I keep my XSIID write locked, I don’t think it’s necessary, but I like having it locked anyways
I haven’t forgotten the password yet, but most of my passwords look like more confusing versions of my username, so maybe I’ve just gotten used to memorizing passwords
Not to mention, doesn’t really matter to me why you want to do it, here’s how to do it should you choose to do so:
I also highly recommend you check out the datasheet: https://www.nxp.com/docs/en/data-sheet/NT3H2111_2211.pdf
Try to understand it and double check my commands if you like. While I’m 90% sure these should work, it’s a pretty good idea to get in the habit of double checking commands you send to something inside your body
You’ll need an app such as NFC Shell, or some other method to send raw hex commands (Which you should always be very cautious of, here there be monsters)
The first thing you’ll do is come up with a hex password you want, any 8 digit hexadecimal code should work.
Then you can write this password to your chip, being very very careful to do so correctly, though at this point you can reset the password if you set it wrong:
The command you’ll use to set the password is:
A2E5[Password]
Once you’re sure you’ve done that correctly, I would recommend disabling the incorrect password attempt limiter, otherwise you may risk bricking your chip if you forget your password. At the same time, you’ll set whether you want to password protect both read and write, or just writing. I recommend only protecting writing to cut down on annoyance. This should be the default value anyways, but just to be safe you can set this with this command:
A2E400000000
Now you’re pretty much done, you just need to decide what portion of the chip you want password protected. I lock the whole chip, and unlock it when I want to write to it, so that’s what I’m outlining here:
Initial lock command:
A2E300000000 (Locks entire chip from the very beginning)
To unlock, you’ll have to issue:
1B[Your Password]
A2E3000000E2 (Unlocks everything up to the password config sectors, unlocking past this could mean that anyone could change your password.)
To re-lock issue:
1B[Your Password]
A2E300000000