STM32 Virtual COM Port Issues

For some reason, the Virtual Com Port (VCP) drivers for STM32 chips were acting up and not properly enumerating a usable COM port on Windows when I was testing an STM32L476 chip.

I’m not sure if this is a chip-specific issue or if this problem shows up on more chips using the STM32Cube Hardware Abstraction Layer.

(Even after I installed Atollic TrueSTUDIO and the older STSW-LINK004 Windows utility, which I like better than the new STM32CubeProgrammer because it doesn’t require Java.)

The solution was to install an older Windows 8 VCP driver that they list on their website as part number STSW-STM32102.

The fun part is that the README file says “For Windows 10, use Microsoft inbox driver and not this package.“, which doesn’t do anything for me.

The 64-bit driver for Windows 8 works fine on Windows 10 and fixes the problem.

After installing the driver, the entry shows up in the installed programs.

And more importantly, the USB device enumerates correctly as a COM port in the Device Manager.

Good luck.

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