STM32 USB simulates CH341.（STM32F103.PD0 connect 1.5k then connect D+)
- ST's USB virtual com port demo's driver have no signature(difficult to install).
- The driver of CH341 is easy to install.
- I feel bored.
It's not very difficult to develop. I just referred to the linux usb driver of ch341. You can simulate other chips in the same way.