When the pushbutton switch 80 is closed, the controller unit 66 begins {HEAD ~ execution} of {TAIL ~ the program} 200 at time T0 
of
When the pushbutton switch 80 is closed , the controller unit 66 begins { HEAD ~ execution } of { TAIL ~ the program } 200 at time T0
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH