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.

The STSW-STM32102 software package contains four installation files based on the various versions of the Microsoft ® operating system. OS versions prior to Windows ® 7 are compatible with the Windows ® 7 installations included in the package. Starting from Windows ® 10, the STSW-STM32102 driver is no more adequate and the usage of the native inbox driver is recommended. Virtual COM Port Driver is typically installed in the C: Program Files (x86) STMicroelectronics Software Virtual COM Port Driver folder, but this location may differ a lot depending on the user's choice when installing the application.

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.)

Stm32

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.

Stm32 Virtual Com Port Driver Windows 8.1Stm32 driver usb windows 10

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

Stmicroelectronics Virtual Com Port Driver Windows 8.1

Good luck.