Which registers in the UICR of the nRF5340 are reserved for user access?

[Palmer Huang]

As far as I know, UICR->OTP should be similar to the UICR->CUSTOM register in the nRF52 series. However, I have learned that the nRF Secure Immutable Bootloader (NSIB) writes some parameters to the OTP registers. So, I would like to know which registers are reserved for user access?

[Palmer Huang]

Hi Naeem, any updates on this?

[Naeem Maroof]

Hi Gray,

I did not get any useful information, and I don't know the answer to your question.

Can you try to elaborate what you are doing currently and what you want to do?

If you could provide some example (code / commands) for better information and understanding of the issue, it would be good. 

[Palmer Huang]

Hi，Naeem,

I am using nrf5340 to develop a product, and I need to write the MAC address, sensor parameters, keys, etc. into UICR, and the length of these data is about 512 bytes. What I want to ask is which register should I write these data to?

[Naeem Maroof]

Hi Gray,

Both of the application and the network core (on nrf5340) have their own UICR registers.

Application Core UICR are not accessible from the Network core.

For writing to UICR registers, please see NVMC controller. 

App-core UICR base address is 0x00FF8000, and its OTP offset is 0x100.

Within the OTP region, there are 192 4-Byte registers which you can use to write your data values.

I have just compiled the Provisioning_Image sample, and I can see the following memory report.

[Palmer Huang]

Hi Naeem，

Sorry, my previous description might not be very clear.
I can understand that the OTP area (0xff8100~0xff83fb) is writable, but since I need to upgrade mcuboot, I enabled nRF Secure Immutable Bootloader(NSIB). Then after compiling, I saw that some registers of OTP (Provision partition) are occupied in NSIB, can you help me determine whether there are only 31 4-Bytes registers left available?

If yes, it is not enough for me, the parameter I want to flash is more than 31*4 bytes, can I move the Provision partition to the flash? Like the nRF52 series. If possible, can you provide an example?