NFC frame details understanding

[JeanFifre]

Hi there,

I'm a beginner with NFC and there is somethings I don't understand with the NDEF Messages frames. I have a the PCA10040 Development Kit.

I've seen this schematic : blog.zenika.com/.../NFC_Record_Layout.png

But I don't understand the message that I read which is the following one :

5F0B1DC118CC743A (I guess the Serial number) 9A ? 03 ? FF ? FF ? E1 ? 11 ? 7C ? 0F ? 03 (I guess TLVs for NDEF) 09 (Payload Length) 83150000003977696E (Payload)

Is there someone who can explain me the 8 bytes with question mark ? Or if I'm wrong with the other ones too ?

Thanks a lot

Best regards

[Michal]

Hi, these bytes are set according to the NFC Forum "Type 2 Tag Technical Specification" Version 1.0 (section 4). Theres is however some freedom on how to set byte0 - byte9, all the details you can find in the nRF5 SDK documentation: infocenter.nordicsemi.com/.../nfc_type2tag_format_dox.html When it comes to NFCID1 (Serial number) length, by default, Type 2 Tag examples in the SDK use a 7-byte-long UID.

[JeanFifre]

Okay thanks a lot for your reply, I hadn't read this documentation I guess I understood now !