I want to emulate a Mifare Ultralight with a pn532 from Adafruit. I can read the tag with a majority of phones, but i have problem with samsung s6 (tag is read on average 1 time on 10).
I supposed this problem can came from two things :
First supposition, the problem came from the uid of the tag i tried to emulate, let me explain :
Tag i emulate is a 7 bytes uid, but what happened is the reader only see a 4 bytes uid (check with Nxp Tag Reader and Nfc Pro Tools), because the uid is hard-wired by pn532.
In this case, the problem can be that samsung s6 can't handle 4 bytes uid.
Second supposition :
"This usually only means that you can't access the data on MIFARE Classic tags through devices without an NXP NFC chipset. With regard to your specific devices, the Samsung Note 3 contains an NXP PN544 NFC controller and, consequently, supports MIFARE Classic. The Samsung Galaxy S6 contains a Samsung S3FWRN5P NFC controller (the Note 5 probably also contains an NFC controller from Samsung) and, consequently, they don't support (and actually completely block) MIFARE Classic"
I found that on Stack Overflow, its true that with this controller its impossible to read mifare classic tag, but do you think Samsung S3FWRN5P NFC can be the problem for reading emulate tag (mifare ultralight).
If someone else got this problem, or if you know wich of my supposition can be the good one, its will be helpful.