clements@bbn.com (Bob Clements) (02/14/89)
The DS8390 Ethernet chip from National has a 64-bucket hashing algorithm for multicast addresses. After hashing, it checks one of 64 bits to see whether to drop or accept the multicast frame. It's up to the programmer to set up the bit mask for the desired/undesired multicasts. This chip is used on the WD8003E and the 3Com 3C503 cards among others. The 8390 data sheet that I have says glibly "The system designer should use a program to convert a multicast address to the corresponding mask bit..." (paraphrased). Has anyone written that program? If so, would you share it with me to save me some amount of bit-fiddling? Thanks, Bob Clements clements@bbn.com