Handling multiple devices with st25r3911b

[rabinniroula]

How would i send apdu to multiple detected devices? I believe I should use the rfalIsoDepPollAHandleActivation() function with different DID values. I couldn't find much documentation on DID other than it's used to determine which device to activate and that it's a logical address, could you explain?

[Ulysses HERNIOSUS]

Hi,

although a multi-activation exists in ISO14443-4 (Annex A) this method I have never seen being used. NFC Forum and EMVCo only ever have one tag activated at a time. Our RFAL does not support multi-activation. NFC Forum allows deselecting the active tag and activating a different one. I would propose for you to do the same - there are APIs inside rfal_isoDep.h for deselecting. Peaking into rfal_nfc.c you can find examples of usage (follow the RFAL_NFC_DEACTIVATE_SLEEP rabbit there). Or maybe you just want to use the higher rfal_nfc layer?

BR, Ulysses

[rabinniroula]

I'm not talking about activating multi activation, I'm talking about activating a certain PICC when multiple are present in the field. How would i select one from the other?