I need to test if I can get away with this simple circuit. The only challenge with CH340 is that it’s documentation in English is limited, so it’s a bit difficult to read up on all the pin options. But, I have seen others attempting this so will give it a try. This is CH340 as minimalist as possible with UART on one side and USB on the other.
The reason I like this is quite simple. We bought RS485 adapters for 1.- USD build on these some time back and now we simply don’t bother with anything else. They simply work to well. They always install correctly on Windows with no fuzz.