International Journal of Engineering Trends and Technology- Volume3Issue3- 2012
Data Acquisition and Control System Using
Embedded Web Server
Soumya Sunny P1, Roopa .M2
1
M.Tech,ECE Department, DSCE Bangalore,VTU University,India
2
Asst.Proffesor,ECE Department, DSCE Bangalore,VTU University,India
II. EMBEDDED WEB SERVER
Abstract—This paper realizes an embedded web server,
which enables data acquisition and status monitoring with
the help of any standard web browser. User can monitor
and control remote temperature and video information
The platform used is Linux and ARM 9 processor. Biggest
advantage of this web server is embedding a PC based web
server into the ARM platform without losing any of its
features. It consists of application program written in C
for accessing data through the serial port and updating the
web page, porting of Linux 2.6.3x Kernel with application
program on ARM9 board and booting it from the RAM.
Keywords— ARM, Linux, Embedded web server.
I. INTRODUCTION
As the World-Wide Web (WWW) continues to evolve, it
is clear that its underlying technologies are useful for much
more than just browsing the web. Web access functionality is
embedded in a device to enable low cost widely accessible
and enhanced user interface functions for the device. A web
server in the device provides access to the user interface
functions for the device through a device web page. A web
server can be embedded into any appliance and connected to
the Internet so the appliance can be monitored and controlled
from remote places through the browser in a desktop. This
brings in a need for web services being deployed on various
embedded processors such as Advanced RISC Machine
(ARM) in real time context. Usage of Linux as the operating
system brings the advantage of performance, reliability,
availability and support from large developing community.
High performance ARM Processor further enhances the
quality of features offered by the web server.
This paper introduces a solution for embedded system access
to Internet, through which we can remote access, monitor,
maintain conveniently. The solution is based on Web and
embedded technology. Its core is S3C2440A processor on
which there embedded Web server in ARM Linux platform.
Its operating system is scissor-able, transplant-able Linux
system.
Embedded web server refers to import Web Server at the
scene the monitor and control equipment, in the support of
appropriate hardware platforms and software systems, transfer
traditional monitor and control equipment into an internet
based, possessed with TCP/IP protocol as the underlying
communication protocol and Web server technology as its
core[1].
General web servers, which were developed for general
purpose computers such as NT servers or Unix and Linux
workstations, typically require megabytes of memory, a fast
processor, a preemptive multitasking operating system, and
other resources. A Web server can be embedded in a device to
provide remote access to the device from a Web browser if the
resource requirements of the Web server are reduced. The end
result of this reduction is typically a portable set of code that
can run on embedded systems with limited computing
resources. The embedded system can be utilized to serve the
embedded web documents, including static and dynamic
information about embedded systems, to Web browsers. This
type of web server is called an Embedded Web Server
(EWS)[2].
The main use of EWS is to convey the current state
information of embedded systems, such as a system’s working
statistics, configuration and operation results, to a Web
browser. EWSs are also used to control or transfer user
commands from a Web browser to an embedded system. The
state information is extracted from an embedded system
application and the control command is implemented through
the embedded system application. Embedded web software to
be light weighted version of web software in many
instances. Embedded web servers have different requirements,
such as low resource usage, high reliability, security and
portability, for which general web server technologies are
unsuitable.
A. System Architecture
The entire system uses B/S (Browser/Server) mode for its
low development cost, flexibility, easy maintenance and
ISSN: 2231-5381 http://www.internationaljournalssrg.org
Page 411
International Journal of Engineering Trends and Technology- Volume3Issue3- 2012
upgrade. Compared with C/S (Client/Server) system, B/S
system does not require development of client programs so
that developers can concentrate on the development of the
Server and this mode is simple to use, convenient to maintain,
and easy to extend. The client PC is connected to the Internet
through a browser and then gets access to the embedded Web
server. Through this way, remote login and operation are
realized.
Fig 1. Shows the proposed concept of Data Acquisition and
Control Systems (DACS) with embedded web server. It
contains RTOS portable ARM processor. The real time
operating system manages all the tasks such as measuring
signals, conversion of signals, data base up-dation, sending
HTML pages and connecting/communicating with new users
etc.
The RTOS manages all the required tasks in parallel and in
small amounts of time. Web based management user
interfaces using embedded web server have many advantages:
ubiquity, user-friendly, low-development cost and high
maintainability.
Client1
Web
client via
internet
ARM
platform
Client2
Client3
Fig. 1. Embedded Web-Server architecture
III. SYSTEM DESIGN
A. The Hardware design
The general hardware structure of the remote data
acquisition and control system based on ARM processor is
shown in Fig 2. S3C2440 processor is used as core of the
hardware.
The main frequency of Samsung S3C2440 is 400MHz and
can up to of a peek frequency of 533MHz . JTAG (Joint Test
Action Group) is an international test protocol standard,
software simulation, single-step debug and vivi-boot
download can be carried out through the JTAG port, it's a
simple and efficient means of developing and debugging
embedded systems. The SDRAM capacity in the system is
64MB, working voltage is 3.3V, data bus is 32bit,and
SDRAM clock frequency can reach up to 100MHz.Flash
memory is divided into 64M NAND flash and 2M NOR flash
The S3C2440 CPU chip supports two kinds of boot modes:
booting at the NAND flash and booting at the NOR flash. The
allocation of the storage space of the chip selections is
different in the two boot modes. For supporting boot loader in
the NAND Flash a buffer named Steppingstone is present in
SDRAM. When the system get started, the first 4Kbyte
content in NAND Flash is loaded to the Steppingstone and be
executed. When Start up code, the contents of the NAND
Flash are copied to the SDRAM. Main program will be
executed from the SDRAM based on the completion of copy.
B. The Software design
Software development process based OS includes: the
establishment of cross-compiler, the creation of root file
system, the transplant of Boot loader, the porting of embedded
Linux, and the development embedded Web server. ARM
Linux gcc is the cross compiler used. Boot loader vivi is used
here. The function of Boot loader is to initialize the hardware
devices, establish memory mapping tables, thus establish
appropriate hardware and software environment, provides
interface to send commands to target board and prepare for the
final call to the operating system kernel. Linux is used as
operating system because Linux system is having a
hierarchical structure and completely opens its kernel source.
Linux can port to a wide range of hardware platforms, and can
run in most of the architecture. Linux has a comprehensive set
of editing, debugging and other development tools, graphical
interface, a powerful network supporting and rich
applications. In addition, the kernel can be reduced by
configuring it.
IV. TEMPERATURE AND ITS CONTROL
The data acquisition system reading the temperature from
the target board and transfer data through web server. The
user having the right administration password can view the
values and control and motor connected to the device. The
Linux sockets are used to communicate between ARM server
and webpage’s form clients. The communication between arm
platform and client board is by RS232 protocol. A PIC
microcontroller act as the CPU of the client board.
Fig 2 General Structure of the Remote DACS
We can connect ‘n’ number of client board to the main
system depends on the SCADA system requirement here we
implemented a temperature control board which is having auto
and manual modes. In auto mode the system will respond to
ISSN: 2231-5381 http://www.internationaljournalssrg.org
Page 412
International Journal of Engineering Trends and Technology- Volume3Issue3- 2012
the real-time temperature changes automatically and control
the motor for adjust the temperature in manual mode user can
control the motor speed in 0 to 9 levels.
The html web interface is used to monitor and control data .
This part is written using Linux sockets it made the
communication fast and simple compare to standard web
server packages.
V. VIDEO ACQUISITION
A. The Camera Driver
Linux kernel configuration for USB camera driver: Run
“make menuconfig” to configure the kernel, and select the
following options to support the Logitech hd webcam C270
Multimedia devices --->
<*> Video For Linux
[*] Video capture adapters --->
[*] V4L USB devices --->
<*> UVC based webcams --->
Fig 4.Page for invalid login
Then compile the kernel. Turn on the development board,
and update the kernel to the new one we just compiled. Insert
the camera into the USB port. If the terminal displays the
message new USB device found, indicates that the camera
driver has been successfully loaded.
B. Video Streamer
Used to stream JPEG files over an IP-based network from
the webcam to a viewer like Firefox, a Windows Mobile
device or mobile phone that has a web browser. The streamer
program has two major section the first part is the camera
application for capturing image and the next is the streamer
part using HTTP sockets.
Fig 5. Page to monitor and control temperature
VI. INTERFACE DESIGN
DIAGRAMS
Fig 6.Page for video monitoring
Fig 3.Login page
ISSN: 2231-5381 http://www.internationaljournalssrg.org
Page 413
International Journal of Engineering Trends and Technology- Volume3Issue3- 2012
VII.
CONCLUSIONS
The embedded web server that has been designed can be
used with industrial equipments medical instruments, and
in many other places. An administrator can monitor and
control the equipments with a simple but enhanced and
more powerful user interface without additional hardware.
Software contention and architectures can significantly
affect web server performance. Poorly designed and
configured software architectures might even generate
high response times while the physical resources display
low utilization. A remote user only requires a common
internet browser to carry out experiments on real hardware.
REFERENCES
[1]
[5]
Mo Guan and Minghai Gu, “Design and Implementation of an
Embedded Web Server Based on ARM” 978-1-4244-6055-7/10/$26.00
©2010 IEEE
Hong-Taek Ju, _ Mi-Joung Choi and James W. Hong “An efficient and
lightweight embedded Web server for Web-based network element
management” International Journal of Network Management, pp. 261
– 275, Oct 2000
Xiguang, Li Bonian, Zhao Likai, Zhang Jie, Zhang Minghu “An
embedded real-time remote monitoring system based on B/S mode”
978-1-61284-722-1/11/$26.00 ©2011 IEEE
Yakun Liu Xiaodong Cheng “Design and Implementation of
Embedded Web Server Based on ARM and Linux” 978-1-4244-7656511 01$26.00 ©201 0 IEEE
Installation Manual for S3C2440
[6]
Manivannan M , Kumaresan N. “Embedded web server & gprs based
[7]
advanced industrial automation using linux rtos” Vol. 2(11), 2010,
6074-6081, ISSN: 0975-5462
V.Billy Rakesh Roy, Sanket Dessai, and S. G.Shiva Prasad Yadav .”
Design and Development of ARM Processor Based Web Server”
International Journal of Recent Trends in Engineering, Vol. 1, No. 4,
May 2009,pp 94-98
[8]
“Building Embedded Linux Systems” By Karim Yaghmour
[9]
“Embedded Linux” By Chris Hallaughbagh
[2]
[3]
[4]
ISSN: 2231-5381 http://www.internationaljournalssrg.org
Page 414