CR95HF - Detect card removal

[Ciro Donnarumma]

Posted on August 11, 2017 at 11:26

Hi,

is there a way to detect if a tag ISO14443A/B leave the field of CR95HF antenna? I need to detect the event 'card removed' without change status of the card , therefore I can't send any messages to the card.

Best regards,

Ciro

[Rene Lenerve · Accepted solution]

Posted on August 21, 2017 at 15:50

Hi

Donnarumma.Ciro

,

There is no option to directly detect that a tag as leaved the field. I think one solution could be to send the last command and check that you received the same answer (in that case the tag will keep is status). And in case of tag out of the field you will received an error code 0x87 from CR95HF.

Hope that it will help you.

Best Regards.

[Ciro Donnarumma]

Posted on October 04, 2017 at 11:44

Thank you very much for your answer.

Your solution is correct, however I solved my issue with a similar strategy that doesn't require the storing of the last sent-received messages.

I send an R(NACK) frame (0xB2) to the smartcard. So, in case of card out of field, as you say, the CR95HF send me an error code 0x87.

Best Regards,

Ciro