MTConnectError_1.6.xsd

<?xml version='1.0' encoding='UTF-8'?>
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<xs:schema xmlns:xs='http://www.w3.org/2001/XMLSchema' xmlns='urn:mtconnect.org:MTConnectError:1.6' xmlns:mt='urn:mtconnect.org:MTConnectError:1.6' targetNamespace='urn:mtconnect.org:MTConnectError:1.6' elementFormDefault='qualified' attributeFormDefault='unqualified' xmlns:vc='http://www.w3.org/2007/XMLSchema-versioning' vc:minVersion='1.1'>
  <xs:element name='MTConnectError' type='MTConnectErrorType'>
    <xs:annotation>
      <xs:documentation>
        It is the root XML element of an mtconnecterrors response document.
      </xs:documentation>
    </xs:annotation>
  </xs:element>
  <xs:simpleType name='SenderType'>
    <xs:annotation>
      <xs:documentation>
        The sender of the message
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='CreationTimeType'>
    <xs:annotation>
      <xs:documentation>
        The date and time the document was created
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:dateTime'/>
  </xs:simpleType>
  <xs:simpleType name='SequenceType'>
    <xs:annotation>
      <xs:documentation>
        A sequence number
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:integer'>
      <xs:minInclusive value='1'/>
      <xs:maxExclusive value='18446744073709551615'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='TestIndicatorType'>
    <xs:annotation>
      <xs:documentation>
        A debugging flag for testing.
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:boolean'/>
  </xs:simpleType>
  <xs:simpleType name='InstanceIdType'>
    <xs:annotation>
      <xs:documentation>
        The instance number of the agent, used for fault tolerance
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:integer'>
      <xs:minInclusive value='1'/>
      <xs:maxExclusive value='18446744073709551615'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='BufferSizeType'>
    <xs:annotation>
      <xs:documentation>
        The size of the agents buffer
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:integer'>
      <xs:minInclusive value='1'/>
      <xs:maxExclusive value='4294967295'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='TimestampType'>
    <xs:annotation>
      <xs:documentation>
        The time the sample was reported
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:dateTime'/>
  </xs:simpleType>
  <xs:simpleType name='OccurrenceTimeType'>
    <xs:annotation>
      <xs:documentation>
        The time a sample occurred
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:dateTime'/>
  </xs:simpleType>
  <xs:simpleType name='VersionType'>
    <xs:annotation>
      <xs:documentation>
        A version number
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:NMTOKEN'/>
  </xs:simpleType>
  <xs:simpleType name='NameType'>
    <xs:annotation>
      <xs:documentation>
        A short name for any element
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='UuidType'>
    <xs:annotation>
      <xs:documentation>
        A universally unique id that uniquely identifies the element for
        it&apos;s entire life
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='SerialNumberAttrType'>
    <xs:annotation>
      <xs:documentation>
        A serial number for a piece of equipment
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='ItemSourceType'>
    <xs:annotation>
      <xs:documentation>
        The measurement source
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='RateType'>
    <xs:annotation>
      <xs:documentation>
        A sample rate in milliseconds per sample
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:float'/>
  </xs:simpleType>
  <xs:simpleType name='ComponentIdType'>
    <xs:annotation>
      <xs:documentation>
        The id of the component (maps to the id from probe)
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:ID'/>
  </xs:simpleType>
  <xs:simpleType name='IDType'>
    <xs:annotation>
      <xs:documentation>
        An identifier
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:ID'/>
  </xs:simpleType>
  <xs:simpleType name='SignificantDigitsValueType'>
    <xs:annotation>
      <xs:documentation>
        The number significant digits
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:integer'/>
  </xs:simpleType>
  <xs:simpleType name='CompositionIdType'>
    <xs:annotation>
      <xs:documentation>
        The item&apos;s reference to the Device model composition
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:IDREF'/>
  </xs:simpleType>
  <xs:simpleType name='DurationTimeType'>
    <xs:annotation>
      <xs:documentation>
        A length of time in seconds
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:float'/>
  </xs:simpleType>
  <xs:simpleType name='RemovedType'>
    <xs:annotation>
      <xs:documentation>
        A flag indicating the item has been removed
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:boolean'/>
  </xs:simpleType>
  <xs:simpleType name='KeyType'>
    <xs:annotation>
      <xs:documentation>
        The key for adata set
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:NMTOKEN'/>
  </xs:simpleType>
  <xs:simpleType name='IdRefType'>
    <xs:annotation>
      <xs:documentation>
        A reference to an identifier
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:IDREF'/>
  </xs:simpleType>
  <xs:simpleType name='AssetIdType'>
    <xs:annotation>
      <xs:documentation>
        The unique id of the asset
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='AssetAttrTypeType'>
    <xs:annotation>
      <xs:documentation>
        An asset type
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='AssetBufferSizeType'>
    <xs:annotation>
      <xs:documentation>
        The maximum number of assets
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:integer'>
      <xs:minInclusive value='1'/>
      <xs:maxExclusive value='4294967295'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='AssetCountAttrType'>
    <xs:annotation>
      <xs:documentation>
        The number of assets
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:integer'>
      <xs:minInclusive value='0'/>
      <xs:maxExclusive value='4294967295'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='FloatListValueType'>
    <xs:annotation>
      <xs:documentation>
        Common floating point sample value
      </xs:documentation>
    </xs:annotation>
    <xs:list>
      <xs:simpleType>
        <xs:restriction base='xs:float'/>
      </xs:simpleType>
    </xs:list>
  </xs:simpleType>
  <xs:simpleType name='ThreeSpaceValueType'>
    <xs:annotation>
      <xs:documentation>
        A three dimensional value &apos;X Y Z&apos; or &apos;A B C&apos;
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='FloatListValueType'>
      <xs:maxLength value='3'/>
      <xs:minLength value='3'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DescriptionTextType'>
    <xs:annotation>
      <xs:documentation>
        A description
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='DataItemExtType'>
    <xs:annotation>
      <xs:documentation>
        An extension point for data item types
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:pattern value='[a-ln-z]:[A-Z_0-9]+'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemStatsExtType'>
    <xs:annotation>
      <xs:documentation>
        An extension point for data item statistics types
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:pattern value='[a-ln-z]:[A-Z_0-9]+'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemEnumTypeEnum'>
    <xs:annotation>
      <xs:documentation>
        The types of measurements available
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='ACTUATOR'>
        <xs:annotation>
          <xs:documentation>
            A mechanism for moving or controlling a mechanical part of a piece
            of equipment. It takes energy usually provided by air, electric
            current, or liquid and converts the energy into some kind of motion.
            
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ACCELERATION'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the rate of change of velocity.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ACCUMULATED_TIME'>
        <xs:annotation>
          <xs:documentation>
            The measurement of accumulated time for an activity or event.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AMPERAGE'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.6. Replaced by amperageac sample and
            amperagedc sample.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ANGLE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of angular position.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ANGULAR_ACCELERATION'>
        <xs:annotation>
          <xs:documentation>
            The measurement rate of change of angular velocity.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ANGULAR_VELOCITY'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the rate of change of angular position.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AXIS_FEEDRATE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the feedrate of a linear axis.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CLOCK_TIME'>
        <xs:annotation>
          <xs:documentation>
            The value provided by a timing device at a specific point in time.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CONCENTRATION'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the percentage of one component within a mixture
            of components
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CONDUCTIVITY'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the ability of a material to conduct electricity.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DISPLACEMENT'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the change in position of an object.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ELECTRICAL_ENERGY'>
        <xs:annotation>
          <xs:documentation>
            The measurement of electrical energy consumption by a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='EQUIPMENT_TIMER'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the amount of time a piece of equipment or a
            sub-part of a piece of equipment has performed specific activities.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FILL_LEVEL'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the amount of a substance remaining compared to
            the planned maximum amount of that substance.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FLOW'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the rate of flow of a fluid.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FREQUENCY'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the number of occurrences of a repeating event
            per unit time.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='GLOBAL_POSITION'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.1
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LENGTH'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the length of an object.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LEVEL'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.2. See filllevel sample
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LINEAR_FORCE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the push or pull introduced by an actuator or
            exerted on an object.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LOAD'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the actual versus the standard rating of a piece
            of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MASS'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the mass of an object(s) or an amount of
            material.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PATH_FEEDRATE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the feedrate for the axes, or a single axis,
            associated with a path component-a vector.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PATH_POSITION'>
        <xs:annotation>
          <xs:documentation>
            A measured or calculated position of a control point associated with
            a controller element, or path element if provided, of a piece of
            equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PH'>
        <xs:annotation>
          <xs:documentation>
            A measure of the acidity or alkalinity of a solution.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POSITION'>
        <xs:annotation>
          <xs:documentation>
            A measured or calculated position of a component element as reported
            by a piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POWER_FACTOR'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the ratio of real power flowing to a load to the
            apparent power in that AC circuit.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PRESSURE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of force per unit area exerted by a gas or liquid.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROCESS_TIMER'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the amount of time a piece of equipment has
            performed different types of activities associated with the process
            being performed at that piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RESISTANCE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the degree to which a substance opposes the
            passage of an electric current.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ROTARY_VELOCITY'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the rotational speed of a rotary axis.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SOUND_LEVEL'>
        <xs:annotation>
          <xs:documentation>
            The measurement of a sound level or sound pressure level relative to
            atmospheric pressure.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SPINDLE_SPEED'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.2. Replaced by rotaryvelocity sample
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='STRAIN'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the amount of deformation per unit length of an
            object when a load is applied.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TEMPERATURE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of temperature.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TENSION'>
        <xs:annotation>
          <xs:documentation>
            The measurement of a force that stretches or elongates an object.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TILT'>
        <xs:annotation>
          <xs:documentation>
            The measurement of angular displacement. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TORQUE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the turning force exerted on an object or by an
            object.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VELOCITY'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the rate of change of position of a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VISCOSITY'>
        <xs:annotation>
          <xs:documentation>
            The measurement of a fluids resistance to flow.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT_AMPERE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the apparent power in an electrical circuit,
            equal to the product of root-mean-square (RMS) voltage and RMS
            current (commonly referred to as VA).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT_AMPERE_REACTIVE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of reactive power in an AC electrical circuit
            (commonly referred to as VAR).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLTAGE'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.6. Replaced by voltageac sample and
            voltagedc sample.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WATTAGE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of power flowing through or dissipated by an
            electrical circuit or piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ACTIVE_AXES'>
        <xs:annotation>
          <xs:documentation>
            The set of axes currently associated with a path or controller
            structural element.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ACTUATOR_STATE'>
        <xs:annotation>
          <xs:documentation>
            Represents the operational state of an apparatus for moving or
            controlling a mechanism or system.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ALARM'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED: Replaced with condition category category data items in
            Version 1.1.0.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AVAILABILITY'>
        <xs:annotation>
          <xs:documentation>
            Represents the agent&apos;s ability to communicate with the data
            source.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AXIS_COUPLING'>
        <xs:annotation>
          <xs:documentation>
            Describes the way the axes will be associated to each other. This is
            used in conjunction with coupledaxes event to indicate the way they
            are interacting.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AXIS_FEEDRATE_OVERRIDE'>
        <xs:annotation>
          <xs:documentation>
            The value of a signal or calculation issued to adjust the feedrate
            of an individual linear type axis.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AXIS_INTERLOCK'>
        <xs:annotation>
          <xs:documentation>
            An indicator of the state of the axis lockout function when power
            has been removed and the axis is allowed to move freely.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AXIS_STATE'>
        <xs:annotation>
          <xs:documentation>
            An indicator of the controlled state of a linear or rotary component
            representing an axis.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='BLOCK'>
        <xs:annotation>
          <xs:documentation>
            The line of code or command being executed by a controller
            structural element.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='BLOCK_COUNT'>
        <xs:annotation>
          <xs:documentation>
            The total count of the number of blocks of program code that have
            been executed since execution started.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CHUCK_INTERLOCK'>
        <xs:annotation>
          <xs:documentation>
            An indication of the state of an interlock function or control logic
            state intended to prevent the associated chuck component from being
            operated.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CHUCK_STATE'>
        <xs:annotation>
          <xs:documentation>
            An indication of the operating state of a mechanism that holds a
            part or stock material during a manufacturing process. It may also
            represent a mechanism that holds any other mechanism in place within
            a piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CODE'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.1.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='COMPOSITION_STATE'>
        <xs:annotation>
          <xs:documentation>
            An indication of the operating condition of a mechanism represented
            by a composition type element.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CONTROLLER_MODE'>
        <xs:annotation>
          <xs:documentation>
            The current operating mode of the controller component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CONTROLLER_MODE_OVERRIDE'>
        <xs:annotation>
          <xs:documentation>
            A setting or operator selection that changes the behavior of a piece
            of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='COUPLED_AXES'>
        <xs:annotation>
          <xs:documentation>
            Refers to the set of associated axes.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DIRECTION'>
        <xs:annotation>
          <xs:documentation>
            The direction of motion.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DOOR_STATE'>
        <xs:annotation>
          <xs:documentation>
            The operational state of a door type component or composition
            element.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='EMERGENCY_STOP'>
        <xs:annotation>
          <xs:documentation>
            The current state of the emergency stop signal for a piece of
            equipment, controller path, or any other component or subsystem of a
            piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='END_OF_BAR'>
        <xs:annotation>
          <xs:documentation>
            An indication of whether the end of a piece of bar stock being feed
            by a bar feeder has been reached.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='EQUIPMENT_MODE'>
        <xs:annotation>
          <xs:documentation>
            An indication that a piece of equipment, or a sub-part of a piece of
            equipment, is performing specific types of activities.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='EXECUTION'>
        <xs:annotation>
          <xs:documentation>
            The execution status of the controller.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FUNCTIONAL_MODE'>
        <xs:annotation>
          <xs:documentation>
            The current intended production status of the device or component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='HARDNESS'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the hardness of a material.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INTERFACE_STATE'>
        <xs:annotation>
          <xs:documentation>
            An indication of the operational state of an interface component
            component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LINE'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.4.0.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LINE_LABEL'>
        <xs:annotation>
          <xs:documentation>
            An optional identifier for a block event of code in a program event.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LINE_NUMBER'>
        <xs:annotation>
          <xs:documentation>
            A reference to the position of a block of program code within a
            control program.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MATERIAL'>
        <xs:annotation>
          <xs:documentation>
            The identifier of a material used or consumed in the manufacturing
            process.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MESSAGE'>
        <xs:annotation>
          <xs:documentation>
            Any text string of information to be transferred from a piece of
            equipment to a client software application.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OPERATOR_ID'>
        <xs:annotation>
          <xs:documentation>
            The identifier of the person currently responsible for operating the
            piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PALLET_ID'>
        <xs:annotation>
          <xs:documentation>
            The identifier for a pallet.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PART_COUNT'>
        <xs:annotation>
          <xs:documentation>
            The count of parts produced.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PART_ID'>
        <xs:annotation>
          <xs:documentation>
            An identifier of a part in a manufacturing operation.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PART_NUMBER'>
        <xs:annotation>
          <xs:documentation>
            An identifier of a part or product moving through the manufacturing
            process. The valid data value must be a text string. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PATH_FEEDRATE_OVERRIDE'>
        <xs:annotation>
          <xs:documentation>
            The value of a signal or calculation issued to adjust the feedrate
            for the axes associated with a path component that may represent a
            single axis or the coordinated movement of multiple axes.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PATH_MODE'>
        <xs:annotation>
          <xs:documentation>
            Describes the operational relationship between a path structural
            element and another path structural element for pieces of equipment
            comprised of multiple logical groupings of controlled axes or other
            logical operations.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POWER_STATE'>
        <xs:annotation>
          <xs:documentation>
            The indication of the status of the source of energy for a
            structural element to allow it to perform its intended function or
            the state of an enabling signal providing permission for the
            structural element to perform its functions.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POWER_STATUS'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.1.0.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM'>
        <xs:annotation>
          <xs:documentation>
            The name of the logic or motion program being executed by the
            controller component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM_COMMENT'>
        <xs:annotation>
          <xs:documentation>
            A comment or non-executable statement in the control program. The
            valid data value must be a text string.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM_EDIT'>
        <xs:annotation>
          <xs:documentation>
            An indication of the status of the controller components program
            editing mode. On many controls, a program can be edited while
            another program is currently being executed.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM_EDIT_NAME'>
        <xs:annotation>
          <xs:documentation>
            The name of the program being edited. This is used in conjunction
            with programedit event when in active value state. The valid data
            value must be a text string.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM_HEADER'>
        <xs:annotation>
          <xs:documentation>
            The non-executable header section of the control program.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ROTARY_MODE'>
        <xs:annotation>
          <xs:documentation>
            The current operating mode for a rotary type axis.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ROTARY_VELOCITY_OVERRIDE'>
        <xs:annotation>
          <xs:documentation>
            The value of a command issued to adjust the programmed velocity for
            a rotary type axis. This command represents a percentage change to
            the velocity calculated by a logic or motion program or set by a
            switch for a rotary type axis.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SERIAL_NUMBER'>
        <xs:annotation>
          <xs:documentation>
            The serial number associated with a component, asset
            mtconnectassets, or device. The valid data value must be a text
            string.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SPINDLE_INTERLOCK'>
        <xs:annotation>
          <xs:documentation>
            An indication of the status of the spindle for a piece of equipment
            when power has been removed and it is free to rotate.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOOL_ASSET_ID'>
        <xs:annotation>
          <xs:documentation>
            The identifier of an individual tool asset.The valid data value must
            be a text string.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOOL_ID'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED in Version 1.2.0. See toolassetid event. The identifier
            of the tool currently in use for a given path.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOOL_NUMBER'>
        <xs:annotation>
          <xs:documentation>
            The identifier assigned by the controller component to a cutting
            tool when in use by a piece of equipment. The valid data value must
            be a text string.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOOL_OFFSET'>
        <xs:annotation>
          <xs:documentation>
            A reference to the tool offset variables applied to the active
            cutting tool associated with a path in a controller type component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='USER'>
        <xs:annotation>
          <xs:documentation>
            The identifier of the person currently responsible for operating the
            piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WIRE'>
        <xs:annotation>
          <xs:documentation>
            A string like piece or filament of relatively rigid or flexible
            material provided in a variety of diameters.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WORK_OFFSET'>
        <xs:annotation>
          <xs:documentation>
            A reference to the offset variables for a work piece or part
            associated with a path in a controller type component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WORKHOLDING_ID'>
        <xs:annotation>
          <xs:documentation>
            The identifier for the current workholding or part clamp in use by a
            piece of equipment. The valid data value must be a text string.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='COMMUNICATIONS'>
        <xs:annotation>
          <xs:documentation>
            An indication that the piece of equipment has experienced a
            communications failure.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DATA_RANGE'>
        <xs:annotation>
          <xs:documentation>
            An indication that the value of the data associated with a measured
            value or a calculation is outside of an expected range.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='HARDWARE'>
        <xs:annotation>
          <xs:documentation>
            An indication of a fault associated with the hardware subsystem of
            the structural element.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LOGIC_PROGRAM'>
        <xs:annotation>
          <xs:documentation>
            An indication that an error occurred in the logic program or
            programmable logic controller (PLC) associated with a piece of
            equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MOTION_PROGRAM'>
        <xs:annotation>
          <xs:documentation>
            An indication that an error occurred in the motion program
            associated with a piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SYSTEM'>
        <xs:annotation>
          <xs:documentation>
            A general purpose indication associated with an electronic component
            of a piece of equipment or a controller that represents a fault that
            is not associated with the operator, program, or hardware.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ASSET_CHANGED'>
        <xs:annotation>
          <xs:documentation>
            The value of the cdata for the event MUST be the assetid of the
            asset that has been added or changed. There will not be a separate
            message for new assets.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ASSET_REMOVED'>
        <xs:annotation>
          <xs:documentation>
            The value of the cdata for the event MUST be the assetid of the
            asset that has been removed. The asset will still be visible if
            requested with the includeremoved parameter as described in the
            protocol section. When assets are removed they are not moved to the
            beginning of the most recently modified list. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OPEN_DOOR'>
        <xs:annotation>
          <xs:documentation>
            Service to open a door. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CLOSE_DOOR'>
        <xs:annotation>
          <xs:documentation>
            Service to close a door.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OPEN_CHUCK'>
        <xs:annotation>
          <xs:documentation>
            Service to open a chuck. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CLOSE_CHUCK'>
        <xs:annotation>
          <xs:documentation>
            Service to close a chuck.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MATERIAL_FEED'>
        <xs:annotation>
          <xs:documentation>
            Service to advance material or feed product to a piece of equipment
            from a continuous or bulk source. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MATERIAL_CHANGE'>
        <xs:annotation>
          <xs:documentation>
            Service to change the type of material or product being loaded or
            fed to a piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MATERIAL_RETRACT'>
        <xs:annotation>
          <xs:documentation>
            Service to remove or retract material or product.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PART_CHANGE'>
        <xs:annotation>
          <xs:documentation>
            Service to change the part or product associated with a piece of
            equipment to a different part or product. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MATERIAL_LOAD'>
        <xs:annotation>
          <xs:documentation>
            Service to load a piece of material or product.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MATERIAL_UNLOAD'>
        <xs:annotation>
          <xs:documentation>
            Service to unload a piece of material or product.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLUME_SPATIAL'>
        <xs:annotation>
          <xs:documentation>
            The geometric volume of an object or container.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLUME_FLUID'>
        <xs:annotation>
          <xs:documentation>
            The fluid volume of an object or container.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CAPACITY_SPATIAL'>
        <xs:annotation>
          <xs:documentation>
            The geometric capacity of an object or container.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CAPACITY_FLUID'>
        <xs:annotation>
          <xs:documentation>
            The fluid capacity of an object or container.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DENSITY'>
        <xs:annotation>
          <xs:documentation>
            The volumetric mass of a material per unit volume of that material.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEPOSITION_VOLUME'>
        <xs:annotation>
          <xs:documentation>
            The spatial volume of material to be deposited in an additive
            manufacturing process.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEPOSITION_RATE_VOLUMETRIC'>
        <xs:annotation>
          <xs:documentation>
            The rate at which a spatial volume of material is deposited in an
            additive manufacturing process.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEPOSITION_ACCELERATION_VOLUMETRIC'>
        <xs:annotation>
          <xs:documentation>
            The rate of change in spatial volume of material deposited in an
            additive manufacturing process.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEPOSITION_MASS'>
        <xs:annotation>
          <xs:documentation>
            The mass of the material deposited in an additive manufacturing
            process.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEPOSITION_DENSITY'>
        <xs:annotation>
          <xs:documentation>
            The density of the material deposited in an additive manufacturing
            process per unit of volume.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROCESS_TIME'>
        <xs:annotation>
          <xs:documentation>
            The time and date associated with an activity or event. processtime
            event MUST be reported in ISO 8601 format.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DATE_CODE'>
        <xs:annotation>
          <xs:documentation>
            The time and date code associated with a material or other physical
            item. datecode event MUST be reported in ISO 8601 format.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MATERIAL_LAYER'>
        <xs:annotation>
          <xs:documentation>
            Identifies the layers of material applied to a part or product as
            part of an additive manufacturing process. The valid data value MUST
            be an integer.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WAIT_STATE'>
        <xs:annotation>
          <xs:documentation>
            An indication of the reason that execution event is reporting a
            value of wait. The valid data value MUST be poweringup,
            poweringdown, partload, partunload, toolload, toolunload,
            materialload event, materialunload event, secondaryprocess, pausing,
            or resuming.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PART_DETECT'>
        <xs:annotation>
          <xs:documentation>
            An indication designating whether a part or work piece has been
            detected or is present. The valid data value MUST be present or
            notpresent.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEVICE_UUID'>
        <xs:annotation>
          <xs:documentation>
            The identifier of another piece of equipment that is temporarily
            associated with a component of this piece of equipment to perform a
            particular function. The valid data value MUST be a NMTOKEN XML
            type.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CUTTING_SPEED'>
        <xs:annotation>
          <xs:documentation>
             The speed difference (relative velocity) between the cutting
            mechanism and the surface of the workpiece it is operating on.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PATH_FEEDRATE_PER_REVOLUTION'>
        <xs:annotation>
          <xs:documentation>
            The feedrate for the axes, or a single axis.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM_NEST_LEVEL'>
        <xs:annotation>
          <xs:documentation>
            An indication of the nesting level within a control program that is
            associated with the code or instructions that is currently being
            executed. If an Initial Value is not defined, the nesting level
            associated with the highest or initial nesting level of the program
            MUST default to zero (0). The value reported for programnestlevel
            event MUST be an integer.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM_LOCATION_TYPE'>
        <xs:annotation>
          <xs:documentation>
            Defines whether the logic or motion program defined by program event
            is being executed from the local memory of the controller or from an
            outside source. The valid data value MUST be local or external.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAM_LOCATION'>
        <xs:annotation>
          <xs:documentation>
            The Uniform Resource Identifier (URI) for the source file associated
            with program event.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOOL_GROUP'>
        <xs:annotation>
          <xs:documentation>
            An identifier for the tool group associated with a specific tool.
            Commonly used to designate spare tools.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VARIABLE'>
        <xs:annotation>
          <xs:documentation>
             A data value whose meaning may change over time due to changes in
            the operation of a piece of equipment or the process being executed
            on that piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AMPERAGE_AC'>
        <xs:annotation>
          <xs:documentation>
            The measurement of an electrical current that reverses direction at
            regular short intervals.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AMPERAGE_DC'>
        <xs:annotation>
          <xs:documentation>
            The measurement of an electric current flowing in one direction
            only.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLTAGE_AC'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the electrical potential between two points in an
            electrical circuit in which the current periodically reverses
            direction.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLTAGE_DC'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the electrical potential between two points in an
            electrical circuit in which the current is unidirectional.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='X_DIMENSION'>
        <xs:annotation>
          <xs:documentation>
            Measured dimension of an entity relative to the X direction of the
            referenced coordinate system.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='Y_DIMENSION'>
        <xs:annotation>
          <xs:documentation>
            Measured dimension of an entity relative to the Y direction of the
            referenced coordinate system.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='Z_DIMENSION'>
        <xs:annotation>
          <xs:documentation>
            Measured dimension of an entity relative to the Z direction of the
            referenced coordinate system.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DIAMETER'>
        <xs:annotation>
          <xs:documentation>
            The measured dimension of a diameter.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OPERATING_SYSTEM'>
        <xs:annotation>
          <xs:documentation>
            The Operating System of a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FIRMWARE'>
        <xs:annotation>
          <xs:documentation>
            The embedded software of a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='APPLICATION'>
        <xs:annotation>
          <xs:documentation>
            The application on a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LIBRARY'>
        <xs:annotation>
          <xs:documentation>
            The software library on a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='NETWORK'>
        <xs:annotation>
          <xs:documentation>
            Network details of a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ORIENTATION'>
        <xs:annotation>
          <xs:documentation>
            A measured or calculated orientation of a plane or vector relative
            to a cartesian coordinate system.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ROTATION'>
        <xs:annotation>
          <xs:documentation>
            A three space angular rotation relative to a coordinate system.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TRANSLATION'>
        <xs:annotation>
          <xs:documentation>
            A three space linear translation relative to a coordinate system.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CoordinateSystems'>
        <xs:annotation>
          <xs:documentation>
            It aggregates coordinatesystem new configurations for a component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='Specifications'>
        <xs:annotation>
          <xs:documentation>
            It aggregates specification elements describing the design
            characteristics for a piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WORLD'>
        <xs:annotation>
          <xs:documentation>
            stationary coordinate system referenced to earth, which is
            independent of the robot motion. Ref:ISO 9787:2013. For non-robotic
            devices, stationary coordinate system referenced to earth, which is
            independent of the motion of a piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='BASE'>
        <xs:annotation>
          <xs:documentation>
            coordinate system referenced to the base mounting surface. Ref:ISO
            9787:2013. A base mounting surface is a connection surface between
            the arm and its supporting structure. Ref:ISO 9787:2013. For
            non-robotic devices, it is the connection surface between the device
            and its supporting structure.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OBJECT'>
        <xs:annotation>
          <xs:documentation>
            coordinate system referenced to the object. Ref:ISO 9787:2013
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TASK'>
        <xs:annotation>
          <xs:documentation>
            coordinate system referenced to the site of the task. Ref:ISO
            9787:2013
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MECHANICAL_INTERFACE'>
        <xs:annotation>
          <xs:documentation>
            coordinate system referenced to the mechanical interface. Ref:ISO
            9787:2013
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOOL'>
        <xs:annotation>
          <xs:documentation>
            coordinate system referenced to the tool or to the end effector
            attached to the mechanical interface. Ref:ISO 9787:2013
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MOBILE_PLATFORM'>
        <xs:annotation>
          <xs:documentation>
            coordinate system referenced to one of the components of a mobile
            platform. Ref:ISO 8373:2012
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CAMERA'>
        <xs:annotation>
          <xs:documentation>
            coordinate system referenced to the sensor which monitors the site
            of the task. Ref:ISO 9787:2013
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='HUMIDITY_RELATIVE'>
        <xs:annotation>
          <xs:documentation>
            The amount of water vapor present expressed as a percent to reach
            saturation at the same temperature.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='HUMIDITY_ABSOLUTE'>
        <xs:annotation>
          <xs:documentation>
            The amount of water vapor expressed in grams per cubic meter.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='HUMIDITY_SPECIFIC'>
        <xs:annotation>
          <xs:documentation>
            The ratio of the water vapor present over the total weight of the
            water vapor and air present expressed as a percent.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VARIABLE'>
        <xs:annotation>
          <xs:documentation>
            A user variable
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemEnumType'>
    <xs:annotation>
      <xs:documentation>
        The types of measurements available
      </xs:documentation>
    </xs:annotation>
    <xs:union memberTypes='DataItemEnumTypeEnum DataItemExtType'/>
  </xs:simpleType>
  <xs:simpleType name='DataItemSubEnumTypeEnum'>
    <xs:annotation>
      <xs:documentation>
        The sub-types for a measurement
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='ACTUAL'>
        <xs:annotation>
          <xs:documentation>
            The measured value of the data item type given by a sensor or
            encoder.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MAXIMUM'>
        <xs:annotation>
          <xs:documentation>
            Maximum value of a data entity or attribute.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MINIMUM'>
        <xs:annotation>
          <xs:documentation>
            The minimum value of a data entity or attribute.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DIRECT'>
        <xs:annotation>
          <xs:documentation>
            The measurement of DC current or voltage.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TARGET'>
        <xs:annotation>
          <xs:documentation>
            The desired measure or count for a data item value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='COMMANDED'>
        <xs:annotation>
          <xs:documentation>
            A value specified by the controller type component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OVERRIDE'>
        <xs:annotation>
          <xs:documentation>
            DEPRECATED: The operators overridden value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROGRAMMED'>
        <xs:annotation>
          <xs:documentation>
            The value of a signal or calculation specified by a logic or motion
            program or set by a switch.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RAPID'>
        <xs:annotation>
          <xs:documentation>
            The value of a signal or calculation issued to adjust the feedrate
            of a component or composition that is operating in a rapid
            positioning mode.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WORKING'>
        <xs:annotation>
          <xs:documentation>
            A piece of equipment performing any activity, the equipment is
            active and performing a function under load or not.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='STANDARD'>
        <xs:annotation>
          <xs:documentation>
            The standard or original length of an object.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='USEABLE'>
        <xs:annotation>
          <xs:documentation>
            The remaining useable length of an object.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROBE'>
        <xs:annotation>
          <xs:documentation>
            The position provided by a measurement probe.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PROCESS'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the time from the beginning of production of a
            part or product on a piece of equipment until the time that
            production is complete for that part or product on that piece of
            equipment. This includes the time that the piece of equipment is
            running, producing parts or products, or in the process of producing
            parts.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='A_SCALE'>
        <xs:annotation>
          <xs:documentation>
            A Scale weighting factor. This is the default weighting factor if no
            factor is specified
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='B_SCALE'>
        <xs:annotation>
          <xs:documentation>
            B Scale weighting factor
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='C_SCALE'>
        <xs:annotation>
          <xs:documentation>
            C Scale weighting factor
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='D_SCALE'>
        <xs:annotation>
          <xs:documentation>
            D Scale weighting factor
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='NO_SCALE'>
        <xs:annotation>
          <xs:documentation>
            No weighting factor on the frequency scale
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ALTERNATING'>
        <xs:annotation>
          <xs:documentation>
            The measurement of alternating voltage or current. If not specified
            further in statistic, defaults to RMS voltage. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MANUAL_UNCLAMP'>
        <xs:annotation>
          <xs:documentation>
            An indication of the state of an operator controlled interlock that
            can inhibit the ability to initiate an unclamp action of an
            electronically controlled chuck. The valid data value must be active
            value or inactive value. When manualunclamp subtype is active value,
            it is expected that a chuck cannot be unclamped until manualunclamp
            subtype is set to inactive value. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ACTION'>
        <xs:annotation>
          <xs:documentation>
            An indication of the operating state of a mechanism represented by a
            composition type component. The operating state indicates whether
            the composition element is activated or disabled. The valid data
            value must be active value or inactive value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LATERAL'>
        <xs:annotation>
          <xs:documentation>
            An indication of the position of a mechanism that may move in a
            lateral direction. The mechanism is represented by a composition
            type component. The position information indicates whether the
            composition element is positioned to the right, to the left, or is
            in transition. The valid data value must be right value, left value,
            or transitioning value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MOTION'>
        <xs:annotation>
          <xs:documentation>
            An indication of the open or closed state of a mechanism. The
            mechanism is represented by a composition type component. The
            operating state indicates whether the state of the composition
            element is open, closed, or unlatched. The valid data value must be
            open value, unlatched value, or closed value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SWITCHED'>
        <xs:annotation>
          <xs:documentation>
            An indication of the activation state of a mechanism represented by
            a composition type component. The activation state indicates whether
            the composition element is activated or not. The valid data value
            must be on value or off value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VERTICAL'>
        <xs:annotation>
          <xs:documentation>
            An indication of the position of a mechanism that may move in a
            vertical direction. The mechanism is represented by a composition
            type component. The position information indicates whether the
            composition element is positioned to the top, to the bottom, or is
            in transition. The valid data value must be up value, down value, or
            transitioning value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DRY_RUN'>
        <xs:annotation>
          <xs:documentation>
            A setting or operator selection used to execute a test mode to
            confirm the execution of machine functions. The valid data value
            must be on value or off value. When dryrun subtype is on value, the
            equipment performs all of its normal functions, except no part or
            product is produced. If the equipment has a spindle, spindle
            operation is suspended.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MACHINE_AXIS_LOCK'>
        <xs:annotation>
          <xs:documentation>
            A setting or operator selection that changes the behavior of the
            controller on a piece of equipment. The valid data value must be on
            value or off value. When machineaxislock subtype is on value,
            program execution continues normally, but no equipment motion occurs
            
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OPTIONAL_STOP'>
        <xs:annotation>
          <xs:documentation>
            A setting or operator selection that changes the behavior of the
            controller on a piece of equipment. The valid data value must be on
            value or off value. The program execution is stopped after a
            specific program block is executed when optionalstop subtype is on
            value. In the case of a G-Code program, a program block event
            containing a M01 code designates the command for an optionalstop
            subtype. execution event must change to optionalstop subtype after a
            program block specifying an optional stop is executed and the
            optionalstop subtype selection is on value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SINGLE_BLOCK'>
        <xs:annotation>
          <xs:documentation>
            A setting or operator selection that changes the behavior of the
            controller on a piece of equipment. The valid data value must be on
            value or off value. Program execution is paused after each block
            event of code is executed when singleblock subtype is on value. When
            singleblock subtype is on value, execution event must change to
            interrupted value after completion of each block event of code. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOOL_CHANGE_STOP'>
        <xs:annotation>
          <xs:documentation>
            A setting or operator selection that changes the behavior of the
            controller on a piece of equipment. The valid data value must be on
            value or off value. Program execution is paused when a command is
            executed requesting a cutting tool to be changed. execution event
            must change to interrupted value after completion of the command
            requesting a cutting tool to be changed and toolchangestop subtype
            is on value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LINEAR'>
        <xs:annotation>
          <xs:documentation>
            The direction of motion of a linear motion.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ROTARY'>
        <xs:annotation>
          <xs:documentation>
            The rotational direction of a rotary motion using the right hand
            rule convention. The valid data value must be clockwise value or
            counterclockwise value.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AUXILIARY'>
        <xs:annotation>
          <xs:documentation>
            When multiple locations on a piece of bar stock are referenced as
            the indication for the endofbar event, the additional location(s)
            must be designated as auxiliary subtype indication(s) for the
            endofbar event. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PRIMARY'>
        <xs:annotation>
          <xs:documentation>
            Specific applications MAY reference one or more locations on a piece
            of bar stock as the indication for the endofbar event. The main or
            most important location must be designated as the primary subtype
            indication for the endofbar event. If no subtype is specified,
            primary subtype must be the default endofbar event indication.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DELAY'>
        <xs:annotation>
          <xs:documentation>
            A piece of equipment waiting for an event or an action to occur.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LOADED'>
        <xs:annotation>
          <xs:documentation>
            Subparts of a piece of equipment are under load.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OPERATING'>
        <xs:annotation>
          <xs:documentation>
            A piece of equipment are powered or performing any activity.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POWERED'>
        <xs:annotation>
          <xs:documentation>
            Primary power is applied to the piece of equipment and, as a
            minimum, the controller or logic portion of the piece of equipment
            is powered and functioning or components that are required to remain
            on are powered.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='BRINELL'>
        <xs:annotation>
          <xs:documentation>
            A scale to measure the resistance to deformation of a surface.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LEEB'>
        <xs:annotation>
          <xs:documentation>
            A scale to measure the elasticity of a surface.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MOHS'>
        <xs:annotation>
          <xs:documentation>
            A scale to measure the resistance to scratching of a surface.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ROCKWELL'>
        <xs:annotation>
          <xs:documentation>
            A scale to measure the resistance to deformation of a surface.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SHORE'>
        <xs:annotation>
          <xs:documentation>
            A scale to measure the resistance to deformation of a surface.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VICKERS'>
        <xs:annotation>
          <xs:documentation>
            A scale to measure the resistance to deformation of a surface.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ABSOLUTE'>
        <xs:annotation>
          <xs:documentation>
            The position of a block of program code relative to the beginning of
            the control program.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INCREMENTAL'>
        <xs:annotation>
          <xs:documentation>
            The position of a block of program code relative to the occurrence
            of the last linelabel event encountered in the control program.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ALL'>
        <xs:annotation>
          <xs:documentation>
            The count of all the parts produced. If the subtype is not given,
            this is the default.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='BAD'>
        <xs:annotation>
          <xs:documentation>
            Indicates the count of incorrect parts produced.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='GOOD'>
        <xs:annotation>
          <xs:documentation>
            Indicates the count of correct parts made.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='REMAINING'>
        <xs:annotation>
          <xs:documentation>
            Remaining measure of an object or an action.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='JOG'>
        <xs:annotation>
          <xs:documentation>
            The feedrate specified by a logic or motion program, by a pre-set
            value, or set by a switch as the feedrate for the axes. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CONTROL'>
        <xs:annotation>
          <xs:documentation>
            The state of the enabling signal or control logic that enables or
            disables the function or operation of the structural element.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LINE'>
        <xs:annotation>
          <xs:documentation>
            The state of the power source for the structural element.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RADIAL'>
        <xs:annotation>
          <xs:documentation>
            A reference to a radial type tool offset variable.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LENGTH'>
        <xs:annotation>
          <xs:documentation>
            A reference to a length type tool offset variable.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MAINTENANCE'>
        <xs:annotation>
          <xs:documentation>
            Action related to maintenance on the piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OPERATOR'>
        <xs:annotation>
          <xs:documentation>
            The identifier of the person currently responsible for operating the
            piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SET_UP'>
        <xs:annotation>
          <xs:documentation>
            The identifier of the person currently responsible for preparing a
            piece of equipment for production or restoring the piece of
            equipment to a neutral state after production.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='COMPLETE'>
        <xs:annotation>
          <xs:documentation>
            Completion of an action.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='REQUEST'>
        <xs:annotation>
          <xs:documentation>
            A subtype of an interface dataitem type to communicate a request. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RESPONSE'>
        <xs:annotation>
          <xs:documentation>
            A subtype of an interface dataitem type to communicate a response.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CONSUMED'>
        <xs:annotation>
          <xs:documentation>
            The amount of bulk material consumed from an object or container
            during a manufacturing process.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='START'>
        <xs:annotation>
          <xs:documentation>
            The time and date associated with the beginning of an activity or
            event.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TARGET_COMPLETION'>
        <xs:annotation>
          <xs:documentation>
            The projected time and date associated with the end or completion of
            an activity or event.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MANUFACTURE'>
        <xs:annotation>
          <xs:documentation>
            The time and date code relating to the production of a material or
            other physical item.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='EXPIRATION'>
        <xs:annotation>
          <xs:documentation>
            The time and date code relating to the expiration or end of useful
            life for a material or other physical item.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FIRST_USE'>
        <xs:annotation>
          <xs:documentation>
            The time and date code relating the first use of a material or other
            physical item.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SCHEDULE'>
        <xs:annotation>
          <xs:documentation>
            The identity of a control program that is used to specify the order
            of execution of other programs.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MAIN'>
        <xs:annotation>
          <xs:documentation>
            The identity of the primary logic or motion program currently being
            executed. It is the starting nest level in a call structure and may
            contain calls to sub programs.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LICENSE'>
        <xs:annotation>
          <xs:documentation>
            The license code to validate or activate the hardware or software.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VERSION'>
        <xs:annotation>
          <xs:documentation>
            The version of the hardware or software.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RELEASE_DATE'>
        <xs:annotation>
          <xs:documentation>
            The date the hardware or software was released for general use.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INSTALL_DATE'>
        <xs:annotation>
          <xs:documentation>
            The date the hardware or software was installed.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MANUFACTURER'>
        <xs:annotation>
          <xs:documentation>
            The corporate identity for the maker of the hardware or software.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='IPV4_ADDRESS'>
        <xs:annotation>
          <xs:documentation>
            The IPV4 network address of the component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='IPV6_ADDRESS'>
        <xs:annotation>
          <xs:documentation>
            The IPV6 network address of the component.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='GATEWAY'>
        <xs:annotation>
          <xs:documentation>
            The Gateway for the component network.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SUBNET_MASK'>
        <xs:annotation>
          <xs:documentation>
            The SubNet mask for the component network.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VLAN_ID'>
        <xs:annotation>
          <xs:documentation>
            The layer2 Virtual Local Network (VLAN) ID for the component
            network.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MAC_ADDRESS'>
        <xs:annotation>
          <xs:documentation>
            Media Access Control Address. The unique physical address of the
            network hardware.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WIRELESS'>
        <xs:annotation>
          <xs:documentation>
            Identifies whether the connection type is wireless. 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemSubEnumType'>
    <xs:annotation>
      <xs:documentation>
        The sub-types for a measurement
      </xs:documentation>
    </xs:annotation>
    <xs:union memberTypes='DataItemSubEnumTypeEnum DataItemExtType'/>
  </xs:simpleType>
  <xs:simpleType name='DataItemStatisticsTypeEnum'>
    <xs:annotation>
      <xs:documentation>
        Statistical operations on data
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='AVERAGE'>
        <xs:annotation>
          <xs:documentation>
            Mathematical Average value calculated for the data item during the
            calculation period.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='KURTOSIS'>
        <xs:annotation>
          <xs:documentation>
            A measure of the &quot;peakedness&quot; of a probability
            distribution; i.e., the shape of the distribution curve.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MAXIMUM'>
        <xs:annotation>
          <xs:documentation>
            Maximum value of a data entity or attribute.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MEDIAN'>
        <xs:annotation>
          <xs:documentation>
            The middle number of a series of numbers.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MINIMUM'>
        <xs:annotation>
          <xs:documentation>
            The minimum value of a data entity or attribute.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MODE'>
        <xs:annotation>
          <xs:documentation>
            The number in a series of numbers that occurs most often.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RANGE'>
        <xs:annotation>
          <xs:documentation>
            Difference between the maximum and minimum value of a data item
            during the calculation period. Also represents Peak-to-Peak
            measurement in a waveform.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ROOT_MEAN_SQUARE'>
        <xs:annotation>
          <xs:documentation>
            Mathematical Root Mean Square (RMS) value calculated for the data
            item during the calculation period.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='STANDARD_DEVIATION'>
        <xs:annotation>
          <xs:documentation>
            Statistical Standard Deviation value calculated for the data item
            during the calculation period.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemStatisticsType'>
    <xs:annotation>
      <xs:documentation>
        Statistical operations on data
      </xs:documentation>
    </xs:annotation>
    <xs:union memberTypes='DataItemStatisticsTypeEnum DataItemStatsExtType'/>
  </xs:simpleType>
  <xs:simpleType name='UnitsExtType'>
    <xs:annotation>
      <xs:documentation>
        An extension point for data item types
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:pattern value='[a-ln-z]:[A-Z_0-9]+'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='UnitsTypeEnum'>
    <xs:annotation>
      <xs:documentation>
        The unit of measurement for the reported value of the data item.
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='PH'>
        <xs:annotation>
          <xs:documentation>
            A measure of the acidity or alkalinity of a solution.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT_AMPERE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the apparent power in an electrical circuit,
            equal to the product of root-mean-square (RMS) voltage and RMS
            current (commonly referred to as VA).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT_AMPERE_REACTIVE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of reactive power in an AC electrical circuit
            (commonly referred to as VAR).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AMPERE'>
        <xs:annotation>
          <xs:documentation>
            Amps
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CELSIUS'>
        <xs:annotation>
          <xs:documentation>
            Degrees Celsius
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='COUNT'>
        <xs:annotation>
          <xs:documentation>
            A count of something.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DECIBEL'>
        <xs:annotation>
          <xs:documentation>
            Sound Level
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE'>
        <xs:annotation>
          <xs:documentation>
            Angle in degrees
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Angular degrees per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Angular acceleration in degrees per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='HERTZ'>
        <xs:annotation>
          <xs:documentation>
            Frequency measured in cycles per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='JOULE'>
        <xs:annotation>
          <xs:documentation>
            A measurement of energy.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='KILOGRAM'>
        <xs:annotation>
          <xs:documentation>
            Kilograms
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LITER/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Liters per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MICRO_RADIAN'>
        <xs:annotation>
          <xs:documentation>
            Measurement of Tilt
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER'>
        <xs:annotation>
          <xs:documentation>
            Millimeters
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Millimeters per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Acceleration in millimeters per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER_3D'>
        <xs:annotation>
          <xs:documentation>
            A point in space identified by X, Y, and Z positions and represented
            by a space-delimited set of numbers each expressed in millimeters.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='NEWTON'>
        <xs:annotation>
          <xs:documentation>
            Force in Newtons
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='NEWTON_METER'>
        <xs:annotation>
          <xs:documentation>
            Torque, a unit for force times distance.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OHM'>
        <xs:annotation>
          <xs:documentation>
            Measure of Electrical Resistance
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PASCAL'>
        <xs:annotation>
          <xs:documentation>
            Pressure in Newtons per square meter
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PASCAL_SECOND'>
        <xs:annotation>
          <xs:documentation>
            Measurement of Viscosity
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PERCENT'>
        <xs:annotation>
          <xs:documentation>
            Percentage
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='REVOLUTION/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Revolutions per minute
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SECOND'>
        <xs:annotation>
          <xs:documentation>
            A measurement of time.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SIEMENS/METER'>
        <xs:annotation>
          <xs:documentation>
            A measurement of Electrical Conductivity
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT'>
        <xs:annotation>
          <xs:documentation>
            Volts
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WATT'>
        <xs:annotation>
          <xs:documentation>
            Watts
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WATT_SECOND'>
        <xs:annotation>
          <xs:documentation>
            Measurement of electrical energy, equal to one Joule
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LITER'>
        <xs:annotation>
          <xs:documentation>
            Measurement of volume of a fluid
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CUBIC_MILLIMETER'>
        <xs:annotation>
          <xs:documentation>
            Geometric volume in millimeters
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CUBIC_MILLIMETER/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Change of geometric volume per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CUBIC_MILLIMETER/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Change in geometric volume per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIGRAM/CUBIC_MILLIMETER'>
        <xs:annotation>
          <xs:documentation>
            Milligram per cubic millimeter 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER/REVOLUTION'>
        <xs:annotation>
          <xs:documentation>
            Millimeters per revolution.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE_3D'>
        <xs:annotation>
          <xs:documentation>
            A space-delimited, floating-point representation of the angular
            rotation in degrees around the X, Y, and Z axes relative to a
            cartesian coordinate system respectively in order as A, B, and C. If
            any of the rotations is not known, it MUST be zero (0).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='GRAM/CUBIC_METER'>
        <xs:annotation>
          <xs:documentation>
            Gram per cubic meter.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='UnitsType'>
    <xs:annotation>
      <xs:documentation>
        The unit of measurement for the reported value of the data item.
      </xs:documentation>
    </xs:annotation>
    <xs:union memberTypes='UnitsTypeEnum UnitsExtType'/>
  </xs:simpleType>
  <xs:simpleType name='NativeUnitsTypeEnum'>
    <xs:annotation>
      <xs:documentation>
        The native units of measurement for the reported value of the data item.
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='PH'>
        <xs:annotation>
          <xs:documentation>
            A measure of the acidity or alkalinity of a solution.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT_AMPERE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of the apparent power in an electrical circuit,
            equal to the product of root-mean-square (RMS) voltage and RMS
            current (commonly referred to as VA).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT_AMPERE_REACTIVE'>
        <xs:annotation>
          <xs:documentation>
            The measurement of reactive power in an AC electrical circuit
            (commonly referred to as VAR).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='AMPERE'>
        <xs:annotation>
          <xs:documentation>
            Amps
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CELSIUS'>
        <xs:annotation>
          <xs:documentation>
            Degrees Celsius
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='COUNT'>
        <xs:annotation>
          <xs:documentation>
            A count of something.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DECIBEL'>
        <xs:annotation>
          <xs:documentation>
            Sound Level
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE'>
        <xs:annotation>
          <xs:documentation>
            Angle in degrees
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Angular degrees per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Angular acceleration in degrees per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='HERTZ'>
        <xs:annotation>
          <xs:documentation>
            Frequency measured in cycles per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='JOULE'>
        <xs:annotation>
          <xs:documentation>
            A measurement of energy.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='KILOGRAM'>
        <xs:annotation>
          <xs:documentation>
            Kilograms
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LITER/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Liters per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MICRO_RADIAN'>
        <xs:annotation>
          <xs:documentation>
            Measurement of Tilt
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER'>
        <xs:annotation>
          <xs:documentation>
            Millimeters
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Millimeters per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Acceleration in millimeters per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER_3D'>
        <xs:annotation>
          <xs:documentation>
            A point in space identified by X, Y, and Z positions and represented
            by a space-delimited set of numbers each expressed in millimeters.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='NEWTON'>
        <xs:annotation>
          <xs:documentation>
            Force in Newtons
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='NEWTON_METER'>
        <xs:annotation>
          <xs:documentation>
            Torque, a unit for force times distance.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OHM'>
        <xs:annotation>
          <xs:documentation>
            Measure of Electrical Resistance
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PASCAL'>
        <xs:annotation>
          <xs:documentation>
            Pressure in Newtons per square meter
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PASCAL_SECOND'>
        <xs:annotation>
          <xs:documentation>
            Measurement of Viscosity
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='PERCENT'>
        <xs:annotation>
          <xs:documentation>
            Percentage
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='REVOLUTION/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Revolutions per minute
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SECOND'>
        <xs:annotation>
          <xs:documentation>
            A measurement of time.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SIEMENS/METER'>
        <xs:annotation>
          <xs:documentation>
            A measurement of Electrical Conductivity
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='VOLT'>
        <xs:annotation>
          <xs:documentation>
            Volts
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WATT'>
        <xs:annotation>
          <xs:documentation>
            Watts
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WATT_SECOND'>
        <xs:annotation>
          <xs:documentation>
            Measurement of electrical energy, equal to one Joule
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LITER'>
        <xs:annotation>
          <xs:documentation>
            Measurement of volume of a fluid
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CUBIC_MILLIMETER'>
        <xs:annotation>
          <xs:documentation>
            Geometric volume in millimeters
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CUBIC_MILLIMETER/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Change of geometric volume per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CUBIC_MILLIMETER/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Change in geometric volume per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIGRAM/CUBIC_MILLIMETER'>
        <xs:annotation>
          <xs:documentation>
            Milligram per cubic millimeter 
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER/REVOLUTION'>
        <xs:annotation>
          <xs:documentation>
            Millimeters per revolution.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE_3D'>
        <xs:annotation>
          <xs:documentation>
            A space-delimited, floating-point representation of the angular
            rotation in degrees around the X, Y, and Z axes relative to a
            cartesian coordinate system respectively in order as A, B, and C. If
            any of the rotations is not known, it MUST be zero (0).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='GRAM/CUBIC_METER'>
        <xs:annotation>
          <xs:documentation>
            Gram per cubic meter.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='CENTIPOISE'>
        <xs:annotation>
          <xs:documentation>
            A measure of Viscosity
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DEGREE/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Rotational velocity in degrees per minute
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FAHRENHEIT'>
        <xs:annotation>
          <xs:documentation>
            Temperature in Fahrenheit
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FOOT'>
        <xs:annotation>
          <xs:documentation>
            Feet
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FOOT/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Feet per minute
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FOOT/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Feet per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FOOT/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Acceleration in feet per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='FOOT_3D'>
        <xs:annotation>
          <xs:documentation>
            A point in space identified by X, Y, and Z positions and represented
            by a space-delimited set of numbers each expressed in feet.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='GALLON/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Gallons per minute.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INCH'>
        <xs:annotation>
          <xs:documentation>
            Inches
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INCH/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Inches per minute
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INCH/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Inches per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INCH/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Acceleration in inches per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INCH_3D'>
        <xs:annotation>
          <xs:documentation>
            A point in space identified by X, Y, and Z positions and represented
            by a space-delimited set of numbers each expressed in inches.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INCH_POUND'>
        <xs:annotation>
          <xs:documentation>
            A measure of torque in inch pounds.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='KELVIN'>
        <xs:annotation>
          <xs:documentation>
            A measurement of temperature
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='KILOWATT'>
        <xs:annotation>
          <xs:documentation>
            A measurement in kilowatt.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='KILOWATT_HOUR'>
        <xs:annotation>
          <xs:documentation>
            Kilowatt hours which is 3.6 mega joules.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LITER'>
        <xs:annotation>
          <xs:documentation>
            Measurement of volume of a fluid
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LITER/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Measurement of rate of flow of a fluid
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MILLIMETER/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Velocity in millimeters per minute
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OTHER'>
        <xs:annotation>
          <xs:documentation>
            Unsupported units
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POUND'>
        <xs:annotation>
          <xs:documentation>
            US pounds
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POUND/INCH^2'>
        <xs:annotation>
          <xs:documentation>
            Pressure in pounds per square inch (PSI).
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RADIAN'>
        <xs:annotation>
          <xs:documentation>
            Angle in radians
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RADIAN/MINUTE'>
        <xs:annotation>
          <xs:documentation>
            Velocity in radians per minute.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RADIAN/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Velocity in radians per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='RADIAN/SECOND^2'>
        <xs:annotation>
          <xs:documentation>
            Rotational acceleration in radian per second squared
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='REVOLUTION/SECOND'>
        <xs:annotation>
          <xs:documentation>
            Rotational velocity in revolution per second
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='NativeUnitsType'>
    <xs:annotation>
      <xs:documentation>
        The native units of measurement for the reported value of the data item.
      </xs:documentation>
    </xs:annotation>
    <xs:union memberTypes='NativeUnitsTypeEnum UnitsExtType'/>
  </xs:simpleType>
  <xs:simpleType name='CoordinateSystemEnumType'>
    <xs:annotation>
      <xs:documentation>
        The coordinate system to be used for the position
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='MACHINE'>
        <xs:annotation>
          <xs:documentation>
            An unchangeable coordinate system that has machine zero as its
            origin.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WORK'>
        <xs:annotation>
          <xs:documentation>
            The coordinate system that represents the working area for a
            particular workpiece whose origin is shifted within the machine
            coordinate system. If the work coordinates are not currently defined
            in the piece of equipment, the machine coordinates will be used.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemResetValueExtType'>
    <xs:annotation>
      <xs:documentation>
        An extension point for reset types
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:pattern value='[a-ln-z]:[A-Z_0-9]+'/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemResetValueTypeEnum'>
    <xs:annotation>
      <xs:documentation>
        The reset intervals
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='MAINTENANCE'>
        <xs:annotation>
          <xs:documentation>
            Action related to maintenance on the piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ACTION_COMPLETE'>
        <xs:annotation>
          <xs:documentation>
            The value of the data entity that is measuring an action or
            operation is to be reset upon completion of that action or
            operation.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ANNUAL'>
        <xs:annotation>
          <xs:documentation>
            The value of the data entity is to be reset at the end of a 12-month
            period.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='DAY'>
        <xs:annotation>
          <xs:documentation>
            The value of the data entity is to be reset at the end of a 24-hour
            period.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='LIFE'>
        <xs:annotation>
          <xs:documentation>
            The value of the data item is not reset and accumulates for the
            entire life of the piece of equipment.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='MONTH'>
        <xs:annotation>
          <xs:documentation>
            The value of the data entity is to be reset at the end of a monthly
            period.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='POWER_ON'>
        <xs:annotation>
          <xs:documentation>
            The value of the data entity is to be reset when power was applied
            to the piece of equipment after a planned or unplanned interruption
            of power has occurred.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='SHIFT'>
        <xs:annotation>
          <xs:documentation>
            The value of the data entity is to be reset at the end of a work
            shift.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='WEEK'>
        <xs:annotation>
          <xs:documentation>
            The value of the data entity is to be reset at the end of a 7-day
            period.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name='DataItemResetValueType'>
    <xs:annotation>
      <xs:documentation>
        The reset intervals
      </xs:documentation>
    </xs:annotation>
    <xs:union memberTypes='DataItemResetValueTypeEnum DataItemResetValueExtType'/>
  </xs:simpleType>
  <xs:complexType name='HeaderType'>
    <xs:annotation>
      <xs:documentation>
        An XML container in an mtconnect response document that provides
        information from an agent defining version information, storage
        capacity, and parameters associated with the data management within the
        agent.
      </xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base='xs:string'>
        <xs:attribute name='version' type='VersionType' use='required'>
          <xs:annotation>
            <xs:documentation>
              The protocol version number.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name='creationTime' type='CreationTimeType' use='required'>
          <xs:annotation>
            <xs:documentation>
              The time the response was created.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name='testIndicator' type='TestIndicatorType' use='optional'>
          <xs:annotation>
            <xs:documentation>
              Optional flag that indicates the system is operating in test mode.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name='instanceId' type='InstanceIdType' use='required'>
          <xs:annotation>
            <xs:documentation>
              A number indicating which invocation of the agent. 
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name='sender' type='SenderType' use='required'>
          <xs:annotation>
            <xs:documentation>
              The agent identification information. 
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name='bufferSize' type='BufferSizeType' use='required'>
          <xs:annotation>
            <xs:documentation>
              A value representing the maximum number of data entity that MAY be
              retained in the agent that published the response document at any
              point in time.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:complexType name='MTConnectErrorType'>
    <xs:annotation>
      <xs:documentation>
        It is the root XML element of an mtconnecterrors response document.
      </xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name='Header' type='HeaderType'>
        <xs:annotation>
          <xs:documentation>
            An XML container in an mtconnect response document that provides
            information from an agent defining version information, storage
            capacity, and parameters associated with the data management within
            the agent.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:choice minOccurs='1'>
        <xs:element name='Error' type='ErrorType'>
          <xs:annotation>
            <xs:documentation>
              An error, XML element, occurs while interpreting a request for
              information from a client software application or when an agent
              experiences an error while publishing the response to a request
              for information.
            </xs:documentation>
          </xs:annotation>
        </xs:element>
        <xs:element name='Errors' type='ErrorsType'>
          <xs:annotation>
            <xs:documentation>
              An XML container element in an mtconnecterrors response document
              provided by an agent when an error is encountered associated with
              a request for information from a client software application.
            </xs:documentation>
          </xs:annotation>
        </xs:element>
      </xs:choice>
    </xs:sequence>
  </xs:complexType>
  <xs:complexType name='ErrorsType'>
    <xs:annotation>
      <xs:documentation>
        An XML container element in an mtconnecterrors response document
        provided by an agent when an error is encountered associated with a
        request for information from a client software application.
      </xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name='Error' type='ErrorType' minOccurs='1' maxOccurs='unbounded'>
        <xs:annotation>
          <xs:documentation>
            An error, XML element, occurs while interpreting a request for
            information from a client software application or when an agent
            experiences an error while publishing the response to a request for
            information.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
  </xs:complexType>
  <xs:simpleType name='ErrorDescriptionType'>
    <xs:annotation>
      <xs:documentation>
        The text description of the error
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'/>
  </xs:simpleType>
  <xs:simpleType name='ErrorCodeType'>
    <xs:annotation>
      <xs:documentation>
        Provides a descriptive code that indicates the type of error that was
        encountered by an agent.
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base='xs:string'>
      <xs:enumeration value='UNAUTHORIZED'>
        <xs:annotation>
          <xs:documentation>
            The request did not have sufficient permissions to perform the
            request.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='NO_DEVICE'>
        <xs:annotation>
          <xs:documentation>
            The device specified in the URI could not be found.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='OUT_OF_RANGE'>
        <xs:annotation>
          <xs:documentation>
            The sequence number was beyond the end of the buffer.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='TOO_MANY'>
        <xs:annotation>
          <xs:documentation>
            The count given is too large.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INVALID_URI'>
        <xs:annotation>
          <xs:documentation>
            The URI provided was incorrect.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INVALID_REQUEST'>
        <xs:annotation>
          <xs:documentation>
            The request was not one of the three specified requests.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INTERNAL_ERROR'>
        <xs:annotation>
          <xs:documentation>
            Contact the software provider, the agent did not behave correctly.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='INVALID_PATH'>
        <xs:annotation>
          <xs:documentation>
            The xpath could not be parsed. Invalid syntax.
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='UNSUPPORTED'>
        <xs:annotation>
          <xs:documentation>
            The request is not supported by this implementation
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
      <xs:enumeration value='ASSET_NOT_FOUND'>
        <xs:annotation>
          <xs:documentation>
            The asset ID cannot be found
          </xs:documentation>
        </xs:annotation>
      </xs:enumeration>
    </xs:restriction>
  </xs:simpleType>
  <xs:complexType name='ErrorType'>
    <xs:annotation>
      <xs:documentation>
        An error, XML element, occurs while interpreting a request for
        information from a client software application or when an agent
        experiences an error while publishing the response to a request for
        information.
      </xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base='ErrorDescriptionType'>
        <xs:attribute name='errorCode' type='ErrorCodeType' use='required'>
          <xs:annotation>
            <xs:documentation>
              Provides a descriptive code that indicates the type of error that
              was encountered by an agent.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
</xs:schema>