Middle-East J. Sci. Res., 19 (12): 1623-1629, 2014
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Fig. 3: IP address lookup for the stored IP kernel series with TCP/IP stack included has been chosen
Fig. 4: Data management in the propsed system explained in Section III with a sample implementation.
named mozart (Fig. 2), can be queried from the FTP server other applications and is triggered once all the
by a simple command. The web browser processes the components of the operating system are up and running.
(index.htm) file in the specified folder as default; therefore, The periodic operations and routine tasks are organized
a file name is not needed for referencing. by a manager code. If a new data-access application is
This process is illustrated in Fig. 3. The DHCP considered in future developments, its program can easily
approach is more flexible and works better compared with be added to the manager code as a periodic operation.
the static approach as a cost-effective solution, despite
the necessity for a script running on the embedded CONCLUSION
server, one-time broadcasting its IP to the FTP server.
The hypertext file placed on the FTP server by the In this application, a low-cost, Internet-based data-
embedded system and queried by the client is shown in acquisition and control system has been designed and
Fig. 4. With this mechanism in place, the embedded implemented that should find interest from researchers.
system updates it IP information on the FTP server upon The Compared with other applications, this system has
every reboot, which causes an IP refresh from the GSM advantages in terms of allowing direct bidirectional
service provider. communication and reducing overhead, which can be
Data Management in the System: The Internet server is
used to decrease the management costs by sending all the
pictures (logo, picture, bar graphics, etc.) to the client
through a server on the Internet. Text data such as
coordinates, temperature and altitude are served from the
embedded system. If bulky data are going to be sent, the
embedded module is set to send the image only once via
GPRS and placed on an FTP server. This approach
eliminates the transfer of large data through GPRS more
than once, thus reducing the transfer costs, particularly if
more than one client is involved or multiple requests to
the same data are needed, as shown in Fig. 5. A user
interface, which is brought up upon establishing a direct
connection, has links to the Common Gateway Interface
(CGI) and Bourne Again Shell (BASH) script files
executed on the embedded system. The code is compiled
into the CGI format to be installed in the embedded board
through a cross-compiler platform. BASH scripts are
directly triggered by the applications.
Software and Operating System Choice: The Linux 2.4
as the operating system for the embedded board. Only the
bare minimum is installed, including the basics such as
console try, serial ports, kernel side of the PPPD and
support for memory and math emulation. The running
kernel is around 1 MB of code built into a Flash memory.
A scaled-down version of Linux has been used to reduce
the memory footprint and the complexity.
The software running on the embedded system at the
highest level is named the manager code, which will be
In the design, the manager code controls the execution of
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