How to read protect STM32 microcontrollers

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Pretty much all that is needed to enable RDP (read protection) is to enable level 1 of the protection by writing values between 0xAA - 0xCC to a specific register.  


If you are using the STM32 HAL library you can check my integration as part of the function FlashAdapter_setReadProtection and function ActivateProtection. After enabling RDP level 1 the whole flash will be read-protected. Once you decide to disable it the whole flash will be wiped out and no one will be able to read your binary.


This is now part of the IMBootlaoder code.
Once when you enable RDP protection all code is protected. The cool thing you can still update your firmware code by using the IMFlahser application, without disabling RDP. 

You can ignore PCROP (Proprietary code readout protection). It is a cool feature that SMT32 also has, but I'll cover this in some future posts. 

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