How are the DEVICEID, DEVICEADDR, ER, & IR values set in the FICR?

[Andrew Fernandes]

I have looked through both the nRF51822 Reference Manual and Product Specification, and have searched through this forum, but to no avail so far.

Could I please get a definitive answer from Nordic on how the FICR values referenced in the title are set?

Specifically:

• Is the DEVICEID a random 64-bit value, or is it guaranteed to be unique?
• On all the modules I have worked with DEVICEADDRTYPE is set to "random" and DEVICEADDR has its most significant bit set indicating it is a random, not a static address. Again, is this truly random, or is it guaranteed to be unique?
• In a similar vein, does Nordic support burning static addresses into DEVICEADDR for custom orders if the address block is supplied by the customer?
• Lastly, how are the values in ER and IR generated, and are they used at all by either the chip or the SoftDevices? I have looked through several versions of the SDK, and they do not appear to be used from any source file, but it is not clear if any SD uses them.

Thank you very much!

[Susheel Nuguru]

DEVICEID, DEVICEADDR , ER and IR are randomly generated (FIPS compliant) at time of production. devzone.nordicsemi.com/.../ devzone.nordicsemi.com/.../

DEVICEADDRTYPE is having its lowest bit as '1' set to random. You cannot change these values.

[Andrew Fernandes]

That's awesome, Aryan, thank you!

I had seen several comments in the forum that said DEVICEID and DEVICEADDR were "random" or "unique", and it wasn't clear precisely what was meant.

The phrase "FIPS-compliant random" tells me very precisely how they are generated. Cheers!

[awneil]

Andrew Fernandes said:

I had seen several comments in the forum that said DEVICEID and DEVICEADDR were "random" or "unique", and it wasn't clear precisely what was meant.

The Product Specifications incorrectly state that the DEVICEID is "unique".

https://devzone.nordicsemi.com/f/nordic-q-a/49664/deviceid-is-unique---but-is-it-random/198061#198061