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[Michael Limb]

Great, thank you!

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[Michael Limb]

Great, thank you! I'll give that a shot and let you know if I have any issues.

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[Michael Limb]

Here are the attached screenshots that were supposed to be in the first post. Apologies!

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[Michael Limb]

You pay for a certain amount of credits, and from what I can see, the amount of credits you have is the amount of active users you can have at one time. For example, if you had 1000 credits, you could have 1000 different people using your app at once. (MiFare, please correct me if I'm wrong).

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[Michael Limb]

Cesar,

My solution was to use the Advanced SDK. After purchasing credits for this, I was able to get the application IDs and select the application on the card, then read the data off the application.

Hope this helps,
Michael

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[Michael Limb]

Hey there,

The issue was that I wasn't specifying the CommunicationType. Once I added that in, I was able to read the second file.

Thanks for your help!
Michael

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[Michael Limb]

Hi there,

Yes, I'm sure that the file exists. To make sure, using the selectApplication call with my array of appIds returned, I called idesFireEV1.getFileIDs(), and got the attached results back (file_ids.png). Here's a code snippet of that area:

// Grab instance of DESFire EV1 interface

                IDESFireEV1 idesFireEV1 = nfcScanEvent.getIdesFireEV1();



                // Try to connect to card.

                idesFireEV1.getReader().connect();



                // Get all application IDs on the card

                int[] appIdArray = idesFireEV1.getApplicationIDs();



                // Make sure we received at least one

                if (appIdArray.length > 0) {

                    // Select the first app id, since the TriMet cards should only have one.

                    idesFireEV1.selectApplication(appIdArray[0]);



                    // Grab file ids

                    byte[] fileIDs = idesFireEV1.getFileIDs();

                }

It is crucial that we read this second file, and the method call returns two file IDs. I also requested verified cards that they have been able to read both files on from the manufacturer, so I can confirm that there are no issues with the card's data.

Any ideas would be greatly appreciated, as this is causing our development to come to a grinding halt.

Thanks,
Michael

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[Michael Limb]

Hey there,

So I'm now able to read off the DESFire EV1 card successfully using the Advanced SDK, but I'm now having another issue. There are two file ids on the card, and I am able to read the data in first file (0) fine, but when I try to read the data from the second (1) I am getting this error when trying to use the readData(int, int, int) method:

java.lang.NullPointerException: src == null

at java.lang.System.arraycopy(Native Method)

at com.nxp.nfclib.desfire.DESFireEV1.ˊ(:6077)

at com.nxp.nfclib.desfire.DESFireEV1.ʻ(:6293)

at com.nxp.nfclib.desfire.DESFireEV1.ˊ(:5730)

at com.nxp.nfclib.desfire.DESFireEV1.readData(:3581)

at com.nxp.nfclib.desfire.DESFireEV1.readData(:3503)

...

Here's the offending code:

byte[] transactionFileData = idesFireEV1.readData(

    1,

    0,

    16

);

Any suggestions on this error?

Thanks,
Michael

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[Michael Limb]

So will the single edition be licensed? As in, there will be no free version anymore, and we will have to pay no matter what? Also, will the licensing be the same as it currently is (using credits based on user activations)?

Do you have an ETA on this? Currently, I'm planning on using the Advanced SDK for my solution just because of deadlines, but I would be open to integrating the new SDK after as a solution.

Thanks again,
Michael

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[Michael Limb]

I understand that it is "part" of the Lite SDK, but I can't use it without an Advanced license key. I have to use the

com.nxp.nfcliblite.NxpNfcLibLite

class to register the activity (with the registerActivity(Activity) method here. After registering my Activity, I use the filterIntent method (also documented here). I can't use the NxpNfcLib class, because I don't have a license key to use with the registerActivity method. The callback for the DESFire EV1 card (onDESFireCardDetected) returns a com.nxp.nfcliblite.cards.IDESFireEV1 object, which does not contain a getApplications or selectApplication method. So I guess my question still stands: Do I need to use the Advanced portion of the SDK to access these methods?

Also, as I asked before, how does the licensing work around the Advanced SDK? How are licenses tracked? When I clear data, will it use another credit?

Thanks again, and sorry for the confusion,
Michael

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[Michael Limb]

Also, another question about the Advanced SDK. How does it track app activations? For example, if I was to clear data on an app, would it use another activation? Is there a system in place for some sort of developer mode so that credits do not get used up?

Thanks,
Michael

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[Michael Limb]

Hey there,

Thanks for the feedback! It looks like I don't have access to selectApplication or getApplications. Is this only available in the Advanced SDK? I'm using the LITE version.

Thanks,
Michael

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[Michael Limb]

Hey there,

Thanks for the response! As I specified above, I was under the assumption that the cards did not require authentication to read, after reading the specification for the card as designed. I have colleagues that have had similar results of being able to read the card without having to authenticate first. Are you saying that this is not a feature that is present in the DESFire EV1 cards?

Also, I have tried to use the authenticate method previously, but got this error:

02-22 09:06:51.121 21544-21544/com.example.nfcreader E/MainActivity: Error reading from DESFire card.

      com.nxp.nfclib.exceptions.DESFireException: invalidResponse: Authentication Error

              at com.nxp.nfclib.desfire.DESFireEV1.ˎ(:5500)

              at com.nxp.nfclib.desfire.DESFireEV1.ˎ(:1405)

              at com.nxp.nfclib.desfire.DESFireEV1.authenticate(:1055)

              at com.nxp.nfclib.desfire.ˊ.authenticate(:48)

              at com.nxp.nfcliblite.cards.DESFireEV1.authenticate(:471)

              at com.example.nfcreader.MainActivity$2.onDESFireCardDetected(MainActivity.java:129)

              at com.nxp.nfcliblite.NxpNfcLibLite.ˊ(:573)

              at com.nxp.nfcliblite.NxpNfcLibLite.filterIntent(:369)

              at com.example.nfcreader.MainActivity.onNewIntent(MainActivity.java:73)

              at android.app.Instrumentation.callActivityOnNewIntent(Instrumentation.java:1212)

              at android.app.Instrumentation.callActivityOnNewIntent(Instrumentation.java:1224)

              at android.app.ActivityThread.deliverNewIntents(ActivityThread.java:2545)

              at android.app.ActivityThread.performNewIntents(ActivityThread.java:2557)

              at android.app.ActivityThread.handleNewIntent(ActivityThread.java:2566)

              at android.app.ActivityThread.-wrap12(ActivityThread.java)

              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1416)

              at android.os.Handler.dispatchMessage(Handler.java:102)

              at android.os.Looper.loop(Looper.java:148)

              at android.app.ActivityThread.main(ActivityThread.java:5417)

              at java.lang.reflect.Method.invoke(Native Method)

              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)

              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

The line the stack trace is pointing to is here:

// Authenticate so we can read.

idesFireEV1.authenticate(masterKey, appId, appKey);

Unfortunately I can't include the keys for obvious reasons, but I've converted them from Strings (in hex format) into byte arrays for passing.

I'd love to know a little more about the reason I'm getting these errors if possible, since neither of them are very verbose.

Thanks,
Michael

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