02-07-2012, 02:45 PM
Project on GSM Based Control System
GSM Based Control System.pdf (Size: 245.38 KB / Downloads: 569)
Introduction to Project
“GSM based Control System” implements the emerging applications of the GSM
technology. Using GSM networks, a control system has been proposed that will act as an
embedded system which can monitor and control appliances and other devices locally
using built-in input and output peripherals.
Remotely the system allows the user to effectively monitor and control the house/office
appliances and equipments via the mobile phone set by sending commands in the form of
SMS messages and receiving the appliances status. The main concept behind the project
is receiving the sent SMS and processing it further as required to perform several
operations. The type of the operation to be performed depends on the nature of the SMS
sent. The principle in which the project is based is fairly simple.
Background
The new age of technology has redefined communication. Most people nowadays have
access to mobile phones and thus the world indeed has become a global village. At any
given moment, any particular individual can be contacted with the mobile phone. But the
application of mobile phone can not just be restricted to sending SMS or starting
conversations. New innovations and ideas can be generated from it that can further
enhance its capabilities. Technologies such as Infra-red, Bluetooth, etc which has
developed in recent years goes to show the very fact that improvements are in fact
possible and these improvements have eased our life and the way we live. Remote
management of several home and office appliances is a subject of growing interest and in
recent years we have seen many systems providing such controls.
Scopes and Purpose of System Specification
The system specification shows the description of the function and the performance of
system and the user. The scope of our project “GSM Based control system” is immense.
The future implications of the project are very great considering the amount of time and
resources it saves. The project we have undertaken can be used as a reference or as a base
for realizing a scheme to be implemented in other projects of greater level such as
weather forecasting, temperature updates, device synchronization, etc. The project itself
can be modified to achieve a complete Home Automation system which will then create a
platform for the user to interface between himself and the household.
ATMEL Micro-controller
The AT89C52 is a low-power; high performance CMOS 8-bit microcomputer with 8K
bytes of Flash programmable and erasable read only memory (PEROM). The device is
manufactured using Atmel’s high-density nonvolatile memory technology and is
compatible with the industry-standard 80C51 and 80C52 instruction set and pinout. The
on-chip Flash allows the program memory to be reprogrammed in-system or by a
conventional nonvolatile 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.
Temperature Sensor
The two main types of semiconductor temperature sensors are temperature sensitive
voltage sources and temperature-sensitive current sources. An example of the first type is
the National LM35. The voltage output from this circuit increases by 10 mV for each
degree centigrade that its temperature is increased. If the output is connected to a
negative reference voltage Vs, the sensor will give a meaningful output for temperature
range of -55 to +150 degree centigrade. The output is adjusted to 0V for 0 degree
centigrade. The output voltage can be amplified to give the voltage range we need for a
particular application. The accuracy of this device is about 1 degree centigrade.
Nokia 3310
Most Nokia phones have F-Bus and M-Bus connections that can be used to connect a
phone to a PC or in our case a microcontroller. The connection can be used for
controlling just about all functions of the phone. This bus will allow us to send and
receive SMS messages. The very popular Nokia 3310/3315 has the F/M Bus
connection under the battery holder. The picture below shows the 4 gold pads used
for the F and M Bus.