uint32_tmask_byte_control:6;/*These bits are mask control bits for comparison of each of the EMACADDR1 bytes. When set high the MAC does not compare the corresponding byte of received DA or SA with the contents of EMACADDR1 registers. Each bit controls the masking of the bytes as follows: Bit[29]: EMACADDR1 High [15:8]. Bit[28]: EMACADDR1 High [7:0]. Bit[27]: EMACADDR1 Low [31:24]. Bit[24]: EMACADDR1 Low [7:0].You can filter a group of addresses (known as group address filtering) by masking one or more bytes of the address.*/