Reading from the UICR / OTP registers on the nRF5340 during runtime

RE: Reading from the UICR / OTP registers on the nRF5340 during runtime

ColinC — Fri, 06 Mar 2026 08:18:39 GMT

Hi Vidar,

Thank you for the quick response, I'll have a look at it.

RE: Reading from the UICR / OTP registers on the nRF5340 during runtime

Vidar Berg — Wed, 04 Mar 2026 12:19:27 GMT

Yes, via a secure service exposed by tf-m, please see this post: https://devzone.nordicsemi.com/f/nordic-q-a/113714/static-partition-alignment

Cheers,

Vidar

RE: Reading from the UICR / OTP registers on the nRF5340 during runtime

ColinC — Wed, 04 Mar 2026 12:05:02 GMT

I am also trying to read from the UICR->OTP register, though from a non-secure context (i.e the target is based on nrf5340_cpuapp_ns). Is this possible altogether? If no what the right way be to go about this?

Cheers

Colin

RE: Reading from the UICR / OTP registers on the nRF5340 during runtime

cal.rubbo — Thu, 21 Mar 2024 20:41:41 GMT

Wonderful! I verified it now. Glad it was something so simple, thanks for your help

RE: Reading from the UICR / OTP registers on the nRF5340 during runtime

Vidar Berg — Thu, 21 Mar 2024 13:52:24 GMT

Hello,

I'm not aware of any limitations with reading the UICR register when you run the code in secure mode (i.e., built for the nRF5340dk_nrf5340_cpuapp target). Please try the attached code below and see if you get the same result.

devzone.nordicsemi.com/.../hello_5F00_world_5F00_uicr.zip

I first set the OTP register with nrfjprog:

nrfjprog --memwr 0x00FF8100 --val 0x12345

Then I ran the example and received the following log output:

*** Booting nRF Connect SDK v2.5.2 ***
NRF_UICR->OTP[0] : 0x12345

Best regards,

Vidar