George, Is it in the realm of possibility, that a terminal which has developed a hardware defect, could spontaneously change the last 16 bytes of the UUID?

There would have had to have been a serious hardware defect.  The UUID would have been the least of your worries.

Sorry, that wasn't very clear.  I had assumed that if the hardware wasn't changing there was no change in the OS that was loaded either.  Let me be a bit more explicit. Replace that last sentence with: To answer your question, if the hardware in the terminal is not changing, then the lower bytes of the UUID can not change.  If the OS does not change, then the upper bytes of the UUID can not change. As an example, pick up an MC55 WM6.1, MC75 WM6.1 and MC70 WM5.0.  Navigate to Start->Settings->System->System Info.  In the MC75 and MC55 terminals you should see the same UUID Part 1 and the MC70 will be different.  But, UUID Part 2 will be different in all three.

Thanks, George....excuse my thickness here...., can I assume that if a customer upgrades their terminal from 5.0 to 6.1 or 6.1 to 6.5, (for my case an MC75 from 6.1 to 6.5) that the upper bytes of the UUID will definitely change? AND, the upper bytes will definitely NOT change if the terminal is just upgraded -OR_ downgraded to a different BSP within the same OS?

For the most part you are correct.  Unfortunately, there is no hard and fast rule on this.  Since we're given the upper 16 bytes from Microsoft, they could make a change between AKUs. As a rule of thumb, I would expect that any WM5 BSP would have the same upper bytes.  Any WM6.1 BSP would have the same upper bytes, but different than WM5.  Any WM6.5 BSP would have the same upper bytes, but different than WM5 and WM6.1

But this appears to be the opposite of SPR 18919. The SPR concerns 2 terminals with the same UUID, or 2 different serial numbers with the same UUID My issue is terminals changing UUID's or 1 serial number where the UUID changed, supposedly not due to hardware change.

The UUID will not change if the hardware does not change.  Let's be clear about the UUID.  It is a 32 byte value.  The upper 16 bytes are issued by Microsoft and are unique for each OEM.  The value may change for each major OS change (WM5.0 may be different than WM6.1 which may be different than WM6.5).  For WM6.1 Motorola is 001346E604EB0108.  Numonyx (the flash manufacturer) burns a unique serial number into each device that they ship to Motorola.  This serial number is used when determining the lower 16 bytes.  As you can see, the UUID can not change when the OS changes or if a clean boot is performed.  It is not calculated at boot time, it is read at boot time. To answer your question, if the hardware in the terminal is not changing, then the UUID can not change.

George, regarding your last sentence "To answer your question, if the hardware in the terminal is not changing, then the UUID can not change. " Doesn't this contradict your previous statement "The value may change for each major OS change (WM5.0 may be different than WM6.1 which may be different than WM6.5)." Because I am assuming that if you Upgrade a device from 5.0 to 6.1 or 6.1 to 6.5  then the upper value will change. Please clarify for me.

Thanks George. I do have a further question regarding the UUID part 2 for the MC75 (MC55). Although this part is unique, how is this part calculated? Is it based on a time stamp (as first part was on the MC70).The reason I ask is that if the UUID part 2 on the MC75 is based on a time stamp then this would guarantee that it is unique across all Motorola devices - since part one on the older devices was also based on a time stamp. I would recommend to customer using all 16 bytes of UUID but then the customer has to change whole system as its setup only for 8 bytes (64 bits).

1.  8/03/2010 2:55 PM 2.  3 Day 3. MC7596 4. BSP 27/35 5.2189402 With the previous posts in mind, maybe someone can help me with this report from a Partner. They claim that when they enter serial number of MC7596 in MSP, eight out of 1400 deployed units show there was a previous UUID for this serial number. Barring that these have been repaired, what could cause this. I read that part of this number is generated by the OS at each boot-up. Could a downgrade of a BSP version cause this or only a hardware change? What constitutes a hardware change that effects UUID? Is there ANY possibility that MSP could be incorrect here?

The UUID is hard coded in the flash.  Refer to SPR 18919.

My first post was incorrect with regards to the UUID so let me start again. For MC75 product the FLASH PROM purchased for the device contains a 64 bit Unique Identifier which is used as the first part of the UUID.  If this part is replaced as part of a repair then this part of the UUID will change.  The lower 48 bits of the UUID is provided by Microsoft to Motorola.  You'll see that all Motorola EMB devices use the same lower 48 bits.  The remaining 16 bits is a product ID which will be the same across the family of products.

Can you please again clarify UUID Part 1 and UUID Part 2 for MC75. I see the same UUID Part 1 (001346E604EB0108) on all MC75 WM 6.1 and also MC55 WM 6.1. However UUID Part 2 seems unique. Can you confirm how the UUID on this device is built up? and if this applies to all other Windows Mobile 6.1 devicessuch as the MC9094, MC7094 (that have been upgraded)? But I saw different UUID Part 1 than on MC55 or MC75.Thanks for clarificationMilan

The UUID contains a field that is OEM specific.  Motorola (Symbol) was assigned a number by Microsoft. That's why some of the number is the same from terminal to terminal.  A second part is product dependent and the final section is unique for each terminal. To answer the questions (apply to both ESN and UUID) 1) Stored in flash 2) Entered at the end of the manufacturing process 3) ---repair process questions need to be answered by service ---

Further queries if anyone can assist, from the Australia Motorola Service Contract Manager

Electronic Serial Number - ESN

            Where is it stored? (Hardware / Software / Main board / Sub board etc)

                        NVM as in ROM?

            Who enters it?  

                        Original Device Manufacturer

            Is it re-entered during the repair process? If yes how?

                        If board is replaced would ESN change as well?

 

The Unique Number - UUID

            Where is it stored? (Hardware / Software / Main board / Sub board etc)

                        Calculated by the OS but where is it stored? RAM or ROM?

            Who enters it?

                        Calculated each time when the OS boot up or once only?

            Why is it in two parts UUID1 and UUID2  

                        Is this a Microsoft decision?

            Is it re-entered during the repair process? If yes how?

                        ???

Charlies answered these questions: ESN- Stored in Flash, which is Non Volatile Memory but is not the same as ROM since it can be rewritten when needed. Burned in by the OEM. If the board is replaced, since the ESN is burned into the memory located on the board, the ESN would be reburned in by service. UUID- Calculated by the OS but stored in Flash, Non Volatile Memory but not the same as ROM since it can be rewritten as needed. It is calculated by the OS each time the device boots up. There are 2 parts, UUID 1 which is calculated by Microsoft and UUID 2 which is Motorola Specific. The OS at all times calculates and recalculates the UUID.  If hardware changes, OS recalculates.

ESN 1 - Stored in a configuration area in flash 2 - Manufacturing 3 - I can't answer that question.  You'll need to talk to service UUID 1 - Calculated by OS 2 - No one 3 - No, it is recalculated if hardware changes