One of the functions for which the NFC readers of smartphones are used is to read smart cards of a few bytes that allow to store certain information in them. Many daily items use this type of chips, for example, DNI, credit cards, bus cards, identifiers, etc.
Many of these chips, for security reasons, prevent any user from accessing them with this type of readers and, if they do, prevent their writing, for example, to prevent hackers from modifying the digital passwords of the DNI or the balance of a transport card. However, there are cards available to any user that can both read and write information in them simply using a smartphone and an application designed for that purpose.
In this tutorial we will teach you to read the technical data of an NFC card and know more details of it, for example, its capacity and if you can write it or is protected against writing.
The first thing we must do for this is to fulfill 2 conditions:
- Have the NFC connections enabled on our smartphone or device.
- Download and install the free NFC TagInfo app from the Play Store .
Once we fulfill both conditions, we execute the previous application and we will see a window similar to the following one.
We must bring the smart card to the back of our device (or where you have the sensor) or wait a few moments while receiving the information passively and displays it on the device. Next we will see something similar to the following.
Here we can see a lot of data about the card that we have scanned. First we will see "TAG Information" that will show us general information about the card as the manufacturer and the identification.
In the section "NDEF Information" we can see some more internal details of the memory, for example, if it is write-protected or we can write in it, as well as its capacity.
The tab "Memory Information" will show us details about the total memory of the same in the form of blocks and capacity of each block.
The "Data" tabs show us the information of each one of the blocks of the card.
To finish, in "Access conditions" we can see the permissions on each of the blocks, for example, to know if we can write on a certain block or not.
With this we have already been able to know all the technical information of our card. This information will help us to use it to find the best use for it, for example, a capacity of a few bytes may not contain much information, but if it is larger and its capacity increases it will provide greater versatility when using it .