STM32U5 RDP2 password accepted but ST-Link fails: DEV_TARGET_NOT_HALTED

[Gaurangthaker]

Hello ST Community,

I am working with an STM32U5 based board and facing serious issue related to RDP Level 2 and debug access. I am attempting to recover the device using STM32 Programmer CLI and Cube Programmer  but it is not responding as expected even after a successful RDP2 password unlock.

$ STM32_Programmer_CLI.exe -c port=swd mode=UR -unlockrdp2 0x18BBDDEF 0x19CCBBEF
-------------------------------------------------------------------
STM32CubeProgrammer v2.19.0
-------------------------------------------------------------------

ST-LINK SN : 003200253133510636303739
ST-LINK FW : V3J15M7B5S1
Board : STLINK-V3SET
Voltage : 3.54V
Error: Unable to get core ID
Error: No STM32 target found! If your product embeds Debug Authentication, please perform a discovery using Debug Authentication
Error: Unable to get core ID

ST-LINK SN : 003200253133510636303739
ST-LINK FW : V3J15M7B5S1
Board : STLINK-V3SET
Voltage : 3.54V

Unlock RDP2 password successfully done
Error: ST-LINK error (DEV_TARGET_NOT_HALTED)

I need help with:
1. why is the core still inaccessible even after RDP2 unlock?
2. Is the device stuck due to TrustZone configuration or another misconfiguration?
3. Solution on above configuration

[Bubbles]

Hello @Gaurangthaker,

did you follow the How to regress from RDP level 2 to RDP level 0 on ... - STMicroelectronics Community exactly, or what were your steps?

also check the discussion under the article, there may be some answer.

BR,

J