STM32 USB HID + VCP not working but DFU is

[dave_mcc]

I am using the STM32L433 MCU and both the HID and VCP interfaces are not working even though the DFU is.

I am simply using the STM32CubeMX software to generate a standard default USB Setup but I keep getting the same Windows USB Error "USB Device Not Recognised" which is the "Device Descriptor request failed".

My hardware is a custom design and believe that I have the correct differential impedance or the DFU would not have worked.

 

VBUS is at 3.3V (<4V)

D+/D- traces > 2 inches but differential impedance has been matched to 90 Ohms using Altium.

I have a 12MHZ Crystal, the MCU can run Crystal-less.

USB is 48MHz but runs from RC, also used PLLSA1 from HSE.

STM32CubeIDE v2.1.1

MX_USB_DEVICE_Init() called.

 

If the DFU is working then why not the other USB Interfaces?

[FBL]

Hi @dave_mcc 

Did you refer to example firmware provided ? Did you follow this article to configure your PMA?

[dave_mcc]

I have followed that tutorial and all appears well.

The initialisation functions in USB_Device_Init() throw up no errors but does not continue to enumerate the device and send the descriptors.

 

[Andrew Neil]

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@dave_mcc wrote:

My hardware is a custom design 

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So please show the schematic.

How to write your question to maximize your chances to find a solution

 

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@dave_mcc wrote:

If the DFU is working then why not the other USB Interfaces?

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By "DFU", do you mean the USB System Bootloader ?

If so that  suggests that your hardware is OK - so the problem must be in your software.