clock-state

<xs:attribute name="clock-state" use="optional">
  <!-- Whether the clock is running or stopped. -->
  <xs:simpleType id="clockState">
    <xs:restriction base="xs:string">
      <xs:enumeration id="clockStateStopped" value="stopped"/>
      <xs:enumeration id="clockStateRunning" value="running"/>
    </xs:restriction>
  </xs:simpleType>
</xs:attribute>