Mesh DFU example - How to write information to NRF_UICR->CUSTOMER

[pkoenig]

I would like to store unit configuration information into the UICR "customer" area. This is done only once, on first startup, saving configuration received from the host.

Tried using NRF_NVMC, but looks like app or soft device is somehow crashing.

Using nrf5_SDK_for_Mesh_v4.1.0_src\examples\dfu\dfu_nrf52832_xxAA_s132_7_0_1.emProject

Thanks, Piotr

[haakonsh]

Hey Piotr, 

In order to use the NVMC directly, you have to disable the SoftDevice or use the SoftDevice Timeslot API to request a timeslot where you've got full control of the MCU. See sd_radio_session_open, sd_radio_request, sd_radio_session_close, Concurrent multiprotocol implementation using the Radio Timeslot API, and Radio Timeslot API usage scenarios. 

Alternatively, you can try the sd_flash_write API. It uses the internal SoftDevice scheduler to schedule the use of the NVMC. 

BR,
Håkon Holdhus

[pkoenig]

sd_flash_write returns an error 16. Is this expected behavior for the UICR area?

Source:
addStrHex("dst: 0x", NRF_UICR->CUSTOMER, "\n");
addStrHex("src: 0x", eeBuffer, "\n");
rv = sd_flash_write (NRF_UICR->CUSTOMER, (uint32_t const *)eeBuffer, 2);
addStrDec("sd_flash_write: ", rv, "\n");

Consolde:
[11]dst: 0x10001080
[0]src: 0x200033f4
[0]sd_flash_write: 16

[haakonsh]

That's an NRF_ERROR_INVALID_ADDR, so sd_flash_write does not support writing to UICR. 

Then it's back to these two options. Since you're only going to do this once I suggest you temporarily disable the SoftDevice while using the NVMC. 

haakonsh said:

In order to use the NVMC directly, you have to disable the SoftDevice or use the SoftDevice Timeslot API to request a timeslot where you've got full control of the MCU. See sd_radio_session_open, sd_radio_request, sd_radio_session_close, Concurrent multiprotocol implementation using the Radio Timeslot API, and Radio Timeslot API usage scenarios. 

[pkoenig]

OK, with sd_softdevice_disable function nrf_flash_write worked. I can reset and restart the device at this point, but possibly the sd could be enabled again, but I am not sure about the function parameters. We do have 32kHz xtal for the low frequency clock, as in the reference design.

SVCALL(SD_SOFTDEVICE_ENABLE, uint32_t, sd_softdevice_enable(nrf_clock_lf_cfg_t const * p_clock_lf_cfg, nrf_fault_handler_t fault_handler));

Thanks, Piotr

[haakonsh]

Your application already enables the SoftDevice every time you reset the CPU, so if you reset the device/CPU after writing to UICR then there's nothing else that you need to do.