UICR runtime write

[Dermot Murphy]

Hi,

What is the correct way to write to UICR at runtime?

I am using the code below but the MCU crashes on the first line with no call stack trace.

NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos ;
while (NRF_NVMC->READY == NVMC_READY_READY_Busy)
{
}

/* Copy the buffer to the UICR memory */
/* Bits which are 1 can be written as 0, bits which are 0 CANNOT be written as 1 */
ptr = (uint32_t*) (0x10001090U) ;
*ptr = field ;

NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos ;
while (NRF_NVMC->READY == NVMC_READY_READY_Busy)
{
}

Thanks

Dermot

[Jørgen Holmefjord]

Hi,

Are you using a softdevice in your application? If you are, then all access to the NVMC peripheral needs to go through the Flash API.

There is no API to write UICR while the softdevice is enabled, you need to disable the softdevice and re-enable it once writing is done.

Best regards,
Jørgen

[Dermot Murphy]

Hi Jorgen,

Thanks for the info.

Dermot