SBSFU on Nucleo-G474 can't jump to the custom user application slot

[JShih.2]

Hi,

I'm testing SBSFU on Nucleo-G474RE, I have no problem to run up the reference code of SBSFU, but somehow secure boot loader didn't jump to my user application after the upgrade via UART Y-Modem after use my application code instead of original user application code in SBSFU.

My steps are,

1. Build SecureEngine.
2. Build Secure SBSFU and download to my Nucleo board.
3. SBSFU shows up on Tera Term.
4. Use Y-Modem protocol to download encrypted and signed firmware image via UART.
5. SBSFU starts to run firmware upgrade procedure.

I created two user application images,

• SBSFU reference encrypted and signed firmware image.
• Custom application used the same way of SBSFU reference user application to encrypt and sign firmware image.

Results are,

• Everything works well and can jump to the application when download reference image
• No response after download, upgrade and jump to my custom user application. Expectation is to see the welcome print on TeraTerm after jump to my application.

Is there any suggestion to debug this problem?

Thanks.

James S.

[Jocelyn RICARD]

Hello James,

First I would suggest reusing the material we provide in the MOOC dedicated to SBSFU:

https://www.youtube.com/playlist?list=PLnMKNibPkDnGd7J7fV7tr-4xIBwkNfD--

In video number 4, I explain how to do such thing. And you can get the scripts used.

This should help you.

Also, if you are sure the SBSFU is launching your application, you can just launch the debugger (without download, just attach to target). Put a breakpoint on the reset handler, resume the debug and press reset. You should break at the very beginning of your application and then go step by step.

I hope this will help

Best regards

Jocelyn