Hey im currently trying to use the CubeIDE to create a simple USB COM Communication.
I used the following settings
System Core
- RCC: HSE = Crystal\Ceramic Resonator
Connectivity
- USB_OTG_FS
- Mode: Device_Only
- VBUS: Disable
- No Activate_SOF
- Speed: Fullspeed 12Mbits
Middleware:
- USB_DEVICE_M7: Class for FS IP = Virtual Com Port
Clock Config
The NVIC1 USB on the go fs global interrupt also seems to be set.
When i run the generated code however, windows gives me the warning, that the usb-device is not recognized.
In the device manager it says Code 43, error requesting the USD_device descriptors.
Does anyone have an Idea, why this error is occuring? I think my clock or general setup could be the problem, but I sadly haven't found the issue yet.
Any help is greatly appreciated
Literally 10 Minutes after this post, i got it working.
I changed the usb clock from PPLL3Q to RC48.
Now the new question: Why is it working now? Configuring clocks is quiet new to me and I don't realy get the difference between the to options i tried.
The first one (which wasn't working) also seemed to provide 48Mhz, why is the second one working but not the first.
Sorry if this seems obvious to you, but i dont get it.
> I changed the usb clock from PPLL3Q to RC48.
USB needs a 48 MHz clock. PLL3Q is 48.011364 MHz per your screenshot, which is not 48 MHz so it doesn't work.
HSE on that board is a 8 MHz bypass signals coming from the ST-Link chip by default. Did you modify solder bridges to use the 25 MHz crystal instead?
