When WRITE, CHRDY and RA1 all become “H”, an output signal from {TAIL ~ the NAND circuit} becomes “H”, and {HEAD ~ a write current} flows through the write word line 
When WRITE , CHRDY and RA1 all become “ H ” , an output signal from { TAIL ~ the NAND circuit } becomes “ H ” , and { HEAD ~ a write current } flows through the write word line
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH