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Error - Unknown USB Device(Device Descriptor Request Failed)

ORana.1
Associate II

Hello

I am Developing the Code for USB CDC Device communication to the STM32L496AGI3 Custom board.

This USB Device Code runs fine in the Ubuntu Based System.

in that USB Com port detected very well.

But When I plug in the USB cable of the Board to the Windows 10 PC ,every time its shows unknown USB Device.

So Please give Solution for this issue.

6 REPLIES 6
TDK
Guru

Use wireshark or similar USB analyzer to identify the issue.

If you feel a post has answered your question, please click "Accept as Solution".
ORana.1
Associate II

0693W00000JPgalQAD.pngHello TDK,

I downloaded the wireshark analyzer but when i opening that in the main window list its not showing the usbCAP1 for capturing the packet

can you suggest me the steps for that or have any method to add that.

Did you install PCAP?
https://desowin.org/usbpcap/
Could also try "USB Monitor Pro" which worked for me.
If you feel a post has answered your question, please click "Accept as Solution".
ORana.1
Associate II

Hello TDK,

I am installing USB Monitoring(Device Monitoring Studio) can you please guide how to detect and fix the issue?

TDK
Guru

USB is a somewhat complicated protocol and it will take some debugging skill to determine what is wrong as well as some understanding of what the correct communication should be. I'm not sure I can debug your issue with the provided information, even if that was my job.

https://www.usbmadesimple.co.uk/

I would suggest taking a capture of the USB communication upon plugging in the device and comparing the expected protocol. The ST USB library is not terribly robust and there are issues with it as discussed online in many different locations. Depending on the version you are using, some of these issues may or may not be fixed.

There are ST examples for most peripherals, including CDC, which can be used to verify the hardware is functioning as well as a comparison against your own code.

If you feel a post has answered your question, please click "Accept as Solution".
ORana.1
Associate II

Hello TDK,

in One windows 10 PC version:1909 i am detecting the stm32 virtual com port but in second Windows 10 PC version :21H1,21H2 its not detecting.

So is there problem of OS version?