https://blog.faceutil.com/2017/05/16/%eb%ac%b4%eb%a3%8c-%ea%b0%80%ec%83%81-%ec%8b%9c%eb%a6%ac%ec%96%bc%ed%8f%ac%ed%8a%b8-%ec%97%90%eb%ae%ac%eb%a0%88%ec%9d%b4%ed%84%b0virtual-serial-ports-emulator-%d0%b2/