IE ASSIGNMENT

                 Engineering Research Paper Summary Project                                                                     

                                                   

PRESENTED BY

RUBY SHAH

ROLL.NO.119

PGDIE42

RFID Based Attendance System

                                   INTRODUCTION

Traditionally the attendance at an establishment is usually done in abook register. It is time consuming. It is very difficult to verify theattendance over long periods. This method is very time consuming andvery difficult to verify the attendance over a week or above. Keepingattendance registers is space consuming. Here chances of doingmalpractice in marking attendance are high.RFID based attendance system uses RFID tags for each person. Aperson marks the attendance by swiping the tag near RFID reader module.The attendance is temporarily saved in the EEPROM. At any time thecircuit can be connected to a computer and the attendance is moved fromEEPROM to a text file in computer. It has following advantages. (1)Simplicity and reliability, (2) Saving attendance in a computer allows easyverification and longer record keeping.It works on radio frequency transmitters and receivers. Each personis given a RF ID card which is having a unique code. When it is swiped ona RF ID card reader, it reads the code and is stored. The attendance istemporarily saved in the EEPROM. At any time the circuit can beconnected to a computer and the attendance is moved from EEPROM to atext file in computer. The advantage of this system is simplicity andreliability. Saving attendance in a computer allows easy verification andlonger record keeping.

Block Diagram

EXPLANATION : RFID READER 

The DT125R series RFID Proximity OEM Reader Module has a built-in antenna in minimized form factor. It is designed to work on the industrystandard carrier frequency of 125 kHz. This LF reader module with aninternal or an external antenna facilitates

communication with Read-Only ransponders type UNIQUE or TK5530 via the air interface. The tag datais sent to the host systems via the wired communication interface with aprotocol selected from the module pinout. The LF DT125R module is bestsuited for applications in Access Control, Time and Attendance, AssetManagement,Handheld Readers, Immobilizers, and other RFID enabledapplications.The AUTOMATIC DATA COLLECTION Technology usedin th RFID reader.

Features

•Selectable UART or Wigand26.

•Plug-and-Play, needs +5V to become a reader.

•No repeat reads.

•LED/Beeper indicates tag reading operation.

•Excellent read performance without an external circuit.

•Compact size and cost-effective very efficient module for portable readers.

                               

 Data Transmission is in ASCII Standard. Data read from the tag isManchester encoded. The Manchester encoded data is decoded to ASCIIstandard. Decoded data is sent to the UART serial interface for wiredcommunication with the host systems. ASCII data format is shown below:

Power supply

Almost all electronic devices used in electronic circuits need a dcsource of power supply to operate .The source of dc power is used toestablish the dc operating points for the passive and active electronicdevices incorporated in the system. The combination of a transformer, arectifier, and a filter constitutes an ordinary dc supply, also called anunregulated power supply. For many applications in electronicsunregulated power supply is not good because of the following reasons.

•Poor regulation.

•Variations in the ac supply main.

•Variations in temperature.

                                CIRCUIT DIAGRAM

WORKING

Microcontroller reads time from real time chip DS12887. Whenever a RFID tagis brought near RFID module, it sends the card number in ASCII fomat to themicrocontroller. The microcontroller compares this number with those numbers in theEEPROM. If match is found, it first check whether it is a master card, then it displaysmenu for master card. If not, it displays the ID number and then sends the time and datedetails along with ID number to EEPROM for marking daily attendance. If no matchesfound, the microcontroller displays ‘Card Not Programmed’ in LCD.Master card menu consists of set time, add, edit, delete, transfer. The variousoptions are selected using the keypad keys- up, down, enter, cancel. Keypad encoder converts the key pressed into corresponding hex file. The output from RFID is given asthe serial input. The card ID number is 8 bytes long and two extra bytes serve as startand stop bits.Set time: It is used to edit the time of RTC. The time is entered using the keypad.Add: It is used to add a new tag and store the new tag number and ID number toEEPROM.Edit: It is used to edit the card ID number. The new ID number is entered throughkeypad.Delete: It is used to delete a card from record.Transfer: This option is used to transfer the marked attendance stored in EEPROM tothe computer.MAX232 is used to convert the TTL voltage to RS232 compatible voltage. Realtime clock is used to provide the date, month, and year details for marking theattendance

PROGRAM FLOW CHART

                                   FABRICATION OF PCB

Making a Printed Circuit Board is the first step towards building electronicequipment by any electronic industry. We should keep in mind that qualityof soldering affects the quality of the output. The procedure for fabricatingthe PCB for setting up the circuit of any multipurpose project is describedbelow.PCB Making:The making of PCB is as much as art on a technique particularly so whenthey are to fabricated in very small numbers. There are several ways of drawing PCB patterns and making the final boards.The making of PCB essentially involves two steps:1. Preparing PCB drawing2. Fabricating PCB from the drawingThe traditional method of drawing with complete placement of parts,taking a photographic negative of the drawing, developing the image of thenegative formed on photo sensitized copper plate and dissolving the excesscopper by etching is a standard practice being followed by large scaleoperations. However for small-scale operations, where large numbers of copies are not required, the cost saving method presented here may beadopted.PCB Drawing:Making of PCB drawing involves placement of components, locatingholes, optimum area each component should occupy shape and size of padsfor the components, track size and spacing and prevention of overcrowdingof components at a particular area. With these details the sketch of thePCB is made. For anchoring leads of component 1mm diameter holes andfor fixing PCB holding screws to the 3mm holes diameter can be made.Following these hints, a sketch of PCB is made.

 The fabrication of the PCB starts by transferring the PCB drawing onto acopper clad sheet. For a small number of PCB, a direct photographictransfer of the PCB drawing from a negative image of the drawing to aphoto sensitized copper clad sheet is carried out. The copper from theunexposed area is later etched away. For large quantity production, screenprinting method is used to transfer the PCB drawing image to the copper clad sheet. For etching the copper clad sheet 20-30grms of ferric chloride75ml of water heated to about 60degree Celsius may be used . The copper clad sheet is placed in the solution with its copper side upwards in a plastictray. Stirring the solution helps in speedy etching. The dissolution of unwanted copper would take about 45min. If etching takes longer, thesolution may be heated again and the process is repeated. The paint on thepattern can be removed by rubbing with a rag soaked in thinner, turpentineor acetone. The PCB can then be washed and dried.The pads are drilled with proper drill sizes of 0.9mm, 1mm, 3mm etc for the leads and mounting holes.

                                MERITS AND DEMERITS

Advantages

•Unauthorized attendance can be avoided.

•Easy to verify the attendances over a long period of time.

•Promiscuity of tags.

•Non-contact and non-line-of-sight.

•Space consumption can be reduced to a greater extent.

•No need to connect this system to a P.C always.

Disadvantages

•Identity theft.

•System affected by metal interference.

•Very little power available to digital portion of the IC, limited functionality.

•Lack of standards and protocols