Some event initiates the subroutine for loading data into shift register 10, or conversely, for reading data out of {HEAD ~ the shift register}, such as {TAIL ~ an impeding power interruption} as discussed previously 
such as
Some event initiates the subroutine for loading data into shift register 10 , or conversely , for reading data out of { HEAD ~ the shift register } , such as { TAIL ~ an impeding power interruption } as discussed previously
OTH OTH 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 HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH