RE: which registers cant be erasable in nrf52, which can be possible to Read/Write

Roger Clark — Fri, 28 Jul 2017 22:53:31 GMT

Have you considered using the MAC address as the serial? It comes pre programmed.

But I am not sure if they are absolutely guaranteed to be unique

RE: which registers cant be erasable in nrf52, which can be possible to Read/Write

Jørgen Holmefjord — Fri, 28 Jul 2017 12:40:59 GMT

Hi,

I think UICR is the best alternative for storing serial number. You have a couple of options to leave the serial in UICR when flashing your application:

Use --sectorerase option in combination with --program when flashing, instead of --eraseall. With this option, only the targeted non-volatile memory pages, excluding UICR will be erased.
If you need to erase whole chip, you can read UICR before erasing, and reflash it after application:

nrfjprog --readuicr uicr.hex

nrfjprog --eraseall

nrfjprog --program application.hex

nrfjprog --program uicr.hex

Best regards,

Jørgen