Лоадером пишут в ОЗУ, потом перезапускают и бутятся оттуда. With multiple conversations with the ST micro people you can't protect the FLASH from access EXCEPT FROM JTAG ACCESS. RAM will have complete access to the internal FLASH, top to bottom. I have proven this with my unit.
Do not be fooled - this product does not protect the internal FLASH from reads from any internal RAM or any RAM attached to the product. It can be protected from reads from the JTAG port ONLY.
https://my.st.com/ …C17E¤tviews=5174