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Mil , 06-07-2026, 07:01 AM

Good day guys,
I would like to ask for some help on how to remove the "The device is protected" The Read Protection is already set to OFF, but I am still getting this error.

I am planning to dump the contents of the STM32F103RBT6 so I can create a backup of the firmware.

Thank you in advance to anyone who can help.

, 06-07-2026, 07:03 AM

🤖 In the meantime, here’s a response from the [FEDEVEL AI HW Assistant]().
It helps to find relevant resources for your question, but it may make mistakes as it’s still in early development.

This is the response from the AI Assistant:
The "device is protected" error in STM32 devices can persist even with RDP set to OFF due to several factors covered in our hardware security discussions:

1. **Debug Interface Disabled**: Some STM32 configurations disable SWD/JTAG interfaces through option bytes. Verify these settings using STM32CubeProgrammer's "Option Bytes" tab. If SWD is disabled, you'll need to force communication through bootloader mode (BOOT0 pin high) to re-enable it.

2. **Residual Protection States**:
- Try a full power cycle (remove all power for 10+ seconds)
- Use STM32CubeProgrammer's "Connect Under Reset" feature
- Check for "PCROP" (Proprietary Code Read Out Protection) settings in option bytes

3. **Hardware-Level Protections** (if software methods fail):
As shown in hardware hacking examples [like this voltage glitching demo](https://www.youtube.com/watch?v=Ifb6nKOu2Go&t=783), you might need to:
- Target the RDP check during boot sequence
- Use a debug probe (J-Link/ST-Link) to monitor reset behavior
- Consider clock glitching if voltage manipulation doesn't work

4. **Firmware-Specific Protections**:
Some custom bootloaders implement additional software checks. In these cases:
- Try dumping memory immediately after power-on
- Use boundary-scan techniques to intercept flash communication
- Analyze power-up sequence with a logic analyzer [as shown here](https://www.youtube.com/watch?v=LvJhXDc_siI&t=1841)

If all else fails, professional tools like Xeltek programmers or JTAG-based extraction may be required.

, 06-07-2026, 07:03 AM

For critical applications, STM32's built-in secure boot features would normally prevent this kind of dumping - the fact you're seeing this suggests either a configuration error or non-standard protection scheme.

You can continue chatting with the AI Assistant here:
https://fedevel.com/hw-assistant