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