digraph {
  pad=0.5; bgcolor="lightgrey";
  node [shape="box"; style="filled";  fillcolor="cyan"];
  edge [labelfontsize=10; minlen=2; labeldistance=4 ];
  LED_OFF -> LED_ON [taillabel="EVT_TICK \n&& counter==0";
    tailport=sw; headport=nw];
  LED_ON -> LED_OFF [taillabel="EVT_TICK \n&& counter==0";
    tailport=ne; headport=se];
}

