UNIQUEIDn bit layout?

Hello Forum User,

The requirement for having a 128 bit UNIQUE ID allows the user to select larger random number seeds. You can run a Hash and make a 32 bit number,

Regards
Amit

Hi Amit,

Thank you for the response.

Yes. I could run a hash, but according to data sheet of the processor the UID is not random, so I took that to mean it had a defined structure.  If the bit layout only varies in some bit locations for a given processor part# then that reduces the set of possible values signicantly.  

Are you saying that any 128 bit value is possible for any Tiva product?

Thanks.

Hello Forum User,

Yes, it is not a random number but it is not possible for 2 TM4C devices to have the same number.

Regards
Amit

 Amit,

Checking from the DS and Do test 4-5 PCs Board , the ID is not same.

 

Hello Johnny,

And that is what I said. It is not the same for any 2 TM4C129x device

Regards
Amit

I have a Tiva TM4C1294NCPDT that I need 32 bits to be unique for security . I see that the TIVA has 4 registers, Register 182 through 185  AKA  UNIQUEID0 through UNIQUEIE3 that can be used but I wanted to know if I am only need 32 bits is there one of the 4 register that could be used that would be guaranteed to be unique for each different CPU?  In other words, would I get a unique value for each CPU if I only used one of the 4 registers and if so which of the 4 registers? 

What does the following mean?  "Checking from the DS and Do test 4-5 PCs Board"   etc? 

What is the DS and Do?

Doug

Hello Doug,

No. There is no single 32 bit value. The UNIQUEIDn is 128 bit only. DS would mean Data Sheet and I am sure Do means the verb "do"

Regards
Amit