CDC function added but no any com port shown

[Treacy Yao]

I want to add CDC function. I use the STM32F103RB NUCLEO to add this function. But when I running my application, and insert USB to PC, no COM port shown in PC. I generate the code from cube and I don't know where is the problem. I test WIN10 and WIN7 PC, both are no any port. I have install the related driver in win7

[Treacy Yao]

I use "BUS Hound" tool to analyze the data, find "low-speed dvice attached to this port". I think this is the cause for "device descriptor request failed". But I think I have configured "full-speed" in my code. Why

[Treacy Yao]

I use "BUS Hound" tool to analyze the data, find "low-speed dvice attached to this port". I think this is the cause for "device descriptor request failed". But I think I have configured "full-speed" in my code. Why

[Treacy Yao]

New update. full speed is OK now. Another problem shown in port "Port Reset Failed". With Bus hound data, I can see data stopped when CLEAR_FEATURE(PORT_ENABLE) step. Please see my BUS hound scratched data.

[Treacy Yao]

Could you give me your code?

[GSome]

My code is for a F303 chip and it is for using as a 4 channel oscilloscope so it would not run on your system.

I ran some tests on mine. My program communicates with a program on a windows computer.

With the setup I have with pullup resistor connected to PortB8 the program runs ok.

If I press the reset button (Black button) on the nucleo this signal goes low briefly then transmission from the pc stars in a steady stream but my nucleo program only sends data on command

If I connect pullup resistor direct to 3.3 volt line and press reset I don't see any pull down of this line and running pc program windows gives me an error device attached is not working.

If I then unplug the pullup resistor, then plug into ground, then unplug and plug back into 3.3 vols again the pc program starts working again.

I am no usb cdc expert but I assume means the pc sees voltage change on pin so it sends command to device to send descriptor. Device responds with descriptor and all is ok

An other method I found was to unplug and then replug the primary usb connector (the white connector in my picture) as this also drives voltage low which reprogramming or pressing rest does not do.

Hope this helps

George