NDEF tag emulation

1
votes

I'm trying to emulate an NDEF tag on an abstract embedded system so, I have questions about NFC technology. Why some NFC chips can't emulate NDEF tags? If my chip doesn't support a card emulation, can I hack it somehow to fake it by using APDU commands?

1
embeddednfcapdu
The question is very abstract and needs more focus and details. But one point NDEF are not Tags, it is a data format with standard implementation methods on NFC Forum standards compliant NFC Tags 1 to 5. Not all NFC chips compliant to the NFC standards, thus some cannot support NDEF data format or they can using propitiatory encoding methods (Mifare Classic as an example) - Andrew
Thank you for your answer. I'm trying to emulate an NFC tag 4 by using NFC chip of my device but tech support of a chip manufacturer says that a chip isn't support this but they support ISO7816-4. I don't know how can it be. - TARRAKAN
Without the make and model of the NFC chip you are using it is impossible to answer. - Andrew
Manufacturer says this is a MH1608. And that's all... - TARRAKAN
But I have not found this chip. I think it can be an CR95HF - TARRAKAN

1 Answers

1
votes

If it is a CR95HF then a quick read of the datasheet because I've not used this particular chip before, suggest that like other chips I've seen that it is true that it does not support ISO7816-4 because it is not designed to work at that high level protocol level.

If you look at the picture it's working at the "protocol" level which is one level below ISO7816-4 which is fine, it can transmit/receive data at the NFC A/B protocol level but it is up to the Host's CPU to decode the raw frame data in to ISO7816-4 commands and data.

But this is not your problem, even at the lower protocol level it does not seem to be able to handle both sides on the communication.

I suggest you read https://stackoverflow.com/a/65659726/2373819 as it give some background to hardware capabilities, as the datasheet says it's "Operating modes supported:– Reader/Writer" then it is only an "initiator" and I see no signs that it can be a "target" and therefore it cannot emulate any Tags.

So in short that hardware is not capable of emulating any type of NFC Tag