Unique Device ID

RE: Unique Device ID

Tom — Mon, 25 Jul 2016 18:25:22 GMT

[quote]No ID in the chip is guaranteed to be unique, as they are all randomly generated in production of the chip.[/quote] If true uniqueness is required, writing a unique serial number (or similar) to a constant or NVM and recompiling for each unit is a possible solution. But this is time consuming for large quantities. Any other suggestions? We are considering using uVision5 to program.

RE: Unique Device ID

Paul — Tue, 04 Mar 2014 17:38:58 GMT

You need to look at your application for the "Unique ID". If all the ID's got uploaded to a database and linked to a server, You can always put a extra column to fix it, or even download it back to fix permanently. I still think the hash idea would work. If it is online, then server can assign an ID back. If it is offline application, I don't see too many reasons to really really have a "Unique" ID.

RE: Unique Device ID

Ole Morten — Tue, 04 Mar 2014 14:58:32 GMT

No ID in the chip is guaranteed to be unique, as they are all randomly generated in production of the chip. If you need a value that's guaranteed to be unique, this is hence something you'll have to do yourself in your own production flow.

You may also have use in taking a look at this question.

RE: Unique Device ID

Dave — Thu, 27 Feb 2014 20:01:05 GMT

Yeah. So, I looked at the MAC address ICs which have a EUI-48 id whereby 24bit is said to be a unique id (the other 24bit is manufactures code). That said, if you buy in batches over years, and they are assigned contiguously by ATMEL, common IDs will be encountered. Unless they do it by account, which I doubt.

URL: www.atmel.com/.../atmel-8807-seeprom-at24mac402-602-datasheet.pdf

The obvious solution is post production programming of a contiguous ID, but is an timely step for manufacturing when production numbers are high.

RE: Unique Device ID

Paul — Thu, 27 Feb 2014 18:45:03 GMT

Yes, statistically you will have common IDs. But you won't be able avoid that no matter what if you scale down a "guaranteed" 64-bit number to 32-bit. Even you understand how Nordic compiles the IDs, there is no way you can "pick out" 32-bit still unique numbers over the years.

RE: Unique Device ID

Dave — Thu, 27 Feb 2014 09:25:12 GMT

Thanks Paul. I thought of that but my understanding would be that statistically common IDs might be generated. I.e. if there are 10,000 of these devices being produced per year and they rely on a unique ID, the lower 16 bits of a hash may be common. Or am I misunderstanding this?

RE: Unique Device ID

Paul — Wed, 26 Feb 2014 17:01:49 GMT

Just apply a standard hash such as sha1 or md5 and then take the last 16 bits.