statechart.xml

<?xml version="1.0" encoding="UTF-8"?>
<scxml xmlns="http://www.w3.org/2005/07/scxml" name="device" datamodel="ecmascript" version="1.0">
  <state id="OK">
    <state id="on">
      <transition target="off" event="device.turnOff"/>
    </state>
    <state id="off">
      <transition target="on" event="device.turnOn"/>
    </state>
    <transition target="error" event="device.error"/>
  </state>
  <state id="error">
    <transition target="OK" event="device.reset"/>
  </state>
</scxml>