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Submission Form for Final-Year
PROJECT REPORT Ê
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Malik Husnain Riaz
Bte-sp08-25/A
[email protected]
M.Hussaan Saeed
Bte-sp08-31/A
[email protected]
S.M.Jawad Azeem Rizvi
Bte-sp08-47/A
[email protected]
Siraj ul Haq
Bte-sp08-53/A
[email protected]
#$ %Ê Number of pages in this report I/We have enclosed the soft-copy of this document along-with the codes and scripts created by myself/ourselves My/Our supervisor has attested the attached document '(Ê) *ÊÊÊ!Ê! Ê+ ,Ê Ê) Ê) *ÊÊ+Ê)Ê+- *ÊÊ* Ê)Ê + -!Ê* ÊÊ
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Supervisor¶s Signature ! " # $ % !
This work, entitled ³GSM Based Faculty Student Console´ has been approved for the award of Ê
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Date 23-12-2011
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In the name of God, the most kind and most merciful, without His blessing it cannot be possible for us to complete our project ³GSM based faculty student console´. May He bless us with all the resources and the guidance for making us able to work for the welfare of humanity.
We would like to thank our parents and our all other family members who kept backing us up in all the times, both monetarily and morally«
We are grateful to our project advisor "Ê Ê ! for his constant guidance, support, friendly behaviour and encouragement for working hard made us able to achieve this milestone. His critical views were the most helpful thing while doing this dissertation work and the project.
We are thankful to our class mates for their assistance, advices and group discussions. Their help directly or indirectly was really supportive for this task completion.
Ê
Wireless communication was always been a challenge for scientists but as technologies evolves scientists and engineers have defined new dimensions for themselves. Their main emphasis has now gone to create products for making human life unproblematic as it was never before. This project is one of those projects that help others to think about serving humanity in this new way i.e. the ease of communication in the academic scenario. This project is on the subject of wireless transmission of personal data keeping privacy and time saving aspect alive. This project illustrates why and how GSM technology is being used for the purpose of time saving and privacy. This system accomplishes two main functions, one is the short message delivery and the other is the transmission of e-mail. This system resembles to a cellular phone with privacy as its main intention. This system is a user friendly system. Since this project is dedicated to academic purpose, user don¶t need to have teacher¶s cell number or e-mail address to send SMS or mail respectively. Sometimes teacher vacillate to share its personal contacts with students that causes a communication gap between these two classes. This project utterly resolves this issue with efficiency and speed. This project will open new path and school of thought for the new generations to follow.
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GSM/GPRS TECHNOLOGY ..................................................................................................... 4Ê
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SUMMARY ............................................................................................................................. 7Ê
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SYSTEM OVERVIEW ................................................................................................................ 8Ê
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METHODOLOGY ..................................................................................................................... 8Ê
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INPUT AND OUTPUT MODULES .............................................................................................. 10Ê
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CONTROLLER ....................................................................................................................... 10Ê
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GSM M ODULE ..................................................................................................................... 10Ê
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SYSTEM INTEGRATION .......................................................................................................... 17Ê
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CONCLUSION........................................................................................................................ 23Ê
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0Ê Ê As wireless technology is growing rapidly, people are anticipating much more product outputs from this technology. This project is solely wireless communication based project that meets all the requirements of the modern world. It provides communication between a faculty member and a student keeping faculty member¶s personal information hidden. The main aspiration of the project is to investigate how GSM technology plays the important role of making human life easier. This project has been dedicated for student faculty wireless console. Student can communicate his teacher at any time without knowing his number or email address. This provides wireless connectivity 24/7. The
research
includes
devising
possible
improvements
in
student-faculty
communication system. Student faculty communication has an important impact on our educational system. In those environments where there is less interaction between teachers and students there possibly have less chances of knowledge transfer from teachers to students. For instance, on occasion a student has a query in his mind he just walk off straight to his teacher or advisor to talk about that but the teacher was not available at that time, what he would think? Student may think: I should try again later. But if he get continues failure in that because of office timings or any other problem he may become hopeless. Student may give it up forever. Student may think that he is not worthy enough to talk to a teacher. All these problems create doubts in student¶s mind that leads to low standard education and non creative thinking. This phenomenon happens quite often in common life and this project is the simplest solution to this problem. This project primarily provides two options to the user; one is to send SMS using keypad or to send E-mail. Keypad used here works just like a cell phone¶s keypad. Student will type his message and send to the destination address that has already been stored in the system. So the teacher¶s privacy will remain intact. Architecture-wise this project consists of an LCD and a keypad. Internally, there is a microcontroller based central processing unit, and a GSM modem. Microcontroller will control all the inputs and functioning of our system, while the GSM modem will work to deliver SMS and mail as programmed in the microcontroller. In this project PIC18F452 is used as microcontroller based central processing unit and SIM900D as GSM modem. This system will be placed outside teacher¶s cabin.
The project includes development of software to use GSM modem for transmitting and receiving data, the programming of LCD such that it will print all characters on screen in order and the programming of keypad such that it will behave like a cell phone¶s keypad. Mobile keypad works in such a way that if we press first button it will show a dot but pressing it again within limited time it will print , or any other symbol as programmed. Similarly for Alphabets: if a student press µa¶ button once it will be displayed on screen but within given time if user press it twice or thrice you¶ll get µb¶ or µc¶ respectively. To send the message there is a little different scenario as compared to the scene of sending a mail. Both, obviously, requires a different set of AT commands to operate. In case of SMS one should apply such commands on GSM modem to make it in writing mode (as discussed in appendix source code). Similarly for accessing a web page for the sake of mail transmission one needs a set of AT commands. Some of the main advantages of this project are: ÷Ê Short message delivery ÷Ê E-mail delivery ÷Ê Wireless connectivity 24/7 ÷Ê GSM technology is a reliable way to connect wirelessly ÷Ê Time saving, privacy, reliability and a user friendly device is the main theme of the project ÷Ê Use of GSM modem for the purpose of connecting our device to the GSM network and enable it for transmitting /receiving data ÷Ê Use of Microcontroller PIC18f452, cheaper in cost and it can be re-programmed up to 100,000 times. This controller requires just 5v battery, 4 MHz crystal oscillator and 22pF capacitors so that it can start its work ÷Ê Learning aspect: core electrical engineering concepts are involved. ÷Ê Portable integrated system, because of its compact size, portability is easier. You can use it anywhere you desire. That will enhance its acceptance at industry level ÷Ê Easy conversion to other useful systems like electronic notice board and complaint box
1Ê Ê (Ê 1"0Ê 7- Ê Basically one of the core objectives of this project is to replace manual system. Display digitally gives a better preview. In this modern era there are just countable things left in our lives that works manually, all other things have been changed according to the style of modern age. This project is based on digital wireless communication of data, work faster and cheaper in cost. In markets this technology has not yet been used, so one may call this an entrepreneurial thought. 1"0"0Ê 7Ê 8Ê There are some devices available in market that uses almost the same technology and similar in purpose. But they are either too costly, inefficient or rarely used devices. Efficiency always matters in electronics. The proposed device has to be less power consuming, providing long ranged operation as the consumers would like. Notice board that may work digitally is one of the similar devices to this device. Other device may be a security system that works on GSM. Notice board, for example, is a very costly device with just a purpose to show important notes, replacing a manual notice board is not acceptable device. Above mentioned project has no other application then representation of data in digital form. It will use almost the same resources as the project student console. But the project student faculty console has variety of applications available. It can even be turned to a digital notice board with a little modification, so the cost on it can be justified. 1"0"1Ê !- ÊÊ With the evolution of technology, GSM usage rates are declining considerably. This provides great ease for all the type of consumers to afford it. This device is also so much user friendly, everyone who knows how to use a mobile phone can use it without any difficulty. Even for lay men it is so easy to use; people just need one time briefing for how it works.
1"1Ê ( Ê!-Ê Wireless communication is the transmission of information between two or more stations that are not connected using any physical media i.e. cables. For long distance
wireless communication word telecommunications is used. Benefit of wireless communication is that we are able to transmit our data where there is not the possibility of cables. [1] Ê 1"1"0Ê Ê)Ê9 Ê!-Ê There can be many uses of wireless technology, the prime uses may be Information access and distribution, PDAs, Network computers, Web usage, Audio and video transmission. 1"1"1Ê Ê** Ê Basic cellular system is made up of three types of systems 1-mobile stations 2-base stations 3-mobile switching centre (MSC) Mobile station is built in portable device which contains a transceiver; base station is used to connect all mobile users in a cell to the MSC using microwave link or PSTN.
1"2Ê '£ Ê!-Ê Global system for mobile (GSM) is 2G standard for cellular systems. It was the world¶s first cellular system that uses digital modulation. From user point of view the most prominent feature of GSM was SIM (subscriber identity module). SIM is a memory device that stores user information and hence gives uniqueness and identity to all GSM cell phones. Other feature may be the privacy while data is going through air. General packet radio service (GPRS) is basically a packet based system and it is commonly used for non real time internet surfing including the retrieval of email, asymmetric web browsing as well as faxes. Asymmetric web browsing refers to the way of internet usage in which we can download much more data as compared to upload. GPRS supports multi-user network sharing of individual radio channels and time slots unlike HSCSD, GPRS can carry many more users than HSCSD, but in burst manner [1]. 1"2"0Ê £Ê Simple mail transfer protocol (SMTP) is a protocol used for email over internet. Email submitted by mail client to mail server using TCP and port 25. Detail of SMTP protocol is given below.
First client is connected to the SMTP server. There are few mail headers and commands send by the client in SMTP protocol. [9] HELO Sender Host Name\r\n MAIL FRM:
[email protected]\r\n RCPT TO:
[email protected]\r\n DATA\r\n SUBJECT: \r\n \r\n .\r\n QUIT\r\n 1"2"1Ê Ê**Ê GSM modem is basically a focused type of modem which works on GSM network using SIM card. This modem is quite similar to the mobile phone as it allows short messaging as well as internet connectivity. We have used SIM900D GSM modem for communication purpose in our project. It works on GSM 850 MHz, EGSM 900MHz, DCS 1800MHz and PCS 1900MHz.
1"DÊ Ê**Ê AT commands are used to communicate with GSM modem these commands are forward to modem serially then modem perform actions accordingly. Syntax to write AT is: The "AT" must be set at the start of each Command line. To terminate a Command line enter . All these AT commands can be divided into three types: ³ ´, ³ Ê + * ´, and ³/´ [7]. These are as follows: 1"D"0Ê Ê/ÊÊ These AT commands have the syntax like ³AT´, or ³AT&´, where ³´is the Command, and ³´is/are the argument(s) for that Command. Basically these Commands do not start with ³+´ sign e.g. ATD: For Dialing a Number ATE: For setting Echo. ATA: For answering a call.
1"D"1Ê Ê+ * Ê/ÊÊ These AT commands have the format of ³ATS=´, where ³´ is the index of the S register to set, and ³´is the value to assign to it. ³´ is optional; if it is missing, then a default value is assigned. 1"D"2Ê /Ê/Ê These commands are written in several modes. First is test command which is written as AT+=? And response to this command is The mobile equipment returns the list of parameters and value ranges set with the corresponding Write Command or by internal processes. Second is read command whose syntax is AT+? And response is This command returns the currently set value of the parameter or parameters Third one is Write command syntax for this one is AT+= and in response this command sets the user definable parameter values Fourth one is Execution command which is written as AT+ and in response the execution command reads non-variable parameters affected by internal processes in the GSM engine Extended Commands start with a ³+´ sign e.g. AT+CMGS: Send SMS AT+CMGF: Select Message Format AT+CPMS: Preferred SMS Storage AT+CMGD: Delete SMS
1"·Ê -Ê8 Ê 1"·"0Ê Ê A microcontroller is a single chip device on which a microprocessor is integrated with components of a microprocessor system like RAM (Random Access Memory), ROM (Read Only Memory), I/O (Input Output functions) and various other circuits. The onboard system used here is a PIC 18f452 microcontroller. It features 256 bytes of EEPROM data memory
[4]
and it is programmable. All of its features make it ideal for
more advanced level A/D applications in the industry.Ê
1"·"1Ê ) -Ê Interfacing is basically a transfer of information by synchronising different devices; we did these major interfaces in our project:
÷Ê Interfacing of different components with microcontroller ÷Ê Data transfer of SMS using GSM modem ÷Ê Data transfer of mail using GSM modem with AT commands 1"·"2Ê Ê** Ê Serial communication is used for testing project on computer. Built-in software of windows XP named hyper terminal is used for this purpose. One needs to synchronise a computer with the other connecting device in order to send or receive data. For this purpose, baud rate is set between the two communicating devices. Baud rate is the rate of communication as in serial communication data is sent bit by bit. Another important thing to mention here is the use of level convertor. For serial communication we have to manage the transmit power levels, for that particular reason the IC max232 is used.
1"4Ê ** Ê Since wireless technology is the main emphasis in this project, the above mentioned literature has the key importance in developing this idea into the real form. There is nothing available in market that is comparable to this device in terms of range of operation, cost and efficiency. It¶s a learning based project using all the concepts of technical subjects of electrical engineering that includes electronics, wireless data communication and microprocessors as the main insight.
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2Ê *Ê -Ê In this chapter a complete architecture of device is explained. The core element of our design is controller and all other components are interfaced with it. The design consists of three main parts in first part input and output modules are interfaced with controller, second part consist of communication with GSM modem and third one is for testing which consists of serial communication through hyper terminal, by which at commands are tested easily and easily implemented
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2"1Ê !-Ê Project has divide into five different phases of completion. First phase is of gathering all the information about this project, the components used and also reviewing the literature. Second phase comprises of testing and interfaceing of output module used in this project. In third phase input module is tested and interfaced. Fourth is the main phase of this project in which the wireless communication module is tested and interfaced with central controller through set of defined commands. In this phase all the other componets which are tested separetly also interfaced with central controller. With the completion of this phase the objectives of project are achieved. Fifth phase is
dedicated to written work organization and summerization which is started with the first phase. Fifth phase is converting all work done in this project into written form. This phase was initialized from the very first day. Compilation of all results and arranging all methods used in project implementation onto a document took some time as well
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2"2Ê +ÊÊ+Ê*ÊÊ Input block gives text formate input to the controller. This bolck control functions performed by the controller and provide an human interface. User provides data that he wants to send through this input module. Output block was used to display data input by the user. This module provides a visual of action performed by the user.
2"DÊ Ê This block provides processing of inputs given by the user and perform action accourding to these input. Controller also give instruction to the output module to provide visual to the user.
2"·Ê Ê Ê GSM module was use to communicate over the GSM technology. This module controlled by the controller, on the bases of the inputs given by the user. User selection configures the functionality of this module either mail or message. .
DÊ *+* Ê This chapter describe implement procedure of the project. How components are interface with the centralize controller.
D"0Ê Ê*+Ê The main components for input output and control are given below:
D"0"0Ê ;Ê Ê Action performed by the controller describe in pervious chapter was done with the help of PIC microcontroller.
PIC microcontroller is used as processing unit. It controls all the inputs and output. PIC family have a large number of controllers. Microcontroller used here in this project is PIC18F452. This microcontroller helps multiple peripheral devices to handle at the same time without multiplexing [4]. Input module was connected with PORTD and output module was connected with the PORTB. Third component which is GSM module was connected with the port dedicated for the serial communication.
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D"0"1Ê +Ê*Ê First display module is implemented using Liquid Crystal Display (LCD). LCD is a visual display device used to display different types of data e.g. Characters, graphical etc. The LCD found suitable for this project is a character LCD which shows 16characters per line in 2 lines. Ê LCD used in this project is 16x2. First we implement the circuit on software to assure the perfect working of this part in this project. It is connected to PORTD of microcontroller. Few set of commands are used to display a single character on LCD so some part of code is also done in this part. This LCD can be easily interfaced with any port of the microcontroller. Ê
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D"0"2Ê +Ê*Ê Next step was to implement input module. Keypad was used for this purpose. Microcontroller receives input from keypad and performs actions accordingly. 4x4 keypad used in this project. 4x4 keypad is design in such way that it gives an 8bit input to the microcontroller. Microcontroller process this input and select value accordingly.
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D"0"DÊ 6121Ê This phase of implementation was to implement serial communication module. MAX232 is an Integrated Circuit from MAXIM. It converts the RS232 voltage levels to TTL Compatible logic levels. This conversion is necessary if RS232 serial devices are to be connected with TTL compatible devices i.e. Microcontrollers or PCs (Hyper Terminals) etc. The capacitors used are of 10ȝF each. They are used in the circuit to reduce noise in the circuit. The serial connector used is DB9 Female Connector. Its pin configuration is as follows.
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