<
xs:restriction
base="
xs:string
">
<xs:enumeration
value="priority request"/>
<xs:enumeration
value="priority request ack"/>
<xs:enumeration
value="priority update"/>
<xs:enumeration
value="priority update ack"/>
<xs:enumeration
value="priority control"/>
<xs:enumeration
value="priority control ack"/>
<xs:enumeration
value="priority buffer"/>
<xs:enumeration
value="priority buffer response"/>
<xs:enumeration
value="priority cancel"/>
<xs:enumeration
value="priority cancel ack"/>
<xs:enumeration
value="priority clear"/>
<xs:enumeration
value="priority clear ack"/>
<xs:enumeration
value="priority request grant"/>
<xs:enumeration
value="priority request deny"/>
<xs:enumeration
value="priority request downgrade"/>
<xs:enumeration
value="priority request preempted"/>
<xs:enumeration
value="priority request cleared"/>
<xs:enumeration
value="green phase begin"/>
<xs:enumeration
value="green phase end"/>
<xs:enumeration
value="vehicle arrival at queue"/>
<xs:enumeration
value="vehicle arrival at stopbar"/>
<xs:enumeration
value="vehicle clear intersection"/>
<xs:enumeration
value="vehicle delay detected"/>
<xs:enumeration
value="vehicle diversion detected"/>
</
xs:restriction>