on
2023-05-04
3:02 AM
- edited on
2025-08-01
6:03 AM
by
Laurids_PETERSE
The aim of this article is to provide guideline for disabling Trustzone on STM32U5.
As you can see when connecting your board to STM32CubeProgrammer and checking the option bytes, TZEN is checked (TrustZone® enabled).
To disable TrustZone®, you have to:
Step 1: Connect Boot0 to VDD on your board:
This consists on connecting PH3 pin (CN11 pin 7) to VDD (CN11 pin 5).
Step 2: Connect your board with STM32CubeProgrammer in "hot plug" Mode.
Step 3: Switch RDP value in “readout protection” to level 1, then click on apply.
Step 4:
Step 5: Then click on apply to program the option bytes.
Step 6: Disconnect your board to STM32CubeProgrammer.
Step 7: Disconnect Boot0 to VDD.
Step 8: Connect again your board with STM32CubeProgrammer and make sure that TrustZone® is disabled(TZEN unchecked).
Reproduce this procedure faithfully otherwise the TrustZone® will not be disabled.