Device 1, wherein the third sub block includes {HEAD ~ a selective passage gate} of which the input is connected to the output of the second sub block and which is controlled by {TAIL ~ the output} of the first sub block 
Device 1 , wherein the third sub block includes { HEAD ~ a selective passage gate } of which the input is connected to the output of the second sub block and which is controlled by { TAIL ~ the output } of the first sub block
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH