Which frame (function) does inform that rf card is put against pn532 or rf card is just not present?

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Which frame (function) does inform that rf card is put against pn532 or rf card is just not present?

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krolikbest
Contributor I

Hello

I would like to know which frame(function) will inform that an rf card is put against pn532 or just is not present.

The situation I have :

asking in the loop "D4 4A" (inListPassiveTarget) gives me always a response informing about last read rf card but  this card is already not present over pn532 at the moment. So in this time I should take another process but how to get information that card is not present over pn532?

Best regards,

Martin

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Kan_Li
NXP TechSupport
NXP TechSupport

Hi Martin,

Did you mean the response of inListPassiveTarget command always indicates there is one card available even this card is not present? and NbTg was not zero in that case?

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and did you use InATR command after that? Please kindly clarify.

Thanks for your patience!


Have a great day,
Kan

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krolikbest
Contributor I

Hi, yes, exactly, even if an rf-card is not over pn532 I still get number of a rf-card but probably it is to be solved. I simply check one of bytes (some after D5...) and its changing tells me to do: -read a rf-card's number -send then a frame "inRelease" - which seems to be clearing or restoring this byte in state "0", so the whole action looks like (after powering on): send wakeup (55,55,00,00) do  check_byte  if check_byte<>0 then   {    do something, ie. send to uart    reset_byte    } loop So far it works. What do you mean, good or bad way? I haven't checked yet an InATR, should I? Regards, Martin Dnia 4 września 2018 10:29 Kan_Li <admin@community.nxp.com> napisał(a): community.freescale.com NXP Community Re: Which frame (function) does inform that rf card is put against pn532 or rf card is just not present? reply from community.nxp.com Kan_Li in NFC - community.nxp.com View the full discussion Hi Martin,   Did you mean the response of inListPassiveTarget command always indicates there is one card available even this card is not present? and NbTg was not zero in that case? community.nxp.com community.nxp.com   and did you use InATR command after that? Please kindly clarify.   Thanks for your patience!     Have a great day, Kan  

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