As long as {HEAD ~ the periodic pulse} is detected by {TAIL ~ the slave processor}, the output of the master processor remains enabled and the output of the slave processor is disabled 
is detected by
As long as { HEAD ~ the periodic pulse } is detected by { TAIL ~ the slave processor } , the output of the master processor remains enabled and the output of the slave processor is disabled
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH