Monitoring and Monitoring and ControllingControllingof Devices of Devices Using GSMUsing GSM

By:By:

PriyankaPriyanka

(ECE)(ECE)

CONTENTSCONTENTS• Objective• Introduction• Block Diagram• Working Principle• Advantages• Applications• Limitations• Future Scope of Work• Conclusion

OBJECTIVEOBJECTIVE

The objective of this project is to design and develop a wireless communication link to monitor and control equipments that are far away from the user and also develop a high security system to keep a check on them..

INTRODUCTIONINTRODUCTION• The proposed system is based on ATMEL

89S52 microcontroller.• The transmitter is a mobile phone which

uses certain codes corresponding to a particular relay to which the device is connected.

• At the receiver, the GSM modem receives the message from the mobile phone and gives it to the microcontroller which acts to control the devices.

BLOCK DIAGRAMBLOCK DIAGRAM RF TRANSMITTER RF RECEIVER

GSM TRANSMITTER

GSM RECEIVER

RF Receiver

MICROCONTROLLER

(at 89s52)

RF decoder

gsm modem max 232

Table Fan (Device 1) relay 1

Table Lamp (Device 2) relay 2

LCD Display

Buzzer

memory at24c04

Power supply(lm 7805)

Sensor

RF Encoder RF Transmitter

WORKING PRINCIPLEWORKING PRINCIPLE• At the transmitter side, the user

sends an SMS to the GSM modem using AT commands indicating which device is to be controlled.

• At the receiver side, Microcontroller controls the devices through relays depending on the code received by the GSM modem.

POWER SUPPLYPOWER SUPPLY The microcontroller and other

devices get power supply from AC to Dc adapter through 7805, 5 volts regulator. The adapter output voltage will be 12V DC non regulated.

AC/DC ADOPTORREGULATOR

7805FILTERS

AC POWER DC OUTPUT

GSM MODEMGSM MODEM• GSM Modem is a multi-

functional, ready to use, rugged unit that can be embedded or plugged into any application.

• The Modem can be controlled and customized to various levels by using the standard AT commands.

GSM MODEM(CONT…)GSM MODEM(CONT…)The modem comprises several

interfaces:-• LED Function including operating

Status• External antenna • Serial and control link • Power Supply • SIM card holder

COMMANDS FOR SMS COMMANDS FOR SMS OPERATIONSOPERATIONS

Device ON • (PASSWORD) SYSTEM1 ON#Device OFF• (PASSWORD) SYSTEM1 OFF#Device ON • (PASSWORD) SYSTEM2 ON#Device OFF• (PASSWORD) SYSTEM2 OFF#CHECH THE STATUS• (PASSWORD) STATUS#

MICROCONTROLLER-MICROCONTROLLER-AT89S52AT89S52

• The AT89S52 is a low-power, high-performance CMOS 8-bit micro controller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s nonvolatile memory technology .

• It is a powerful microcontroller which provides a highly-flexible, cost effective solution to many embedded control applications.

• The code written is downloaded into the microcontroller chip using an universal programmer.

MAX232MAX232• MAX232 was created for one

purpose, to interface between Data Terminal Equipment (DTE) and Data Communications Equipment (DCE) employing serial binary data interchange.

• So as stated the DTE is the terminal or computer and the DCE is the modem or other communications device.

EEPROM EEPROM

• electrically erasable and programmable read only memory (EEPROM) is organized as words of 8 bits each.

Features:• 2-Wire Serial Interface (I2C protocol)• High Reliability Vital role of External EEPROM memory : To store the status of the relay

switches.

I2CI2C

• The START condition acts as a signal to all connected IC's that something is about to be transmitted on the bus.

• A STOP condition is sent. This is the signal for all devices on the bus that the bus is available again (idle).

RELAYRELAY• Relays use an electromagnetic coil to move the

poles of a switch when powered. There are three pairs of connections known as common, normally open and normally closed.

• The center terminal block is the common (CO) connection and is connected to either the upper or lower terminal block depending on the state of the relay.

• Vital role of RELAY: Switch on/off the device according to the

microcontroller commands.

PCBPCB• A printed circuit board, or PCB, is

used to mechanically support and electrically connect electronic components using conductive pathways.

• electronic component have wire leads, and the PCB has holes drilled for each wire of each component. The components' leads are then passed through the holes and soldered to the PCB trace.

FLOW CHARTFLOW CHART

.

Yes

Yes

Yes

Yes

No

No

No

No

ValidCommand

?

SMS Received

?

Start

Modem Initialization

LCD Initialization

S

Sensor2?

READ SMS FROM SIM CARD & COMPARE WITH

DEFAULT COMMAND

DO OPERATION WITH CORRESPONDING COMMAND

Sensor1?

Delete SMS

Relay2Relay2

ON/OFF

Relay1ON/OFF

No

No

Yes

Relay1

Yes

S

Reading SensorStatus /SMS

Send SMSto Purticular Person

ADVANTAGESADVANTAGES• The status of various devices can

be monitored and controlled from anywhere.

• The operation of the system is very simple and can be used by anyone with a basic knowledge of operating mobile phones.

• Easy to upgrade as per the user requirement.

APPLICATIONSAPPLICATIONS

• Home Automation• Office Automation• Industrial Automation• To control water pump sets in

agricultural fields.• The security system can be

employed in household or any organization.

LIMITATIONSLIMITATIONS• If the main module or the

handset is not in the cellular range ,we can’t control the devices.

• The sensors use RF transmitter and receiver which has limited range, hence sensors have to be in close vicinity of the main module

FUTURE SCOPE OF FUTURE SCOPE OF WORKWORK

• It can be used for high security in banks and other organizations.

• Using real time clock, the appliances which need response in real time can also be Controlled through the wireless link .

• Connecting More Devices.• Provision To Store Several Mobile

Numbers • Video Recording Once Alarm Gets

Triggered

CONCLUSIONCONCLUSION• We presented an approach that can

be employed to improve the performance of various devices that are not in the close vicinity of the user.

• The usability of the design was verified by controlling a table fan and a table lamp.

• The user was informed about the action through a reply SMS sent by the modem at the receiver.

THANK YOU…THANK YOU…