UCHAR
CpReadLsr(
      PCPPORT Port,
      UCHAR waiting
  );

    Routine Description:

        Read LSR byte from specified port.  If HAL owns port & display
        it will also cause a debug status to be kept up to date.

        Handles entering & exiting modem control mode for debugger.

    Arguments:

        Port - Address of CPPORT

    Returns:

        Byte read from port