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For a factory new STM32F401CE, does the HSE oscillator run before loading any code? 

Question asked by John Griessen on Mar 22, 2018
Latest reply on Mar 23, 2018 by John Griessen

I'm wanting pointers to how to debug a new platform design.  Will the internal oscillator allow loading code via boot0 and the USB port?

 

Here's the schematic and layout:  

culture_shock/pyflex_f401.sch.png at master · kanzure/culture_shock · GitHub 

culture_shock/pyflex_f401_boost.sch.png at master · kanzure/culture_shock · GitHub 

culture_shock/pyflex_f401.assy.png at master · kanzure/culture_shock · GitHub 

I put a guard ring around the crystals and caps, and kept them short ans symmetric.

When 3.0V applied, I get no oscillations at the HSE output or LSE output measured with an active probe with 3pF loading.

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