Did i order the right implant? (xNt vs xEM)

[amal]

@Drumpact

I have made a NFC door lock, bike lock, and computer lock using the cheap RC522s boards

Awesome!

@Drumpact

these boards should work with both chips correct?

Both? You only mention the xNT… and yes, the RS522 reader board will read the NTAG216 chip inside the xNT. The question becomes - can the antenna of the RS522 properly couple with the xNT well enough to communicate. That’s harder to answer, specifically because there is a rash of knock-off RS522 and PN532 boards out there that have shit performance. You might do well to order an xLED (HF version) to do some antenna testing.

@Drumpact

I’ve heard issues of the xEM not being able to be rewritten after being used on certain devices.

Well, it’s more of a coupling problem… read this thread.

@Drumpact

Is there a way where I might accidentally kill the chip by trying to write it with an arduino or similar device?

How do you plan on writing to the xEM? The RS522 can’t do it… the xEM is based on the ATA5577 chip which is 125khz.

@Drumpact

Also, since the UID cant be rewritten on the xNT, does that mean you cannot use it to emulate other cards and such?

Well, there is cloning and there is emulation. I call the ATA5577 an “emulator” because it can change it’s analog interface to suit the type of system you want it to talk to… and then there are chips like the xM1+ which is kind of an emulator… but it only emulates one thing - an old NXP MF1ICS50 “Mifare Classic” 1k chip… and you can change the NUID on it, so you can clone source 1k tags completely to the xM1+… but I find it difficult to call it an emulator… even though technically it is.

To answer your question though, yes the xNT uses the NTAG216 chip which is a straight up, through and through NFC Type 2 compliant ISO14443A RFID chip… it was designed to be used with NFC SmartPoster style applications.

@Drumpact

perhaps get IT to register my ID into the system

That’s your best course of action… though be warned… that process may attempt to lock out certain parts of your tag or make certain parts of the tag’s memory pages password protected in a vain attempt to produce some kind of security (since it’s related to money and payment)… so I heavily recommend using the Dangerous NFC app to protect your xNT before you attempt this.

@Drumpact

or is it only possible to clone my existing card onto an xEM

Well, if your existing card is an EM41xx or HID ProxCard II then you can clone it to an xEM, but if it is a Mifare Ultralight, Ultralight C, or NTAG2xx chip then you might have the option of asking IT to add your xNT to the system (with above mentioned caveats).

@Drumpact

which device is more future proof?

There is no clear answer to that question… but I’d lean toward the xNT since it complies with two standards (ISO14443A and NFC Type 2)… though the xEM is programmable to emulate three major chip types which are “defacto” standards in the LF landscape - EM41xx, HID ProxCard II, and Indala, which aren’t going anywhere anytime soon.

The ultimate answer though is VivoKey… that implant will actually run java card applets you can install and remove at-will.