Compatible Implants


I’ve had my xNT for three (I think?) years now. I’ve recently moved to an office where they’re using mifare classic tags. Could you let me know if any of the X-series tags are compatible? The whole mifare ecosystem just confuses me! I’ve attached a scan of one of the cards.

I’ve also been looking into the Connexis L1 released by Yale, anybody else looked into that? I have one of the key tags they use, will post a scan when I remember.

<?xml version="1.0" encoding="UTF-8"?> 4.23 2018-05-22 12:06:24 NXP Semiconductors MIFARE Classic EV1 (MF1S70) tag FE:44:FE:50 false NXP Semiconductors MIFARE Classic EV1 (MF1S70) Maximum NDEF storage size after format: 3356 bytes 4 kB ‣ 32 sectors of 4 blocks and 8 sectors of 16 blocks ‣ 256 blocks, with 16 bytes per block Full product name: MF1S703xX/V1 Originality check not supported MIFARE Classic compatible ISO/IEC 14443-3 (Type A) compatible ISO/IEC 14443-2 (Type A) compatible Tag description: ‣ TAG: Tech [,,] ‣ Maximum transceive length: 253 bytes ‣ Default maximum transceive time-out: 618 ms ID: FE:44:FE:50 ATQA: 0x0200 SAK: 0x18

Hey @jhlewis sorry for the delay in responding… very busy these days…

Anyway, the mifare ecosystem is very confusing yes! I don’t even want to get into it… but basically “Mifare S50” was a 1k chip that is now called “Mifare Classic” … it had 4 ID bytes which used to be called UID (unique id) but it’s only 4 bytes… so now they have lapped themselves a couple times and re-used the same IDs over and over, it’s called NUID (non-unique id)… but the S50 also had a security flaw in it’s crypto1 algorithm used to protect keys, so they re-released “mifare classic ev1” … ev1 = evolution1 … i.e. the new “classic” chip is byte for byte compatible with the original “classic” chips but they fixed their algo…

In short, the xNT uses an NTAG216 chip which looks very similar in memory structure to the older Ultralight C chip, which is not “mifare classic” compatible, and has a 7 byte UID (probably soon to be called NUID but I digress)… so on the surface it does not appear to be compatible… however… both chips use ISO14443A to communicate, and some systems don’t specifically use the memory features of the S50 classic chip, they just care about the ID… so in that case you might be able to supply the first 4 or last 4 bytes of the xNT UID to the system and it may work… or if the systems supports it, all 7 bytes.

We do have a very limited run on right now of the xM1+ which is an S50 1k emulator chip… but it comes with heavy technical risk. Read the post carefully.

Hey Amal, thanks for the info. Ordered an xM1+, never been one to worry about extended warranties.

I’ve always thought a dead chip would be a nice romantic gift if you extracted and put it in a necklace. Although some would say it’s a little creepy.


Hi everyone, just wanted to put out an FYI on the xM1+.

It’s compatible with SALTO access systems, just need to be patient when writing to the tag, as the writers they use aren’t exactly made for glass tags.

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