nRF534 - NFC undocumented registers

RE: nRF534 - NFC undocumented registers

Gabriele — Mon, 02 Aug 2021 14:06:30 GMT

Thank you Ketiljo

RE: nRF534 - NFC undocumented registers

ketiljo — Mon, 02 Aug 2021 13:46:41 GMT

The corresponding register for the nRF5340 is 0x4002D68C (default value is 0x38148)

So if you write the following:

nrfjprog -f NRF53 --memwr 0x5002D68C --val 0x38D48
nrfjprog -f NRF53 --memwr 0x5002D000 --val 1

you should have the correct setting for a fixed resistance. The NFC peripheral is the same on the nRF52840 and nRF5340

RE: nRF534 - NFC undocumented registers

Gabriele — Wed, 21 Jul 2021 13:49:47 GMT

Sure Torbjørn
Thanks

RE: nRF534 - NFC undocumented registers

ovrebekk — Wed, 21 Jul 2021 13:31:18 GMT

Thanks for the reference. I believe the same document should be valid for the nRF53 also.

Unfortunately all the people that have some experience with NFC antenna tuning are currently on holiday. I will have to get back to you on the other questions when they are starting to come back in August.

Best regards
Torbjørn

RE: nRF534 - NFC undocumented registers

Gabriele — Tue, 20 Jul 2021 14:44:38 GMT

Hello,
Over here you can find an application note.
Truth be told, the document refers to nRF52 SoCs (paragraph 4.2.1). I guess something similar ought exist in nRF5340.

RE: nRF534 - NFC undocumented registers

ovrebekk — Tue, 20 Jul 2021 14:19:23 GMT

Not quite sure what register you are referring to. Do you have a link to the text you mentioned?

There is some information on tuning the NFC antenna here.

Best regards
Torbjørn