Hi Giau, I hope you're doing well!
We provide a tool called the JN51xx Production Flash Programmer, which offers more options compared to the programming tool included with BeyondStudio IDE.
The "--key" argument when programming can be used to encrypt the device using an AES key, and there's also a bootloader security flag that could be useful.
The Production Flash Programmer can be found in this page, here (JN-SW-4107), along with its release notes and documentation.
Please let me know if you need any more information.
Best regards,
Sebastian
