Hello, I am using stm32f103 in my project. Software as GPIO_PinRemapConfig (GPIO_Remap_SWJ_JTAGDisable, ENABLE); I disabled it with the command. But now I can activate it back, I don't know how.

[DeveloperMan]

..

[Tesla DeLorean]

With BOOT0=HIGH your code will no longer run at reset, and you can recover/erase the device in that mode

[DeveloperMan]

So I can access jtag pins by interfering with this situation with hardware boot pin? Is that so?

[Tesla DeLorean]

Correct

You can protect the content of the flash from extraction with RDP/ROP (Read Out Protection) settings.

If you use an STM32 design that isn't 12+ years old you can also blow a fuse that disables the interface permanently. But you should think about how to use that, and how to update from within, before you brick the device and need ComponentSolderingDude to replace the IC

[DeveloperMan]

So I can access jtag pins by interfering with this situation with hardware boot pin? Is that so?

[Tesla DeLorean]

Yes, think of threat surface as a sphere, where the radius is the disparity in wits, and where the radius can increase over time

[TDK]

Yes. Hold BOOT0 high during reset and access the chip with JTAG or SWD.

[DeveloperMan]

Thanks for your interest.