Transcript Document 7601684

GENERIC CONTROL OF
ELECTRICAL
ENVIRONMENT THROUGH A
WEBPAGE
- IT Acumens. COM
AIM:
The aim of the project is to control
electrical devices from a remote
location through a web page.
SOFTWARE REQUIRED
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Java 2 Enterprise Edition(J2EE)
Java Development Kit (JDK1.3)
Apache Tomcat Server 1.4.1
Internet Explorer
Microsoft Access
Microsoft Word( for documentation)
HARDWARE REQUIRED
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Pentium III processor
64 MB RAM
10 GB Hard Disk
Operating system windows 98
PC Add-On card with PIA chip(s)
An External port board.
A dedicated designed interface
SCOPE OF THE PROJECT
CONTROL THROUGH IR
Range is limited.
Line of sight
CONTROL THROUGH MICROWAVE
Transmitter & Receiver are costly.
DESCRIPTION
The electrical devices that are to be
controlled are connected to the home
PC through a designed dedicated
interface.The status word of the
devices are posted to the PC through
the PIA present in the CPU of the
home PC.The status word is then
uploaded to the web server.
At the server the individual status of the
devices are decoded and posted to the
web page.A remote user logs in and
checks the current status of the devices,if
required the user changes the status of the
devices.The changed status is then posted
to the web server.The control word is then
encoded and posted to the home PC.The
changed status of the devices are
reflected.
STATUS DETECTING CIRCUIT
CONTROL CIRCUIT
8255 CHIP
• The 8255 chip is called a Programmable
Interface Adapter(PIA).
• The three buses used for the interface are
the address bus,data bus and the control bus.
• The 8255 contains three individual I/O
ports.
• The microprocessor connects to certain pins
on the 8255.
• Each port can be made to function either as Input
port or an Output port by setting the control word.
• Block B provides the logic for reading and writing
to each port of the chip.
The electrical status of the devices is retrieved
through the C++ program using the port-based
instructions.
The port-based instructions are
•
_inp (port number)
•
_outp (port number, value)
_inp is used to read the value from the port
and
_outp is used to write the value to the port.
START
SELECT
THE DEVICES
TO BE CONTROL
CONNECT THE
DEVICES TO THE
HARDWARE
INTERFACE
A
CONNECT THE INTERFACE
TO THE PIA IN THE PC
USING THE PORTBASED
INSTRUCTIONS RETRIEVE
THE STATUS WORD
IS THERE A
CHANGE
IN STATUS WORD
A
UPLOAD THE CHANGED
STATUS WORD TO
THE SERVER
THE STATUS WORD IS
DECODED AND IT IS
STORED IN DATABASE
IN THE SERVER
THE REMOTE USERS
AUTHENTICATION IS
CHECKED
IS THE USER A
NO
AUTHENTICATED
USER
DIRECT THE USER
TO A
RE-LOGIN PAGE
NO
IS THE USER
ADMINISTRATOR
DOES
THE USER HAVE WRITE
PERMISSION
C
YES
DIRECTED
TO THE
ADMINISTRATOR PAGE
C
DIRECT THE USER
DIRECT TO THE
TO THE DISPLAY
CHANGE STATUS PAGE
STATUS PAGE
THE USER CHANGES
O
THE STATUS AND
SUBMITS THE FORM
THE ENCODED VALUE
IS WRITTEN IN
THE SERVER
THE CONTROL WORD
IS POSTED TO
THE HOME PC
THE CONTROL WORD
IS SENT TO THE
OUTPUT PORT OF PIA
THE CHANGED STATUS
O
IS REFLECTED ON
THE DEVICES AT HOME.
STOP
MODULES
• Retrieving status word from the electrical
device.
• Posting the control word to the web server.
• User authentication and display of current
status.
• User changing the status of the required
device.
• Control word stored in the home PC.
• Reflecting the changed status on device.
ACQUIRING DEVICE STATUS
• The electrical devices are connected to the
interface designed.
• The interface is connected to the home PC
through a Peripheral Interface Adapter.
• The Status word is obtained through a flat
cable connected from the PC to the port
board.
• The value is then posted to the server.
DECODING
• A Servlet program is written to decode the
status word.
• The current status of the device are posted
to the web page.
ADMINISTRATOR
• The administrator has the rights to
add/delete the users from/to the list.
• The administrator categorizes the users
with two permissions
* Read permission.
* Read /write permission.
REMOTE USER
• Authenticated users are allowed to access the web
page.
• The users with read permission can only view the
current status of the device.
• The users with read/write permission can view as
well as change the status of the device.
• The changed status is stored in the web server’s
database.
TRANSACTION OF DATA
ENCODING CONTROL WORD
• The status stored in the database are
encoded using a servlet program.
• The encoded value is a decimal number
which varies from 0 to 255.
• The encoded control word is posted from
the web server to the home PC.
AT THE HOME PC
• The encoded control word is send to the
interface through a java program.
• Decoding is done in the interface as a result
of which individual device status are
changed.
OUTPUT SCREENS
LOGIN SCREEN
CURRENT STATUS
REQUIRED STATUS
DATA STORED