Get card ID number using UID from NFC card reader

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How do I get the card id (as printed on physical card)
using the returned UID of the NFC card reader?

The NFC card reader device is ACR122u.

I'm fairly new to NFC and memories and stuff like that, so please bear with me.

I'm using a library that can get the card UID, but I don't know what to do with this information.

Here is the library I used: https://github.com/h4kbas/nfc-reader

And here is the device spec: https://www.acs.com.hk/en/products/3/acr122u-usb-nfc-reader/

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The answer really depends on the card make and model, a lot of NFC tags don't have anything printed on them, so as you don't say what the card make and model it is difficult to answer. – Andrew
Oh sorry, my bad. Edited it with the link to device spec – JayzeeNSI
Not the reader device spec's, that I knew that from the question already. I'm after the make and model of the physical card you are trying to read. The NFC specifications don't specify anything about printing anything on the physical card, therefore who ever manufacturer the physical card decided to add something. Without knowing who manufactured the card it's impossible to answer. – Andrew
I actually don't know. What I know is, the sample card can be for credit or debit, and has 16 digits numbers for its card id, and also the card nfc tag contains it. I searched around and reading a block from it requires something about passing hex memories, and some authentication, which I don't know how to do right now (I'm currently researching about it) – JayzeeNSI

1 Answers

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If the card is a contactless credit or debit card then there is no relation between the UID and any number printed on the card.

The UID is only designed as a simple method to help the hardware differentiate between cards when more than one is in range, it is not secure and should never be assigned any meaning.

The number printed on the is probably related to the account detail of the contactless credit or debit card, these are stored on the card in the memory of the card and exposed in a specific way.

Contactless credit and debit cards are Type 4 NFC cards, so you start reading the data they contain by selecting the Application ID (AID) then you continue by issuing AID specific commands to get the data you want from the card like the account number.

Some details on the various AID used by contactless credit and debit cards at https://en.wikipedia.org/wiki/EMV