{HEAD ~ The signals} on the two wires from {TAIL ~ the integrated circuit} are processed by a shift/latch control circuit that is external to the integrated circuit 
{ HEAD ~ The signals } on the two wires from { TAIL ~ the integrated circuit } are processed by a shift / latch control circuit that is external to the integrated circuit
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH