OFF_FLAGS
boot0[OFF_FLAGS] &= 0xf0;
boot0[OFF_FLAGS] |= m_arg;
boot0[OFF_FLAGS] &= o_and;
boot0[OFF_FLAGS] |= o_or;
mbr[OFF_FLAGS] & 0xf, cv2(mbr + OFF_TICKS));
if (!(mbr[OFF_FLAGS] & 1 << (7 - i)) ^ opttbl[i].def)