there is ios shenanigans you can get up to but writing NDEF to mifare classic via ios is a no-go so if you’re wanting to put ndef records on it then you can do just not with an iPhone, you can still read & interpret the same NDEF records as an NTAG tho
I’ve tried to find the (super simple I’m sure) answers for over an hour and am going in circles.
The NExT, is the LF side preprogrammed?
I believe I read the LF side is pre programmed but can be changed? Is that right? So you could use it to open locks after getting it imanted, without changing anything with a flipper, or proxmark, etc?
2 And the HF side is pre programmed. And can’t be changed. Right?
3. Would the HF side of the NExT work with this (obv the 13.56 one)? I couldn’t see on the AliExpress website what specs it had.
4 (I’m a liar!!) So if I got (and I have) both the 125 and 13.56 of this listing they’d both work with the NExT? I thought I’d asked that somewhere but can’t find it if I did.
US $11.21 5%OFF | 2500 users 125Khz 13.56Mhz RFID Proximity Access Control System Board Building Intercom module Embedded Access Control module https://a.aliexpress.com/_mLUVDyY
The better answer is, The NExT should arrive in “EM mode”
The T5577 chip can pretend to be all kinds of LF things, so you just tell it what it’s supposed to pretend to be
EM is just sort of the most basic… so that’s my assumption why it’s shipped that way with some generic EM uid
(Just a guess tho)
But yes, you can totally use it for EM stuff when it arrives in EM mode (I’m 95% sure it arrives in em mode)
Here’s an important clarification about an implant working with a system… there are 2 ways you can do it
Either the reader can “learn” the UID or serial number of a chip, typically called “enrolling” as you and enrolling that card into the system as trusted etc
You can take an existing card that a reader or system already trusts and “clone” that data onto a new chip
When your done there is no meaningful difference between the 2 and (most) readers and won’t be able to tell the difference, like making a copy of a metal key
LF chips are easy to clone since they are good at pretending to be other things
HF chips are much more of a pain to clone, since usually the UID or serial number of the chip can’t be changed, unless you get a special “magic” chip which is a sort of unauthorized knockoff chip that you can reprogram (carefully to not brick it)
That’s not to say you can’t add and remove and change things on a HF chip, think of it like a semi truck… you can change the cargo really easy… but the license plate is very hard or not possible to change
Usually people “enroll” HF chips into systems, and “clone” LF… but enrolling you need access or control or permission from the system or owners…
If your building then you ofc have this…
A gym or employer might not be willing to enroll something foreign in their system… or more likely don’t know how or what your talking about
If I’m understanding what your asking
13.56 uid :3412569078 (fixed)
AND NFC NDEF payload that will share a url link to someone’s phone to a rickroll or business card
125 uid :3456901278 (rewritable)
Buying 1x125 reader and 1x13.56 reader
The 125 reader only looks at the 125
The 13.56 reader only looks at the 13.56
So yes that would work
You could also buy 2x or 17x of either and that would also work
The same metal key can open 1 or 100 doors
The reader is the lock in this analogy
The only real difference is a reader can accept a bunch of different keys, versus a lock which only really works with 1 version of a key… you just make a bunch of copies of it
Where it gets tricky is the LF uid while it can take many forms, can only be 1 thing at a time
In a nutshell
So if your gym card has a uid of 1234567890
And your work card has a uid of 0987654321
Your implant can’t do both at the same time
@Eriequiet answered you above, I just happen to remember why your asking, Your 2FA door lock for your Bus conversion correct?
I have that same HF reader, and its “made for” Mifare Classic 1k BUT I’m pretty sure I’ve used it with DESFire EV2 and NTAG216 (NExT), you just need to use the “ADD” card to enroll it and you’re up and running.
I’ll dig out my reader tomorrow and confirm it for you (Worst case, it’ll be the day after)
If it works, then yes, the NExT will be the best key for your 2FA locking system