Reading data from an External MiFare 1k card

[shug94]

Hey guys, I have been struggling with this for a few days, and I am sure that you can all help.

I have a card withone target and two connections for that target. One of the connections is a MFStandard connection to a MiFare 1k. I am simply trying to read the value of the first block of this card. I have been told the key of the card, so I am pretty sure that it is correct.

Please look at my code and tell me what I am doing wrong.

/*****/

MFBlock tempMFB;
MFValue tempMFV;
byte key[] = {(byte)0xff, (byte)0xff, (byte)0xff, (byte)0xff, (byte)0xff, (byte)0xff};
MFKey.KeyA KA = new MFKey.KeyA(key);

try
{
System.err.println("a");
this.MFSConn = (MFStandardConnection)Connector.open("nfc:rf;type=mf1k;uid=31;timeout=5000", Connector.READ_WRITE, true);
System.err.println(MFSConn.toString());
System.err.println("b");
tempMFB = MFSConn.getBlock(0); //Get the first block, which should hold the UID
System.err.println("c");
tempMFV = tempMFB.readValue(KA);
System.err.println("d");
UID = tempMFV.getValue();
System.err.println("e");
append(" " + UID + "\n");
}
catch (Exception e)
{
System.err.println("Caught an exception during connection.");
System.err.println(e.toString());

}
/*****/

The output I get is:
a
1k:0:1024
b
c
Caught an exception during connection.
java.lang.NullPointerException

and so this means that it is failing during the call to readValue. Am I using the key correctly?

Thanks in advance,

Cam

[samuuh]

Hi,

You cannot use readValue method to read the content of the manufacturer block as it is not Value Block. For more information about Value Blocks see MF1 IC S50 Functional Specification, Chapter 6.6.2.1 http://www.nxp.com/acrobat_download/...on/m001052.pdf

Use read method of MFBlock instead. Structure of manufacturer block is defined in same document chapter 6.6.1

[tsavinen]

To read UID of a tag you might want to check "Read serial number of NDEF (NFC) tag" and "Reading UID from embedded Mifare tag" examples in
http://wiki.forum.nokia.com/index.ph..._Code_Examples

[mina.metias]

hey guys,...
i just had one simple question.
what are the parameters in the MFBlock.read(key,byte[],ar2,ar3,ar4);
what are arg3,arg3,arg4 stand for.

is the and API,so i can read and understand for this!?

thank you in advance

[a_whitecloud]

download S40 nokia 6212 NFC sdk and install it ( http://www.forum.nokia.com/info/sw.n...2_NFC_SDK.html ), then you will find the API.