a first logic unit which logically operates the first data and {HEAD ~ the first transfer control signal}, and outputs {TAIL ~ the result} of the logical operation 
a first logic unit which logically operates the first data and { HEAD ~ the first transfer control signal } , and outputs { TAIL ~ the result } of the logical operation
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH