7 years, 6 months ago.

Nucleo L476RG Virtual COM Port Wrong Driver

I'm having some problems the Nucleo virtual COM port. Initially, for some reason, I had STMicroelectronics VCP v1.0.0.0 installed on my 64-bit Windows 10 machine. I was communicating to my nucleo board through the usb com port, and the COM port would spontaneously drop. I would have to close and re-open the COM port in order to start communication.

I have a colleague who doesn't have this problem, and he has v1.1.0.0 on his machine. Thinking that this might be due to the old driver, I attempted to install the latest driver I could find, v1.4.0. After running the installer, windows device manager still indicated that it was using v1.0.0.0. Even after machine restarts, reconnecting the USB cable, The driver that the Nucleo board was using for the virtual com port was still v1.0.0.0.

Feeling desperate, I tried to uninstall the device in an attempt to completely remove v1.0.0.0 from my machine. Then, being careful to keep the Nucleo board disconnected, running v1.4.0 setup again. Now, when I plug the Nucleo in, it uses some Microsoft generic driver dating back to 2006 for a virtual COM port. The COM port still randomly drops.

I'm not sure if the COM port dropping is due to the driver or to hardware, but I would at least like to be able to use the latest driver to be sure. And my PC is refusing to use the latest driver.

1 Answer

7 years, 6 months ago.

Hi. Try the following -> connect your Nucleo board to your PC and allow whatever driver to map to the hardware. Once the driver is installed and the pop-ups settle down -> right mouse click and select to UNINSTALL the driver -> now you should also be presented with a checkbox to allow you to DELETE the same mapped driver. Go ahead and select the checkbox. Remove the USB widget and dock again to check on the status. Once you do this process enough times, you should be able to remove and delete the low level INF files that are causing this pairing of the hardware to the kernel mode device driver. After the above, you should be able to install the ST VCP. On the dropping, is your USB cable solid and of quality ? Consider to test another USB cable to rule out the quality of the cable. Also your colleague is on Win 10 ?

http://forum.espruino.com/conversations/290299/

Interesting post here suggesting to test the USB cable on a USB 2.0 port (non-blue plastic insulator - try a black insulator USB port).

https://developer.mbed.org/questions/3017/STM32F401RE-Nucleo-Virtual-COM-Port-is-n/

Believe this version of the VCP should be suitable for your use and is more current:

http://www.st.com/content/st_com/en/products/development-tools/software-development-tools/stm32-software-development-tools/stm32-utilities/stsw-stm32102.html

Hey Sanjiv

Thanks for your replay. Unfortunately, it didn't get me very far. Under Device Manager, I can uninstall the device, but the next time I plug in the Nucleo board, it always loads a Microsoft driver dated 6/21/2006, v10.0.15063.0. I am not given an option or checkbox to uninstall the driver. I have seen this issue across different USB cables and going into different USB ports on the PC. My colleague is using Win 7. He noticed that the documents for the Nucleo don't seem to include support for Win 10. I am able to get the correct drivers loaded for a separate windows 7 laptop and don't see any issues with the VCP.

It would be much more convenient for me if I could get the Nucleo to work reliably with my Widnows 10 PC. I don't know if the operating system really is to blame or the driver. But it's really frustrating that I can't get Windows to use the right driver. I'm really not certain if I can blame the operating system, or the driver for the issue.

posted by Chris Novak 17 May 2017

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Your issue may be related to this posted fault and resolution. Perform the same upgrade and test again. Please post your results.

https://developer.mbed.org/questions/78085/STs-USBSerial-Issue-on-Windows-Disco-L47/

posted by Sanjiv Bhatia 19 May 2017