Attendance system based on RFID
SPECIFICATIONS
Title of the project : RFID based attendance system
Domain : Embedded Systems Design
Software : Assembler, Proload
Microcontroller : 89S52 CISC Micro Controller
Power Supply : +5V, 500mA Regulated Power Supply
Display : a) LCD, HD44780 16-character, 2-line (16X2)
b) LED 5mm
Crystal : 11.0592MHz
Communication : RS232
Sensors : RFID reader
Time keeping : Real Time Clock
Applications : colleges, offices, companies etc
ABSTRACT
RFID is an acronym for radio frequency identification. RFID is a member of automatic identification and data capture (AIDC) technologies and is fast and reliable means of identifying just about any material object. This project can be applied in real time applications as recording attendance etc.
Primarily, the two main components involved in a Radio Frequency Identification system are the Transponder (tags that are attached to the object) and the Interrogator (RFID reader).Communication between the RFID reader and tags occurs wirelessly and generally doesn’t require a line of sight between the devices. RFID tags are categorized as either active or passive. Active RFID tags are powered by an internal battery and aretypically read/write, i.e., tag data can be rewritten and/or modified. An active tag's memory size varies according to application requirements; some systems operate with up to 1MB of memory. Passive RFID tags operate without a separate external power source and obtain operating power generated from the reader. This project uses passive tags. The reader has three main functions: energizing, demodulating and decoding. The antennaemits radio signals to activate the tag and to read and write data to it.
In this project, the RFID module reader typically contains a module (transmitter and receiver), a control unit and a coupling element (antenna). This module is interfaced with the microcontroller and when the card is brought near to the RFID module it reads the data in the card and displays it on the LCD module.
The data in the card is matched with the data in the program memory. If the match is found the card holder name is displayed. The date and time are recorded in the memory and simultaneously displayed on LCD display. If the data is not matched then then it simply displays as “no match found”.
In this project we are using RTC to get current time. The RTC is provided with battery backup. To set the current time two switches are provided one for entering and other for incrementing. A provision for checking the data is also provided. A data mismatch is generates audio visual indication. The buzzer also provides a beep for successful card match.
The significant advantage of all types of RFID systems is on non contact, non line of sight nature of the technology. Tags can be read through a variety of substances such as snow, fog, ice, paint, crusted grime and other visually and environmentally challenging environments. The barcodes or other optically read technologies would be useless . hence this project is very much useful and implemented in real timeapplications for recording attendance.
This project uses regulated 5v, 500mA power supply. 7805, a three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac output of secondary of 230/12v step down transformer. The RFID module requires a separate +5v
Power supply.
BLOCK DIAGRAM
Tidak ada komentar:
Posting Komentar