<(Uninformed conjecture:)
<
<Since the 5380 has no built-in DMA controller of its own, that may explai
<things -- a quick-and-dirty external DMA controller could be built for i
<using just counters if the designers totally blew off any kind of arbitra
<logic vs. the other on-board devices, in that case it would be important 

I'd consider that a possible case.

<also explain why they used a private DMA buffer instead of (some portion
<main memory, that avoids arbitration to main memory too.

True, also avoids bus hogging.  It ma also resolve the byte/16bit/32bit 
access problem as both the chips are byte oriented.

These are those annoying details that docs and prints can solve.

Allison