o  bisync code
    Default: EBCDIC        Value: ASCII or EBCDIC
    Character code to be used on the link. This characteristic is
    supported only when the characteristic protocol is set to one of
    the following: bisync, chips, genbyte, or swift. You can modify
    this characteristic only when the entity is disabled.
 o  bits per character
    Default: 8             Value: 5-8
    Number of bits in each character. This characteristic is
    supported only when the characteristic protocol is set to
    genbyte. You can modify this characteristic only when the entity
    is disabled.
 o  buffer size
    Default: 512           Value: 0-65535
    Size, in octets, of each receive buffer for the link. You can
    modify this characteristic only when the entity is disabled.
    Also, you can only increase the characteristic value.
 o  control mode
    Default: point to      Value: See description
    point
    Control mode in which the link is to operate. The value of this
    characteristic derives from the point to point argument to the
    create command.
    multipoint master
    multipoint
    tributary
    point to point
    You cannot modify this characteristic.
 o  crc type
    Default: See           Value: See description
    description
    CRC type used on the link.
    AUTO_DIN
    CRC_16
    CRC_CCITT
    CRC_CCITT0
    LRC_EVEN
    LRC_ODD
    LRC_VRC_
    EVEN
    LRC_VRC_
    ODD
    NONE
    The default value depends on the protocol.
    BISYNC   CRC_16
    CHIPS    LRC_EVEN
    DDCMP    CRC_16
    GENBYTE  NONE
    HDLC     CRC_CCITT
    SDLC     CRC_CCITT
    SWIFT    CRC_16
    genbyte crc checking is done in the genbyte framing routine.
 o  framing timer
    Default: 25            Value: 10-1000
    Maximum length of time, in milliseconds, to wait for the next
    character to arrive. This characteristic is supported only when
    the characteristic protocol is set to genbyte.
 o  initial state one
    Default: 0             Value: See description
    First 32 bits of state information. This characteristic is
    supported only when the characteristic protocol is set to
    genbyte. You can modify this characteristic only when the entity
    is disabled.
 o  initial state two
    Default: 0             Value: See description
    Last 32 bits of state information. This characteristic is
    supported only when the characteristic protocol is set to
    genbyte. You can modify this characteristic only when the entity
    is disabled.
 o  local station address
    Default: 255           Value: 0-255
    Address of the local station. The default value means that only
    broadcast messages are accepted. The interpretation of this
    characteristic is controlled by the value of the characteristic
    match station address.
    This attribute is supported only if the characteristic protocol
    is set to sdlc. You can modify this characteristic only when the
    entity is disabled.
 o  match station address
    Default: False         Value: True or False
    Specifies whether the value of the characteristic local station
    address is to be interpreted as a valid address. This attribute
    is supported only if the characteristic protocol is set to
    sdlc. You can modify this characteristic only when the entity
    is disabled.
 o  number of buffers
    Default: 4             Value: 0-255
    Number of receive buffers reserved for the link. You can modify
    this characteristic only when the entity is disabled. Also, you
    can only increase the characteristic value.
 o  physical line
    Default: None          Value: Local entity name
    Name of the Physical layer line entity on which the link
    operates. You must provide a value for this characteristic before
    you enable the link. You can modify this characteristic only when
    the entity is disabled.
 o  protocol
    Framing protocol used on the line. The value of this
    characteristic derives from the protocol argument to the create
    command. You cannot modify this characteristic.
    bisync     hdlc
    chips      sdlc
    ddcmp      swift
    genbyte
 o  sync character
    Default: See           Value: 0-FF
    description
    Hexadecimal code of the sync character to be used on the link.
    The default value depends on the value of the characteristic
    protocol, as follows:
    bisync   32
    chips    32
    ddcmp    96
    genbyte  32
    swift    32
    This attribute is supported only if the characteristic protocol
    is set to bisync, chips, ddcmp, genbyte, or swift. You can modify
    this characteristic only when the entity is disabled.
 o  sync count
    Default: 4             Value: 0-255
    Number of sync characters that precede each message. This
    attribute is supported only if the characteristic protocol is
    set to bisync, chips, ddcmp, genbyte, or swift. You can modify
    this characteristic only when the entity is disabled.