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RFID Based Access Control System using 8051

In this project, we are going to build an RFID Based Access Control System using 8051 Micro Controller . The same system can be named like RFID based door lock or RFID based access management system. If you have been to big hospitals or companies, you might have seen how they used RFID based locks to restrict access to certain areas. In hospitals, only hospital staff with approved RFID tags can access Intensive Care Unit and such restricted areas. So let’s begin to build the system. Project Description A RFID based Door Lock or Access Control System is based on some simple concepts. We store a set of RFID card data in our system, say 3 or 10 RFID card data. When the person with the right RFID card (compatible to data preloaded in our program/system) come and swipes his RFID tag, access will be granted. When the person with the wrong RFID card (whose data is not loaded in our system) swipes his RFID tag, access will be denied. I hope you understand the system concept of RFID based

Learn to Build Real Time Clock using 8051and DS1307 RTC Module

In this article, we are going to see how to interface an RTC (Real Time Clock) Module to 8051 micro controller. There are different kinds of RTC module available in the market. We are using the most common RTC module that comes with the DS1307 IC, an LCD module and AT89S52 (8051 variant) for this tutorial. AT89S52 is a typical 8051 microcontroller manufactured by Atmel. Interfacing an RTC module to 8051 microcontroller is pretty simple. You only need to make 2 connections between the RTC module and 8051. So lets get to business! A Real Time Clock module is basically a time tracking device which gives the current time and date. RTC modules that comes with DS3231 IC have the provision to set alarms. Notes On DS1307 RTC Module Here we are using an RTC module with clock chip DS1307 based on I2C protocol (Two Wire Protocol). The module provides details such us second, minute, hour, day of week, day of month, month and year including correction for leap year. It can operate eithe

Astable Multivibrator using 555 Timer IC

An astable multivibrator can be designed using different types of components, say using transistors (and associated components) alone or by using op amps (and associated components). In this article, we are designing an Astable Multivibrator using 555 Timer IC. If you are wondering what all are the practical applications of an astable multivibrator, lets begin by seeing a few. One of the most common application for an astable multivibrator is to generate time delays . Let’s say you want to turn an LED “ ON ” for 1 second and keep it “ OFF ” for 0.5 seconds, then an astable multivibrator is the best circuit you could use to build this application. Unlike the monostable multivibrator, this circuit does not require any ex­ternal trigger to change the state of the output, hence the name free-running. Before going to make the circuit, make sure your 555 IC is working. For that go through the article: How to test a 555 IC for working An astable multivibrator can be produced by adding

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