I have installed a NXP NFC-ExploreNFC in Raspberry, when I run the sample card_polling program, it can detect my JIS X 6319-4 compatible card, however, it cannot detect my Samsung Note II (NFC is enabled).
Is there any extra setup required in Raspberry?
regards
Unless your phone is in card emulation mode, the card-polling example would normally not detect the phone as a card. That is, before Android 4.4 (and on NXP PN544-based devices) card emulation is normally not enabled. Though the polling example looks as if it could potentially detect a phone's passive peer-to-peer mode (when display is on and device is unlocked) as either "Mifare" ISO 14443-3 or "FeliCa" due to the fact that those modulation and protocol activation schemes are used in peer-to-peer mode too.
For reliable communication with an Android device, I would suggest that you use either the peer-to-peer mode (P2P) example or the card emulation example.
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Thanks for reading this question. I wish you have a good day.
I'm currently developing a NFC host app that generate a NFC with data I want to transfer. But I'm stuck with details about NFC modes in Samsung devices.
As you know, Samsung devices have two modes in NFC, standard mode and card mode. I thought that standard mode provides basic NFC functionalities such as generating NFC and reading NFC, and card mode is used for Samsung pay. But Some posts says that card mode is actually card emulating mode. I wonder if this "card" emulating mode has anything to do with host "card" emulation or it's just Samsung pay "card".
Long story shorts,
Which NFC mode do I have to use for HCE in Samsung device?
If I have to use card mode for HCE, can I check if NFC card mode is on?
(NfcAdapter.isEnabled() checks if the standard mode NFC is on and card mode is considered NFC off with this method)
My Samsung Device does not have 2 separate NFC modes but does have 2 different NFC capabilities - Emulation a Card or Reading/Writing to a Card. But these capabilities are not mutually exclusive they are enabled together.
It does have 2 locations where Card Emulation can happen, the first being in the NFC's Chip Secure Element (an independent CPU) or on the Host CPU (Hence the term Host Card Emulation).
All card emulation is about emulation of Type 4 NFC vards (Credit cards and similar cards)
Type 4 Nfc cards have an "Application Identifier" number or AID that identifies the format to the card.
Normally the Secure Element handles the AID's first that it has been configure to process before passing them on to the Host CPU. Normally the order of routing of AID's is seamless with Secure Element first, then Host CPU but Samsung does offer settings to change this order.
But
NfcAdapter.isEnabled() says
If this method returns false, the NFC hardware is guaranteed not to generate or respond to any NFC communication over its NFC radio.
My understanding is the UI setting that influences this status is basically a hardware power switch for the NFC chip, if this returns false the chip is turned off and won't do any NFC (Secure Emulation, Host Emulation or reading/writing)
So I would check NfcAdapter.isEnabled() before starting your HCE service.
I am working on an app that will be deployed on a NFC enabled device. I am trying to enable authentication using NFC, so that a user can scan another NFC device such as phone to authenticate.
I went through the NFC documentation that Android has at http://developer.android.com/guide/topics/connectivity/nfc/nfc.html
I am not able to get my use case working.
Here is what I am trying to do:
Deploy app in Device A.
app on Device A will only try to scan for NFC when app is in foreground and is in Login Activity.
User can bring in Device B/NFC tag near Device A, Login Activity will authenticate the user.
I hope this is possible using NFC in Android. My search leads me to example that launches app when NFC is detected but that is not what i am after.
If you want to communicate beween two Android devices by using one as an emulated tag and the other as reader/writer (as opposed to transfering NDEF messages between two devices using Android Beam, which is based on NFC peer-to-peer mode), you could Android HCE (one one device) in combination with reader/writer mode (on the other device).
However, building a solution like this has some limitations. Regarding the emulating side, you have the following limitations and requirements:
Android HCE requires the emulating device to run Android 4.4 or later.
The emulating device needs to support host-based card emulation. Not all Android 4.4+ devices that have NFC also support HCE. For instance, all (most?) devices that contain NXP's PN544 NFC controller do not curently support HCE.
You can only emulate ISO/IEC 7816-4 appliction structures on top of ISO/IEC 14443-4. In case you want to emulate an NFC tag with NDEF data, this would be equivalent to an NFC Forum Type 4 tag. But you are, of course, not limited to emulating NDEF-style NFC tags.
However, an NFC tag (or rather a smartcard application) that is emulated like this imposes some requirements/limitations on the reader side as well:
Android's HCE capabilities run in parallel with its peer-to-peer mode capablities (regardless of whether the device has support for Android Beam enabled or not). As a consequence, other Android devices will detect Android HCE devices as peer-to-peer devices and, by default, communicate with them in peer-to-peer mode. Therefore, other Android devices will normally be unable to access an Android HCE emulated smartcard application.
Only starting with Android 4.4, you can disable peer-to-peer mode discovery by using the reader mode API. So you need Android 4.4+ on the reader side in order to access the emulated NFC tag.
This also prevents automatically starting an app on the second device upon discovery of the first device, so you can only use an Android HCE emulated smartcard application in combination with an activity that already runs in the foreground on the reading device.
I am trying to develop an Android application for a hospital. In this system there is a need to get the patient information stored in the database in the android phone into the desktop computer using NFC technology. Is there anyway where I could use a NFC USB Reading device (ACR122U NFC Smart Card Reader RFID Writer 5 Mifare USB) to transfer the data from the mobile phone to my desktop computer?
The real scenario for this would be, in a hospital when a person wants to take some test results he will reach to the counter and place the mobile device on the NFC reader device installed at the counter when this is done all the details about the patient should be transferred to the desktop machine at the counter.
I don't want to transfer a lot of information if there is any way in which I could transfer the patient id stored in the mobile database into the desktop using NFC that would be enough.
Depending on what NFC devices you want to use in combination with the ACR122U NFC reader you multiple options:
If you only need to exchange a single message (data packet) in a single direction, you could use peer-to-peer mode. However, the peer-to-peer protocol stack is relatively complex (in comparison to the other alternatives). Moreover, Android's built in Beam functionality will request user confirmation (Beam UI) for every message transfer.
If you only need to support Android devices with Android 4.4 or later (and even then not all Android NFC devices are supported, see this), you could use the ACR122U in reader/writer mode. In reader/writer mode, the ACR122U can communicate with contactless smartcards. See the reader's manual on how to access such ISO/IEC 14443-4 contactless smartcards. On the Android side, you would use the host-based card emulation (HCE) mode. See the Android documentation on how that works on Android 4.4 and later.
In my opinion the best option would be to use the ACR122U in card emulation mode. In card emulation mode the ACR122U can be used to emulate a tag/contactless smartcard that can be detected by an Android device just like any other NFC tag/contactless smartcard. You can find examples, for instance, with libnfc. Also see this answer on how to bring the ACR122U into card emulation mode. This option can be used across all Android versions (and on BlackBerry and with some additional effort to some extent even on Windows Phone). With this scenario, the phone would take the reader (interrogator) part in the communication and the ACR122U (and the connected PC) would be the card (controlled component). Using techniques like inverse reader mode you could reverse that relationship.
You could use the host based card emulation for exchanging the data: http://developer.android.com/guide/topics/connectivity/nfc/hce.html
Or alternatively the p2p communication:
http://developer.android.com/guide/topics/connectivity/nfc/nfc.html#p2p
I buy ACR122U SDK that has a acr122 reader,cd and cards and I try to test it. the reader detect the cards by changing its LED light from red to green but when I take my phone (NFC is turned on) near the reader,there is nothing happen.
How do I make the reader detect my phone? I have to install java card applet into my phone for letting my phone act as a contactless card?
Using the ACR122U NFC reader you have three options:
ACR122U in peer-to-peer mode: In peer-to-peer mode, you can communicate with an Android device using Android's built in Beam functionality. On the reader side you would need to implement the SNEP service (and the underlying LLCP + NFCIP-1 protocol stack). You can find examples, for instance, with ISMB-SNEP, NFC Tools and nfcpy.
ACR122U in card emulation mode: In card emulation mode the ACR122U can be used to emulate a tag/contactless smartcard that can be detected by an Android device just like any other NFC tag/contactless smartcard. You can find examples, for instance, with libnfc.
ACR122U in reader/writer mode: In reader/writer mode, the ACR122U can communicate with contactless smartcards. This goes into the direction of what takumar already posted in his answer. While you were stuck with the requirement of a secure element (which is typically difficult due to lack of access or even lack of an SE), with recent Android versions (specifically CyanogenMod 9.1+ or Android 4.4+), you have the option to use host card emulation (HCE) mode. See the Android documentation for how that works on Android 4.4 and later.
Your phone must be enabled for card emulation, not all are. Furthermore, you need to figure out where card emulation is routed to. This can be the SIM or some embedded secure element. Once that is done, you can think of deploying the application onto a test SIM (it is very unlikely that you'll ever get the keys to the embedded secure element). Working with an AOSP build of Android (for instance on the Nexus 5) helps because you can set the route. Test SIMs with test keys can be bought online I believe. Once you have one, you can use GPShell to install the application. Good luck.
I have my own Android app (App A) which reads and writes NFC tags and ISO-14443 Type A tags. It works well on many Android devices.
I want to give the role of ISO-14443 tag to my Nexus5, so I implemented my own HCE (Host Card Emulation) application (App B) on my Nexus5. When I touch the Nexus5 on an external NFC reader (which uses ISO 14443), it works perfectly.
However, when I touch the Nexus5 (App B) on a Nexus7 (running App A), p2p (Android beam) data exchanging sequences start.
Even after I turn off Android beam functions on both devices, nothing changes. The Nexus7 doesn't display the 'Touched to Beam' screen, but the p2p detect sound plays.
LogCat shows that Nexus7 tries to establish an LLCP connection.
I want that Nexus7 to focus on detecting the ISO-14443 HCE of Nexus5, not Android beam.
How do I change the NFC detection priority to give preference to ISO-14443 over Android beam?
The solution is only available on Android 4.4 Kitkat (which is available for the Nexus 7). You need to enable so-called "reader mode", which is designed to handle this particular situation, using enableReaderMode().
In this mode the NFC controller will only act as an NFC tag reader/writer, thus disabling any peer-to-peer (Android Beam) and card-emulation modes of the NFC adapter on this device. [...] For interacting with tags that are emulated on another Android device using Android's host-based card-emulation, the recommended flags are FLAG_READER_NFC_A and FLAG_READER_SKIP_NDEF_CHECK.