This document describes a system to remotely monitor and control devices using GSM technology. The system uses a GSM transmitter and receiver along with a microcontroller. Users can send SMS messages to turn devices on or off, check statuses, and receive notifications. The system provides advantages like remote monitoring and control. Potential applications include home, office, and industrial automation as well as agricultural equipment control and security systems.

1. Monitoring andMonitoring and
ControllingControlling
of Devices Usingof Devices Using
GSMGSM
By:By:
PriyankaPriyanka
(ECE)(ECE)

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

3. 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..

4. 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.

5. BLOCK DIAGRAMBLOCK DIAGRAM
RF TRANSMITTER RF RECEIVER
GSM TRANSMITTER
GSM RECEIVER
RF
Receiver
M
I
C
R
O
C
O
N
T
R
O
L
L
E
R
(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

6. 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.

7. 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/DCADOPTOR
REGULATOR
7805
FILTERS
ACPOWER DCOUTPUT

8. 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.

9. 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

10. COMMANDS FOR SMSCOMMANDS 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#

11. 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.

12. 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.

13. EEPROMEEPROM
• 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

14. 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).

15. 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.

16. 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

17. FLOW CHARTFLOW CHART
.
Yes
Yes
Yes
Yes
No
No
No
No
Valid
Command
?
SMS
Received
?
Start
Modem
Initialization
LCD
Initialization
S
Sensor
2?
READ SMS FROM SIM CARD &
COMPARE WITH
DEFAULT COMMAND
DO OPERATION WITH
CORRESPONDING COMMAND
Sensor
1?
Delete SMS
Relay2
Relay2
ON/OFF
Relay1
ON/OFF
No
No
Yes
Relay1
Yes
S
Reading Sensor
Status /SMS
Send SMS
to Purticular Person

18. 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.

19. 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.

20. 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

21. FUTURE SCOPE OFFUTURE 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

22. 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.

23. THANK YOU…THANK YOU…