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Command "InListPassiveTarget" of the PN532 device returns only one ACK and nothing else

Question asked by Fabian Romo on Apr 28, 2018
Latest reply on May 31, 2018 by Kan_Li



I have managed to communicate with the PN532 device through a microcontroller. I get it out of the low power mode, I get the firmware version and the general status.


Now I want to read a MiFare type tag (ISO / IEC14443) and the frame I send is the following:


transmissionBuffer[0] = 0x00;
transmissionBuffer[1] = 0x00; 

transmissionBuffer[2] = 0xFF; 
transmissionBuffer[3] = 0x04; 
transmissionBuffer[4] = 0xFC; 
transmissionBuffer[5] = 0xD4; 
transmissionBuffer[6] = 0x4A ;
transmissionBuffer[7] = 0x01; 
transmissionBuffer[8] = 0x00;
transmissionBuffer[9] = 0xE1; 
transmissionBuffer[10] = 0x00;


And the frame that the PN532 answers is:


receptionBuffer[0] = 0x00;
receptionBuffer[1] = 0x00;
receptionBuffer[2] = 0xFF;
receptionBuffer[3] = 0x00;
receptionBuffer[4] = 0xFF;
receptionBuffer[5] = 0x00;


I want to indicate that I perform a procedure in the reception of data from the MCU which consists of a timer that is reset every time a byte arrives from the PN532 and when no more bytes arrive, the timer overflows and it is assumed that the frame has arrived complete.


That way in a single package I get the ACK more the answer.


To rule out that the response to the "InListPassiveTarget" command takes more time than the timer, I have tried up to 20 seconds and only the ACK arrives for that command.


For the others that I mentioned at the beginning, there is no problem.


Beforehand I appreciate any suggestions or comments.