LPC MicrocontrollersのトピックRe: Locking Sections of the LPC55S2x Flash

Locking Sections of the LPC55S2x Flash

sachin_patel — Wed, 19 May 2021 07:21:21 GMT

Hi,

Is it possible to lock specific sections of the LPC55S2x flash (the user data region)? If the flash can be locked, can it be unlocked from within the locked portion of flash?

Kind regards,

Sachin Patel

Re: Locking Sections of the LPC55S2x Flash

xiangjun_rong — Wed, 19 May 2021 09:02:15 GMT

Hi, Sachia,

As far as I know that the LPC55S2x does not support the feature to lock a page, or section.

Hope it can help you

XiangJun Rong

Re: Locking Sections of the LPC55S2x Flash

sachin_patel — Wed, 19 May 2021 09:23:49 GMT

Hi @xiangjun_rong

Thanks for your response.

What choices do I have regarding preventing change to my software?

Can I then use the IAP FFR Driver through the CMPA configuration to enforce a signature check and SHA256 validation on the image on boot?
What happens if this check fails?

Thanks,

Sachin Patel

Re: Locking Sections of the LPC55S2x Flash

xiangjun_rong — Wed, 19 May 2021 09:45:05 GMT

Hi,

Pls refer to the an13037.pdf from the link:

https://www.nxp.com.cn/docs/en/application-note/AN13037.pdf

It talks about how to block SWD and protect customer code in flash.

XiangJun rong

Re: Locking Sections of the LPC55S2x Flash

sachin_patel — Fri, 21 May 2021 14:56:10 GMT

Hi,

This is not what I am asking about.

Is there a way to ensure that the flash remains unchanged during operation, such as a flash write protect?

Secure Boot is an option, but it does not ensure the image is not altered at runtime, only on startup, which isn’t quite what I am looking for.

Thanks,

Sachin Patel

Re: Locking Sections of the LPC55S2x Flash

xiangjun_rong — Tue, 25 May 2021 10:12:03 GMT

Hi,

Unfortunately, there is not a mechanism to protect flash from erasing/programming.

Pls refer to the Chapter 5: LPC55S6x/LPC55S2x/LPC552x Flash in UM11126.pdf.

Hope it can help you

XiangJun Rong