st25r3911b VHBR IS0 14443A

memo · ‎2025-05-21

st25r3911b in 14443A mode

TX: BITRATE_848

RX: BITRATE_1695

tx is successful，when receive , switch B mode , but fail :CRC error ,soft framing error and hard framing error

how can I solve this problem or Which registers still need to be modified?

Ulysses HERNIOSUS · ‎2025-05-21

Hi,

ST25R3911B supports only VHBR for ISO14443B. Although modulation scheme of A VHBR and B VHBR are the same, however the frame format is different (A VHBR having parity bits and CRC_A, where as B VHBR having start and stop bits and CRC_B).

I think you will not be able to succeed this way. Only if you would dive into transparent mode and let MCU do everything.

BR, Ulysses

View solution in original post

Ulysses HERNIOSUS · ‎2025-05-21

Hi,

ST25R3911B supports only VHBR for ISO14443B. Although modulation scheme of A VHBR and B VHBR are the same, however the frame format is different (A VHBR having parity bits and CRC_A, where as B VHBR having start and stop bits and CRC_B).

I think you will not be able to succeed this way. Only if you would dive into transparent mode and let MCU do everything.

BR, Ulysses

memo · ‎2025-05-22

I see,Thank you.

Ulysses HERNIOSUS · ‎2025-05-22

Hi,

to clarify this: VHBR is possible in B only. Tx in fc/8, fc/4, fc/2. Rx in fc/8 and fc/4. DS11793 rev7 is incorrect in this aspect.

BR, Ulysses