download via debbuger disable system bootloader.

[Arkady1]

Hi,

In my system host mcu update firmware in slave stm32g071cb

Some times I found that host controller cannot call embdedded bootloader by pulling up boot0 and reset via pins . After reset always starts main app instead of bootloader. I lost few hours when understand how to fix this and why this issue occures.

Just one download firmware via st-link makes calling system bootloader (via boot0 and reset pins) impossibe. To solve this problem helps only powering off mcu.

If the system bootloader alive again I can use it many times without powering off mcu. (untill st-link is used again)

Does anybody can help to understand how this can be.

Thank you!

[TDK]

Check that the option bytes do not overrule the BOOT0 pin value.