Unable to call nrf_power_gpregret_set after nrf_sdh_enable_request

[Jacob]

Hello, We're using SDK v14 and nRF52. To pass some data between reboots we're using the general purpose retention register. However, it seems like it's impossible to call nrf_power_gpregret_set after the SoftDevice has been initialized.

Basically the system hangs for a while and then reboots. Calling nrf_power_gpregret_set the line before nrf_sdh_enable_request works.

I can't seem to find anything in the documentation about this.

I'm pretty sure this worked with SDK v13 (although the SoftDevice had another API back then, as far as I can recall).

Thanks, Jacob

[Sigurd]

Hi,

After the SoftDevice is enabled you have restricted access to the NRF_POWER register(see this link).

You should therefore use the SoftDevice API function sd_power_gpregret_set() in order to set bits in the GPREGRET register after the SoftDevice is enabled.