topic Re: MIFARE supported bitrates in NFC

MIFARE supported bitrates

piergiuseppe_tu — Mon, 20 Jul 2020 12:33:16 GMT

https://www.mifare.net/wp-content/uploads/2015/02/MIFARE-Z-Card-2017.pdf reports that Ultralight and Classic support only 106kbps communication speed, whereas, once queried by RATS they both report a TA(1)=0x77 in their ATS response (complete response: 0x06 0x75 0x77 0x81 0x02 0x80).

I'd like to know who's telling the truth and who's not.

Thank you in advance,

Re: MIFARE supported bitrates

Jonathan_Iglesias — Mon, 20 Jul 2020 16:28:01 GMT

Hi Piergiuseppe Tundo,

Hope you are doing great, please follow the documentation in our webpage and in Mifare.net as you may know this two tags are T2T which means the speed is 106kbps. you are saying the cards answer with a RATS, well this is not possible directly form the cards, since this cards are ISO 14443-3 they answer to a REQA command with ATQA, this will activate the card in ISO 14443-3 to activate a card in layer 4 of this iso ( which is the layer for smartcards like DESFire or Plus) you send a RATS and the card answers with an ATS. I assume you might be using a PC/SC reader device that usually work on layer 4, and when a type 3 tag is detected a pseudo ATS is generated to comply with the reader communication.

please follow the NXP documentation available

Mifare classic - https://www.nxp.com/docs/en/data-sheet/MF1S70YYX_V1.pdf
Mifare Ultralight Family - MIFARE Ultralight | NXP

Jonathan

Re: MIFARE supported bitrates

piergiuseppe_tu — Tue, 21 Jul 2020 09:03:48 GMT

Hi Jonathan, thank you very much for your prompt reply.

I'm using PN7462 and NFC Reader Library but I forgot to reset ATS buffer before each discovery loop, so I was actually decoding stale ATS from previously detected T4T cards.

Thank you again.