VHBR and ISO 14443-A

[DGabc.1]

The ST25R3911B datasheet indicates it supports VHBR. In the RFAL code, there is default configuration for NFC-B VHBR rates, but nothing for NFC-A (ISO 14443-A).

Are VHBR rates supported for ISO 14443-A?

[Ulysses HERNIOSUS]

Hi DGabc.1,

DS Table 26: VHBR Tx is supported only for ISO14443B mode.

BR, Ulysses

[DGabc.1]

Hi Ulysses,

Does that mean that VHBR Rx is supported only for ISO14443B mode?

The table specifies Tx, but no restriction on Rx.

Thank you

[Ulysses HERNIOSUS]

Hi,

as VHBR PICC frames are same for ISO14443A and ISO14443B mode so I think also ISO14443B mode could be used for reception but then you need to switch mode between TX and RX and also the CRC is different which you then likely would need to do in SW.

Theoretically ISO14443A HBR TX with VHBR RX should work but I have no experience with it.

So far I have experienced VHBR only with ISO14443B cards. Could you tell which ISO144443A VHBR tags you are using?

BR, Ulysses

[DGabc.1]

Hi Ulysses,

Thank you for the detailed answer. This is very helpful.

I was asking just from general capabilities point of view, without a specific tag in mind.

Best regards,

DGabc