As an example, assume you want the IP core to accept packets with a destination address of 01-1C-23-17-4A-CB. The IP core represents these address bits [47:0] in reverse order as shown below.
Address bits 7:0 = 0x01 -> Hash Code bit 0 (XOR MAC address 7:0) = 1
Address bits 15:8 = 0x1C -> Hash Code bit 1 (XOR MAC address 15:8) = 1
Address bits 23:16 = 0x23 -> Hash Code bit 2 (XOR MAC address 23:16) = 1
Address bits 31:24 = 0x17 -> Hash Code bit 3 (XOR MAC address 31:24) = 0
Address bits 39:32 = 0x4A -> Hash Code bit 4 (XOR MAC address 39:32) = 1
Address bits 47:40 = 0xCB -> Hash Code bit 5 (XOR MAC address 47:40) = 1
Therefore the hash code for this example is 0x37. To accept packets with this address, set bit 0 of the MultiCast Hash Table configuration register at "DWord offset" 0x77 (0x40 + 0x37) to the value of 1.