ISOC_HEADER_SY_MASK
return (header & ISOC_HEADER_SY_MASK) >> ISOC_HEADER_SY_SHIFT;
*header &= ~ISOC_HEADER_SY_MASK;
*header |= (((u32)sy) << ISOC_HEADER_SY_SHIFT) & ISOC_HEADER_SY_MASK;