Question

我对Android NFC协议有疑问：我有一台装有Mifare Classic的设备，尺寸为4K。我尝试使用KeyB写入块27但是我总是得到IOException：Trasceive Failed。我尝试用writeBlock（int blockIndex，byte [] bArray）方法编写。授权为True，设备已连接。相同的KeyB用于读取扇区27，并且该操作正常工作。使用相同的代码（使用KeyA），我可以在扇区1中编写。

在下面的代码中，我尝试写入扇区27的第一个块（块108，其中108是块的绝对索引）。

我尝试将代码放入MainThread或第二个Thread中，但没有任何改变。任何想法???

...

    MyNfc.mAdapter = NfcAdapter.getDefaultAdapter(this);
    MyNfc.mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);

    // Setup an intent filter for all MIME based dispatches
    IntentFilter ndef = new IntentFilter(NfcAdapter.ACTION_TECH_DISCOVERED);

    try {
           ndef.addDataType("*/*");
    } catch (MalformedMimeTypeException e) {
           throw new RuntimeException("fail", e);
    }

    MyNfc.mFilters = new IntentFilter[] { ndef, };


// Setup a tech list for all NfcF tags
MyNfc.mTechLists = new String[][] { new String[] { MifareClassic.class.getName() } };


……


try {                                  
Tag tagFromIntent = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
       MifareClassic mfc = MifareClassic.get(tagFromIntent);

       MyNfc.MifareID = tagFromIntent.getId();                           
MyNfc.keyB = GYMCalcoloAlg.GYMCalcoloAlgorithm(MyNfc.MifareID, MyNfc.keyB);

       mfc.connect();
       mfc.setTimeout(10000);
       boolean auth = false;

       auth = mfc.authenticateSectorWithKeyB(27,MyNfc.keyB);

       if (auth) {
              String text = "Hello, World!";
             byte[] value  = text.getBytes();
              byte[] toWrite = new byte[MifareClassic.BLOCK_SIZE];       

             for (int i=0; i<MifareClassic.BLOCK_SIZE; i++) {
                    if (i < value.length)
toWrite[i] = value[i];
                    else
toWrite[i] = 0;
             }          


              mfc.writeBlock(108, toWrite); <-- THIS OPERATION FAILED: IOException: Transceive Failed.
}
}
catch(Exception ex){
       ex.getMessage();
}

带有KeyB的NFC Android writeBlock

0 个答案: