What I needed was an access control system for my office.
The whole project is pretty easy to build.
I had a spare Aduino Mega and a Ethernet shield at home, so, with a few more components I have been able to build an access control system for my office. It uses NFC tags and mySql database to collect data’s into a table.
Substantially, the Arduino waits for a tag, then it will try to contact a php webpage which will manage the upload of the data into the database. To do this, it will check first for the presence of the tag into a “users” table of “known” tags. The table contains infact known users and their relative tags.
If the tag is not recognized, the Arduino won’t record the access. Otherwise, it will insert a record into the table. At the moment, timestamp, id_tag, the company branch (location), and the ip are recorded into the table.
I added also a lcd to make the things easier for the users. When the access is recorded, a green led will flash for few seconds and a buzzer will play a short tone with increasing pitch. The lcd will show a short ok message for few seconds.
If some issues occur (as lan not working, or unknown tags), a red led will flash instead, and the tone played will have a decreasing pitch. The lcd will show also a short error message for few seconds.
With a couple of buttons more, you can manage to record also the kind of operation: “is that an access or an exit?!” (but this will be developed another time).”

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