Multiple nfc uses?

Hey so i was looking at smart locks and the SHS-3320 is 13.56Mhz, PERFECT!

But if im using the nfc to unlock my door, does that mean i can’t also have my website link/whatever else i program onto it through the nxp app?

or does the nfc chip have its own identifier and that’s what my smart lock will be looking for instead of anything else stored on my chip?

Sorry, im still so new to all this!

Two things…

According to forum members, Samsung has changed the firmware in their locks and they no longer support NTAG216 chips (or probably any other types aside from 4 byte NUID Mifare “classic” chips)… but they did not change the model numbers of their locks… just the firmware… so it’s impossible to tell if the lock will work without testing. This pissed me off to the point that I posted we should build our own open source lock, which came together rather quickly actually… and now we are working on getting some DFM feedback from a couple factories… but it’s all slow going because it’s holiday season everywhere.

Not at all… because your chip has a unique serial number (UID - unique ID) and this is what the locks use… unlike metal keys and locks, you don’t keep a “keychain” of “keys” on your chip, your chip is a unique key, and the locks maintain a list of unique keys allowed entry. What you program into the user memory of your chip is totally separate from the UID and has no impact on how most access control systems work - they typically just read the UID and that’s it (totally insecure btw).

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Thanks amal! that does suck about the locks, but at least i found out before buying one of them

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I wonder if Samsung did it to prevent users from using generic NFC tags (and have them buy official cards and keychains), of another reason?

I seriously doubt they care at all about this, or they would have switched up to a much more secure tag type. I think it’s simply a PCB change which may have resulted in a change of reader chip and change of firmware… the reader chip will totally be able to read any iso14443a chip, but the firmware controlling the read, register, and authentication process is probably a minimum scope job from some loser programmer not interested in doing anything above the bare minimum… so it probably doesn’t even handle UIDs larger than 4 bytes… that’s the most likely issue to be honest… i seriously doubt it was any kind of move to actually improve security or wedge out generic tag types.