Dear Fellow Engineers,
I have just recieved two RC522 modules from eBay, both of them came with a card and a tag. Both of them read the cards just fine with miguelbalboa's library (https://github.com/miguelbalboa/rfid). But it does nothing when I am trying to use the tags. I have also tryied using the sainsmart library: cards ok, tags no joy.
What could possibly cause this issue?
I am working with an Arduino MEGA.
~Z
Best Answer
it happened to me recently. After a lot of searching and trial and errors, I found out that the frequency of the tags didn't match that of the reader. I am sure that the tags are not of matching frequency assuming they are OK, otherwise they might be faulty. Only these two are possible answers. Let me know what you find. :)