When flag is zero, an u16 state field is cleared using the input bitmask. When flag is non-zero, it's ORRed using the input bitmask instead. If bitmask 0x4 is clear in the input bitmask, this clears that bit in the value before actually writing the value into state. | When flag is zero, an u16 state field is cleared using the input bitmask. When flag is non-zero, it's ORRed using the input bitmask instead. If bitmask 0x4 is clear in the input bitmask, this clears that bit in the value before actually writing the value into state. |