These zeros are supplied by {HEAD ~ the MQ register} which is {TAIL ~ part} of the FPP 
These zeros are supplied by { HEAD ~ the MQ register } which is { TAIL ~ part } of the FPP
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH