ST25 NFC Tap app issue with Android 12

[PN.4]

We have used your ST25 NFC Tap app to read NFC tags emitted by a device with an ST25 chip. That has worked quite well up to a point when certain smartphones got their Android 12 update. Now the app displays an error.

The phones are a minority but they are delivered by leading brands like Nokia or Motorola. Android 11 works fine in all cases. Also, ST24 has no problem connecting with Android 12. Is there any known issue about this combination (chip + OS)? If yes, can it be worked around?

[Olivier L]

Hi,

What is the content of the NFC Tag? Do you read the content with a specific application or do you expect some processing done by the Android native stack? Example of native processing:

• An NDEF URI can trigger the opening of a Browser.
• An Bluetooth Handover NDEF Record can trigger a bluetooth pairing.

BTW, what do you mean with ST24? Is it the tags M24SR or M24LR?

Regards

[PN.4]

Actually, I'd try to use NFC V and some ISO commands. That's what happens later on, but I never get there since we fail to connect to the tag itself (it is detected alright). The Tap app also fails with exactly the same phones. ST24 is LR.

[Olivier L]

What is the reference of the ST25 tag which is failing with Android 12? Do you have some other tags that you could test with this phone?

"The Tap app also fails with exactly the same phones."

Did you use the ST25 NFC Tap application? What does it happen when you tap the tag with this application in the foreground? Is the tag detected properly? Is an error happening at that time or later?

[Olivier L]

To help us to progress on this issue, please use a smartphone with an Android version lower than 12.

Launch the application ST25 NFC Tap.

Go to the last tab called "Memory" and then "Dump memory to file".

Click on "Ok" button in the bottom right corner. This will dump the 8192 bytes of memory to a file called "data.bin" in /download directory of internal memory.

Retrieve the file from a PC and please send it to us.

Is there something special with this tag? Is the FTM Mailbox enabled? Did you configure it with more than one memory area? Is there some areas protected by password in read or write?

Regards

[PN.4]

• "Dump to memory file" does not work. The app displays a reading error. The same happens to M24.
• Yes, the embedded software supports FTM mailbox
• From my point of view, as the receiver, there is only one area.
• Yes, there are areas that are protected even for reading.

Of course, all of the above operations require connection to the tag, which is not possible now as Android fails exactly at the connection attempt.

[Olivier L]

• "Dump to memory file" does not work. The app displays a reading error. The same happens to M24.

Did you do this with a smartphone running Android 11? In your first message you said that "Android 11 works fine in all cases" so I was expecting that it would work.

• From my point of view, as the receiver, there is only one area.
• Yes, there are areas that are protected even for reading.

Password protection for read access is possible but not for the first area. The first area has to be always readable, this is mandatory.

In ST25 NFC Tap application, please go to "Area Security Status" . It will show the number of areas and the Read/Write protection for each area. Can you please send us a screenshot of this screen?

May I have the exact references of the phones that you used?

Thank you

[PN.4]

Did you do this with a smartphone running Android 11? In your first message you said that "Android 11 works fine in all cases" so I was expecting that it would work.

Yes, I did it with Android 11 and even Android 6. I cannot dump the memory. By "all cases" I meant connecting to and reading the tag for all other phones. I haven't check anything else since it's connecting that fails for me.

The screenshot you've requested is attached below:

The phones that work regardless of Android version are various Samsung S21, Samsung A52, Samsung S22, Redmi 9, Huawei P20 and old P8 lite.

We cannot read the tag with Android 12 and Nokia 5.4, Motorola g60s and Moto Edge 20 Lite.

[Olivier L]

Hi,

I can see on the picture that the status of Area 1 is blank, which is not expected. Something went wrong somewhere...

Please give the size of each area.

When using the "Dump memory to file" tool, it is by default configured for the total number of bytes of the tag (8192 in your case). This will create a failure when the application will try to read the areas protected in read by password.

So please change the field "Number of bytes". Use the size of Area 1. By this way, we will see the beginning of the memory (containing the CCFile and the NDEF present in Area 1).

Do you know the size of the NDEF file present in AREA1?

Would you have the possiblity to test a tag without protected areas and also with a single area? This would help to identify where the problem comes from.

[PN.4]

Hi,

Please give the size of each area.

Values taken from the ST25 app: Area 1 - 512 bytes, Area 2 - 256, Area 3 - 1792, Area 4 - 5632.

So please change the field "Number of bytes". Use the size of Area 1.

The ST25 app is able to dump up to 768 bytes (two first areas). Area 1 is filled with zeroes. The first non-zero value appears at 516.

Do you know the size of the NDEF file present in AREA1?

No, I don't but the NDEF tab says: "Area1: NDEF message containing 0 record(s). NDEF size: 0 Bytes."

Would you have the possiblity to test a tag without protected areas and also with a single area?

No, I would not. I would have to contact the manufacturer.

[Olivier L]

I have configured a ST25DV64K with the same areas and the same protections as your tag but I'm not able to reproduce your problem: I have tried 2 phones running Android 12: A google Pixel 6 and a Realme 7 Pro.

I'm afraid that I will not be able to help more than that.

[PN.4]

OK. We are also now aware that it works with Pixel. Thank you for your support.