For counting half clock cycles, the interpreter 30 may double the count of the counter 12 and then add or subtract {TAIL ~ one count} based on the values of {HEAD ~ the GH and GL signals} 
For counting half clock cycles , the interpreter 30 may double the count of the counter 12 and then add or subtract { TAIL ~ one count } based on the values of { HEAD ~ the GH and GL signals }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD