[Pcmofo] has shared a well-built, well-explained example of how to implement an RFID key system for a door. We call this the right way because it is well thought out and functional. In the past we’ve ...

I just received my RC522 RFID reader and made this simple Arduino access control system that uses the reader, a buzzer for the alarm and a relay shield for the security system. The relay can be used ...

A keypad is one of the most commonly used input devices in microprocessor applications. In a standard keypad wired as an X-Y switch matrix, normally-open switches connect a row to a column when ...

[Shawn] recently overhauled his access control by fitting the doors with some RFID readers. Though the building already had electronic switches in place, unlocking the doors required mashing an aging ...

We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more› By Doug Mahoney Doug Mahoney is a writer covering home-improvement topics, ...

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