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By graynomad
#132191
As I understand it the USN is a 128-bit number easily accessible, however for my purposes 128 bits is just a tad of an overkill, 32 would be about right.

Does anyone know exactly how this number is generated? If it's truly random I can use any of the 32-bit words. If it's an incrementing number generated in the factory I can use the least significant word as it won't roll over in my lifetime.

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Rob
By colinb
#133006
Maybe it's easiest if you don't assume anything about the number and do some hash function 128 bits -> 32 bits, even as simple as XORing the four words together.
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By graynomad
#133008
Yep I will probably do something like that. I don't have any chips yet so I can wait until I read some values and make a judgment based on what I see. If I get numbers like 00000000014ef1d3e... I can probably assume incrementing numbers. However if all words have data then maybe they are random.

I'm new to LPCs and finding the data a bit sparse, maybe I just don't know where to look but I think AVR data sheets are more informative and there's more code examples around. Still the 122x is a better choice for my app so I'll struggle on :)

I don't suppose there's an equivalent forum to AVRfreaks by any chance?

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Rob