I'm using STM32L073RZ on my own board, and I am trying to program USB device (I tried virtual COM and HID, separately). But after plugging into PC it is detected (after a while) with "Unknown device (device descriptor request failed)" error in windows 1

[MRAFI.376]

Electrically (PCB):

I think that PCB is not an error here - I just have D+ and D- short tracks from the connector to the uC and that's all.

I have a pull-up 1.5k (I tried with and without it), but it is not even needed in STM32. I have check connection and a cable and I'm certain it connects.

Code:

I'm using HAL and STM32CubeMx generated code merged with my project

is this a software or hardware issue?

[Tesla DeLorean]

If it is a part supporting the ROM System Loader, and USB DFU, try pulling BOOT0 high, and reset/connect as a DFU device, should report "STM32 in DFU Mode" or somesuch.

On your board make sure you're using a crystal oscillator, that it starts, and the speed and HSE_VALUE are consistent.

Try also on known hardware like an EVAL board, or LORA-DISCO board

[MRAFI.376]

Thank you for your replay

I just try STM32 DFU USB class but it not working in STM32L073RZ nucleo board

why its not working in this development board?. I am using an external crystal oscillator of 8 MHz later i change usb clock configuration to 48 MHz internal USB clock but its not working

Later I use to STM32Cube L0 example code (USB CDC standalone application code for STM32L073Z eval board code) it is not working nucleo board

is this a Hardware or Software issue?

how do i solve this ?

I am using STM workbench as IDE

in Nucleo Boad VBUS is already connected to 3.3v through 0 ohm resistance ,I am not using any series resistance with D+ and D- line is there any issue with this Hardware configuration

I am also tried Ubuntu 18 os result is same as in windows OS

is there any Reference of USB hardware specifically for STM32L073Z nucleo development board

[DCull.1]

Hi,

I am also using the NUCLEO-L073RZ eval board and I am experiencing similar problems.

I create a USB CDC project with CubeMX and have connected a USB cable to pins 12 ,14 and 20 GND on the morpho connector CN10.

I also have not connected VBUS from the USB cable.

When I plug the USB cable in I get Device Descriptor Request Failedon my PC ( win 10 ).

I have ordered a different eval board (STM32L073Z-EVAL ) that has built in USB connector and a specific project for USB CDC on the peripheral, not through the ST-LINK USB. ( I hope !! ). Going to try to get this going then compare to L073RZ.

Regards.