Unable to start USB from STCubeIDE

Adding the USB console with a buffer so I can perform printf before the console is open was very usefully as I instantly detect that it’s huge differences between starting the device from the IDE on debug mode or on its own.

These things are a bit annoying, but they can be handled if your aware of them. USB start from IDE if I restart the computer, but after a while it stop working. If I start the device outside the IDE I have no problem. I believe the issue is the PC/IDE and not the device.

STCubeIDE promote usage of Debug, meaning your start in single step mode and I know from other IDE’s that this sometimes can be a bit funny. I only use this to verify init sequences as single-step is very intrusive in a multi-threaded app. So the console is very valuable as it instantly tells you what is going on and give you a capability to log from the device at high speed since this is USB. STCubeIDE have a more hidden support for starting the device differently so I will set this up later. For now it is workable to restart the device by plugging USB cable in/out.

I am not sure USB is of much usage in real use on a control system, but it is very handy for debugging, downloading new firmware (once I get bootloader) and maintenance/config tasks. I am however depending on one feature – I need the MCU main feed to be 5V only and very separate from motor/pwm PSU’s. This enables me to power the MCU through the USB. I realize I need to review my boards on this to ensure this is safe. In fact, I am considering removing external PSU feeds for 5V and only use the RPI bus, meaning you either feed USB power to one device or add a PSU board to the stack.


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