Hi!
I'm planning on building an LED-Controller with WS2812B leds and an Arduino Nano for my PC Case. I want to communicate with the pc via Serial communication to a C# client software running on the PC.
I want to place the Arduino in the back side of my PC.
Is it possible to do Serial communication from the Arduino directly to the USB/COM Ports of the motherboard?
As in bypassing the connectors on the outside of the case?
If your mainboard is a few years old it may have IDC connectors for USB and serial ports. Look up the model number on the web and download the user manual. Somewhere near the front of the manual will be a picture showing the locations of the connectors.
Modern boards tend to have everything integrated and may lack a real serial port so using the external USB ports will be your only option.
Some motherboards , even quite newish have com1 on the motherboard . Look at the board or the manual.
The voltage levels are Rs232 , so not compatible with the Arduino - you need to use a MAX232 level converter chip.
You can then connect the coms port on th Arduino to that.