Flash / app protect factory state of the nRF5340

[puz_md]

Hello,

I noticed that our self-produced PCB's with a nRF5340 SoC all have the cores locked upon delivery (probably app protect is activated), and have to be recovered before we can flash them.

Why is this the case? Does the nRF5340 come with a pre-programmed firmware (bootloader)? If so, where is this documented?

Best regards,
Michael

[Sigurd Hellesvik]

Hi,

See NCS APPROTECT docs:

So it is basically on by default in nRF5340, even though it comes shipped without firmware.

Regards,
Sigurd Hellesvik

[puz_md]

Thanks, that helped understanding the strange behavior!