers. The following picturedescribes a general block diagram ofmicrocontroller.

89s52: The AT89S52 is a low-power, high-

performance CMOS 8-bit microcontroller with8K bytes of in-system programmable Flashmemory. The device is manufactured usingAtmels high-density nonvolatile memorytechnology and is compatible with theindustry-standard 80C51 instruction set andpinout. The on-chip Flash allows the program

memory to be reprogrammed in-system or bya conventional nonvolatile memory pro-grammer. By combining a versatile 8-bit CPUwith in-system programmable Flash on amonolithic chip, the Atmel AT89S52 is apowerful microcontroller, which provides a

highly flexible and cost-effective solution tomany, embedded control applications. TheAT89S52 provides the following standardfeatures: 8K bytes of Flash, 256 bytes of RAM,32 I/O lines, Watchdog timer, two data


8/12

pointers, three 16-bit timer/counters, a six-vector two-level interrupt architecture, a fullduplex serial port, on-chip oscillator, and clock

circuitry. In addition, the AT89S52 is designedwith static logic for operation down to zerofrequency and supports two softwareselectable power saving modes. The IdleMode stops the CPU while allowing the RAM,timer/counters, serial port, and interruptsystem to continue functioning. The Power-down mode saves the RAM con-tents butfreezes the oscillator, disabling all other chipfunctions until the next interrupt


9/12

The hardware is driven by a set of programinstructions, or software. Once familiar withhardware and software, the user can then


10/12

apply the microcontroller to the problemseasily.

The pin diagram of the 8051 shows all ofthe input/output pins unique tomicrocontrollers:

The following are some of the capabilities of

8051 microcontroller.

Internal ROM and RAM

I/O ports with programmable pins

Timers and counters


11/12

Serial data communication

The 8051 architecture consists of these

specific features:

16 bit PC &data pointer (DPTR)

8 bit program status word (PSW)

8 bit stack pointer (SP)

Internal ROM 4k

Internal RAM of 128 bytes.

4 register banks, each containing8 registers

80 bits of general purpose datamemory

32 input/output pins arranged asfour 8 bit ports: P0-P3

Two 16 bit timer/counters: T0-T1 Two external and three internal

interrupt sources Oscillator andclock circuits.

BLOCK DIAGRAM OFPROJECT


12/12

Documents

37706524 Vehicle Ignition System for Safety