NFC via nrfjprog

RE: NFC via nrfjprog

mathiaso — Wed, 22 Nov 2023 09:23:44 GMT

Hi, Kevin!

It is correct that these are internal registers. On the nRF5340 you should be able to use the same offsets as for the nRF52840, in the NFC antenna tuning blog post you linked to. The only thing you have to change in the register address is the base, which is:

0x40005000 for the nRF52840.
Depending on the instance used, 0x5002D000 or 0x4002D000 for the nRF5340.

Thus, instead of
nrfjprog -f NRF52 --memwr 0x4000568C --val 0x38D48
nrfjprog -f NRF52 --memwr 0x40005000 --val 1
used for the nRF52840.

It should work to use, e.g.,
nrfjprog -f NRF53 --memwr 0x5002D68C --val 0x38D48
nrfjprog -f NRF53 --memwr 0x5002D000 --val 1
for the nRF5340 (if using the NFCT : S instance).

Btw, it should also work to not include -f NRF53 in the command. Thus, only use
nrfjprog --memwr 0x5002D68C --val 0x38D48
nrfjprog --memwr 0x5002D000 --val 1
in the example above.

Best regards,
Mathias

RE: NFC via nrfjprog

Stew — Thu, 16 Nov 2023 16:59:52 GMT

I likewise am wondering what the nrfjprog commands need to be for the nRF5340 for NFC antenna tuning. The register addresses specified for the nRF52840 and nRF52832 seem to be internal-only registers not documented in the public product specification, and the instructions are different from each other. What are the equivalent nrfjprog commands needed for the nRF5340 for NFC antenna tuning?

RE: NFC via nrfjprog

mathiaso — Fri, 20 Oct 2023 11:11:25 GMT

Hi, Brad!

There is a White Paper for tuning the NFC antenna of the nRF52832, found here. The same procedure should be possible to follow for the nRF5340.

If you have a VNA, there's no need to power the chip. But maybe you don't have that?

Best regards,
Mathias