Write to NTAG216 after authentication?

Question

I check my tag using this code snippet

nfcA.connect();
byte[] authResponse = nfcA.transceive(new byte[]{
                (byte)0x1b,
                pwd[0], pwd[1], pwd[2], pwd[3]
        });
nfcA.close();

I checked the result of authResponse and it is equal to my package. After authentication, I write the contents of NDEF using the writeNdefMessage()class method Ndef, but I could not write.

This is where I found a way to authenticate a tag.

This is my approach:

• Authentication tag (using this code snippet)
• If the authentication response is equal to my packet, go on to write the NDEF message

However, I get java.io.IOExceptionwhen I call writeNdefMessage().

Answer 1

, , , , . ( !), tag.connect()/tag.close() , , . , .

Ndef, , . NDEF ( NFC Forum Type 2 ) NDEF.

NTAG216 MifareUltralight, MifareUltralight.

• :

  mfu.transceive(new byte[]{ (byte)0x1b, pwd[0], pwd[1], pwd[2], pwd[3] });
  

• (, , 4 , NDEF, TLV 0x03, 3, - ):

  mfu.write(pageNumber, data)
  

  data - , pageNumber.