Embedded Web Server - Essay Example

Table of contents Introduction to Web Server (a) Aims and objectives 2. Required Equipments 3. Main component (a) Printed circuit board (b) Construction of a printed circuit board (c) Features of a printed circuit board 4. Problem Analysis and Solutions (a) The process of testing printed circuit board (b) Safety measures to be employed (c) Protection and packaging process (d) Peculiarities in a PIC WEB PCB (e) Testing of PIC boards 5. Uploading of web pages 6. Result 7. Conclusion 8. Reference sources 1. Introduction to Web Server: Web server is a program in computer devices which is capable to provide a web page to the user of the device. In another words this is the system which can serve the internet with suitable web page or web site. The Embedded Web Server is the software unit of a system which can provide the website by receiving the Hypertext Transfer Protocol (HTTP) symbols from the browsing units. The commonly using Protocol is the Transmission Control Protocol (TCP) which is a high quality data transferring system. This system assures connection between two partners and is capable to provide a guaranteed safeguarded communication system. (a) Aims and Objectives: The main intension of this essay is to make the user fully aware with the Web Server. Since this is a commonly dealing device it will be helpful for the user to have knowledge with respect to the process of assembling and working of the Web Server. Hence the user must get acquainted with the main part of the device called Printed Circuit Board. To have the desired result it will be better to provide the subject by describing certain components of the web server perfectly. The systematic process of dealing the subject can be shown by the problem diagram given below. 2. The Required Equipments: For the construction of a Web Server the mainly required devices are direct current Voltage regulator, soldering pen, driller and multi-meter. 3. The main component: (a) Printed Circuit Board: In order to make a detailed study of the Internet Embedded Web Server, first we have to get acquainted with various subsidiary devices of the main system. Printed Circuit Board (PCB) is one among them. This is considered as an integral part of the Internet Web Server Unit. The printed circuit board is the printed wiring board which is commonly used to manufacture electronics devices. (b) Construction of a Printed Circuit Board: The PCB is an electronic device having two roles. Mainly it is the platform to assemble the components in an electronic device which has got high capability to provide electrical connections among the components. This consists of a non-conducting fiber glass sheet with bonding materials. This material is lined with very thin copper layer by means of some chemical process. Next task is to print the diagrammatic connections on the circuit board. This is a sketch with respect to the wiring connections to be followed in order to assemble the components. Hence the PCB can also be referred as the printed wiring boards. In previous days these connections were performed with the help of wires only. By applying photographic energy in transferring the images to PCB the printing process can be achieved very successfully. Naturally an acid resistant material is employed for printing the circuit diagram. Then this PCB is to be subjected for an Acid bath by which the copper lining on the board can be removed partially. The copper lining protected by means of the acid resistant material remains unaffected with the acid bath. Thus the connections get printed on the PCB. Next is to create some holes on the board. These holes are meant for mounting the components on the PCB which in turn needs to be mounted on a separate case which is considered to protect the electronic components as a whole. Then a coating is to be applied on the whole board in order protect the existing copper from corrosion. The Diagram shown below is capable to provide a clear picture of Printed Circuit Board. If all the above process is successful then it will be very easy to develop a double sided printed circuit board. The double sided PCB has got wiring components on both sides of the insulated circuit boards. Here the PCB is capable to provide circuits on solder side as well as on the component side. In this type the density of the components and the lines of the conductor are more than a single sided PCB. Now it has become a common factor to solder the parts to the board in a view to avoid holes into which lead wires from the component are kept joined. Thus, the components mounted Printed Circuit Board is called 'Surface Mount PCB'. The Surface Mounting requires higher quality control capacity so that a better performance in the manufacturing process PCB can be projected (c) Features of a Printed Circuit Board: The PCB consists of a number of layers which are either electrical or non electrical in nature. In a printed circuit board there will be two to four electrical layers. For industrial purpose, eight to twenty layers of electrical layers can be seen in one PCB. The Diagram shown below will be helpful to understand the electrical layers with respect to a PCB. Figure 1 The top and bottom layers are employed to provide routs between parts soldered in the platform of the PCB unit. The inner two layers are constructed by means of copper plates and capable to provide connections between ground and power system. In the platform each of these multilayers is separated by means of fiberglass material which is dielectric in nature. The non electrical layer of a PCB also consists of numerous parts. They are Drill layer, Solder mask, Solder paste and Silk screen. The drill layer consists of numerous locations having well defined holes through which pins of the parts are inserted. It can also be used for the information purposes. Solder mask is the lining or coating found on the upper and lower sections of a PCB which is capable to protect the free flowing of the solder. Hence the presence of the circuit board imparts a green color to the circuit board. Another layer called solder paste is not meant for constructing the PCB. It is commonly employed to assemble the circuit. Here the solder paste is applied to provide better circuit connection among pins of the components present on a PCB. Silk screen is the layer which is also used for the purpose of providing information with respect to PCB and its circuits. All useful information regarding reference, designation and connections would have marked either on top or bottom side of the PCB. If the printed circuit boards are not to be used immediately they should be protected perfectly by storing them in suitable plastic bags. 4. Problem analysis and solutions (a) The process of testing Printed Circuit Board: Electrical as well as visual inspections are to be carried out so perfectly throughout the process of construction of the PCB. This is essential for the timely detection of faults which may be aroused during the process of construction of PCB. Certain blemishes are developed from machineries itself from the automating and functioning. In this type of mistake the parts belonging to a PCB may be kept unsuitably on the board or transferred before subjecting to the process of soldering. Other common defect usually come across is the usage of excess of solder paste. This results excess flow of solder in certain cases or develops connection between two nearby printed circuits. The process of heating solder quickly in the final stage causes the components get lifted from one end of the board and results loose contact. The PCB should also be subjected to the process testing with respect to its performance in functioning. This is to make sure that the out put of the PCB is with respect to the required limit. Another test need to be conducted is the assessment of environmental based functioning of the PCB. This is to ensure their performance during adverse circumstances like excess heat, impact, vibration and humidity. (b) Safety measures to be employed: There are toxic materials in the soldering components of the PCB. The materials commonly using to provide electric connections between components contain the toxic constituent Lead. The fumes creating problem from the solder points of PCB has been creating a massive health problem to human beings. Since this is harmful to health and environment the soldering process should be carried out from an enclosed area. The fumes are advised to store and purify before being ejected to the atmosphere. Another problem is the timeframe regarding the PCB. The electronic products bearing PCB becomes out of use within a time frame of eighteen months. The potential existing in such products are responsible for numerous environmental problems. The environmentalists are very much concerned about these problems. In certain countries there are rules to recollect the electronic products by its manufacturers and to convert them to safer product before disposing. In order to overcome this difficulty the manufactures either remove or neutralize the toxic soldering component from the PCB. Since this process is so expensive researches are in progress to find out an alternative to this difficulty. The scientists aim is to find out a PCB with harmless circuit connections. Now they are at the brink of a successful attempt to develop plastic molded electrical conductors which are water soluble. According to researchers the plastic molded conductors are the suitable and safe alternatives for the currently using solders and wires. (c) Protection and Packaging process: The PCB is provided with certain special type of coating in order to overcome the adverse environments. Here the coating is provided by subjecting the components to be soldered either by dipping or spraying. This coating protects the circuit board from shortage of current due to condensation, corrosion and loosing of current because of leakage. Formerly the coatings were undertaken with the help of waxy materials. But currently the process of coating is performed by dipping the components in mildly concentrated solutions of Polyurethane, Epoxy, Acrylic and Silicon rubber. In certain cases special types of plastics are used to coat the PCB from vacuum containers. Since the newly constructed PCBs are statically very sensitive care should be taken to accommodate them in special bags which are antistatic in nature. Another important matter to be considered is that the person who has to utilize the Printed Circuit Board must be properly earthed or grounded in every occasion. Improper and careless handling of the circuit board will develop blemishes on the components mounted on board. This will result to change the characteristic features of the PCB as a whole. (d) Peculiarities in a PIC WEB PCB: PIC is an electronic microchip technology which provides a vast usage with the micro controllers. In a PIC board PCB the PIC board is to be designed in advance. Commonly there are two designs to follow for a PIC board construction. In the first category of the PIC board construction op-amp was used as a buffer. But later it is understood that the op-amp is not capable to produce the desired outcome. Hence, apart from using lm741 op-amp buffer, MM74C90X buffer is found more beneficial. The second design can be developed by producing very minor changes in the first design. This can be attained by incorporating an extra ground pin into the board. A sample Diagram of PIC board is shown below. The above diagrams of switch board and Power Regulators will be helpful to develop a better awareness about the concerned subject. In order to ensure a very good performance the PIC board should be assisted with a switch board. The switch board is accommodated with switches which are capable to control various lines having current loads. It also contains various sensors to supervise variable loads of current and voltages. The problems often found with PIC board are regarding Buffer. This will be due to the wrong connection with the power rail. To overcome this difficulty it should be connected to the suitable power rail through proper channel. Naturally if the buffer is connected to 3.3- volt power source the switches can be worked properly producing better performance. (e) Testing of PIC boards: The process of testing the PIC boards are very important as well as the testing of PCB. PIC boards are tested for confirming whether the components mounted on the board are in proper manner. Next is to inspect the sensors. If any problem is found with the sensors that can be tackled by providing extra wiring if needed. Then make a thorough checkup with respect to the operation of the whole system and see whether the outcome of the operation is coinciding with the theoretical aspects provided. 5. Uploading of web pages: Web pages are purely meant for the user. They are independent programs. They can be stored in the memory capacity of the system. This can be stored either in folders or files. The memory capacity of the system is divided into six portions and each portion with 64K capacity. The file having capacity larger than this volume will be skipped naturally. Hence the user should have awareness regarding the size of the web page and that should not exceed 384K. This calculation will be helpful to avoid complications during the process of storing of the web pages. Next is to convert all files into COB file and store them in the X-Port. To achieve this process the user has to download the MAKE COB folder. After the process of downloading the user has to copy all the contents in the C drive. Usually the MAKECOB folder is formed by means of four files. Another folder called source folder can be used by the user to transfer his personal web page, so that he can abandon the existing folder. The above diagram points out the web page files copied to C drive (MAKECOB folder). 6. Result: - For representing the demonstration of Printed Circuit Board and internet web server the user can employ internet explorer window and personal web page. The personal IP address can be clearly mentioned in the personal web page. Then the user has to take the stored web page of the of the COB file. Now as desired the main page of the personal web page can be viewed on the screen. 7. Conclusion: In this essay we have dealt with embedded web system and Printed Circuit Board. The process of constructing the PCB is really a task. But if the instructions are followed carefully one can easily assemble the parts and develop a positive outcome instantly. This essay is capable to provide a very good knowledge to the reader regarding the embedded web system with PCB. We have done our best to make this essay so simple so that the reader can grasp the contents so easily. We have also provided necessary diagrams to make the awareness process so easier. Hence we hope that the reader need not take too much effort to make the matter easily get digested. 8. References 1) John ,Sunshine ,What is a PCB http://www.wisegeek.com/what-is-a-pcb.htm (2003) 2) John Hewes Printed Circuit Boards http://www.kpsec.freeuk.com/pcb.htm(2009) 3) copper printed circuite board http://www.robotroom.com/PCB.html 4) Alexander Yerezeyev 8 bit embedded web server http://alyer.frihost.net/web_server.htm ( 25 Feb 2009) 5) allankliu, embedded web service http://dev.emcelettronica.com/embedded-web-services (Jun 25th, 2008) 6) Integrated printed circuit board and test contactor for high speed semiconductor testing http://www.patentstorm.us/patents/7173442/description.html (feb 2007) 7) Frantz, patric, denia , fernmadaz printed circuite boards http://cnx.org/content/m11834/latest/( feb 18 2004) 8) Braithwaite, Nicholas and Graham Weaver, eds. Electronic Materials. Butterworths, http://www.answers.com/topic/circuit-board (1990) 9) c++ web embedded http://www.codeproject.com/KB/IP/webem.aspx 10) secure device control http://barracudaserver.com/ 11) Sid,Wentworthan, Embedded Web Server http://www.linuxjournal.com/article/4773(July 1st, 2001 ) 12) PIC Micro Web http://www.olimex.com/dev/pic-micro-web.html 13) embedded single board computer http://www.modtronix.com/product_info.phpproducts_id=102( may 2004) Read More