How to disable Read Protection Level 2 in stm32l152c series microcontroller?

The STM32 has a read-out protection level 2 feature adjusted from ST-LINK Utility App (Options Bytes) so code cannot be read out via the debug interface (SWD) or any other way.

There was an explanation,ST Electronics website. I tried the proposed app named as Device Firmware Update (DFU). However, it did not work. This is the MCU I work on. In read out protection, Level 2 is selected and applied. After that, MCU cannot be seen or communicated.

Solution 1:

RDP Level 2 can't be disabled.

It is in a permanent state, debug interfaces are disabled, the factory bootloader is disabled.

In RDP L2 only a custom bootloader (ie code running from the chip FLASH memory) can modify the FLASH, But it cant disable the protection.\

You need to physically replace the microcontroller. At the moment your board is bricked and there is no way of unbricking it