Once solve the problem I had on a previous post, let's go to another and more important one.
I have several mifare 1k cards. I wanna write a record on it and then read it. I have the midlet working properly on the simulator but when getting to the real device the writeNDEF function returns an IOException: authentication error.
I have check the mifare card with keys 00..00 A0...A5 FF..FF and D3DF... but still doesn't make it to succeed.
Which are the keys used by writeNDEF() to write the record on the card? Do the card has to be a special one? What is the structure?