MASK5            4305 src/dps8/dps8_cpu.c     w1            |= (proccmd & MASK5) << 7;
MASK5             790 src/dps8/dps8_faults.c     cpu.cu.FI_ADDR   = (word5) fault_number & MASK5;
MASK5            2340 src/dps8/dps8_fnp2_iomcmd.c                     word5 line_type = (subch_data >> 4)  & MASK5;