After some investigation and try, I have figured out what's wrong for my pn532 breakout from elechouse, here's the lib fixed: https://github.com/picospuch/PN532
In my case, there're no additional lines other than the vcc, gnd, sdl, scl used.
I have a Kerv payment ring and it works in exactly the same way with NFC readers. If the door lock could read your old ring, it will be able to read the payement ring with no issues.
I was enjoying unlocking my phone with my payment ring until Google disabled the feature in Oreo, boo.
@ddprincess9
No surprise it doesn't work with Apple. They would want to sell you an iRing at three times the price, then claim that it's new groundbreaking technology invented by them, like, err, contactless charging...
If your antenna + according circuit is matched at 13.56Mhz, there are no problem but I think it will be difficult to find an antenna that match with the according circuit currently on the keyduino and you will need to change some component value to improve your reading range ;)
Here's my reply from support at the end of Febuary
"We're in the final stages of refining production of the payment-enabled NFC Ring (and associated back end systems) at the moment. We're currently aiming to begin dispatch in the next couple of months."
