UICR write example with nRF9160 and Zephyr

[SmallerPond]

I might be dense, but I'm not seeing any examples on how to write a value to UICR using Zephyr.  Does one exist?  If not, is there a guide somewhere on how to use NVS (I guess?) to write to UICR?  In our case we are trying to perform a one-time write of a 32-bit identifier to UICR and read it back on reset.

[helsing]

Hi James,

Here is an example showing how Pin Reset is configured in UICR during startup: https://github.com/nrfconnect/sdk-hal_nordic/blob/8f013ea950f41bf69b18bf688bfb0dd80a3fdc44/nrfx/mdk/system_nrf52840.c#L161

First, you have to enable write in CONFIG, then wait until READY, then write your identifier into where you would like it: NRF_UICR->CUSTOMER[n].