We had run our STM32F207 Hardware over night with a battery. Now the battery is empty and we can't flash the STM32F207 with Ulink Me (of course with proper powersupply).
Ulink says: Error: Flash Download failed - "Cortex-M3"
We can check the RDP register: the value is 0xff so we are in RDP Level 1.
We try to flash the STM32F207 with the " erase full chip"-Option but Full Chip Erase failed. If we try to flash an other STM32F207-Hardware this works fine.
So we tried to flash \Keil\ARM\Boards\Keil\MCBSTM32F200\Blinky with OPTs set to Level 0 but we can't flash it.
So we have 2 Questíons
How is it posible that the Level change form 0 to 1 without any line of code to do this? How can we disable the Read Out Protection with Ulink Me?
More likely a power/connectivity issue than one where Read Out Protection being engaged.
Use the STLink application to adjust the option bytes, returning you to level 0. This will implicitly erase internal flash.
For this, you need a STLink, AFAIK. Maybe you can use a cheap STM32F0 discovery as a programmer.
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