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A Very Compact Alarm with Card Reader and Real-Time Clock

This is an alarm for your house that rings when a movement is detected, like when the door is open or when a body walks in front of it.

This is my first project released on Hackster and every suggestion is accepted. Well, I’ve made this alarm just for fun and I hope you will like it!

How does the alarm work?
In order to see from the image to start the alarm, you must put the correct magnetic card on the RC522 Card Reader. If the card is indeed correct, the alarm will turn on automatically (green LED: on; red LED: off), but if the card isn’t correct, nothing is happening (green LED: off; red LED: on).

When the alarm is started, the HC-SR04 Ultrasonic Sensor will capture any movement in front of it.

To shut down the alarm, we will again put the correct magnetic card on RC522 Card Reader (green LED: off; red LED: on).

What if you forget to turn on the alarm before going to sleep?
We can go to sleep without activating the alarm because the Real Time Clock will activate the alarm at a certain hour.”

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