Originally Posted by hooverphonique
these dma transfers may be of any size the manufacturer of the busboard decides, and has nothing to do with zorro bus width or anything else amiga-related..
True. However, no bus board has any memory, which is why the GFX card's memory serves as a temporary buffer for the networking card. The CPU then needs to poll the data from that memory (or vice versa; CPU places data into GFX memory and tells NIC to DMA things from that mem). That's the detour I wrote about earlier.
That polling may be as fast as the PIO transfer from/to the X-Surf-100, but since you have to wait for the DMA to be completed, you always have some additional time to wait. As a result, I am claiming to have built the fastest networking solution for the Amiga that has ever been made.