AM623: Secure Boot Key Flash Failure over DFU-USB in Factory Setup - AM6231

RJ DJ

Part Number: AM623

Hi TI Team,

We are facing an issue while flashing secure boot keys on our custom boards using DFU over USB.

In the factory environment, when programming a batch of around 20 boards, typically 3–4 boards fail during the secure boot key loading process on the first attempt.

observation: some boards fail to flash secure boot keys on the first try, but succeed after 2–4 retries.

Additional Details:

Interface used: DFU over USB
We are using a single (short) certificate for generating secure boot keys.
The VPP configuration differs slightly based on our custom board design.
Failure pattern: Intermittent failure on first attempt, success after multiple retries or the very next retry
Occurrence rate: 15–20% of boards in factory batches

Any suggestions on debugging steps or improving robustness in factory programming would be very helpful.

Regards,

3 months ago

0 Prashant Shivhare 3 months ago

TI__Guru* 84791 points

Hello,

Could you please share more information about the failure like do you not see any logs on the UART?

Thanks!

0 RJ DJ 3 months ago in reply to Prashant Shivhare

Intellectual 426 points

Hi ,

The logs below show failures in the initial attempts. After a few (2-3)retries, the process succeeds. However, we observed that in the failure cases, the success log message appears to be incomplete or partially printed.

Incomplete message example:
---------------------------------
Starting Keywriting
GPIO BASE ADDRESS =600000  
GPIO PIN =49
Enabled VPP
keys Certificate found: 0x43c16800
Keywriter Debug Response:0x0 
Succes


-----------------------
line number 4 and 5 added for debug purpose .

Regards,

0 Prashant Shivhare 3 months ago in reply to RJ DJ

TI__Guru* 84791 points

Hello,

What is the Keywriter version and the MCU+ SDK version you are using?

0 RJ DJ 3 months ago in reply to Prashant Shivhare

Intellectual 426 points

hello,

key writer version :09.00.00 (as per manifest file )

MCU+SDK version:09_02_01_06

regards,

0 Prashant Shivhare 3 months ago in reply to RJ DJ

TI__Guru* 84791 points

Hello,

Could you please use the latest keywriter version available (v11.01) with the expected MCU+ SDK version as mentioned in the keywriter user guide?

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AM623: Secure Boot Key Flash Failure over DFU-USB in Factory Setup - AM6231