These two signals GH and GL are routed along with Data1 from counter 12 to {HEAD ~ a means}, represented by block 30, for interpreting the signals GH and {TAIL ~ GL} 
These two signals GH and GL are routed along with Data1 from counter 12 to { HEAD ~ a means } , represented by block 30 , for interpreting the signals GH and { TAIL ~ GL }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL