How to LPC55S14 Flash Read Protection

[just_lee]

I am currently creating a product using the LPC55S14.
Once the product code is written, I want to prevent external reading of the contents of the MCU Flash to protect the product code.
I need to be able to read/write using the Flash API to update the product.
However, my skills are limited and I have looked at the LPC55S1X User Manual (UM11295), but I don't understand how to protect the Flash.
I was wondering if there is any reference to protect the Flash.

[Alice_Yang]

Hello @just_lee 

"I need to be able to read/write using the Flash API to update the product."

->> Do you mean you still need to be able to read/write flash after Flash Read Protection? 

Want to disable SWD? 

BR

Alice

[just_lee]

yes. I should be able to read/write internally after flash read protection. I want to prevent others from watching my program using SWD from outside. I want to disable SWD.

However, I am reading UM11295 (LPC55S1x/LPC551x User Manual), but I don't understand how to disable SWD. Looking for additional documents or examples related to this.

I would appreciate it if you could help me.

[Alice_Yang · Accepted solution]

Hello @just_lee 

Please refer to this thread:

https://community.nxp.com/t5/LPC-Microcontrollers-Knowledge/LPC55-Disable-ISP-and-SWD-to-utilize-cod...  

Pay attention, this article includes disable SWD and disable ISP. Please do NOT disable ISP if you still want to read/write flash. Thus you can through ISP mode to read/write.

BR

Alice

[just_lee]

Thank you for your reply.
I succeeded in turning off the ISP and SWD through the link you told me.
However, I realized that it is impossible to use that MCU again if you do not use UART communication with the outside world.
I am now going to study how to use MCU again even if I turn off ISP and SWD.
Currently, I am studying through the document in the link.
https://www.nxp.com/docs/en/application-note/AN13037.pdf
If I have any questions, I will ask for help again.
Thank you again for your help.