> 2.5 | Limitation of Virtual Ports

> Flow control can be set to RTS/CTS or DSR/DTR. XON/XOFF flow control is not supported. Hardware flow control on the virtual COM ports is handled internally by the Multiplexer Protocol.
> The WinMux driver handles neither modem nor serenum IO-control requests.
> The WinMux driver supports only 8 data bits, no parity, and one stop bit.
> The function IOCTL_SERIAL_XOFF_COUNTER is not supported.
> The following functions return “success”, but have no effect at all:

> • | IOCTL_SERIAL_SET_BREAK_ON

> • | IOCTL_SERIAL_SET_BREAK_OFF

> • | IOCTL_SERIAL_SET_XOFF

> • | IOCTL_SERIAL_SET_XON

> • | IOCTL_SERIAL_RESET_DEVICE

> Virtual ports accept any baud rate, though the changed setting will be ignored. Calling the function Open() to a virtual port can take up to 40 seconds. It fails if the module is not connected.