one general question concerning RFID readers...

maybe there are differences between different RFID readers, but i’ve been wondering what they report if there are several RFID tags in reach. do the tags interfere → aren’t readable , or is it possible to distinguish between them and read them one after the other?

in case there are differences between readers: i mean those that have been successfully used with arduino :slight_smile:

best, kuk


Using RFID in arduino is tricky because you will recieve a serial stream of 12 bits. The way I got around this was to read the bits from the RFID and store it in a string array.

Each tag does have a unique ID and u can store the bits of the serial stream as characters. So ‘F’ for 16 will be stored as the letter F.


hmm ok. thanks.

someone wrote that not all of those received 12 bits are necessarily important to distinguish between different tags. maybe you can write a function to cut it down to one byte and save only that one byte (8 bits i mean)…

concerning my question i understand that your rfid reader is sending 12bit bytes continuously. meaning that if there are three tags in reach it will send

  • 12 bits describing tag “A”
  • 12 bits describiing tag “B”
  • 12 bits describing tag “C”

and then starting all over with tag “A” in a loop?

is that right?

hey nima,
I’m very courios to know your set up.
what reader are you using? how do you connect it to arduino?


Yes i’m curious too ! :-?