xNT can only be read with android NFC


#1

Hey guys!
I am having trouble with my xNT as I can only read it from an android phone.
When I use my pn532 it does not even react to the xNT touching it, it worked a few months ago but I might have tinkered too much…
Does the tag need to be formatted a specific way to be read with a PN532? I formatted it using an android app a while back and I am worried it is now in a different format than the PN532 needs.
Might I just be missing the authentication key?
Or am I just doing something stupid?
I am hoping one of you guys has more of an idea about this…
(dump of memory included below)

Thank you all very much.
.
.

-Warren Willingham

Get Version: 00 04 04 02 01 00 13 03
Page 00: 04 5F DC 0F
Page 01: 12 FF 38 81
Page 02: 54 48 0F 00
Page 03: E1 12 6D 00
Page 04: 03 00 FE 00
Page 05: 00 00 00 00

Page E2 :00 00 7F BD
Page E3 :00 00 00 FF
Page E4 :00 05 00 00


#2

Hi Warren,

The likely issue with your PN532 is software or tag orientation. The format of the tag doesn’t typically matter. If you are using NFC software looking for a specific NFC record, then use the support tool to write a “blank ndef” record and see how it works.

Check out the video on this product page to learn about tag orientation; https://dangerousthings.com/shop/xled/


#3

Thank you so much! My buddy has another RFID reader I’ll let you know how it goes.
Thanks so much!


#4

Looked more into this and tried it with different pn532 readers still to no avail. had an old pn532 reader that it worked perfectly on, then it broke(set chair down on it, yay…).

I am just trying to use their ISO14443a UID reader example that comes in the library.
I know the problem is not the read range because on my old PN532 the read range was fine, Actually I was getting like half of a centimeter, they’re great. I know a decent amount of magnetic fields and what shapes they produce/what the proper orientation is to get the most out of it(enough).
The PN532 works fine with all other mifare tags. Works with classic, and a few ultralight’s that I had lying around.=

I may have accidentally formatted it to a different version or something of the sort or maybe overwrote some parts that I shouldn’t have??
Can you compare the data dump I have above to one that is working for you or can you send me a data dump of one that is working?
Or is there anything else that I should be looking for?

I am sorry to bother you with all of this, I just figured you would know best.
If I should be doing this by email just let me know.
.
Thanks so much again!

Warren Willingham


#5

Hi Warren,

There absolutely is no way to format or otherwise change the content of an NTAG216 chip that would “break” it or somehow make the UID stop being selectable/readable. That’s just not possible. The only reason NDEF records matter is that many NFC readers and software apps that claim to be compliant are not, and need to be baby stepped a bit when it comes to blanking out the ndef data.

There are, however, a number of shoddy knock off PN532 readers floating around out there that don’t work half as well as others in terms of magnetic field coupling. Even though that may look the same or look like they have the same antenna, the tuning is horrible and you really have to mess around with tag orientation to get a good read from glass tags (while reading cards and fobs may still work well enough).

I prefer to work via forum over email… our correspondence may be helpful for others :slight_smile:


#6

That’s what I needed to hear! Thank you! I knew I was asking the right person, Haha.

This is probably just a crappy PN532 and I got lucky with my first one!

I will see if someone I know has one that works,

I was getting really stressed out that I had somehow broken the tag that was in my hand.

I will message you back with any updates, and if i havent said it enough, thank you so much for helping me with this!


#7

I just tested the card on a reader that used to work for sure, it didn’t work.
Is there any app that you know of to remove the password that was placed on it by the dangerous NFC app?
Yes this is dangerous territory but i would like to try.
and second question, you mentioned that some readers would only work if you blanked out the NDEF. Could you link me to one that absolutely doesnt require that and works?
Does the PN532 on your site absolutely work?]

Thanks so much for all the help, I Would like to find a way to avoid having to cut the old tag out and put a new one in.

Warren Willingham


#8

Tried some of them that I bought from china, only 2 worked at all out of the 6.
I guess it worked on the first one I bought so I assumed it worked for all of them.
Thank you so very much for your help on this.
I had no idea it was something this simple.

THANK YOU


#9

I’m having you’re exact same issue. I’ll upload a short video documenting it to be sure. Could you provide me a link to the reader that you got that worked?


#10

Hi @warrenwillingham, sorry I didn’t get back to this thread… basically yeah, there are some PN532 boards from China that are basically knock offs and don’t work so well… they use crap parts and the tuning is bad and inconsistent, so some boards may work with the xNT, some may not. Our PN532 reader board is from a legit source and works consistently with the xNT and really well with the flexNT.

Also, the password… it is possible to set it to another value, but you cannot remove it. The factory default password is FF FF FF FF, so you could set it back to factory, but it is not possible to “remove” it… only set it back to factory default.