hidden unique serial number in AVR chips?

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Does anybody know if there is something like a unique unchangeable factory preset serial number in the avr chips? This would be very handy.

Thanks, Tom

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Xmegas have that.

Stealing Proteus doesn't make you an engineer.

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Failing that put your own into each ones EEPROM (and set EESAVE so it won't be erased by ISP)

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All USB chips (for example AT90USB162) have unique number as well. It resides in a DFU, so it is not unchangeable. Alternatively you can make one by your own in EEPROM or FLASH during programming.

But if you need a seed for random number generator, you can use OSCCAL - it is pretty random (not uniformly and with rather poor resolution).

Mega chips have silicone revision value burned in, but it is not that unique, and accessible only via JTAG.. Definitely unchangeable.

No RSTDISBL, no fun!

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Dallas makes a tiny chip with a unique I/D code in it.

Leon Heller G1HSM

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Maxim purchased Dallas, but the Dallas name is still in use. Go to the Maxim home page:
http://www.maxim-ic.com/

use their web site search for:
silicon serial number

then you will find lots of these devices with different features and bus interfaces. They have a guaranteed unique, usually 48 bit permanent serial number. At least some of them for the Dallas 1-Wire Net were commonly available parts at places like DigiKey.

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The AT90USB646/647 and AT90USB1286/1287 have unique unchangeable 10 byte serial numbers located in the signature row (page 361 of datasheet dated 11/09). LUFA can make use of this number during USB enumeration as the device serial number.

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and also attiny 441 :)

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Rather appropriate image for resurrecting a 5-year dead thread:

katarcza's picture

 

laugh

 

In Oct  2010, Mike B wrote:
Maxim purchased Dallas, but the Dallas name is still in use

Not any more - the Dallas name is now purely historical.

 

silicon serial number

http://www.avrfreaks.net/comment...

 

 

And the SAM D20/D21/R21 also have a unique serial number

 

http://www.avrfreaks.net/comment...

 

 

Last Edited: Tue. Jul 14, 2015 - 06:18 AM
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ATMEGA48PB/88PB/168PB has a 9 byte unique ID code in each chip...

 

 

 

Last Edited: Thu. Sep 21, 2017 - 03:40 PM
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bigjosh2 wrote:
 a 9 digit (sic) unique ID code 

You mean 9 bytes (unless we're talking base 256)

 

And what a bizarre order!

 

(ISTR that the SAM D order was not  entirely straightforward, either)

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>You mean 9 bytes (unless we're talking base 256)

 

@awneil I was thinking in sexasexadecimal... :)

 

Fixed, Thanks!

 

>And what a bizarre order!

 

Right? I am hoping there is a method to the madness and maybe high 3 bytes are a static family code so you only need to user the lower 6 bytes in practice?

 

I will check and report back!

 

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There is no order. The bytes are their fabrication identifiers for each die (different bits of info). If you are using all the bytes for an id, you can take it anyway and it'll be unique. Mchip support may be forthcoming for what the bytes mean if you bother them. 

Last Edited: Thu. Sep 21, 2017 - 03:51 PM
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mroszko wrote:
There is no order. 

 

But the bytes are numbered in a bizarre sequence.

 

I agree - one can use them in whatever order one chooses.

 

IIRC, there was a gap in the SAM D ?

Last Edited: Thu. Sep 21, 2017 - 04:04 PM