mfrc522: ReadAndWrite Example about diozero HOT 3 CLOSED

It seems the problem is in the method
public StatusCode mifareTransceive(byte[] sendData, boolean acceptTimeout) { // Sanity check if (sendData == null || sendData.length != 16) { return StatusCode.INVALID; }
Because in the mifareWrite he is sending this array byte[] cmdBuffer = { PiccCommand.MF_WRITE.getValue(), blockAddr }; to the sendData parameter.
Maybe replace that block with communicateWithPICC to send the MF_READ instruction?

from diozero.

Hi, thank you for your advice.
I solved this problem by commenting out

// Sanity check if (buffer == null || buffer.length != 16) { return StatusCode.INVALID; }
Due to that i'm able to change the access bits in the sector trailer.

from diozero.

Excellent, thank you. I will incorporate into the other fixes that I have been making recently.

from diozero.