0000nnnn10110011
op1 ← SignExtend32(Rn);
IF (AddressUnavailable(op1))
THROW RADDERR, op1;
IF (MMU() AND DataAccessMiss(op1))
THROW RTLBMISS, op1;
IF (MMU() AND (ReadProhibited(op1) AND WriteProhibited(op1)))
THROW READPROT, op1;
OCBWB(op1);