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STM32F4-Discovery USB-CDC VCP - Device Enumeration Fails

Question asked by willer.alexander on Apr 28, 2014
Latest reply on May 1, 2014 by sung.chen_chung
Hello to everybody,

using the USB-Device example for the STM324xG_EVAL (CDC-Standalone) I tried to get USB up and running on the STM32F4-Discovery-Board. The example is taken from the latest version of the STM32Cube firmware package.

My problem is, that I had no success getting USB to work correctly. All I get is a error message (Windows) saying "Enumeration of device failed".

Up to now, I already verified the system clock to be correct by toggling a GPIO pin in the SysTick ISR. The pin state toggles every 1 ms, which matches the required SysTick interval.

Also, I checked the preprocessor definitions, currently the following are defined:
  • STM32F407xx
  • HSE_VALUE=8000000
  • HSI_VALUE=16000000

I have attached my main.c and main.h file, and also a screenshot of the CrossStudio project explorer.

My goal is to have a communication channel for µC <-> PC and vice versa - is the CDC-VCP example a good starting point?

What could be the cause of my problem? I already investigated this for many hours, but without any success.

If you need more information, please don't hesitate to ask.

Thanks in advance!

Alexander W.