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