It will be appreciated that the step of resetting {HEAD ~ counter} 40 could also be a step of presetting {TAIL ~ the counter} to a predetermined number, for example in the case of an embodiment that uses a count down counter to reach a predetermined count 
It will be appreciated that the step of resetting { HEAD ~ counter } 40 could also be a step of presetting { TAIL ~ the counter } to a predetermined number , for example in the case of an embodiment that uses a count down counter to reach a predetermined count
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH