Entry defining a single command operation

<xs:element name="command" minOccurs="1" maxOccurs="unbounded">
    <xs:annotation>
        <xs:documentation>Entry defining a single command operation</xs:documentation>
    </xs:annotation>
    <xs:complexType>
        <xs:all>
            <xs:element name="feature" type="xs:string" minOccurs="1" maxOccurs="1">
                <xs:annotation>
                    <xs:documentation>Name or address to be set</xs:documentation>
                </xs:annotation>
            </xs:element>
            <xs:element name="value" type="xs:string" minOccurs="1" maxOccurs="1">
                <xs:annotation>
                    <xs:documentation>Value to set</xs:documentation>
                </xs:annotation>
            </xs:element>
            <xs:element name="comment" type="xs:string" minOccurs="0" maxOccurs="1">
                <xs:annotation>
                    <xs:documentation>An arbitrary description of the command</xs:documentation>
                </xs:annotation>
            </xs:element>
        </xs:all>
        <xs:attribute name="interface">
            <xs:annotation>
                <xs:documentation>The target or device on which the command operates</xs:documentation>
                <xs:appinfo>order:0</xs:appinfo>
            </xs:annotation>
            <xs:simpleType>
                <xs:restriction base="xs:string">
                    <xs:enumeration value="camera_gentl" />
                    <xs:enumeration value="bitflow_reg" />
                    <xs:enumeration value="bitflow_control" />
                </xs:restriction>
            </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="invoke">
            <xs:annotation>
                <xs:documentation>Specifies when the command will be invoked</xs:documentation>
                <xs:appinfo>order:1</xs:appinfo>
            </xs:annotation>
            <xs:simpleType>
                <xs:restriction base="xs:string">
                    <xs:enumeration value="after_setup" />
                    <xs:enumeration value="before_setup" />
                </xs:restriction>
            </xs:simpleType>
        </xs:attribute>
    </xs:complexType>
</xs:element>