OOB pairing via NFC

[phst36]

Hi, I want to OOB pair two equal devices (pca10040 + NFC shield) via NFC. Since its not clear which of the two devices will act as NFC initiator (active) or tag (passive), I think I need to use P2P NFC mode.

I planned using the adafruit NFC shield and the related library for this purpose, but the Infocenter does not explicitly say that P2P is supported by the library. So I assume P2P is not supported.

So i would like to know whether P2P is the only way to achieve my goal?

Further ideas where:

1. set up the passive NFC tags on each pca10040 and let these poll by the opposite NFC shield. aka "using two antennas"
2. "Custom role switching" of the PN532 (the NFC shield IC) between initiator and target .. dont think i will manage this

Feel free to correct me and giving advises, i am at the very beginning in this topic

Thanks!

[endnode]

Hi.

According to NXP PN532 the chipset indeed supports "NFC Peer to peer" communication (see chapter 7.5.5 of User manual). However I wouldn't go that way. If you will have always only two boards then simply assign ISO14443 PCD role ("reader" = active device) to one and ISO14443 PICC ("card" or "tag" if you want = passive device) to another. If you have more devices in the ecosystem then use rotating roles where each of them polls for "tags" as PCD (typically 80-90% of time) and in the rest it listens as PICC to nearby readers. Then first time they both appear in right PCD-PICC combination the transaction is processed. It has one advantage that such device will be compatible with other PICC ("tag") only devices such as bare nRF52. But indeed you might settle down to the mode explained in NXP manual because of simplicity...

Cheers!