Locking micro to prevent download of code

[Ricko]

Hi,

where do you set programmatically (perhaps through a preprocessor directive) the option to lock the micro to prevent read/download of the flashed code but while obviously still allow for firmware updates?

Also I could not seem to find any such option in CubeIDE. Is it available there or do I need to use the CubeProgrammer?

Thank you

[Tesla DeLorean]

Simpler perhaps to engage writing of Option Bytes in your own code, and either engage automatically based on a check if currently locked in RDP, or command initiated via your user interface, along with mass erase to clear RDP1

[BarryWhit · Accepted solution]

Use CubeProgrammer's Option Byte pane to set RDP options (Readout Protection). Make sure to carefully read up on this feature first, so you don't hurt yourself. Setting RDP level 2 is irreversible.

Update: here's another pitfall story, of a near-brick even with RDP level 1.

Update2: 

AN5347: Arm® TrustZone® features for STM32L5 and STM32U5 Series

does a good job of scaring you with brick scenarios.

[Ricko]

Thank you both. :smiling_face_with_smiling_eyes: