nRF51822 - ID

RE: nRF51822 - ID

awneil — Fri, 12 Jul 2019 08:45:53 GMT

[quote userid="4908" url="~/f/nordic-q-a/6452/nrf51822---id/22499"]Have you read the nRF51 Reference Manual (UICR and FICR chapters)? You will find the answers there[/quote]

Actually, the answer that you will find there is wrong!

😮

The manuals incorrectly state that the DEVICEID is "unique"; it is not - it is random.

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

RE: nRF51822 - ID

Susheel Nuguru — Mon, 20 Apr 2015 10:18:35 GMT

what do you mean by 5 to 6 tags?

RE: nRF51822 - ID

Jose Xavier — Fri, 17 Apr 2015 11:33:51 GMT

thank you all, I think it is ok as per kit it will be using 5 to 6 tags and if there is a collision is it possible to change the tag.

RE: nRF51822 - ID

Susheel Nuguru — Wed, 15 Apr 2015 12:39:01 GMT

This are 64bit DeviceID, the odds of collision are fairly small, but non zero. If this is something very important for your design, you can manage this easily in your production by using nrfjprog command line tool.

RE: nRF51822 - ID

John — Wed, 15 Apr 2015 12:05:35 GMT

Reminds me of a comment I saw in code that generated keys into a hash table and didn't check for collisions: "What are the odds?"

RE: nRF51822 - ID

Susheel Nuguru — Wed, 15 Apr 2015 06:41:39 GMT

The Chip ID is not guarenteed to be unique. These numbers are set in production and should be random numbers (FIPS compliant).

devzone.nordicsemi.com/.../

RE: nRF51822 - ID

endnode — Fri, 10 Apr 2015 13:59:12 GMT

Hi Xavier,

Have you read the nRF51 Reference Manual (UICR and FICR chapters)? You will find the answers there (or you can see other posts on this forum such as: devzone.nordicsemi.com/.../ ). Basically you have 8-byte ID burned into the chip and additional register area which can hold some diversified ID at the programming stage.

Cheers Jan