Read memory

[Mythar]

Hello, is it possible to read the memory of a card directly (not as a NDEF tag)? The point of reading the data directly, is to code the memory to avoid the annoying android NDEF tag dialog popup. The app: NFC Tools, has this options, and I need it :)

[Harry-Chen]

Sure. You may refer to the documentation of your tag and use proper commands (e.g. APDU in ISO14443) to read the memory.

[Mythar]

Can you give me an example please? :)

[jiegec]

You can refer to https://www.nxp.com/docs/en/application-note/AN1305.pdf for reading MIFARE Classic Tags.

[Mythar]

I need to read Mifare Ultralight EV1, iso14443A

[jiegec]

Possibly useful links for you:

https://www.nxp.com.cn/docs/en/application-note/AN11340.pdf

https://www.nxp.com.cn/docs/en/data-sheet/MF3ICDX21_41_81_SDS.pdf

https://stackoverflow.com/questions/42542610/authenticating-ultralight-ev1-with-pc-sc-reader

[Mythar]

Thx, trying to make sense of it all...

[Mythar]

Ok, got this far: FF B0 00 04 30 according to: https://tech.springcard.com/2014/reading-and-writing-data-in-a-mifare-ultralight-card-with-a-proxnroll/ Using the springcard encoder in my card printer, it reads the card as it should, in SHARED mode, not in DIRECT mode.

Test code:

NFCTag tag = await FlutterNfcKit.poll(
          timeout: Duration(seconds: 10),
          androidPlatformSound: false,
          androidCheckNDEF: widget.androidCheckNDEF,
          iosAlertMessage: widget.text
      );

      if (tag.type == NFCTagType.mifare_ultralight) {
        var result = await FlutterNfcKit.transceive("FFB0000430", timeout: Duration(seconds: 10)); // timeout is still Android-only, persist until next change
        print('READ:');
        print(result);
      }

I get this error:

E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): Transceive Error: FFB0000430 E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): android.nfc.TagLostException: Tag was lost. E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at android.nfc.TransceiveResult.getResponseOrThrow(TransceiveResult.java:48) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at android.nfc.tech.BasicTagTechnology.transceive(BasicTagTechnology.java:154) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at android.nfc.tech.NfcA.transceive(NfcA.java:123) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at java.lang.reflect.Method.invoke(Native Method) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin$Companion.transceive(FlutterNfcKitPlugin.kt:48) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin$Companion.access$transceive(FlutterNfcKitPlugin.kt:32) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin.handleMethodCall(FlutterNfcKitPlugin.kt:131) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin.onMethodCall(FlutterNfcKitPlugin.kt:58) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:818) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at android.os.MessageQueue.nativePollOnce(Native Method) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at android.os.MessageQueue.next(MessageQueue.java:335) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at android.os.Looper.loop(Looper.java:206) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at android.app.ActivityThread.main(ActivityThread.java:8512) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at java.lang.reflect.Method.invoke(Native Method) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:602) E/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1130) W/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): Exception occurred when using MethodChannel.Result: java.lang.IllegalStateException: Reply already submitted W/im.nfc.flutter_nfc_kit.FlutterNfcKitPlugin(13567): Will ignore all following usage of object: io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler$1@ece65a9

[Mythar]

No matter what i send in transceive, i keep getting a Transceive Error. Your code calls android.nfc.tech.NfcA.transceive, would it matter if changed to android.nfc.tech.MifareUltralight.transceive ? I know MifareUltralight tags are NfcA, so not sure if it would make a difference ?

[jiegec]

No matter what i send in transceive, i keep getting a Transceive Error. Your code calls android.nfc.tech.NfcA.transceive, would it matter if changed to android.nfc.tech.MifareUltralight.transceive ? I know MifareUltralight tags are NfcA, so not sure if it would make a difference ?

That's probably where the problem lies. You can try to call MifareUltralight instead in your application and see if it works.

[Harry-Chen]

See https://github.com/nfcim/flutter_nfc_kit/blob/a7e277ae4cb6ae8b492ad693607d5acb55d3245c/android/src/main/kotlin/im/nfc/flutter_nfc_kit/FlutterNfcKitPlugin.kt#L319-L376

You may add tagTechnology = MifareUltralight.get(tag) after line 336 and see if it works.

[Mythar]

Tried it - not working.

However I came across this in: https://developer.android.com/reference/android/nfc/tech/MifareUltralight

Implementation of this class on a Android NFC device is optional. If it is not implemented, then MifareUltralight will never be enumerated in Tag#getTechList. If it is enumerated, then all MifareUltralight I/O operations will be supported. In either case, NfcA will also be enumerated on the tag, because all MIFARE Ultralight tags are also NfcA tags.

Not sure what they mean by "implemented" ?

[jiegec]

It depends on your Android phone. If it is implemented by the card reader chip in your phone, it can be implemented in software.

[Mythar]

I know my phone can read the card, using the NFC Tools app (Tested on both Android phone and iPhone)

The exception thrown is: InvocationTargetException

I tested on my iPhone also, but get same-ish error:

[CoreNFC] 00000002 83cc41b0 -[NFCTagReaderSession transceive:tagUpdate:error:]:789 Error Domain=NFCError Code=100 "Tag connection lost" UserInfo={NSLocalizedDescription=Tag connection lost}

[Mythar]

I did some more digging and found that I cant read the whole mem in one go. Using:

var mem1 = await FlutterNfcKit.transceive("3004", timeout: Duration(seconds: 10)); // timeout is still Android-only, persist until next change
var mem2 = await FlutterNfcKit.transceive("3008", timeout: Duration(seconds: 10)); // timeout is still Android-only, persist until next change
var mem3 = await FlutterNfcKit.transceive("300C", timeout: Duration(seconds: 10)); // timeout is still Android-only, persist until next change

Works!

[Harry-Chen]

I know my phone can read the card, using the NFC Tools app (Tested on both Android phone and iPhone)

The exception thrown is: InvocationTargetException

I tested on my iPhone also, but get same-ish error:

[CoreNFC] 00000002 83cc41b0 -[NFCTagReaderSession transceive:tagUpdate:error:]:789 Error Domain=NFCError Code=100 "Tag connection lost" UserInfo={NSLocalizedDescription=Tag connection lost}

InvocationTargetException probably means your MifareUltralight class has no transceive method.