NFC via nrfjprog

[rockerderek]

Hi I'd like to turn on the NFC transmitter via the registers. Would this accomplish that task?

nrfjprog --coprocessor CP_APPLICATION --memwr 0x5002D000 --val 0x1

nrfjprog --coprocessor CP_APPLICATION --memwr 0x5002D00C --val 0x1

I couldn't find a sample to do this for the nrf5340. We are simply tuning our antenna and need to measure the dBm output against our pi network.

[Stew]

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?

[mathiaso]

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