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Tesla DeLoreanBest answer
Guru
November 6, 2022
Suggests the MCU is non-responsive.
Did you program it previously?
Does it work with STM32 Cube Programmer as a stand-alone application?
If you have the LDO/SMPS settings wrong you can block access to the STM32.
The trick then is to solder a jumper between BOOT0 (BT0) and VDD.
With BOOT0 HIGH remove ALL power and USB
Reapply power/connections.
Attempt to access via STM32 Cube Programmer.
If that succeeds, ERASE your code from the part.
Fix your code.
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