Reading emulated cards with St25r95 / St95hf

[Jhern.1]

Hello,

I am trying to read data from iOS/Andriod App with my reader.

Currently, my reader is based on st25r95 and it is in tag detector mode waiting for physical cards. Everthing is ok so far. Now I need to wakeup and get data from smartphone or pshysical card.

For getting data from iOs/Android App I guess I have 2 options:

• Use HCE in smartphone and read the data as a physical tag. But not sure if ST25R95 supports this or I need to meve to st95Hf, or which protocol to use, methods, etc.
• Use P2P, but I think p2p is only supported in ST95HF.

My preferred choice is to go with HCE, but not sure how to proceed.

Can you confirm this can be done with st25r95?

I think I have to use 14443A protocol, but not sure if I need an upper FW layer for handlng this.

I can not find any app in playstore to emulate tags. Can you provide any recommendation on how to test this.

Regards, Ramon.

[Brian TIDAL]

Hi Ramon,

A device in Card Emulation mode acts as a physical tag. Therefore, you can directly use the ST25R95 reader to communicate with the Emulated Card and to read its content.

Usually, Android phones emulates T4AT and/or T3T tags.

Regarding Active Peer To Peer (AP2P), this is supported by ST25R3916 device but not supported by ST25R95 nor ST95HF. Be aware that not all NFC-enabled Android phones are supporting NFC P2P anymore. With Android 10 Google has marked the APIs as deprecated (https://developer.android.com/guide/topics/connectivity/nfc/nfc#p2p). Android Beam is disappearing.

Regarding ST95HF and ST25R95: both can act as reader but also can act as an Emulated Card (this is the meaning of Card Emulation feature being supported by those devices). When acting as a reader, both ST95HF and ST25R95 can communicate with a device acting in Card Emulation mode.

In the play store, you can search for something like NFC NDEF emulation.

Feel free to provide more information about your use case.

Rgds

BT

[Jhern.1]

OK,

Thanks for answering so quick.

That´s what I thought, but I wanted it to confirm it.

I am using NDEF tag emulator in my Andriod phone. But I Can not read a simple NDEF message with my evaluation kit (NDEF type 4A).

 

When clicking "READ NDEF MESSAGE" a list of service pops up on the phone, I select the one for the emulator and nothing more happens.

Full log:

02-10-2022 12:07:18	RESET SPI
			>>> CR95HFDll_RESETSPI
			<<< 8000
02-10-2022 12:07:18	ECHO
			>>> CR95HFDll_ECHO
			<<< 5500
02-10-2022 12:07:18	RF OFF
02-10-2022 12:07:18	CR95HF CONFIGURATION : ISO14443-A protocol
			>>> CR95HFDLL_SELECT, 02000280
			<<< 0000
02-10-2022 12:07:18	ISO14443-A : CONFIG
			>>> CR95HFDLL_STCMD, 0109043A005804
			<<< 0000
02-10-2022 12:07:18	ISO14443-A : INCREASE DEMOD GAIN
			>>> CR95HFDLL_STCMD, 010904680101D3
			<<< 0000
02-10-2022 12:07:18	RF ON
02-10-2022 12:07:18	ISO14443A REQ-A
			>>> CR95HFDLL_SENDRECEIVE, 2607
			<<< 0400
02-10-2022 12:07:18	ISO14443A ANTICOL 1
			>>> CR95HFDLL_SENDRECEIVE, 932008
			<<< 08869A7C68
02-10-2022 12:07:18	ISO14443A SELECT 1
			>>> CR95HFDLL_SENDRECEIVE, 937008869A7C6828
			<<< 20FC70
02-10-2022 12:07:18	ISO14443-A RATS
			>>> CR95HFDLL_SENDRECEIVE, E04028
			<<< 05788071006F7C
02-10-2022 12:07:18	ISO14443-A PPS
			>>> CR95HFDLL_SENDRECEIVE, D0110028
			<<< D07387
02-10-2022 12:07:18	TAG DETECTED (UID = 08869A7C)
 
02-10-2022 12:07:18	NFC SEND I-Block - Select Appli
			>>> CR95HFDLL_SENDRECEIVE, 0200A4040007D27600008501010028
			<<< 8007F2019140080000
02-10-2022 12:07:18	!!! NO ANSWER DURING RF COMMUNICATION

Any guess about what is happening?

What about the emulated cards in iOS? Which type I need to use to read the NDEF?

Regards, Ramon.

[Jhern.1]

One more thing. In terms of RFAL, which would be the stack to use:

 

T4T and ISODEP?

Regards, Ramon.

[Brian TIDAL]

Hi Ramon,

an NDEF stack is provided on top of the RFAL. An NDEF read/write demo application is available in the ST25 Embedded NFC library for X-NUCLEO-NFC03A1 (ST25R95 expansion board). I would recommend to use this demo for your application as this provides all you need for NDEF read/write with the proper RFAL configuration.

Regarding your Android App, I see in the trace that the answer to NDEF Application select is incorrect (<<< 8007F2019140080000). Can you make sure the NDEF Android App is currently running in foreground? There should be no popup on the phone when it receives the NDEF Application Select APDU. Which phone (brand/model) do you use? Which NDEF App do you use?

Rgds

BT

[Jhern.1]

App: "NDEF Tag emulator"

Phone: Huawei P20 Lite

Android: 9.1.0

Yes, app is running foreground and saying "Emulating...."

PopUp arises as there are several compatible services (My guess)

NFC Service is the logo of the App NFC Tag emulator

[Brian TIDAL]

Hi,

I used to have the same popup on my personal Android phone:

go to the parameters/settings menu in Android, then NFC payement & contactless then contactless payement then Others and deselect all except NdefTagEmulator.

The popup should not appears any longer and the NDEF can be read

Rgds

BT