miguelbalboa / rfid

Arduino RFID Library for MFRC522
The Unlicense
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RFID tag shows lines "-----" instead of actual values #607

Closed maremike closed 10 months ago

maremike commented 10 months ago

I am trying to copy a RFID tag for a long time. However I have a few things that came to my attention. First of all I managed to change the UID by creating a new function in the RFID library called "SetBlockX". It worked perfectly to change the UID. Now I need to copy the last blocks of following sectors: 4,5,6,7,8,9,10,11,12,13,14 Now it would have been easy if all bytes contained a value by using the readandwrite.ino example. However all of these blocks have a following value: "3E65E4FB65B378778869------------" (key:a "3E65E4FB65B3"; ACs: "787788"; notassigned: "69"; key:b "------------") Because I cannot replicate the "-" I just replaced them with an "F". After trying it out, this is what I'm with: "------------78778869FFFFFFFFFFFF" (key:a "------------"; ACs: "787788"; notassigned: "69"; key:b "FFFFFFFFFFFF") The weird thing is that the RFID library somehow managed to make those "-", but in the key a. However when I used the same code to change the block 0, it didnt do this. I went through the code to find it out, but no results, maybe someone more experienced knows an answer. Why do they appear? Is it possible to immitate them, and how?