Adafruit PN532 RFID/NFC Shield Peer to Peer communication ex

[trentjk]

I would like to read an existing card used for opening my door using the PN532 RFID/NFC Shield. The card uses the 13.56MHz frequency, and I am pretty sure it communicates with the door reader using active communication (peer to peer). Using the PN532 Library, we can read the blank card that came with the Shield, but the program does not react when I hold the existing door card near the PN532. Also, the reader on the door takes a few seconds to communicate with the card. Is it possible to use active communication with the PN532? If it is possible, I would love to see an example code.