o  client data size not supportable

    The data size specified on opening the port cannot now be
    supported.

 o  incompatible communications mode

    The protocol cannot be operated because of an incompatible
    line.

    Argument:

    reason      Reason why the line is incompatible with the
                protocol.

                asynchronousThe  physical line does not support
                mode         asynchronous mode.

                crc not      The physical line does not support the
                supported    physical link for CRC operation.

                half-        The physical line needs to be in full-
                duplex       duplex mode.
                mode

 o  open physical port failed

    The open port failed at the Physical layer.

    Argument:

    reason   Reason why the open port failed.

             insufficient  A physical port cannot be created
             resources     due to a lack of system resources.

             invalid       An illegal data type or value was
             argument      supplied to the called routines.

             line not      The physical line has already been
             available     assigned to another port.

             no such       A physical line having the specified
             physical      name does not exist.
             line